Submitted to: Agronomy Abstracts
Publication Type: Abstract Only
Publication Acceptance Date: March 15, 1996
Publication Date: N/A
Technical Abstract: Management practices that cause boll development to occur later in the season, such as double-cropping and reduced early-season insect control, are being developed for SE USA cotton (Gossypium hirsutum). Our objective was to compare seeding date and canopy position effects on cotton fiber properties. In 1995, first sympodial bolls from the first (lower canopy) and fourth (upper canopy) week of flowering in 2 May and 31 May seeding dates were evaluated. Seedcotton yield was 2064 kg/ha for the early seeding date and 1521 kg/ha for the late. For both seeding dates, canopy photosynthesis declined at a rate of 0.4 umol CO2/m/s/day between 20 and 60 days after first flower. The upper bolls that flowered as canopy photosynthesis was declining had lower boll growth rates, micronaire, and fiber length than the lower bolls, regardless of seeding date. Motes/ boll were unrelated to canopy photosynthesis as motes were higher for bolls that flowered in early August than bolls that flowered in mid-July or late August.