Cooperative Extension Service
College of Agricultural and Environmental Sciences
The University of Georgia
George
Boyhan, Extension Horticulturist-Vegetables
East Georgia Extension Center
Nessmith-Lane Building, 2nd Floor
PO Box 8112
Georgia Southern University
Statesboro, GA 30460
912-681-5639 | 912-681-0376, Fax | 912-682-3481,
mobile
I know I've discussed triploid production in the past, but there have been some interesting developments in this area. Scott Nesmith, professor of horticulture at the University of Georgia, has done work on the actual amount of pollinizer plants required for triploid production. His work has suggested that only 20 percent of a field needs to be in pollinizer plants in order to maximize yields, with 5 feet between-row spacing. This is, as I've reported before, much less than our current recommendation of one row in three pollinizers (34%).
Another interesting development is the release of a short-vine (short-internode) cultivar by Seminis Seed called 'Companion.' They are recommending this cultivar be used as a pollinizer plant. Their system would involve planting the entire field to triploids and then interplanting the short-vine variety every second plant. This would mean a field would be planted 100 percent triploids with the pollinizer interplanted among them. The idea behind this is that the short-vine plants will not interfere with production, resulting in an increase in total triploid production.
Seminis's approach should result in increased triploid production on a per-area basis and, consequently, they are taking advantage of this potential. They will be charging for both the triploid seed and the pollinizer seed. In addition, they plan on charging a technology fee.
While at Auburn University, I remember growing watermelons that were very similar to the Companion variety. Short-vine plants like this have been around for quite a while, with several varieties released and marketed to homeowners in particular for limited space production. There have also been ideas floated of using mechanical harvesting with short-vine watermelons.
Sunseed is also working on a similar system with a cultivar that will have a citron-like fruit that is not edible. This variety presumably has been selected to produce a lot of male flowers. This variety is currently called SP-1 (super pollinizer 1) and should be available in another year or two.
I have had the opportunity to work with Seminis's short-vine pollinizer. I looked at the plant interplanted every second and every fourth plant, and there was no difference in production (see table below). This further reinforces Scott's work on the number of actual pollinizers required.
| Evaluation of short-intermode pollinizer | |||
| Treatments | Yield (lbs/plot) | No. of fruit/plot | |
| Every Second Plant | 240 | 15 | |
| Every Fourth Plant | 268 | 18 | |
| ---------- | P>F | 0.658 | |
As in the past, we had a large Vidalia onion variety trial this past years. Samples of all the onions were transported to the Vidalia Lab in Tifton for storage. The top five performers with the highest percentage of marketable yield after 4.5 months of CA storage were Georgia Boy (DPS 1032), RCX 6043, Sweet Melissa, Numex Chaco and PS 7092.
This year, we also evaluated the onions two weeks after removal from storage to assess their ability to move through the marketing stream. After two weeks at room temperature, the top five performers with the highest percent marketable yield included Georgia Boy, SSC 6372, Sapelo Sweet, Ohopee Sweet and RCX 6043. Numex Chaco dropped to ninth place and SSC 6372 moved from seventh to second place.
Overall, all of the varieties did well with none having less than 70 percent marketable yield immediately after removal from storage. After two weeks at room temperature, they did not do quite as well. Savannah Sweet, Mr. Buck (DPS 1033), Cyclops and Sweet Melody all had marketable yields below 60 percent. Interestingly, Sweet Melody, which in the previous two years has stored well with marketable yields consistently in the top five, this year was the worst after two weeks at room temperature, with a marketable yield of only 38 percent.
The 2001-2002 season was particularly bad for growers with high incidences of Stemphyllium. At the Vidalia Farm, we did not have this problem but were plagued with warm-season bacterial diseases, so we harvested onions earlier than perhaps we would have in a normal season. Based on the incidence of bacterial disease, we expected to see a high incidence of unmarketable onions coming from storage. This was not the case and may suggest than early harvest may help stored onions. Other work we have done with harvest effects on stored onions have also indicated this may be the case.
| Cultivar | Seed Company |
Days
after Removal from CA Storage |
|
| 0 | 14 | ||
| Georgia Boy (DPS 1032) | D. Palmer Seed | 97% | 89% |
| SSC 6372 F1 | Shamrock | 94% | 89% |
| Sapelo Sweet (DPS 1039) | D. Palmer Seed | 93% | 88% |
| Ohopee Sweet (DPS 1024) | D. Palmer Seed | 95% | 87% |
| RCX 6043 | Skunseeds | 96% | 87% |
| Sweet Advantage | D. Palmer Seed | 92% | 86% |
| Sweet Melissa | Sunseeds | 95% | 84% |
| PS 7092 | Seminis/Petoseed | 95% | 84% |
| Numex Chaco | Lockhart | 95% | 84% |
| Sugar Belle F1 (SSC 6371) | Shamrock | 90% | 83% |
| Nirvana (1027) | Sunseeds | 92% | 81% |
| Sweet Vidalia | Sunseeds | 92% | 81% |
| 99C 5092 | Sakata | 89% | 79% |
| EX 07592000 | Seminis/Asgrow | 92% | 79% |
| WI-609 | Wannamaker | 91% | 79% |
| EX 07592001 | Seminis/Asgrow | 91% | 79% |
| Southern Belle | D. Palmer Seed | 86% | 77% |
| Granex 33 | Seminis/Asgrow | 88% | 77% |
| Southern Honey | D. Palmer Seed | 90% | 76% |
| Liberty | Bejo Seed Co. | 93% | 75% |
| Pegasus | Seminis/Asgrow | 88% | 75% |
| EX 19013 | Seminis/Asgrow | 93% | 73% |
| RCX 5195-1 | Sunseeds | 86% | 72% |
| Granex Yellow, PRR Asgrow | Seminis/Asgrow | 88% | 72% |
| Rio Bravo | Sunseeds | 90% | 72% |
| Yellow Granex, PRR Sunseed | Sunseeds | 86% | 68% |
| WI-315 | Wannamaker | 82% | 67% |
| Savannah Sweet | Seminis/Asgrow | 88% | 59% |
| Mr. Buck (DPS 1033) | D. Palmer Seed | 83% | 57% |
| Cyclops (XP 6995) | Seminis/Asgrow | 83% | 54% |
| Sweet Melody | Sunseeds | 71% | 38% |
| - | |||
| CV | 9% | 20% | |
| R2 | 0.392 | 0.569 | |
Adjusted
LSD (p 0.05) |
12.3% | 19.3% | |
Well, I've spent the past two months without my computer. My computer went on vacation three times in three weeks to California for repair. After they got through with it, it didn't work at all. I hate to admit it, but I use an Apple. On the upside, I got a new computer out of the deal, which runs faster than the last one.
Well, again I'm behind schedule with the newsletter, but I plan on turning right around and sending out the February issue.
Regards.