|Frederick, James - CLEMSON UNIV.|
|McAlister Iii, David|
|Roof, Mitchell - CLEMSON UNIV.|
Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: November 3, 2003
Publication Date: November 3, 2003
Citation: BAUER, P.J., FREDERICK, J.R., MCALISTER III, D.D., ROOF, M.E. EFFECT OF PLANTING DATE AND N RATE ON COTTON [abstract]. AGRONOMY ABSTRACTS. 2003 CDROM. Technical Abstract: Early planting often results in chilling stress on young cotton (Gossypium hirustum L.) plants, which, through lower yield potential, may affect optimal N rate. Our objectives were to determine the effect of planting date and N rate on yield of genotypes differing in seedling vigor. Treatments in this two-year study were planting dates (mid-April, early May, and mid-May), N rates (45, 90, and 135 kg N/ha) and cultivar (DPL 458, DPL 655, DPL 5415, and DPL 5690). DPL 458 and DPL 5415 have relatively low seedling vigor compared to the other two cultivars. In 2000, lint yields (averaged over all cultivars) were 738 kg/ha for the mid-April planting date, 911 kg/ha for the early May planting date, and 1035 kg/ha for the late planting date (LSD0.05=158 kg/ha). In 2001, there were no differences among planting dates for lint yield (average yield was 1091 kg/ha). Averaged over planting dates, the 45 kg N/ha rate had lower yield than the other two rates in 2000, but there were no differences among N rates in 2001. Yield differences among the cultivars within planting dates and N rates were not related to relative seedling vigor. As for yield, fiber quality (length, strength, and micronaire) differences among planting dates and N rates were greater in 2000 than in 2001.