Seed Quality and Planting Date Effects on Cotton Lint Yield, Yield Components, and Fiber Quality

Poor quality cotton (Gossypium hirsutum L.) seed resulting from unfavorable growing conditions in seed production areas, complicates planting decisions for producers, particularly when higher-priced transgenic cultivars are involved. Studies were conducted to investigate how varying planting dates and genetic backgrounds affected the development, lint yield, and fiber quality for seed lots of varying quality or seed size. Twelve different seed lots of varying cultivars, seed germination rates, and seed sizes were planted at either an early April or early May planting date from 2002 through 2004 at Stoneville, MS. Seeding rate adjustments were made based upon the germination rate of the seed lots and seedling survival expectations for the two planting dates. Seedling emergence counts, dry matter partitioning, lint yield and yield components, and fiber quality data were collected each growing season. Although early planting reduced seedling emergence by 16%, lint yield increased 14%. Planting seed lots of varying germination rates or seed lots generated by blending seeds of varying germination for individual cultivars had essentially no impact on lint yield production and few effects on dry matter production or fiber quality. The larger seed size seed lot of PM 1218BR resulted in 17% more seedlings emerging than the small seed size lot, and that translated into 7% more lint yield for the large size seed lot. The overt negative consequences from inadequate stand establishment on lint yield production by using poor quality seed can mostly be avoided by adjusting the seeding rate to account for poorer germination rates or the poor emergence conditions associated with early planting.