Nitrogen Requirements of Contemporary Cotton Cultivars
- FAR WEST
While a standard nitrogen recommendation for cotton has been 50-55 lbs. N/480 lb. bale, small-seeded, modern cotton cultivars might require less N than did those previously grown. A common experiment was conducted in ten states for two years. Lint yields responded positively to fertilizer N at only 11 of 20 sites. Total N increased plant height and number of fruiting nodes, decreased relative crop maturity, and increased seed weight, lint yields, and fiber strength up to a maximum of 147 lbs. applied N + pre-plant soil NO3-N/acre. Large seed size was associated with increased fiber strength and decreased gin turn out. No significant interactions of seed size and N rate were found for yield.