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Beginning in 2001 the Georgia Department of Agriculture mandated testing of new and existing Vidalia onion varieties under the supervision of the University of Georgia. This was prompted by the introduction of early maturing Japanese overwintering varieties, which were perceived to be more pungent than traditional varieties grown in the Vidalia district. The testing primarily focused on flavor and pungency (pyruvate analysis) to determine suitability as a Vidalia onion variety. Our testing compared varieties to an industry standard, initially variety Granex 33, which was later switched to `Savannah Sweet'. In almost all flavor and pungency tests differences were detected among the varieties, however, since the chosen standard variety usually fell within the middle of the tested range, there was no consistent rejection of a variety. If a different statistical approach had been used it would have been possible to reject several varieties over the course of testing. Using multiple comparison with the best (MCB), a modification of Dunnett's test where the best performing variety for a particular parameter becomes the standard, several varieties would have been excluded, but not all of the early Japanese overwintering types. Finally, in 2005 a consumer acceptance study was conducted with 30 consumers evaluating each of 49 varieties resulted in an LSD (5%) with no differences between the top 38 entries, which included several of the Japanese overwinter types. It is becoming clear that concerns over flavor with these early varieties are unfounded.

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Onions (Allium cepa) in southeastern Georgia are almost exclusively transplanted, with the associated high costs and labor requirements. This study was undertaken to evaluate direct-seeded onions as an alternative production method. This study evaluates variety, sowing date, and fertility on direct seeding short-day onions in southeastern Georgia. Sowing dates, early or mid-October (5 and 15 Oct. 2001 and 7 and 21 Oct. 2002), did not affect total, jumbo (≥3 inches diameter), or medium (≥2 inches and <3 inches diameter) yields. Late October sowing (29 Oct. 2001) did not produce sufficient stand or yield to warrant harvesting. Variety also had no affect on yield of direct-seeded onions. Seedstems (flowering), an undesirable characteristic, was significantly greater with the early October sowing date across all varieties compared with the mid- or late- October sowing dates. Neither variety nor sowing date significantly affected plant stand or plant spacing. Fertilization treatments of 150 or 195 lb/acre nitrogen (N) with various application timings and fertilizer sources did not affect total or medium yields. Jumbo yield was affected in only 1 year with calcium nitrate as the primary N source at 195 lb/acre total N having the highest yield, but did not differ from some treatments at 150 lb/acre N. In addition, fertilization treatments did not affect seedstems, plant stand, or plant spacing. Based on this study, we are recommending that growers should direct seed onions in southeastern Georgia in mid-October, plus or minus 1 week depending on field accessibility. In addition, current fertilizer recommendations for transplanted dry bulb onions should be followed, which includes 150 lb/acre N. This eliminates all of the cost and resources required for transplant production.

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