Abstract:

【Objective】 Dry matter accumulation and nutrients uptake were characterized in hybrid cotton (Gossypium hirsutum L.) cultivars, which provided theoretical basis in making measures for high yield fertilization according to cotton growth and development characteristics.【Method】 Biaoza A1 and Xinluzao 43, with the conventional cultivar Xinluzao 13 as control, randomized block design was made under field conditions and routine analysis of dry matter, nitrogen, phosphorus and potassium was done at laboratory.【Result】The quantities of dry matter accumulated and nitrogen, phosphorus, potassium uptake by the two hybrid cultivars (Biaoza A1 and Xinluzao 43) were increased by 20.6% and 15.5%, 16.1% and 10.5%, 16.4% and 11.4%, 21.0% and 18.5%, respectively, as compared with the control. The amounts of dry matter accumulated and nitrogen, phosphorus, potassium uptake by buds, flowers and bolls of the two hybrid cultivars were increased by 20.7% and 15.4%,16.9% and 10.7%, 18.1% and 11.5%, 20.7% and 18.3%, respectively, compared with the control. Higher amounts of dry matter and nutrients were consistently distributed in the leaves of hybrid cultivars, and were also recorded in the stems at the first and middle periods, and in the buds, flowers and bolls at the late stages as compared with the conventional cultivar (control). In the late growing period the nutrients uptake rate in stems and leaves of hybrid cultivars was lower than the conventional cotton cultivar, but the nutrients uptake rate in buds, flowers and bolls was higher in hybrid cotton than in the conventional cotton. 【Conclusion】 The amounts of dry matter accumulation and nutrients uptake in the two hybrid varieties used were significantly higher than those in the conventional variety. The whole uptake of N, P2O5 and K2O in Biaoza A1 and Xinluzao 43 were 302.7 and 288.1 kg•hm-2, 138.2 and 132.3 kg•hm-2, and 459.2 and 449.7 kg•hm-2, respectively.

Key words: hybrid cotton, dry matter, nitrogen, phosphorus, potassium