| In this paper, the effects of drought\|resistance chemicals on growth and development under high temperature and drought stress in cotton were discussed. Different types of drought\|resistance chemicals of fulvic acid potassium (K1), plant protein immunizers (K2), water\|soluble fertilizer containing amino acid (K3) were sprayed at bud stage (A1), bud and flowering stages (A2), flowering stage (A3) in this study. Agronomy parameters, dry matter, leaf area index, root\|shoot ratio, root morphology index, yield, and quality were observed across treatments and cultivars to decide the optimal drought\|resistance chemicals at different spraying periods. The results showed that the plant height, the number of sympodials, buds, flowers and leaf age of K1A1, K1A3 and K3A1 were 70.2, 68.8, 68.9 cm, 7.9, 7.7, 7.7, 5.9, 5.7, 5.9, 1.3,1.3 and 1.3, 13.7, 13.9, 13.7, respectively, which were significantly different from the CK and were better than other combinations. The dry matte mass of K2A3 was 4.3 t·hm-2 and leaf area index of K2A1 was 2.8. The root\|shoot ratio of K1A1, K3A2 were 0.156 and 0.156, respectively, which were significantly different from the CK and were better than other combinations. The root length, root area of K1A1 was 36.9 mm, 0.63 mm2 and the root diameter of K2A1 was 0.95 mm, the root volume and root area of K3A3 were 26.9 cm3and 0.63 mm2, respectively, which were significantly different from the CK and were better than other combinations. The combinations of K1A1, K2A3 and K3A1 had the highest seed cotton yield and the best yield composition factor ratio, with 5 876.4, 5 866.3, 5 968.3 kg·hm-2, respectively. The upper half mean length, breaking tenacity, micronaire, uniformity and elongation of K1A1 and K3A1 were 31.6, 31.8 mm, 37.2, 37.1 cN·tex-1, 4.0, 3.9, 87.0%, 87.5%, 7.1%, 7.1%, respectively. Except the micronaire value was slightly lower than CK, the other cotton fiber quality indexes of K1A1 and K3A1 combination treatment were higher than those of other treatments, and the cotton fiber quality was better. To sum up, the indicators under the combination treatment of K1, K2, K3 drought\|resistance chemicals at bud stage (K1A1, K2A1, K3A1) all performed well, which can serve as the theoretical basis for large\|area application of drought resistance and water saving in drip irrigation cotton under different needs. |