| Summary: | Four field experiments were established in 1988 in Arizona to evaluate the effects of banded phosphorus (P) fertilizers on cotton. 2 sites involved upland cotton (Gossypium hirsutum L.) and 2 sites with pima (G. barbadense L. var Pima S-6), with 1 of each located near Marana, AZ (Vinton Anthony sandy loam). A site with 1 of each kinds was also located near Coolidge, AZ (Mohall sandy loam). At the Marana studies, P was applied 6 inches directly below the zone of seed placement at the time of listing and at the Coolidge sites, P was applied 6 inches below and 2 inches to the side of the zone of seed placement after listing but before planting. In all cases, the P source was 10-34-0 at rates of 0, 30, and 65 lb. P₂O₅ acre⁻¹. At the Marana location, a treatment of banded 10-34-0 at 30 lb. P₂O₅ acre⁻¹ plus a foliar application of 10 lb. P₂O₅ acre⁻¹ (early bloom) as 10-34-0 was included in both the upland and the pima experiments. Plant measurements for plant height, flower numbers, node numbers, boll numbers, and nodes to first fruiting branch were taken to evaluate plant response throughout the season. Plant tissue samples were also taken for leaf petiole PO₄-P and leaf blade total P analysis. Lint yield measurements were also taken. No statistically significant (P < 0.05) differences were found among any of the treatments for any of the measured parameters, except in the petiole PO₄-P levels from the upland study at Coolidge on the second sampling date.
|
|---|
