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Sweet Onion Variety Trial, NFREC - Quincy Spring 2008.
By, Dr. Stephen Olson, Professor, North Florida Research and Education Center – Quincy, FL
Sweet (short-day) onions are a relatively minor crop in Florida. Production exists as both dry bulbs (mature) and green tops (immature). Limited production exists throughout the state. The biggest deterrent for increased production is from competition from established markets in south Texas and middle Georgia areas (Vidalia). However, the potential exists for expanding production, especially in the areas of local sales and direct marketing.
The objective of this trial was to evaluate the performance of sweet onion varieties under northwest Florida conditions.
The transplants for this trial were produced from field beds at the NFREC, Quincy. Twenty one entries were seeded on 27 Sept 2007. Three of the entries (‘Red Rhone', ‘Lambada' and ‘Mata Hari') were red onions. Seed were planted at rate of about 30 seed per ft into rows spaced 12 inches apart. Preplant fertilization of seedbeds was 30-40-40 lbs/A of N-P2O5-K2O. Dacthal W 75 was applied over the top at 10 lb/A after seeding. Seedbeds were top dressed once with 34 lbs N/A. Entries were transplanted into the production field on 7 Jan 2008. Soil type was an Orangeburg loamy fine sand. Total fertilization was 160-80-140 lbs/A of N-P2O5-K2O. Production scheme was 3 rows spaced 15 inches apart under a 6 ft tractor and in-row spacing was 4 inches (65,340 plants/A). Goal 2XL at 2 pts/A was applied on soil surface before transplanting. Registered pesticides were applied as needed to control pests.
Entries were harvested as they matured, where maturity is defined as when about 50% or more of the tops of an entry had fallen down naturally. Bulbs were lifted, allowed to dry for a few hours and tops and roots removed. Bulbs were then placed in bushel baskets and dried for 72 hours at 100o F in large drying rooms. After drying time was complete, onions were removed, allowed to cool down and graded. Grading consisted of discarding culls (small onions, splits, off color and decayed) and sizing into medium (1.5-2 inches), large (2-3 inches) and jumbo (>3 inches) categories. Bulbs were then weighed and counted.
Harvest occurred from the period of 22 April to 16 May. Total yields ranged from 955 50 lb bags/A for ‘WI-3115' to 333 50 lb bags/A for ‘Caramelo' (Table 1). Eight other entries produced total yields equal to ‘WI-3115'. Yields were good to excellent in 2008. Growing conditions were good. ‘Don Victor' produced the largest bulb at 14.8 oz and ‘SSC 1535' produced the smallest at 8.9 oz. Percent marketable bulbs ranged from a low of 35.7 % for ‘Caramelo' to a high of 96.4 % for ‘WI-301'. Percent bolting ranged from a high of 44.7 % for ‘Sweet Vidalia' to <1% for ‘WI-301', ‘Red Rhone', ‘Don Victor' and ‘Gobi'. Days to harvest from transplanting ranged 106 days for ‘Sweet Deal' and ‘Honeybee' to 127 days for ‘Don Victor', ‘Mata Hari', ‘Lambada', and ‘Caramelo'.
Table 1. Sweet Onion Variety Trial Spring 2008. NFREC, Quincy.Entry |
Source |
Marketable Yield |
Marketable (%) |
Bulb Wt. (oz) |
Bolts (%) |
Day to harvest |
|
|
|
Jumbo |
Total |
|
|
|
|
WI-3115 |
Wannamaker |
898 aZ |
955 a |
91.3 a-c |
12.4 b-e |
2.3 gh |
113 |
WI-301 |
Wannamaker |
796 ab |
860 ab |
96.4 a |
11.0 c-g |
0.7 h |
113 |
WI-131 |
Wannamaker |
797 ab |
854 a-c |
93.9 ab |
11.5 b-g |
3.2 f-h |
113 |
Red Rhone |
Wannamaker |
695 a-c |
825 a-d |
80.7 a-e |
10.8 d-h |
0.1 h |
130 |
Kalahari |
Nunhems |
754 a-c |
799 a-d |
76.5 b-f |
13.1 ab |
3.0 f-h |
120 |
Prowler |
Nunhems |
748 a-c |
787 a-e |
87.4 a-d |
12.3 b-e |
5.8 e-h |
116 |
Sugar Belle |
Shamrock |
707 a-c |
753 a-e |
76.5 b-f |
12.0 b-f |
7.6 e-g |
120 |
NUN 1500 ON |
Nunhems |
708 a-c |
749 a-e |
70.0 d-f |
12.2 b-e |
3.6 f-h |
123 |
Don Victor |
Nunhems |
708 a-c |
749 a-e |
62.2 f-h |
14.8 a |
0.8 h |
127 |
Sweet Deal |
Shamrock |
658 bc |
722 b-e |
86.6 a-d |
10.7 e-h |
3.2 f-h |
106 |
Honeybee |
Shamrock |
624 b-d |
685 b-e |
90.1 a-c |
10.1 f-h |
8.2 e-g |
106 |
Nirvana |
Nunhems |
646 bc |
679 b-e |
70.5 d-f |
12.1 b-f |
3.1 f-h |
120 |
Honeycomb |
Shamrock |
612 b-d |
640 c-f |
89.9 a-c |
11.3 b-g |
23.7 b |
123 |
Gobi |
Nunhems |
571 cd |
634 d-f |
74.4 c-f |
10.6 e-h |
0.7 h |
116 |
SSC 1535 |
Shamrock |
540 cd |
617 d-f |
83.7 a-d |
8.9 h |
9.3 ef |
113 |
Mata Hari |
Nunhems |
553 cd |
579 ef |
64.9 e-g |
12.9 bc |
15.8 cd |
127 |
Sweet Caroline |
Nunhems |
431 de |
446 fg |
50.0 g-i |
12.8 b-d |
19.0 bc |
120 |
Lambada |
Nunhems |
341 e |
378 g |
47.7 hi |
11.1 b-g |
11.7 de |
127 |
Goldeneye |
Seminis |
340 e |
360 g |
51.4 g-i |
11.2 b-g |
22.1 b |
123 |
Sweet Vidalia |
Nunhems |
305 e |
343 g |
77.3 b-f |
9.9 gh |
44.7 a |
116 |
Caramelo |
Nunhems |
320 e |
333 g |
35.7 i |
11.6 b-g |
8.4 e-g |
127 |
