Evaluation of Sweet Corn Varieties at Two Grower Locations in Ohio

Robert J. Precheur, Jim Doran, David Schacht, Department of Horticulture and Crop Science, Grower Cooperators: New Albany, OH, Canal Winchester, OH.

Sweet Corn is Ohio's number one fresh market vegetable with between 15,000 to 17,000 acres planted depending on the year. In the US, Ohio ranks 6^th in fresh market sweet corn production. Sweet corn is produced throughout OH, in the southeast along the Ohio River, in many counties around Cincinnati, and also throughout central and northern OH.

Objectives

To identify sweet corn cultivars with good emergence, high marketable yield and excellent quality under OH growing conditions.

Methods

SE varieties were planted on May 7 in New Albany. At Canal Winchester, SE varieties were planted on May 11, 2008. Four bi-color SH2 varieties were planted on May 22, 2008 and 1 white SH2 variety on June 2 in Canal Winchester. Heavy, record rains in late May and June extensively delayed SH2 plantings in New Albany. Plots consisted of either: 4, 6 or 8 row blocks, 30 in apart and approximately 500 or 1000 ft long depending on location. In row spacing averaged 9 inches in Canal Winchester and 11 inches in New Albany. The middle two rows (total 20 linear feet) at three random locations in the block were used for yield data. Data collected included early plant vigor, plant and ear characteristics, and marketable yield. Sweetness was determined by a purely subjective evaluation of raw eating quality. Each variety was also evaluated for percent germination using the saturated salt accelerated ageing test (see Table 1) and at ten different temperatures on the thermo-gradient table (see Summary Table 2). Complete thermo gradient results, will be available at the VegNet website: http://vegnet.osu.edu

Results

Early May weather allowed for early planting and good germination but was followed by a period of cool and record wet weather. In the bicolor se’s, Sparkler and BC0805 had good early plant vigor 2-4 weeks after emergence. Good field conditions were favorable for rapid germination, but cold wet weather delayed development of early May plantings.

In the se’s, BC 0805, Sparkler and Valiant had the best yield and good eating quality at both locations. In the white se’s, WH0809 yields were good in Canal Winchester but much lower at New Albany. The eating of WH0809 was preferred over Frosty having tender sweet kernels .

Maturity for the sh2’s were either on schedule or ahead of schedule as temperatures warmed up in the summer. Yields were very good and the highest yielding bicolor sh2’s were: Mirai 77747 with very good eating quality. Holiday (augmented SH2) was second followed by BSS0982 and Mirai 350BC. Symmetry is a new white (augmented SH2) that had high yields and very good quality. As I previous years, for a yellow sh2, Mirai 130 was productive, had very good eating quality coming in early at 72 days. Some pictures are available below after the tables.

The SSAA Test

The accelerated aging test is a common and important seed vigor indicator for many large-seeded crops, but its utility for sweet corn (Zea mays L.) evaluation may be limited because of the anatomical and compositional differences among su, sh2 and se genotypes. The recent use of saturated salts in accelerated aging tests to reduce water uptake, microflora growth, and slow seed deterioration (Jianhua and McDonald, 1996) may also be useful in more accurately testing sweet corn genotypes. Pericarp damage and pathogen levels in (or on) sh2 seed are especially troublesome (Borowski et al., 1991; Parera et al., 1996). Use of a saturated salt accelerated aging (SSAA) test is to more accurately evaluate sweet corn seeds. The SSAA test should (1) reduce water uptake, (2) minimize microflora growth, and (3) slow overall seed deterioration, thereby allowing a more precise and repeatable measurement of sweet corn seed vigor.

Table 1. Saturated salt accelerated aging (SSAA) results for sweet corn germplasm - 2008

ID #	Cultivar	Color	Genotype	Days	% germination	comment
	SE's
1	Quickie	Bi	se	68(1175)	99	very moldy
2	BC0808	Bi	se	73	92.5
3	Valiant	Bi	se homoz	77	24.5	very moldy
4	Sparkler	Bi	SE synergystic	78	99
5	BC0805	Bi	se	82	95.5
6	Frosty	W	se homoz	75(1275)	80
7	WH0809	W	se	80	79	very moldy
	SH2's
8	77747(Mirai)	Bi	sh2	76	82.5
9	Mirai 350BC	Bi	sh2	78	82
10	BSS0982	Bi	sh2	80-82	57
12	Holiday	Bi	aug sh2	84	22.5
13	Symmetry	W	aug sh2	84(1428)	70.5
14	Mirai 130Y	Y	sh2	72	47.5

Table 2. Summarization of 2008, Sweet Corn Cultivars on The Thermo-Gradient Table

					Percent Germination
	Temperature Range				12-16^oC 57 - 61 ^oF				18-20^oC 64 - 68 ^oF				22-30^oC > 72 ^oF
	Days on Table				3	5	7	10	3	5	7	10	3	5	7	10
ID #	Variety	Color	Type	Days
	SE's
1	Quickie	Bi	se	68(1175)	0	15	33	50	2	65	97	98	55	94	97	98
2	BC0808	Bi	se	73	0	5.5	21	60	0	60	82	31	53	97	100	100
3	Valiant	Bi	se homoz	77	0		3	19	0	13	52	72	23	75	83	83
4	Sparkler	Bi	SE synergystic	78	0	3.3	13	20	0	35	85	92	29	90	95	97
5	BC0805	Bi	se	82	0	13	28	49	10	90	100	97	81	99	99	99
6	Frosty	W	se homoz	75(1275)	0	7	43	60	2	77	95	95	65	96	99	99
7	WH0809	W	se	80	0	4	41	55	0	83	98	98	51	96	97	98
	SH2's
8	77747(Mirai)	Bi	sh2	76	0	2	10	20	0	37	62	87	51	91	93	95
9	Mirai 350BC	Bi	sh2	78	0	12	19	39	2	60	82	95	69	97	100	100
10	BSS0982	Bi	sh2	80-82	0	2	14	36	0	30	68	83	27	89	93	93
12	Holiday	Bi	aug sh2	84	0	0	12	21	0	35	72	63	45	79	87	85
13	Symmetry	W	aug sh2	84(1428)	0	6	22	32	2	52	70	90	68	95	97	97
14	Mirai 130Y	Y	sh2	72	0	1	6	11	0	35	52	63	36	78	87	90

1. Averaged percent germination for variety #3, is from 2 replications only. All other averages are from 3 replications.

SE Varieties (Bi-color)

BC 0808	Valiant
Sparkler	BC0805
SE’s WHITE
Frosty	WH 0809
SH2’s - Bicolor
77747 (Mirai)	Mirai 350BC
BSS 0982	Holiday (augmented SH2, from 2007)
Symmetry (White-augmented SH2)	Mirai 130Y (Yellow SH2)