| With the method of limited irrigation in treatments: no irrigation (A, CK), irrigation at 337.5 m3/hm2(B), irrigation at 675 m3/hm2(C) and irrigation at 1 350 m3/hm2(D), the effect of the irrigation on the yield formation of transgenic pest-resistant cotton was studied. The results indicated that the amount of dry matter per plant in seed increased by 23.4%61.9%, the lint yield increased by 16.8%～45.3% compared with those of the control, both boll number and weight increased, and boll quality improved. The optium amount water was 675 m3/hm2in each irrigation, which could make the effect of irrigation attain 0.57 kg/m3, but when it was raised to 1 350 m3/hm2the effect of irrigation reduced to 0.21 kg/m3. The key to increase the yield was the increased boll numbers both in suitable seasons for cotton growth and at advantageous node of cotton plant. |