Synopsis Irrigation increased the yield of cotton approximately 1 bale per acre but water applied before blooming had no beneficial effect. Maturity was delayed and the peak of fruiting was extended 2 weeks by irrigation. Shedding was significantly decreased and boll size was significantly increased. Lint quality was improved in most cases by proper moisture conditions.

Utilization of seed proteins from cotton (Gossypium hirsutum L.) as an ingredient of food products for nonruminant animals may provide producers with a salable seed commodity in addition to oil and meal. It was important to confirm and more fully establish the effects of N fertilization on cottonseed protein concentration and protein quality (amino acid composition). In order to achieve this, seed was collected in 1976 from a N fertility experiment which had been established with the same N rates the previous 2 years. Cotton (‘DES 56’ was grown on a Dundee silt loam soil, a fine‐silt, mixed, thermic, Aeric Ochraqualfs, with four replications. The experimental design was a split‐plot with N rates (67, 90, 112, 134, and 157 kg ha‐1) as the main plots and time of application (preplant, 1/2 preplant‐1/2 sidedressed, and sidedressed) as subplots (the same plots received the same treatment each year). We measured yield of seed cotton, seed N concentration and amino acid composition. In 1976 the higher N rates increased seed N concentrations from 6.05% N up to 6.60% N, whereas time of application had no effect. Application of N decreased lysine and increased arginine concentration, whereas histidine, serine, tyrosine and phenylalanine were affected by time of application. Glycine was affected by both rate and time of application. Correlation of seed N concentration with amino acid concentration showed that arginine, cysteine and proline were positively related and that lysine, histidine, and threonine were negatively related to seed N. The effects produced by application of fertilizer N to cotton in a field situation result in seed N and amino acid concentration similar to results reported previously in an unusual field situation and allow for better prediction of N effects on cottonseed composition.