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2003 Fruit and Vegetable Crops Research Report

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VEGETABLES

All America Selections Vegetables for 2002 and 2003

Richard Durham, Department of Horticulture

Introduction

Recent All America Selections (AAS) winners are promoted through a nationwide display garden program. The association of this author with the display garden program was discussed previously (Durham and Dutton, 2001). Display gardens have been grown at both the University of KentuckyLexington-Fayette County Urban Government Arboretum (hereafter, the Arboretum), the Horticultural Research Farm in Lexington, and at either the Robinson Station in Quicksand or the Research and Education Center at Princeton, in the year of these centers' biennial field days. The purpose of this report is to highlight AAS vegetable winners that were not discussed in the previous report. Descriptions of previous AAS vegetable winners, as well as seed source information can be obtained from the AAS Web site at www.all-americaselections.org.

Materials and Methods

Transplant production and garden establishment was essentially as described previously (Durham and Dutton, 2001). However, the Fayette County Master Gardeners assumed responsibility for growing several of the varieties at the arboretum and incorporated these plants into their ongoing vegetable trial garden.

Results and Discussion

2002 Winners

Basil `Magical Michael'

Both an ornamental and edible sweet basil, `Magical Michael' produces compact plants with a mounded habit reaching a height and spread of about 15 in. Size uniformity is one thing that sets this variety apart from other sweet basil plants. Plants flower about 80 to 90 days from seed. The flowers make the plants attractive as an ornamental and may also be used as a garnish or added to salads. No pest issues were noted.

Cucumber `Diva'

This cucumber combines sweet flavor, disease resistance, and high yield. The fruit are sweet and non-bitter when harvested at 4 to 5 in. long. Normally seedless, a few seeds may grow if pollinated by other cucumber plants. `Diva' produces all female flowers and will set fruit parthenocarpically (without need of pollination). High yields and season-long vigor result from this exclusive production of female flowers and lack of seed production.

Pumpkin F1 `Orange Smoothie'

`Orange Smoothie' is a medium-sized pumpkin with fruit weighing around 5 to 8 pounds. It is promoted as an ideal pumpkin for holiday crafts since it has dark orange, smooth skin (ideal for painting), and a strong, long peduncle (handle). `Orange Smoothie' pumpkins mature in about 90 days from sowing seed. The semi-determinate habit makes vine growth more compact, thus requiring less space. The meat is also sweet and can be used for cooking.

Pumpkin F1 `Sorcerer'

`Sorcerer' is a full-sized pumpkin, weighing 15 to 22 lb, produced on a compact vine reaching only 10 ft. The dark orange pumpkins are round, sporting strong, long peduncles (handles). `Sorcerer' pumpkins mature in about 100 days from sowing. The pumpkins can be used for carving and cooking.

Winter Squash `Cornell's Bush Delicata'

This squash produces very high-quality fruit. The orange flesh indicates it is rich in vitamin A. The sweet flesh is fine textured without coarse strings. The squash have a long shelf life, meaning you can store them into the winter months. This squash matures about 100 days from sowing, and plants remain compact with the mature bush sending out 4- to 6-ft. runners later in the season.

2003 Winners

Melon F1 `Angel'

An early Mediterranean-type melon, `Angel' has a mild flavor, and the crisp flesh is very sweet. The 2- to 3-lb melons have a white interior. The lightly netted skin turns creamy yellow when mature, about 60 days from transplanting to the garden. `Angel' vines will spread 6 to 7 ft.

Squash F1 `Papaya Pear'

This is the first summer squash with a shape similar to a papaya fruit. The bright yellow squash looks like a light bulb with the widest section near the blossom end. `Papaya Pear' is a very early variety, so fruit can be harvested in about 40 days from sowing. Yields per plant are not extremely high; however, the semi-bush plant requires less garden space

Acknowledgments

Thanks to Dr. Win Dunwell for transplanting and caring for the vegetable garden at the Research and Education Center at Princeton in 2002, and Dr. Terry Jones who did the same at the Robinson Station for 2003. Thanks also to April Santanek and Darrell Sloan for helping with the garden at the Horticultural Research Farm and to the Fayette County Master Gardeners who helped with the garden at the Arboretum.

References

• All America Selections, 1311 Butterfield Road, Suite 310, Downers Grove, IL 60515. www.all-americaselections.org.
• Durham, R. and S. Dutton. 2001 All America Selections Vegetable Display Gardens. 2002 Fruit and Vegetable Crops Research Report. Department of Horticulture, University of Kentucky Agricultural Experiment Station Publication PR-470.

Observation of Specialty and Colored Potatoes from Early and Late Harvests

April Satanek, Brent Rowell, and Darrell Slone, Department of Horticulture

Introduction

Blue, red, and yellow potatoes have been grown for many years but recently have caught the attention of gourmet chefs and consumers. Very small, or "creamer," specialty potatoes are highly demanded in larger cities but may not be sought in smaller markets. "Baby reds," or small red potatoes, are gaining popularity with restaurants. Plastic clamshell cartons of mixed color and type potatoes are sold in many stores for premium prices. The yellow potato, Yukon Gold, is an example of a specialty potato that has become mainstream and is now grown on a large scale.

This observation trial was conducted to evaluate the quality and yield characteristics of 18 potato varieties, harvested as early and late potatoes. The varieties Kennebec, Dark Red Norland, and Yukon Gold were included as checks.

Materials and Methods

Most seed potatoes were cut on 14 April into small seed pieces containing at least one eye. Small seed potatoes were planted whole. The true seeds of the variety `Catalina' were sown into 72-cell trays in the greenhouse on 3 April and transplanted into the field on 15 May. On 17 April three white, one russet, four yellow, eight red, and two blue skin varieties were planted in double rows 12 ft. long with 42 in. between rows. Each plot of two rows consisted of 16 hills per row, with 9 in. between hills. Four spacer hills consisting of Kennebec or Red Pontiac were planted to mark the end and beginning of each plot. A preplant application of nitrogen as ammonium nitrate was applied at a rate of 123 lb N/A. Admire 2F was applied to the seed potatoes as they were planted. Sprays of Quadris and Bravo were applied alternately between 22 March and 13 June. Two sprays of Pounce were applied for insect control.

One of the two rows of each variety was hand dug on 23 June. The tubers were then washed and sorted, according to diameter, into grade "A" (> 2 1/4 in.), grade "B" (1 3/4 to 2 1/4 in.), grade "C" or creamers (1 to 1 3/4 in.) and culls. "C" grade potatoes are also called "new" potatoes. The two fingerling varieties were sorted into four categories: short (< 2 in.), medium length (2 to 3 1/2 in.), long (> 3 1/2 in.), and cull. These are market grades, distinct from USDA grades. All tubers of every variety were set out on tables; color, shape, and size characteristics were rated.

Before harvesting the late potatoes, the vines, which had been dead for more than a month, were mowed. On 14 October the second of the two rows was dug with a middle buster plow mounted on a tractor. The varieties were then washed and sorted into same categories used for the 23 June harvest. As before, varieties were rated for color, shape, and size.

Visual ratings. Potatoes were rated for uniformity of shape and size using a scale of 1 to 5, with 1 indicating least uniform and 5 indicating completely uniform. Overall appearance was rated on a scale of 1 to 9, with 1 meaning least attractive and 9 meaning most attractive. Interior and exterior colors were noted, and general observations were recorded.

Results and Discussion

Yield data were calculated as lb/A, based on only one 12 ft. row of potatoes; as this trial was not replicated, these yields should only be considered as relative guides not scientific measurements.

Early harvest. Potatoes harvested before maturity are called "new" potatoes. As expected, the early harvest produced small tubers and low yields (Table 1). In this trial the potato vines were not killed before digging the early potatoes. During the harvesting and washing processes, Reddale, Dark Red Norland, and Caribe suffered extensive skin loss, exposing the potato flesh and diminishing the exterior color. All varieties had some skin loss, but loss of skin was less noticeable for the varieties with same flesh and skin color, like All Blue, Cranberry Red, and All Red. Rose Gold, All Red, and Butte scored the best in overall appearance for the early harvest (Table 2). Cultivars like Kennebec, All Red, and Red Cloud had significant growth cracks.

Late harvest. Larger and higher numbers of potatoes were expected from the later harvest and, on the whole, that is what was recorded. Butte and Russian Banana had very small percentages of the larger grades (Table 3).

Probably due to the postponed late harvest, some cultivars lost the intensity of skin color, but Dark Red Norland, Cranberry Red, Red Cloud, and All Red maintained excellent red skin. Red Gold, Rose Gold, and Caribe exhibited skin color fading and had very dark eyes. Because the vines were dead, all the late potatoes withstood the digging and washing process with skins intact. At the late harvest, Russian Banana had a lot of little knobby growths on its tubers, while Swedish Peanut had none. Butte, Dark Red Norland, and All Blue scored the highest overall appearance rating, and All Blue was rated as having a very uniform shape (Table 4).

Of the white flesh, brown skin potatoes, Butte, a russet, was very attractive and uniform in both harvests but was uncharacteristically small in the late harvest. Catalina, the potato grown from true seed, had small tubers and low yields in both harvests (Tables 1 and 3). Pontiac Red and Cranberry Red had deep eyes, which interfere with cleaning and peeling. Of the fingerling varieties, Swedish Peanut was a bit thicker than Russian Banana, which had many peanut-shaped tubers. Swedish Peanut has a much darker yellow flesh than that of Russian Banana.

When growing specialty or colored potatoes, it is prudent to grow small quantities until a profitable market is established. Specialty or niche markets can be easily oversupplied. Most of the potatoes in the trial are suitable for grower trial. For a small, white flesh, russet-like potato, Butte is an excellent variety because of its size and uniformity. Of the two fingerling varieties, Swedish Peanut was more attractive, an important trait when introducing new types of produce to consumers. Cranberry Red, a red skin and red flesh potato, and Reddale, a red skin potato, performed well in yield and appearance. Red Gold and Rose Gold combine red skin with a yellow flesh, an attractive combination. All Blue, Cranberry Red, and All Red, colored fleshed varieties, are all quality potatoes, but their flesh may be quite striking to a consumer who has eaten only white potatoes.

When an early harvest of new potatoes is planned, vines should be killed well before harvest so that processing of the potatoes does not remove the skin. Potatoes dug early will not store well and will bruise easily, and these factors should be a consideration in marketing.

Acknowledgments

The authors would like to thank the following persons for their hard work and assistance in the successful completion of this trial: Dave Lowry, Phillip Bush, Larry Blandford, Derek Law, Audrey Horrall, Barry Duncil, Courtney Bobrowski, Curtis Gregory, Justin Clark, John C. Clark, Dave Spalding, Selvaprasanna Sanjeevijulian, Ashok Swaminathon, Saravanna Kannan, Kalyan Tangirala, Teerasak Tiamdao (Oa), Tanasit Laosomboon (Koh), and Spencer Helsabeck.

Table 1. Early harvest skin color, yield distribution, and estimated yield for colored and fingerling potatoes, Lexington, Kentucky.
Cultivar	Seed Source	Skin Color1	Grade C2 (%)	Grade B3 (%)	Grade A4 (%)	Lb/A (cwt)
Red Gold	JS	red	23	54	23	216.1
Reddale	TS	red	11	43	45	193.9
Cranberry Red	TS	red	18	75	8	181.7
Rose Gold	TS	pink	31	59	11	175.0
Red Pontiac	SO	red	22	49	30	162.2
All Red	JS	dk red	42	56	2	152.9
Red Cloud	TS	red	34	54	12	119.3
Dk. Red Norland	JS	red	37	49	14	68.4
Corola	TS	yellow	54	42	4	150.4
Yukon Gold	JS	yellow	16	46	38	140.8
Superior	JS	white	14	66	21	146.8
Butte	TS	russet	80	20	0	129.6
Kennebec	SO	white	38	58	3	84.2
Catalina	PA	white	92	8	0	34.0
Caribe	TS	dk blue	14	67	19	193.9
All Blue	JS	violet	78	22	0	145.0
Fingerlings			% Short5	% Medium6	% Long7	Lb/A (cwt)
Swedish Peanut	TS	yellow	37	63	0	152.2
Russian Banana	JS	yellow	50	50	0	107.6
1 Exterior color; dk = dark 2 Grade C = potatoes with diameters between 1 in. and 1¾ in., often called “creamers.” 3 Grade B = potatoes with diameters between 1¾ in. and 2¼ in. 4 Grade A = potatoes with diameters larger than 2¼ in. 5 Short = potatoes less than 2 in. long. 6 Medium = potatoes between 2 in. and 3½ in. in length. 7 Long = potatoes longer than 3½ in.

Table 2. Flesh color and appearance ratings of the colored and fingerling potato early harvest, Lexington, Kentucky.
Cultivar	Flesh Color	Shape Uniformity (1-5)1	Size Uniformity (1-5)2	Overall Appearance (1-9)3
Red Gold	lt yellow	4.0	4.0	7.0
Reddale	white	3.0	4.0	6.0
Cranberry Red	pink	4.0	3.0	7.0
Rose Gold	lt yellow	4.0	4.0	8.0
Red Pontiac	white	3.0	3.0	5.0
All Red	pink	4.0	3.0	8.0
Red Cloud	white	2.0	3.0	6.0
Dk. Red Norland	white	4.0	4.0	7.0
Corola	lt yellow	3.0	3.0	6.0
Yukon Gold	lt yellow	3.0	4.0	5.0
Superior	white	4.0	4.0	6.0
Butte	white	4.0	4.0	8.0
Kennebec	white	3.0	3.0	5.0
Catalina	white	3.0	2.5	6.0
Caribe	white	4.0	3.0	6.0
All Blue	violet	4.0	3.0	7.0
Fingerlings
Swedish Peanut	yellow	3.0	4.0	7.0
Russian Banana	yellow	3.0	3.0	6.5
1 Shape uniformity: 1 = least uniform, most variable, 5 = completely uniform. 2 Size uniformity: 1 = least uniform, most variable, 5 = completely uniform. 3 Overall appearance: 1 = worst, 9 = best.

Table 3. Late harvest skin color, yield distribution, and estimated yield for colored and fingerling potatoes, Lexington, Kentucky.
Cultivar	Seed Source	Skin Color1	Grade C2 (%)	Grade B3 (%)	Grade A4 (%)	Lb/A (cwt)
Cranberry Red	TS	dk red	7	28	65	349.8
Reddale	TS	md red	2	11	88	302.4
Red Gold	JS	red	7	38	55	301.0
All Red	JS	lt red	14	58	28	280.6
Rose Gold	TS	lt pink	7	48	45	270.7
Red Pontiac	SO	lt red	5	24	71	268.4
Red Cloud	TS	md red	5	28	67	224.8
Dk. Red Norland	JS	md red	10	35	56	171.3
Corola	TS	yl/brown	15	47	37	337.6
Yukon Gold	JS	yl/brown	5	33	62	201.2
Butte	TS	russet	28	65	6	284.3
Kennebec	SO	wh/brown	8	56	36	209.5
Superior	JS	yl/brown	7	44	50	158.5
Catalina	PA	lt brown	26	48	26	96.2
Caribe	TS	lt violet	4	28	67	316.1
All Blue	JS	dk violet	25	63	12	226.3
Fingerlings			% Short5	% Medium6	% Long7	Lb/A (cwt)
Swedish Peanut	TS	yl/brown	4	84	11	191.6
Russian Banana	JS	lt yellow	11	83	5	196.0
1 Exterior color; dk = dark, lt = light, md = medium, yl = yellow, wh = white. 2 US grade C = potatoes with diameters between 1 in. and 1¾ in. , sometimes called “creamers.” 3 US grade B = potatoes with diameters between 1¾ in. and 2¼ in. 4 US grade A = potatoes with diameters larger than 2¼ in. 5 Short = potatoes less than 2 in. long. 6 Medium = potatoes between 2 in. and 3½ in. in length. 7 Long = potatoes longer than 3½ in.

Table 4. Flesh color and appearance ratings of the colored and fingerling late potato harvest, Lexington, Kentucky.
Cultivar	Flesh Color	Shape Uniformity (1-5)1	Size Uniformity (1-5)2	Overall Appearance (1-9)3
Cranberry Red	pink	3.5	3.0	7.5
Reddale	white	3.0	3.0	7.5
Red Gold	lt yellow	3.0	2.5	6.0
All Red	pink	2.5	3.0	6.0
Rose Gold	yellow	2.0	2.5	7.0
Red Pontiac	white	1.5	3.0	6.5
Red Cloud	white	2.5	2.5	7.0
Dk. Red Norland	white	3.0	2.5	8.0
Corola	lt yellow	2.0	1.5	6.5
Yukon Gold	yellow	1.5	1.5	5.5
Butte	white	4.0	4.5	8.0
Kennebec	white	2.5	2.5	5.0
Superior	white	2.5	2.0	6.0
Catalina	white	2.0	1.5	4.5
Caribe	white	4.0	4.0	7.5
All Blue	violet	4.5	4.0	8.0
Fingerlings
Swedish Peanut	yellow	3.5	3.5	7.0
Russian Banana	lt yellow	2.0	3.0	6.0
1 Shape uniformity: 1 = least uniform, most variable, 5 = completely uniform. 2 Size uniformity: 1 = least uniform, most variable, 5 = completely uniform. 3 Overall appearance: 1 = worst, 9 = best.

Gourmet Potato "RACE" Trial, 2003

R. Terry Jones and Charles T. Back, Department of Horticulture, Robinson Station

Introduction

Farmers' markets and roadside sales are a significant outlet for Kentucky's vegetable production. Consumers look for new or unique potatoes at these markets. Small, mixed color potato packs are now a hot item at some of Kentucky's urban farmers' markets. Growers who can offer new or novelty potatoes are able to increase their overall sales. An observation trial was established to evaluate 18 potato cultivars harvested as early and late potatoes for their potential production in Kentucky. The potato cultivars Kennebec, Dark Red Norland, and Yukon Gold were used as checks.

Materials and Methods

Based on the soil test results (Table 1), 50 lb of N and 100 lb K₂O/A were applied preplant. One sidedressing of 50 lb N/A was applied just prior to hilling when the plants were 12 to 14 in. tall.

Eighteen potato cultivars were planted (Table 2). The cultivar Cranberry Red, sometimes called All Red, was purchased from two different seed sources and tested as separate cultivars. The potatoes were planted 24-25 April. Varieties were grouped by type and color. Each plot consisted of two rows per cultivar with 42 in. between rows and 9 in. between hills. Plots and rows were 12 ft. long, with 20 hills per row (40 hills per plot). Guard rows were single rows. To separate cultivars, we used "spacer" hills (3 ft. long) between cultivars. We used Red Pontiac between plots planted with white or light skin cultivars and Kennebec between plots planted with red skin cultivars. Catalina, grown from true seed, was transplanted 10 May. Admire 2E was applied on 25 April for early season Colorado potato beetle control. Dual Magnum II at a rate of 2 pt/A was also applied for weed control at that time. Two insecticide sprays (Pounce 3.2EC) were made for Colorado potato beetle control. The potatoes were cultivated twice for weed control in May and hilled once in early June. One row in each plot was harvested early for "new" potatoes, while the other row was left for harvest at maturity. One row of each cultivar was harvested on 16 July. The tubers were then graded and sorted according to size and U.S. No. 1 standards. The late harvest was 13 September, and tubers were sorted and graded. Wet weather delayed this harvest.

Results

Each potato cultivar varies in the number of eyes produced on its tubers. Small tubers of a particular cultivar have the same number of eyes as large tubers. The number of eyes on a seed piece determines the number of stems/hill. Stem number determines the number of potatoes produced/hill. Thus, yield and tuber size in a hill are related to the eye number on the potato seed piece used to plant that hill. The ideal size of a potato seed piece is 1½ to 2½ oz. Results show that most of the 17 potato cultivars had a high percentage of B, or split seed pieces (Table 3). Red Pontiac seed was very large, with 52% of the seed requiring a 4-cut to produce 2-oz seed pieces.

For the early harvest, the highest yielding cultivars were Dark Red Norland, All Red, Red Dale, Caribe, Butte, Red Gold, and Superior (Table 4). Five of these cultivars have red skin. The seven cultivars with the highest overall appearance were Butte, Superior, Yukon Gold, Dark Red Norland, Caribe, Red Gold, and Rose Gold. Five of the cultivars tested were in both groups: Dark Red Norland, Caribe, Butte, Red Gold, and Superior.

For the late harvest, the seven highest yielding cultivars were Red Cloud, Red Pontiac, Rose Gold, Red Dale, Dark Red Norland, Red Gold, and Butte (Table 5). Those cultivars with the best overall appearance were Butte, Red Dale, Red Cloud, Rose Gold, Red Gold, Caribe, and Dark Red Norland. Cultivars that were in both the high yield and best appearance groups included Red Cloud, Rose Gold, Red Dale, Dark Red Norland, Red Gold, and Butte.

The yields of the late harvested potatoes were lower than those of the early harvest because some of the tubers decayed when left in the ground for several months after reaching maturity. The early harvest on 16 July was actually near the time of maturity. Ideally the early harvest should have been the last week of June to the first of July, but rainy weather delayed the harvest.

Yields of two fingerling potatoes were low (Table 6). They did not store well in the ground after maturity, as can be seen by the lower yields at the time of the late harvest. When harvested at maturity, Russian Banana was the better looking potato, but at the late harvest date Swedish Peanut looked nicer.

Six of the potato cultivars were evaluated for culinary characteristics by the Family and Consumer Sciences agents in the Quicksand Area (Table 7). The two highest rated baking potatoes were Russian Banana and Superior, and the best-rated boiled potatoes were Kennebec and Superior.

Potato cultivars that had good yields and appearance, regardless of harvest date, include Dark Red Norland, Butte, and Red Gold. Production of crops for specialty markets is a high risk-reward business. With any unusual or novelty item, growers should limit their production until they are sure that they have an established market.

Table 1. Results for soil tests, gourmet potato RACE trial, for Eastern and Central Kentucky, 2003.
PH	Buffer pH	P	K	Ca	Mg	Zn
5.26	6.5	98	302	2113	179	9.5

Table 2. Potato varieties evaluated in the 2003 "Gourmet" and new potato Race trial for Eastern and Central Kentucky and their skin and flesh colors, reported maturities and disease resistances, sources, tuber characteristics, and storability.
Cultivar	Skin Color	Flesh Color	Maturity (days)	Maturity Class	Disease Resistance1	Source2	Tuber Size or Type	Storability
Superior	White	White	NA3	NA3	NA3	WCF	NA3	NA3
Kennebec	White	White	NA	NA	NA	WCF	NA	NA
Butte	Russet	White	110-135	Late	none listed	TR	NA	NA
XP707 Corola	Gold	Gold	90-110	Mid	none listed	TR		Good
Yukon Gold	Yellowish	Lt. Yellow	70-90	Early	R-leaf roll, potato virus	JS	Med-Lg	Excellent
Swedish Peanut	Gold/Brown	Gold	105-135	Late	none listed	TR	Fingerling	Excellent
Russian Banana	Yellow	Lt. Yellow	NA	Late	R-scab, T-late blight	JS	Fingerling	Good
Dark Red Norland	Red	White	NA	Early	R-scab, PVA, PVY, PLRV	JS	NA	Good
Red Dale	Red	White	70-90	Early	R-verticillium wilt	TR	Large	Good
Red Cloud	Red	White	90-110	Mid	none listed	TR	NA	Excellent
Red Pontiac	Red	White	NA		NA	WCF	NA	NA
Red Gold	Red	Yellow	NA	Early	R- scab, virus	JS	Medium	Fair-poor
Rose Gold	Red	Yellow	90-110	Mid	none listed	TR	NA	Fair
All Red (Cranberry Rd)	Red	Pink	NA	Mid	none listed	JS	NA	NA
Cranberry Red (All Red)	Red	Red	70-90	Early	none listed	TR	NA	Good
All Blue	Blue	Blue	NA	Mid-Late	none listed	JS	Medium	Good
Caribe	Blue	White	70-90	V.Early	none listed	TR		Good
Catalina	Brown	white	70-90	Early	NA	Bejo	Flat	NA
1 R = resistant; T = tolerant; PVA = Potato Virus A; PVY = Potato virus Y; PLRV = Potato leaf roll virus. 2 Sources listed at the end of the 2003 Research Report. 3 NA = not available or not reported.

Table 3. Quantity and percentage of seed in each size class for the 2003 "Gourmet" and new potato Race trial for Eastern and Central Kentucky.
Cultivar	Seed Planted (lb)	Percentage of:
		B-size	2-cut	4-cut
Superior	7.3	51	50	0
Kennebec	17.4	32	38	31
Butte	7.0	29	71	0
XP707 Corola	7.1	13	75	11
Yukon Gold	16.0	36	64	0
Swedish Peanut	7.1	100	0	0
Russian Banana	9.9	81	20	0
Dark Red Norland	8.1	42	55	4
Red Dale	7.2	52	49	0
Red Cloud	6.9	35	66	0
Red Pontiac	27.1	16	33	51
Red Gold	7.4	54	46	0
Rose Gold	7.2	52	48	0
All Red (Cranberry Red)	7.1	29	15	52
Cranberry Red (All Red)	7.0	38	62	0
All Blue	7.3	51	45	4
Caribe	7.3	61	40	0

Table 4. Yield of small medium, large, US #1 and cull potatoes, and ratings of tuber appearance for the first new potato harvest (16 July), 2003 "Gourmet," and new potato race trial for Eastern and Central Kentucky.
Variety	Small <1 7/8 in.			Medium >1 7/8 in.			Large >2 1/4 in.		US # 11 Potatoes (cwt/A)	Culls (lb)	Tuber Appearance
	(no./A)	(lb/A)		(no./A)	(lb/A)		(no./A)	(lb/A)			Skin Color2	Flesh Color2	Shape3	Size3	Appearance4	Comments/Taste
Superior	8297	415		2489	3008		5704	18357	214	0.4	W	W	4	4	8	nice white potato
Kennebec	33188	830		4667	4356		52894	13275	176	5.4	W	W	2	2	4	very variable in size, poor shape with a lot of knobs
Butte	49783	3008		50820	7156		50820	14624	218	0.0	W/R	W	4	3 ½	8-9	very attractive long white
XP707 Corola	40448	1763		44597	4667		52894	12238	169	0.0	W	Y	4	3	7 ½	fairly attractive, nice looking potato
Yukon Gold	9334	415		21780	2697		36300	1823	145	0.0	W	Y/W	4	4	8	nice looking potato
Dark Red Norland	8297	207		33188	3630		7260	23751	274	0.2	R	W	4	4	8	some growth cracks or splits; deep eyes, nice looking
Red Dale	6223	103		16594	1141		59117	22506	236	0.6	R	W	4	2	7	some huge potatoes, nice looking but size variable
Red Cloud	23854	726		352634	3319		52894	13483	176	0.5	R	W	3	2	6	a lot of growth cracks & knobs, fair
Red Pontiac	4667	1763		46671	7053		36300	13068	201	0.0	R	W	4	3	7	fairly nice
Red Gold	4149	104		38374	2178		81934	19290	215	0.0	R	Y/W	4	3	8	attractive, could be redder
Rose Gold	29034	1348		45634	5912		44597	14001	199	0.7	R/W	Y	4	4	8	white skin with pink especially near eyes, nice
All Red (Cranberry Red)	62228	2593		52894	5393		84008	21987	274	1.1	R	W/R	2	2	5	fair shape and size quite variable
Cranberry Red (All Red)	41486	933		30077	2074		41486	7675	97	0.0	R	W	4	2 ½	8	dark red attractive potato
All Blue	4149	103		84008	7364		45634	8297	157	0.3	P	P/W	4	3	6	rough skin, Rhizoctonia infection(?), alligator skin, poor
Caribe	17631	830		33188	4045		64303	18150	222	0.1	P/R	W	4	3	8	purplish red skin color, fairly attractive potato, nice
Catalina	21780	519		18669	1141		12446	1763	29	0.0	W	W	2	2	2	poor yield, very uneven size distribution, no good
1 Marketable yield is all medium and large tubers free from defects. 2 W = White; R = Red; P = Pink; Y = Yellow. 3 Scale of 1 to 5: 1 = least uniform, most variable; 5 = completely uniform. 4 Scale of 1 to 9: 1 = worst, 9 = best.

Table 5. Yield of small medium, large, US #1, and cull potatoes and ratings of tuber appearance for the second new potato harvest (13 September), 2003 "Gourmet," and new potato race trial for Eastern and Central Kentucky.
Variety	Small <1 7/8 in.			Medium >1 7/8 in.			Large >2 1/4 in.		US # 11 Potatoes (cwt/A)	Culls (lb)	Tuber Appearance					Comments/Taste
	(no./A)	(lb/A)		(no./A)	(lb/A)		(no./A)	(lb/A)			Skin Color2	Flesh Color2	Shape3	Size3	Appearance4
Superior	22817	1867		16594	2800		28003	9438	122	0.1	W	W	3	2	6.5
Kennebec	23854	2282		33188	7364		9334	3526	109	2.3	W	W	3	4	6-7	some growth cracks
Butte	56006	6741		44597	10371		10371	4875	152	0.4	W	W	5	4	9	attractive potato
XP707 Corola	65340	7364		20743	6119		10371	4563	107	0.4	W	Y/W	2	2.5	7
Yukon Gold	12446	933		22817	4252		26966	8919	132	0.3	W	W	4	3	7.5	nice potato
Dark Red Norland	18669	1867		15557	2904		32151	12653	156]	0.3	R	W/Y	4	3	8	nice potato
Red Dale	9334	622		20743	3734		30077	15246	190	0.2	R	W	5	4	9
Red Cloud	23854	3008		35263	8919		23854	11409	203	2.5	R	W	4	3.5	8.5	nice looking smooth skin
Red Pontiac	22817	3423		17631	6119		21780	13379	195	0.9	R	W	3	3	7.5	secondary growth knob on some tubers
Red Gold	28003	1452		32151	4149		37337	11409	156	0	R	W	4	3	8
Rose Gold	21780	1348		35263	6534		32151	12861	194	2.7	R	Y/W	3.5	3.5	8.5	not a bad potato
All Red (Cranberry Red)	53931	5912		43560	9645		4149	1452	111	0.8	Purple	W/P	3	3	6.5	small size, elongated flesh w/purple tint
Cranberry Red (All Red)	22817	1556		13483	1659		13483	3008	47	2.1	R	W/R	2.5	2.5	4	poor yield, lots of growth cracks
All Blue	40448	3734		39411	6534		22817	7156	137	2.1	R	W/R	4	4	7.5	nice white with red tint
Caribe	17631	1556		32151	5289		21780	7571	129	0.7	R/P	W	4	4	8	nice
Catalina	7260	207		20743	1763		0	0	18	0	W	W	3	3	5	poor yield and size
1 Marketable yield is all medium and large tubers free from defects. 2 W = White; R = Red; P = Pink; Y = Yellow. 3 Scale of 1 to 5: 1 = least uniform, most variable; 5 = completely uniform. 4 Scale of 1 to 9: 1 = worst, 9 = best.

Table 6. Yield by length size classes, total yield, and cull weight and ratings of tuber appearance for the first (16 July) and second harvest of fingerling potatoes, 2003 "Gourmet," and new potato Race trial for Eastern and Central Kentucky.
Cultivar	Tuber Size Class								Total Yield1 (cwt/A)	Culls (lb)	Tuber Appearance					Comments/taste
	< 2 in. long			2 - 3½ in. long			>3½ in. long
	(no./A)	(lb/A)		(no./A)	(lb/A)		(no./A)	(lb/A)			Skin Color2	Flesh Color2	Shape3	Size3	Appearance4
Harvested 16 July 2003
Swedish Peanut	80897	1452		100603	6430		4149	830	87	0	W	Y	2	2	5	variable, curved shape
Russian Banana	91268	1867		71563	4252		53931	6845	130	0	W	W	3	2	7 or 6.5
Harvested 13 September 2003
Swedish Peanut	68451	3111		52894	4460		35263	4771	123	622	W	Y/W	2	2	7
Russian Banana	32151	1245		39411	2385		30077	3630	73	104	W	Y/W	1	1	5.5
1 Marketable yield is all tubers free from defects. 2 W = White; Y = Yellow. 3 Scale of 1 to 5: 1 = least uniform, most variable; 5 = completely uniform. 4 Scale of 1 to 9: 1 = worst, 9 = best.

Table 7. Culinary evaluation of six selected cultivars grown in the 2003 "Gourmet" and new potato Race trial for Eastern and Central Kentucky.
Cultivar	Method of Preparation
	Baked			Boiled
	Rating	Comments		Rating	Comments
Russian Banana	4	Yellow flesh, good flavor when baked, a little mealy		3	Skin is bitter, flesh is OK, good texture, better baked
Dark Red Norland	2	Good potato flavor, poor texture (too firm)		3.5	Good texture boiled, firm bite, bitter skin
Superior	4.5	Buttery yellow flesh, good baked potato		4	Good flavor, good texture
Yukon Gold	3.5	Yellow flesh, great visual color		3	Buttery yellow flesh, good flavor
Red Dale	1.5	Mushy texture, watery flavor		2.5	Watery flavor, sticky
Kennebec	3	Firm texture		4.5	Very good boiled, good potato flavor
Potatoes tested 4 August 2003. Evaluations were conducted by Martha Yount and Sarah Brandl, Family and Consumer Sciences Agents. Evaluation panel was composed of Family and Consumer Sciences Agents from the Quicksand Area.

Yields and Gross Returns from New Slicing Cucumber Varieties

April Satanek, Brent Rowell, Darrell Slone, and John C. Snyder, Department of Horticulture

Introduction

Early cucumbers bring the best prices, and every grower plans for the best returns, but weather usually dictates field activities. The 2003 growing season clearly demonstrated the importance of timing in planting spring slicing cucumber crops. Early slicing cucumbers continue to be profitable for growers in Central and Western Kentucky especially early in the season, when the market price is high. This is the second year of a fresh market slicing cucumber trial that compares new slicing cucumber varieties' yields and visual characteristics.

Methods and Materials

Fifteen slicing cucumber varieties were compared for yield, potential returns, and overall appearance in the spring of 2003 at the Horticultural Research Farm in Lexington. Dasher II was included as a standard (check) variety, as it is one of the most popular hybrids in the region. All the varieties were gynoecious F1 hybrids with approximately 12% pollinators. All varieties are reported to have disease resistance, although our trial did not evaluate disease.

Cucumbers were seeded in 72-cell flats in the greenhouse on 7 May 2003 and transplanted to the field on 10 June. Most cultural practices followed current commercial recommendations for Kentucky. A total of 60 lb N/A was applied prior to transplanting; an additional 10 lb N/A from ammonium nitrate was fertigated in four weekly doses. All P and K was applied preplant according to recommendations based on soil tests. The insecticide Capture 2 EC was used for cucumber beetles on the seedlings while they were hardening off. For insect control, Platinum was applied as a post-transplant drench one day after transplanting. Two applications of Pounce were applied after 24 June for cucumber beetle control. A fungicide regiment of Bravo, Quadris, and Nu Cop was applied throughout harvest.

Plots consisted of 8 ft. long beds with black plastic and drip irrigation. Bed centers were 8 ft. apart. Single plants were spaced 12 in. apart within double rows (two rows/bed) with approximately 15 in. between double rows (16 plants/plot). Plots were replicated four times in a randomized complete block design. Cucumbers were harvested three times a week between 11 July and 1 August for a total of 10 harvests. After grading into either marketable fruit or culls, fruits were counted and weighed. Marketable fruits were sorted according to USDA grades U.S. Fancy, U.S. No. 1, U.S. No. 1 Large, U.S. No. 1 Small, and U.S. No. 2.

Yields and gross returns. Average yields of each USDA grade were compared using Waller-Duncan's LSD (k-ratio t-tests, P = 0.05) following an analysis of variance. Although yields for these grades are important, we have presented the data in a way that we think is practical for the grower. Making planting decisions based on total yield data alone is not recommended and could lead to disastrous results. Raw data were converted by multiplying the yield of each grade by that grade's actual price for that harvest date. Yields in lb/acre were first converted to boxes/acre by dividing yield by the average weight of one 1 1/9 bushel box of slicing cucumbers (55 lb). Box yields were multiplied by actual average weekly wholesale prices received by a Kentucky cooperative, less box costs, packing charges, and commissions. The resulting single variable "gross return" provides a better indicator of a variety's overall performance, taking into account yields of the different grades and their price differentials

Trellising. All plots were trained on a simple trellis consisting of tomato stakes placed every 4 ft. of row, and tomato twine was wrapped around each stake to create a "fence" on both sides of the bed. Plants were then hung over the strings. The trellis consisted of four or five strings placed about 6 to 8 in. apart.

Fruit appearance ratings. All fruits of each variety harvested from all four replications were graded and laid out on tables for careful examination and appearance ratings on 28 July. Fruits were visually assessed for shape, extent of yellow color, and overall appearance. Appearance ratings took into account, in order of importance, overall attractiveness, shape, shape uniformity, and color.

Results and Discussion

Yields and returns. Varieties are ranked from highest to lowest yield of a combination grade of U.S. Fancy plus U.S. No. 1 fruits in Table 1. This combination corresponds to the trade designation `Superselect'. The U.S. No. 2 grade corresponds to the `Select' category, while fruits of the U.S. No. 1 large grade are usually packed as "24 count" (24 fruits/box). Like last year's study, Daytona, Dasher II, SRQ 2983, and Indy were in the seven highest cultivars in this trial, along with General Lee, Greensleeves, and Turbo (Table 1). None of the yields were significantly different from the others. Daytona, Greensleeves, General Lee, Turbo, Indy, and Stonewall all had average percentages of Superselect (Fancy and No. 1) equal to or higher than 80, although all the varieties had average percentages above 70 (Table 1). Incomes for all varieties were not significantly different except that Daytona earned significantly more than Stonewall, the lowest earning variety.

Dasher II, General Lee, SRQ 2983, SXQ 2387, Speedway, and Slice More received the best ratings for uniformity of shape. Daytona, Dasher II, General Lee Thunder, and Panther received the best ratings for degree of yellowing on fruit. The best overall appearance ratings were given to Dasher II, General Lee, Turbo, Indy, and Thunder. Dasher II and General Lee were attractive fruit, receiving some of the best scores in all three appearance rating categories (Table 2).

Although no one variety significantly outperformed the others, this trial illustrates the importance of planning a crop for optimal return. In this case, rain delayed the planting, thus delaying the first harvest until July 11, after the prices started to decrease (Table 3). Daytona, Dasher II, General Lee, Turbo, Indy, Speedway, and Panther remain on the list of suggested slicing cucumber varieties for Kentucky growers. SRQ 2983, Greensleeves, Cobra, and SXQ 2387 are good for grower trial.

Acknowledgments

The authors would like to thank the following persons for their hard work and assistance in the successful completion of this trial: Dave Lowry, Phillip Bush, Larry Blandford, Derek Law, Audrey Horrall, Barry Duncil, Courtney Bobrowski, Curtis Gregory, Justin Clark, John C. Clark, Dave Spalding, Selvaprasanna Sanjeevijulian, Ashok Swaminathon, Saravanna Kannan, Kalyan Tangirala, Teerasak Tiamdao (Oa), Tanasit Laosomboon (Koh), and Spencer Helsabeck.

Table 1. Marketable yields and gross returns of slicing cucumber varieties and advanced breeding lines; data are averages from four replications at Lexington, Kentucky, 2003. Entries ranked from highest to lowest yield of US Fancy plus US No. 1 grade fruits.
Entry	Seed Source	US Fancy+ US No. 1 (tons/acre)	Marketable Yields1			Gross Returns2 ($/acre)	Overall Appear.
			% Fancy+ No. 1 (%)	US No. 2	US No. 1 large
				tons/acre
Daytona	SW	20.7	83	2.4	1.8	8864	5.0
Dasher II	SW	20.4	79	4.0	1.5	7619	7.5
General Lee	SW	20.1	80	3.3	1.6	7463	7.5
SRQ 2983	SS	19.4	79	3.7	1.4	7166	4.5
Greensleeves	HM	19.1	81	3.1	1.4	6877	6.0
Turbo	RU	18.8	82	3.1	1.0	6663	7.5
Indy	SW	18.8	82	2.8	1.3	6700	7.5
Cobra	UA	18.5	78	3.4	1.7	6959	5.5
SXQ 2387	SS	18.5	73	3.8	3.1	7639	7.0
Speedway	RU	18.4	79	3.3	1.7	6907	5.0
Stonewall	SW	18.0	82	2.6	1.3	6353	7.0
Thunder	SW	17.9	75	3.9	2.2	6999	8.0
Panther	SW	17.8	76	2.7	2.9	7097	5.5
Slice More	SW	17.4	75	3.9	2.0	6852	5.5
SXQ 2389	SS	16.3	71	4.5	2.1	6852	4.5
Waller-Duncan LSD (P = 0.05)		5.9	7.9	1.7	1.2	2327	---
1 The combined yields of USDA grades Fancy and US No. 1 are equivalent to the Superselect marketing category, while US No. 2 grade is equivalent to Select; yields of US No. 1 Large are equivalent to yields of cucumbers used in 24-count packs. 2 Gross returns are calculated for each entry by multiplying yields of each marketing category (Superselect, Select, and 24-count) by its appropriate price for a given harvest date (nine harvests). Prices used were actual average weekly prices received by a Kentucky cooperative from June 22–August 10, 2003. Higher returns may reflect earlier yields and/or higher yields of Superselect cucumbers. Prices are shown in Table 3.

Table 2. Fruit shape, color, and overall appearance assessments for slicing cucumber varieties; scores are averages for all fruits of each variety from four replications harvested on 28 July 2003; varieties are listed from highest to lowest US Fancy + US No. 1 yields.
Entry	Shape1	Fruit Yellowing2	Appear. Rating3
Daytona	2.0	3.5	5.0
Dasher II	4.5	3.5	7.5
General Lee	4.0	3.5	7.5
SRQ 2983	4.0	2.0	4.5
Greensleeves	3.5	2.0	6.0
Turbo	3.5	3.0	7.5
Indy	3.5	3.0	7.5
Cobra	3.0	2.5	5.5
SXQ 2387	4.5	2.5	7.0
Speedway	4.0	2.0	5.0
Stonewall	3.0	2.0	7.0
Thunder	2.5	4.0	8.0
Panther	2.5	4.0	5.5
Slice More	4.5	2.5	5.5
SXQ 2389	3.0	3.0	4.5
1 Shape ratings: 1 = worst (large percentage of misshapen fruits) to 5 = best (most fruits uniform, long, straight, cylindrical). 2 Extent of yellowing: 1 = worst (large percentage of fruit surface yellow on most fruits), 5 = best (no yellow color on most fruits). 3 Appearance ratings: 1 = worst; 9 = best, taking into account, in order of importance, shape, shape uniformity, and color.

Table 3. Average weekly wholesale prices received for slicing cucumbers during the period from 29 June-27 July 2003. The first trial harvest was July 11. Prices are before packing charge and marketing commissions are subtracted. Prices are dollars per standard 1 1/9 bu (55 lb) carton.
Week Ending	Market Grade1
	Superselect+ Select	Small
June 29	14.65	11.25
July 6	10.25	8.60
July 13	7.30	5.25
July 20	7.20	5.25
July 27	7.05	5.00
1 Market grades correspond to the following USDA grades: Superselect = US Fancy + US No. 1; Select = US No. 2; Small = US No. 1 Small.

Trellised Slicing Cucumbers in Western Kentucky

Nathan Howard, Department of Horticulture

Introduction

Fresh market slicing cucumbers have been grown in Western Kentucky for the West Kentucky Growers Cooperative for the last four years. Growers want varieties that produce many long, straight, dark green cucumbers with very little yellowing because they are most profitable. This trial repeats the 2002 study. The objective of the two-year study was to determine if trellising would produce better quality, higher yielding fruit that would pay for the cost of trellising.

Materials and Methods

The cucumber variety chosen for this trial was Speedway, a reliable variety for the cooperative. The trial plots were set up in the field of one of the cooperators/growers in McLean County. The grower assisted with this trial by irrigating the plot and controlling pests and diseases. Plants were started in 242-cell trays and transplanted to the field on 5 May into raised beds set up with black plastic mulch and drip irrigation. The trial was arranged as a randomized complete block design with four replications. Each plot had 50 plants in 18-in. wide double rows with 15 in. between plants within the rows. A pre-plant phosphorus and potassium fertilizer was added according to soil test results. One-half of the 100 lb N/A was applied prior to planting with the remainder applied weekly through drip irrigation at 15 lb N/A per application.

The herbicide Devrinol was used for preemergence weed control. Plots were scouted twice weekly to monitor pests and diseases. The insecticide Pounce was used as needed. Bravo, Kocide, and Maneb fungicides were used alternately throughout the season. An outbreak of anthracnose occurred the last week of June, but the disease was controlled with Quadris, which allowed continued cucumber harvesting.

The treatments used in this trial were 1) no trellis, 2) single-stranded trellis, and 3) double-stranded trellis. The trellis treatments were wrapped in five stringings. Plots were harvested 10 times between 20 June and 22 July.

Single- and double-stranded trellises. In either trellis system, tobacco sticks (52 in.) were driven 9 in. into the raised beds directly in the plant row. One stake was placed every five plants (about 6 ft. apart). Since there were two rows of cucumbers per bed, there were also two rows of stakes on each bed. Two stakes were also set every 25 plants on each row to serve as support for the trellis structure and to allow for a gap to pass harvest buckets across rows. Staked tomato twine was used in stringing. The twine was wrapped around a stake once and then moved to the next stake. Stringing the twine was repeated five times at different positions, beginning at 6 in. above the plastic and ending at the top of the stick. When finished, the trellis looked similar to a five-strand fence. The double-strand trellis type was set up exactly the same as the single-strand trellis but with two strings. Twice before the first harvest, vines were manually trained onto the twine in order to ensure the trellises were fully supporting them.

New tobacco sticks cost $0.15 each. This cost can be amortized over two years resulting in an annual cost of $0.07/stick. Approximately 2,070 sticks are required per acre, so stake cost was about $145 per acre. The estimated labor cost for trellising and removal at the end of the season was estimated at $400 per acre. Total material and labor costs for trellising cucumbers were about $600/acre. Cucumber sale prices are FOB less $1.40 box/packing charge and less 16% marketing commissions. Prices are dollars per standard 1 1/9 bu (55 lb) carton.

Results and Discussion

The growing season was wet with cool temperatures, which slowed cucumber growth. Yields were somewhat lower than those of 2002, but higher prices generally offset this difference. Table 1 lists the prices per box for super-select, select, and 24-count sizes at various harvest dates.

Several trends are important. Generally, yield differences were minimal among the three treatments in each cucumber grade (Table 2). The trellised treatment seemed to yield a few more super-select boxes per acre than the non-trellised treatment. The double-strand treatment did not support the fruit load any better than the single-strand treatment. In addition, its yield was lower overall than that for the single-strand treatment. Therefore, using a double strand was not justified according to this experiment. Cucumbers from trellised vines were more uniform in color due to their better exposure to sunlight, compared to cucumbers from untrellised vines. The trellised cucumbers could have been picked for one more week, but the yields at that point were low, which would not justify the cost of picking.

Costs and returns. Single-strand trellised cucumbers returned the highest yield per acre. When adjusted to an acre basis, the gross dollar return obtained with this treatment was $11,627/acre. When cost of labor and materials were factored in, net return for the single-strand trellis was $11,025/acre. Yields of the non-trellised plot were lower overall than the trellised treatments. Because there were no trellising costs, net returns were $11,078/acre.

In this experiment the additional cost of trellising cucumbers was justified but not by a lot. The 2002 research showed more of a difference in profit. An important factor to consider when trellising cucumber is spray coverage. Spray coverage is generally better with less dense foliage, and cucumbers raised on the ground had fewer disease symptoms during the period when anthracnose was a problem. This would result in fewer culled fruits and increase the grower's net profit. The grower was very pleased with his trellised cucumbers because of the ease of harvest when compared to non-trellised cucumbers.

In conclusion, considering the overall yield and materials cost, this experiment demonstrated that trellising was slightly more profitable than not trellising. The main advantage of trellising was associated with ease of harvest.

Table 1. Average weekly wholesale prices for slicing cucumbers from 20 June-22 July 2003.
Week Ending on	Price per Box
	Super-select1	Select1	24-Count1
28 Jun	$13.32	$8.01	$4.35
5 Jul	$15.16	$9.27	$5.63
12 Jul	$14.46	$5.44	$5.93
19 Jul	$ 3.30	$5.35	$5.00
26 Jul	$10.19	$1.63	$4.84
1 Market grades correspond to the following USDA grades: Superselect = U.S. Fancy + U.S.No.1; Select = U.S. No.2; Small = U.S. No.1 Small; 24-count = U.S. No. 1 Large.

Table 2. Yields of market grades of Speedway slicing cucumbers from trellised and non-trellised plots in McLean County, Kentucky, 2003.
Market Grade	Number of Boxes
	No Trellis	Single-Strand Trellis	Double-Strand Trellis
Superselect	523	536	550
Select	427	378	371
24-count	375	470	393
Culls	130	113	135
Total boxes	1,455	1,497	1,449
Income/acre1	$11,078	$11,025	$10,387
1 $ Income/acre is minus cost of trellising.

Yield and Powdery Mildew Resistance of Fall-Harvested Summer Squash

April Satanek, Brent Rowell, William Nesmith, Darrell Slone, and John C. Snyder, Departments of Horticulture and Plant Pathology

Introduction

Fungal and virus diseases are primary concerns in successfully producing and marketing a fall summer squash crop in Kentucky. Under certain conditions, virus can render a squash crop unmarketable by discoloring fruit and affecting plant growth. Infections of more than one virus commonly occur in fall-harvested summer squash in Kentucky. Watermelon mosaic virus (WMV, formerly WMV-2), zucchini yellow mosaic virus (ZYMV), squash mosaic virus (SqMV), cucumber mosaic virus (CMV), and papaya ringspot virus (PRSV, formerly WMV-1) have all occurred in Kentucky at one time or another and in most other southeastern states.

Many straight neck yellow squash have the precocious yellow (Py) gene that masks the greening effect in summer squash fruits produced on plants infected by CMV or WMV. Unfortunately, precocious yellow summer squash will show the greening effect when PRSV or ZYMV is present. Transgenic squash resistant to PRSV and ZYMV (TG-3+) are supposed to be resistant to all four viruses.

This trial was planned to evaluate 34 squash cultivars in response to virus pressure in a fall planting. The low occurrence of virus disease in this year's trial allowed only one rating of virus damage. The cultivars were evaluated for powdery mildew (PM) resistance, yield, and appearance.

Materials and Methods

Thirty-four summer squash cultivars or advanced breeding lines (15 zucchini, 11 straight neck summer squash, and eight crook or semi-crook neck) were evaluated at the University of Kentucky Horticultural Research Farm in Lexington in the late summer and fall of 2003. These included some of the best performing cultivars from the 2002 trial. Most cultural practices were according to current commercial recommendations for Kentucky. Seeds were sown in the greenhouse on 16 July in 72-cell plastic trays and transplanted to the field on 11 August. Each plot consisted of eight plants spaced 18 in. apart in a single row on 6-in. high raised beds with black plastic mulch and drip irrigation. Beds were 8 ft. apart from center to center. All 34 entries were planted together in a randomized complete block design with four replications. Cultivars of each type (zucchinis, yellow straightneck, or yellow crookneck) were grouped together within each block. Blocks consisted of two long rows with 17 entries per row. Single rows of the disease-susceptible cultivar Dixie were planted on both sides of each block to enhance natural disease buildup and uniform spread throughout the trial.

One hundred pounds N/A were applied prior to planting while an additional 27 lb N/A were applied in four applications for a total of 128 lb N/A. All P and K were applied preplant according to soil test recommendations. When cucumber beetle populations were high, Pounce was applied, and for disease control, Bravo and Nova were applied. The preemergent herbicide Curbit was applied between rows for weed control.

Plots were harvested three days a week (MWF) from 29 August to 1 October for a total of 13 harvests. A hard frost on 3 October damaged plants, preventing further harvests. After harvesting, fruits were counted and weighed after grading into either marketable fruit or culls. Marketable yield is expressed as the number of half-bushel boxes per acre by dividing the total weight of marketable fruit per acre by 21 lb. Following an analysis of variance, average yields and disease ratings were compared using Waller-Duncan's K-ratio T-test (P = 0.05).

Fruit quality ratings All fruits of each trial entry harvested from all four replications were graded and laid out on tables for careful examination and quality rating on 15 September. Both the yellow squash and the zucchini squash color were evaluated for uniformity with a score of 1 = highly variable to 5 = uniform, and scores were lowered for green tinted fruit. Appearance was rated on a 1 to 9 scale with 1 = worst and 9 = best, taking into account, in order of importance, overall attractiveness, shape, uniformity of shape, and color.

Disease assessments. Because of a lack of virus symptoms and virus transmitting aphids early in the season, a few plants in all four replications were inoculated with leaves containing virus symptoms and aphids on 19 August. These insect and disease-infested leaves were taken from an infected field of cucurbits. Plants were visually assessed for the extent of PM symptoms on 18 September and assessed for virus symptoms on 13 October. In both cases, a subjective rating of 0 to 5 was used, 0 meaning no disease present and 5 indicating the highest level of disease.

Results and Discussion

The beginning of the fall growing season was marked by a low occurrence of virus diseases in the squash plots but with a significant occurrence of powdery mildew. The season was rainy, and an early frost severely injured most plants.

Yellow straightnecks. Of the yellow straightneck varieties, Conqueror III, a transgenic variety, yielded significantly more than the other straightneck varieties and also received a very low virus score (Table 1). In last year's trial, Conqueror III was one of the lowest yielding under very low virus pressure. Precious II, Cougar, Lioness, and Multipick were the next highest yielding varieties, although not significantly lower than Conqueror III. They earned low virus scores. Lioness received the lowest PM rating among straightneck squash, as well as low rating for virus symptoms. Conqueror III and Precious II had low virus scores but had average PM scores. XPT 1832, a transgenic variety with the precocious gene, along with Superpik, were lowest yielding in our trial. Cougar and Superpik had the most PM symptoms, and Seneca Supreme and Daisy had the most virus symptoms. Despite marginal to bad disease ratings, Multipick, Seneca Supreme, and Daisy received the highest appearance ratings, while Precious II received a low appearance rating because of the highly variable fruit color and shape (Table 2).

Yellow crooknecks. Medallion yielded significantly more than other yellow crooknecks, although it received rather high PM and virus ratings (Table 1). The next highest yielding crooknecks, Gentry, Destiny III, Dixie, Prelude II, and Sunglo all rated low for virus symptoms. As in last year's study, Prelude II and Sunglo had lower PM ratings than the other crooknecks. Prelude II, Sunglo, and Supersette rated highest in appearance, with the other cultivars having acceptable appearances (Table 2).

Zucchini. Of the top five yielding varieties, Radiant yielded the highest but not significantly higher than Payroll, Wildcat, Tigress, and Zucchini Elite (Table 1). Of the top yielders, Payroll, Wildcat, and Zucchini Elite exhibited relatively good PM resistance, along with the lower yielding Senator. All the zucchini in the trial had low virus ratings. In last year's trial, Cashflow, Sensor (9523), and ACX 45a were some of the hardest hit by PM, and these, along with Radiant, Spineless Beauty, Independence II, and EXP718, again received high PM scores this year. All the zucchini varieties received acceptable appearance ratings, but Payroll, Wildcat, Tigress, and Robuster received the highest scores (Table 2).

Marketable yields in late plantings can be expected to vary considerably among cultivars from year to year. Differences depend on the resistance package in the cultivar, diseases present in the field, and the growth stage at which the crop becomes infected. Precocious yellow straightneck cultivars still remain an excellent choice for high yields and masking of green fruit symptoms caused by WMV and CMV.

When virus diseases are a serious risk, transgenic virus-resistant cultivars should perform considerably better in most late summer plantings. Conqueror III, Cougar, Lioness, and Sunray are recommended for small-scale trial. Multipik and Fortune will remain on our list of suggested cultivars for Kentucky growers in spite of their susceptibility to PM. Precious II has performed well for the second year in a row, but it is not recommended for trial because of the varied appearance observed in this year's trial.

Of the crookneck varieties, Destiny III and Prelude II are recommended for growers. Although not yielding the highest in this trial, they both did well under low virus pressure. Medallion, Gentry, and Sunglo are recommended for trial. Among zucchini, Tigress, Zucchini Elite, and Spineless Beauty continue to be recommended. Radiant, Payroll, Cashflow, and Senator are recommended for grower trial, as well as Wildcat for its stunning black appearance. Disease resistance in any type of summer squash should be considered when choosing a variety since productivity often relies on the severity of disease occurring in any particular season.

Acknowledgments

The authors would like to thank the following persons for their hard work and assistance in the successful completion of this trial: Dave Lowry, Phillip Bush, Larry Blandford, Kirk Ranta, Derek Law, Audrey Horrall, Barry Duncil, Courtney Bobrowski, Curtis Gregory, Justin Clark, Dave Spalding, Selvaprasanna Sanjeevijulian, Kalyan Tangirala, Teerasak Tiamdao (Oa), Tanasit Laosomboon (Koh), Spencer Helsabeck, and John C. Clark.

Table 1. Yields and powdery mildew assessments for yellow straightneck, crookneck, and zucchini squash cultivars and breeding lines. Data are means of four replications.
Entry	Source	Type1	Mkt. Yield (boxes/acre)2	Disease Rating3		Appear. Rating4
				PM	Virus
I. Yellow straightneck and slight semi-crookneck:				18 Sept	13 Oct
Conqueror III	SW	SN, Tg-3+	1027	2.4	0.3	6.5
Precious II	AC	SN-Py	806	2.6	0.3	4.5
Cougar	SW	SN-Py	732	3.8	1.5	6.5
Lioness	SW	SN	713	1.8	1.0	6.0
Multipik	HM	SN-Py	672	3.3	1.5	8.0
Sunray	SW	SN-Py	643	2.8	2.0	7.0
Fortune	RG	SN-Py	629	3.5	2.3	7.0
Seneca Supreme	SM	SN-Py	626	3.5	2.8	8.0
Daisy	SM	SN-	566	3.1	2.5	7.5
Superpik	HM	SN-Py	544	3.9	2.3	6.5
XPT 1832	SM	SN-Py, Tg-3	384	3.1	1.5	6.0
II. Yellow semi-crookneck or crookneck:
Medallion	AC	SCN	906	3.3	3.5	6.5
Gentry	RG	sCN	704	3.4	1.5	6.5
Destiny III	SW	sCN, Tg-3	668	3.6	0.0	6.0
Dixie	SM	CN	595	3.5	2.0	6.5
Prelude II	SW	CN, Tg-3	567	1.0	0.3	7.0
Sunglo	RG	sCN	505	1.4	0.8	7.0
Supersette	HM	CN-Py	500	2.5	3.0	7.0
Pic-N-Pic	SW	CN	400	3.5	0.3	6.0
Waller-Duncan LSD (all yellow squash, P = 0.05).			150	.77	.89	---
III. Zucchini:
Radiant	SM	Z	1099	3.4	0.3	6.5
Payroll	RG	Z	1080	2.4	0.0	8.0
Wildcat (HMX0710)	SW	Z	1011	1.8	0.0	8.5
Tigress	SW	Z	951	2.9	0.3	7.5
Zucchini Elite	HM	Z	918	2.1	0.5	7.0
Cashflow	RG	Z	899	3.5	0.5	7.0
Spineless Beauty	RG	Z	874	3.4	0.3	6.0
Independence II	SW	Z,Tg-2	849	3.9	0.0	5.5
ACX 45a	AC	Z	822	3.8	0.0	5.5
Senator	SW	Z	763	1.9	1.3	7.0
Sensor (9523)	SS	Z	763	3.6	0.0	5.0
Dividend	RG	Z	758	3.0	0.0	7.0
Robuster	SS	Z	751	3.0	0.8	7.5
EXP 718	SW	Z	708	3.7	0.3	6.5
Revenue	RG	Z	614	3.0	0.0	6.5
Waller-Duncan LSD (zucchinis, P = 0.05)			181	1.1	1.4	--
1 All entries from conventional breeding programs except for: Tg = transgenic for resistance to two (Tg-2) or three (Tg-3) viruses; Tg-3+ = transgenic for three viruses with resistance to the fourth (PRSV) obtained through conventional breeding. Type descriptions based on our observations on 15 Sept.: SN = straightneck, CN = crookneck, sCN = semi-crookneck; some cultivars that we considered semi-crookneck are considered straightneck by the seed company and are included in the straightneck grouping; Py = has precocious yellow gene to mask virus symptoms. 2 Number of half-bushel (21lb = 9.52 kg) boxes per acre. 3 Visual rating scale from 0 = no symptoms to 5 = extensive symptoms on entire plants; ratings took into account the percentage of upper and lower leaf and stem surfaces that were covered by powdery mildew and virus symptoms; assessed by W. Nesmith on 18 Sept and 13 Oct. 4 Appearance ratings: 1 = worst, 9 = best, taking into account, in order of importance, overall attractiveness, shape, and color.

Table 2. Fruit color, appearance, and other observations for yellow straightneck, crookneck, and zucchini squash cultivars and breeding lines. All fruits bulked from four replications of the harvest.
Entry	Type1	Color Uniform2	Appear Rating3	Shape/Comments/Suitability
Conqueror III	SN-Py Tg-3+	2.5	6.5	Light yellow, long fruit with faint longitudinal yellow lines
Medallion	sCN	3.5	6.5	Light yellow, medium sized bulb
Precious II	SN-Py	1.5	4.5	Medium yellow to light green, variable shape and color
Cougar	SN-Py	4.0	6.5	Medium yellow
Lioness	SN	3.0	6.0	Pale yellow, long cylindrical fruit with thick neck
Multipik	SN-Py	5.0	8.0	Medium yellow, thick, short fruit
Sunray	SN-Py	3.5	7.0	Medium yellow
Fortune	SN-Py	4.0	7.0	Medium yellow
Seneca Supreme	SN-Py	4.0	8.0	Medium yellow, thick, short fruit
Daisy	SN	1.5	7.5	Light yellow to slight green
Superpik	SN-Py	4.5	6.5	Medium yellow
XPT 1832	SN-Py, Tg-3	4.0	6.0	Medium yellow
Gentry	sCN	3.0	6.5	Medium yellow, large bulb
Destiny III	sCN, Tg-3	2.0	6.0	Medium yellow, large bulb
Dixie	CN	2.0	6.5	Pale yellow
Prelude II	CN, Tg-3	1.5	7.0	Medium yellow
Sunglo	sCN	3.0	7.0	Light yellow, smooth fruit
Supersette	sCN-Py	5.0	7.0	Medium yellow
Pic-N-Pic	CN	4.0	6.0	Yellow to light green, bulbous blossom end
Radiant	Z	3.5	6.5	Dark green
Payroll	Z	5.0	8.0	Medium green
Wildcat (HMX0710)	Z	5.0	8.5	Very dark green mottled with light. green
Tigress	Z	4.5	7.5	Medium green, nice appearance, uniform size and color
Zucchini Elite	Z	3.5	7.0	Medium green, all a bit curved
Cashflow	Z	3.0	7.0	Dark green, all slightly curved
Spineless Beauty	Z	3.5	6.0	Medium green, stem extends onto the top of the fruit
Independence II	Z, Tg-2	4.5	5.5	Medium green, slightly curved
ACX 45a	Z	4.0	5.5	Black, attractive
Senator	Z	4.5	7.0	Light green
Sensor (9523)	Z	4.5	5.0	Dark green, small at top, larger at blossom end
Dividend	Z	4.0	7.0	Very dark green, slightly curved
Robuster	Z	4.0	7.5	Medium green, attractive
EXP 718	Z	3.0	6.5	Medium green, slightly curved
Revenue	Z	4.0	6.5	Medium green, slightly curved
1 Type descriptions based on our observations on 15 Sept.: SN = straightneck, SN-Py = straightneck with precocious yellow gene, CN = crookneck, sCN = semi-crookneck. Some cultivars that we considered semi-crookneck may be considered straightneck by the seed company. 2 Color ratings for yellow squash: 1 = variable color, light green; 5 = bright golden yellow, uniform color; for zucchini, 1 = variable color; 5 = uniform color. 3 Appearance ratings: 1 = worst; 9 = best, taking into account, in order of importance, overall attractiveness, shape, and color.

Bell Pepper Cultivar Trial, Western Kentucky

Nathan Howard, Department of Horticulture

Introduction

Bell pepper has become a major commercial vegetable crop in Western Kentucky. Demand for pepper has increased in this area due to the strong marketing potential established through the West Kentucky Grower Cooperative, based in Owensboro, Kentucky. In the continuing search for new and improved varieties best suited for our region, we conducted a variety trial to determine if the cultivars currently used are the best fit for our area and to evaluate new cultivars not grown in this area before.

Materials and Methods

The trial was conducted in cooperation with a pepper grower in Daviess County. Seed of 10 bell pepper varieties was obtained from Seedway Company. On 22 May, 10 varieties were transplanted onto raised beds set up with black plastic mulch and drip irrigation. The trial was arranged as a randomized complete block design with four replications. Each plot had 20 plants in 18-in.-wide double rows, with 15 in. between plants within the rows. A pre-plant phosphorus and potassium fertilizer was applied according to soil test results. In addition, a broadcast application of 75 lb N/A was applied pre-plant, with the remaining 235 lb N/A applied at a rate of 15 to 25 lb/week with the last application on 18 August. Disease and insects were controlled by weekly applications of Manex and Copper fungicides, and by Mustang Max insecticide, applied as needed. Income per acre was calculated based on the price and number of boxes of each pepper size. Prices are per standard 1 1/9 bu (55 lb) carton. Prices are FOB less $1.40 per box for packing charge and by 16% for marketing commission.

Results and Discussion

The growing season was very good with abundant rain in spring and summer, and lush growth was noticeable throughout the growing season. The trial plots were harvested six times between 23 July and 5 September. Yields were very good with the top yielder, Olympus, producing 1,600 boxes/A (Table 1). Olympus also yielded the most extra-large peppers and the fewest culls in the trial. Brigadier and Revolution also yielded well, producing more than 1,500 boxes/A. Although Brigadier had a high yield, fruits were not as uniform as for other varieties. In addition, more culls and choppers were graded out of Brigadier than any other variety in the trial. Although Brigadier and Defiance had more total yield than Crusader and Red Knight, the latter outperformed Brigadier and Defiance in their proportion of extra-large fruits. Aristotle X3R produced the most uniform amounts of extra-large, large, and medium fruits. Aristotle X3R was also very profitable, as it was rated the third highest for income/A. Orion was the lowest yielding pepper variety in the trial (~1,000 boxes/A) and had the lowest income. Prices started high in July but fell off later in the month and did not recover. Still, the average price was determined to be profitable (Table 2).

In conclusion, we were able to better determine which varieties performed best for our region. Olympus was rated the best new variety, as it held up well and was found most profitable. Other promising varieties include Brigadier and Aristotle X3R. This trial will be repeated in 2004 to confirm these results and to compare the overall performance of the top varieties.

Table 1. Maturity, yields (boxes/A), and income ($/A) for a bell pepper variety trial conducted at West Kentucky Grower Cooperative in Daviess County, Kentucky, 2003.
Variety1	Maturity (days)	Extra Large	Boxes/A				Total Yield	Income ($/A)
			Large	Medium	Chopper	Culls
Olympus	71	535	618	379	99	2	1633	12,922
Revolution	74	493	562	391	68	15	1529	12,048
Brigadier	71	249	569	422	229	39	1508	10,618
Crusader	74	356	531	415	44	10	1356	10,519
Defiance	72	219	482	421	220	11	1353	9,653
Red Knight	64	319	524	407	90	5	1345	10,253
Heritage	74	251	524	429	106	15	1325	9,808
Aristotle X3R	72	489	478	258	75	2	1302	10,481
X3R Wizard	73	279	514	369	26	15	1203	8,382
Orion	74	293	357	382	27	8	1067	7,473
1 Sorted by total yield.

Table 2. Average wholesale prices for bell peppers in 2003.
Grade	Price
X-Large	$10.02
Large	$7.03
Medium	$7.27
Chopper	$4.61

Sweet Corn Variety Trial, Western Kentucky, 2003

Joseph G. Masabni, Shane Bogle, and Dwight Wolf, UK Research and Education Center, Department of Horticulture

Introduction

New varieties of sweet corn are always being developed. The newest trend in sweet corn is the combination of high sugar content of enhanced sugar varieties and the crunchy kernel of older varieties. The West Kentucky Grower Cooperative, based in Owensboro, Kentucky, seeks new varieties that would appeal to the market or the consumer. These varieties would help the cooperative and its members, the growers, stay in business. Toward that goal, a sweet corn variety trial was conducted in 2003 to evaluate 10 new and improved sh2 varieties.

Materials and Methods

Ten supersweet sweet corn varieties were provided by the West Kentucky Growers Cooperative for evaluation at the University of Kentucky Research and Education Center at Princeton, Kentucky. The trial consisted of four bicolor, three white, and three yellow sweet corn varieties as shown in Table 1.

The experimental design was a randomized complete block design with three replications and 10 treatments, with sweet corn varieties as treatments. Plots were 35 ft. long and 80 in. wide. Each plot was seeded with a plate seeder calibrated to seed two rows of corn 40 in. apart at 9-in. spacing within rows. A 10-ft. alley was left between replications 1 and 2 and between replications 2 and 3, to facilitate spraying, harvesting, and other maintenance. Prior to seeding, fertilizer and lime were amended according to the soil test results. A drip irrigation system was set up with one line of drip tape per variety across the whole plot. Soluble N was added through the drip irrigation every two weeks after germination. The trial was seeded on 22 April.

On 14 May Atrazine (1 qt/A) was broadcast over the whole plot to control emerged and emerging weeds. On 18 June Poast (1 qt/A) and COC 1% (v/v) were sprayed with a backpack sprayer and a 2-nozzle shielded boom, for control of emerged grasses growing between the treatments. No fungicides were applied, and only one application of Sevin was applied at tassel stage for insect control.

Results and Discussion

Table 2 lists the variables measured for each sweet corn variety. 6800 Y and 6802R BC, the first varieties harvested, had the highest number of ears/plant, total number of ears per plot, and the highest germination percentage. Ear weight did not differ significantly among the 10 varieties, even though ear weight ranged from 6.5 to 7.8 oz.

8102R BC had the longest marketable ears, followed closely by Camas BC. In turn, Camas BC, Saturn Y, and 8102R BC had the widest ears.

Table 3 lists the 10 varieties in descending order for each variable. This allows quick comparison of the rankings. Camas BC is in the top third for all variables except plant height. 8102R BC and two varieties of Saturn were also in the top three varieties for ear length, width, and weight. AC945 Y was in the lowest third for all measured varieties except for ear width.

No taste study was conducted on these varieties. However, comments were solicited from those who tasted them. Most liked the bicolor look of the sweet corn but mentioned that they usually buy what is available in the store. If given a choice, they will buy a familiar brand name. The white kernel varieties received the most extreme opinions, either totally loved or hated for their sweetness and crunch and for their pale color.

Acknowledgment

The authors wish to acknowledge the excellent technical support provided by June Johnston and Hilda Rogers.

Table 1. Variety, colors, and sources of supersweet corn, UKREC, Princeton, Kentucky, 2003.
Variety	Color	Source
6802R	Bicolor	AC
8102R	Bicolor	AC
Camas or BSS9686	Bicolor	SW
Saturn	Bicolor	SW
8101R	White	AC
Boreal	White	SW
Saturn	White	SW
AC945	Yellow	AC
6800	Yellow	AC
Saturn	Yellow	SW

Table 2. Germination and plant and ear characteristics of sweet corn in the 2003 variety trial at UKREC, Princeton, Kentucky.
Variety	Germination Percent 28 May	Plant Height (in.)	Ear Length (in.)	Ear Width (in.)	Ear Weight (oz)	Number Ears/ Plant	Total Ear Number	Harvest Date(s) (July)
6802R BC	100	58	7.6	1.7	6.8	1.2	61	9, 14
6800 Y	100	61	7.5	1.7	7.1	1.0	58	9, 14
Camas BC	100	62	7.9	1.8	7.8	1.0	56	21
Saturn Y	89	62	7.4	1.9	7.4	1.1	45	21
Boreal W	68	65	7.4	1.8	7.3	1.3	41	21
8102R BC	79	64	8.3	1.8	7.8	1.1	39	21
Saturn BC	96	64	7.4	1.8	7.5	1.1	51	16, 21
8101 W	72	58	7.7	1.6	6.7	1.4	46	16, 21
Saturn W	85	62	7.4	1.8	6.5	1.3	50	14, 16
AC 945 Y	81	61	7.3	1.8	6.6	1.0	37	14, 16
LSD 5%	20	3	4.4	1.2	NS	0.3	15
CV	14	3	1.3	1.6	13.5	13.6	18

Table 3. Sweet corn varieties listed in descending order for each measured variable.
Germination Percent 28 May	Plant Height (in.)	Ear Length (mm)	Ear Width (mm)	Ear Weight (g)	Number Ear/Plant	Total Ear Number
6800 Y	Boreal W	8102R BC	Saturn Y	8102R BC	6802R BC	8101 W
6802R BC	Saturn BC	Camas BC	8102R BC	Saturn BC	6800 Y	Boreal W
Camas BC	8102R BC	8101 W	Camas BC	Camas BC	Camas BC	Saturn W
Saturn BC	Camas BC	6802R BC	Boreal W	Saturn Y	Saturn BC	6802R BC
Saturn Y	Saturn Y	6800 Y	AC 945 Y	Boreal W	Saturn W	Saturn BC
Saturn W	Saturn W	Boreal W	Saturn BC	6800 Y	8101 W	Saturn Y
AC 945 Y	6800 Y	Saturn BC	Saturn W	6802R BC	Saturn Y	8102R BC
8102R BC	AC 945 Y	Saturn Y	6802R BC	8101 W	Boreal W	6800 Y
8101 W	6802R BC	Saturn W	6800 Y	AC 945 Y	8102R BC	AC 945 Y
Boreal W	8101 W	AC 945 Y	8101 W	Saturn W	AC 945 Y	Camas BC

Supersweet Corn Evaluations in Central Kentucky, 2003

John Strang, April Satanek, Terry Jones, Chris Smigell, Darrell Slone, and John Snyder, Department of Horticulture

Introduction

Locally produced sweet corn is a high demand item at Kentucky retail markets. This trial was designed to evaluate newer supersweet corn varieties under Central Kentucky conditions.

Materials and Methods

Forty-eight supersweet corn varieties were planted by hand on 14 May 2003. Plots consisted of a 20-ft. long row of each cultivar, replicated four times. Rows were spaced 3.5 ft. apart, and 100 seeds were planted in each 20-ft. row. Plants were thinned to a distance of 8 in. apart on June 10.

Prior to planting 100 lb of actual N per acre was applied as ammonium nitrate and tilled in. Plants were sidedressed with 50 lb of actual N per acre as ammonium nitrate.

Bicep at the rate of 1.8 qt per acre was applied on 14 May for weed control. Pounce, Sevin, Asana, and Warrior were used for insect control.

Results and Discussion

Variety evaluation results can be found in Tables 1 through 3.

Attribute WSS 0966, Morning Star, Max, and Bandit were the best performing yellow varieties.

Attribute WSS 0987, Tahoe, Summer Sweet 8101R, Extra Tender 275A, Gourmet Brand 378A, and 382A Xtra Tender Brand were the best performing white varieties. Variety 372A Xtra Tender Brand was the best early maturing white corn.

Attribute BSS 0977, Polaris, Candy Corner, and Shooting Star were the best bicolor varieties. Gourmet Brand 272A was the best early maturing bicolor variety.

The wet season reduced problems with husk coverage and tip fill. Consequently, most varieties performed very well.

Acknowledgments

The authors would like to thank the following persons for their hard work and assistance in the successful completion of this trial: Dave Lowry, Phillip Bush, Larry Blandford, Derek Law, Audrey Horrall, Barry Duncil, Courtney Bobrowski, Curtis Gregory, Justin Clark, Selvaprasanna Sanjeevijulian, Ashok Swaminathon, Saravanna Kannan, Kalyan Tangirala, Teerasak Tiamdao (Oa), Tanasit Laosomboon (Koh), Spencer Helsabeck, and John C. Clark.

Table 1. Plant characteristics and yield of supersweet corn cultivars, Lexington, Kentucky, 2003.
Cultivar	Seed Source1	Days to Maturity	Plant Stand2 (%)	Height to First Harvested Ear	Ease of Ear Harvest3 (1-5)	Yield (dozen ears per acre)
Attribute WSS 0987	SY	81	80	19	2.3	2645
Tahoe	SW/SY	81	94	23	3	2593
Attribute BSS 0977	SY	78	96	24	3.4	2256
Attribute WSS 0966	SY	79	91	24	2.8	2217
Morning Star	HR/HM	83	76	27	3.3	2139
Polaris	HM	81	90	22	2.4	2061
Rustler	HM	84	92	24	2.9	2048
Max (HMX 8392s)	HM	85	92	23	2.8	2022
Gourmet Brand 276A	ST	76	88	17	3.5	1997
Candy Corner	HM	76	92	23	3.6	1984
Shooting Star	HM	83	95	24	3.4	1945
Bandit	HM	80	86	26	3.5	1893
Gourmet Brand 272A	ST	72	95	10	3.5	1884
Summer Sweet 7631	AC	84	84	24	3.8	1841
Summer Sweet 8101R	AC	81	86	23	3.9	1815
Zenith	HM	81	91	28	2.4	1802
Extra Tender 275A	SI	75	95	17	3.9	1789
Gourmet Brand 378A	ST	78	94	17	3.5	1789
382A Xtra Tender Brand	SW	82	78	23	2.8	1776
WSS 9870	SY	78	95	18	3.4	1776
Summer Sweet 7650	AC		95	26	3.9	1737
Summer Sweet 8102R	AC		88	23	3.8	1724
Winstar	SY	82	94	26	3.4	1724
Boreal	SY	78	93	19	2.9	1698
Snowstorm	ST	82	94	23	3.1	1647
White Saturn	SW	75	91	19	3.2	1647
278A Extra Tender Brand	SI/SW	78	82	23	3.9	1634
372A Xtra Tender Brand	HR	72	92	12	2.7	1634
Camas	SY	84	96	26	3.1	1621
Tethys	SY/RU	77	97	19	3.6	1595
Mirai	SI		75	23	3.2	1530
Gourmet Brand 175A	ST	75	94	22	3	1517
Obsession	RU/ST	79	88	23	3.8	1517
Abco Brand Var. 946BC	AC		93	18	4.2	1491
First Class	SW	69	91	17	3.5	1452
Ice Queen	HR/HM	77	94	16	3.4	1452
Gourmet Brand 182A	ST	82	98	20	3.1	1439
6800R Hybrid Sweet	AC		97	16	4	1413
ACX 738W Hybrid	AC		81	13	4	1348
Gourmet Brand 277A	ST/RU/HR	76	87	19	1.8	1335
Millenium	SW	82	67	20	4	1335
First Snow	SW	72	88	16	3.5	1322
Eagle	RU	76	79	21	3.9	1296
Abco Brand Var. 945Y	AC		95	18	3.9	1284
282A Xtra Tender Brand	RU	82	84	21	4	1245
178A Xtra Tender Brand	RU	78	88	19	3.6	1206
GSS 9525	SY	77	87	15	3.3	1115
Gourmet Brand 177A	ST	77	90	17	3.3	1037
Waller-Duncan LSD (P = 0.05)						419
1 See Appendix for seed company addresses. 2 Plant stand is percentage emergence based on planting 100 seeds. 3 Ease of harvest: 1 = hard, 5 = easy.

Table 2. Ear characteristics of supersweet corn, Lexington, Kentucky, 2003.
Cultivar	Husk Coverage1 (1-10)	Ear Length (in.)	Ear Width (in.)	Tip Fill2 (1-10)	Kernel Color3	Row Straightness4 (1-10)
Attribute WSS 0987	8.8	7.3	1.8	9.3	W	7.5
Tahoe	8.8	7.9	1.9	8.5	W	7.5
Attribute BSS 0977	9.8