障碍型冷害对石河子棉区花铃期棉花生长的影响研究

为了明确棉花主栽品种耐冷性及障碍型冷害的量化指标，达到及时预报，减轻损失的目的。运用智能人工气候箱，在新疆石河子棉区乌兰乌苏农业气象试验站内，于2003-2005年进行低温冷害模拟试验，研究花铃期棉花在经受不同范围和时长的低温后，其植株的受害程度。结果表明，低温处理之后，棉花的叶片、蕾和幼铃都出现异常脱落，经过11.5~18.5℃处理2~4天的其叶片在第8天后才开始异常脱落，其减少率≥35%，并呈持续减少的趋势，而其蕾、幼铃在第6天后就开始异常脱落，减少率≥55%；经过11.5~22.5℃处理2~4天其叶片减少率≤25%，并在处理后的第18~23天基本保持稳定，其蕾、幼铃减少率≥70%。说明花铃期棉花在受冷害之后，其蕾、幼铃先于叶片出现异常脱落，其减少率大于叶片，经过2种相同最低温度不同最高温度的处理，温度日较差小的叶片减少率较高。

Experiments and Studies about Effect of Obstacle Cold Disaster on Cotton During the Flowering and Boll Stages in the Cotton Region of Shihezi

For the purpose to supply the quantitive index of severe cold disasters and cold resistance on cotton, the simulated experiment of low temperature, applying intelligent artificially climate box, was carried out in Wulanwusu Agro-meteorological Experiment Station in Xinjiang during 2003-2005. The responses of cotton at flowering and boll-forming stages to low temperature and duration of the low temperature were studied. The results showed that, the leaf, bud and bell of cotton broke off abnormally after supplying low temperature. The leaf began to break off on the eighth day, and the reduced rate was more than 35% in the treatment of low temperature 11.5-18.5℃ for 2-4 days, but the bud ＆ bell was on the sixth day and 55% respectively in the same treatment. The reduced rate of leaf was less than 25%, and the leaf numbers was stable on the 18th to 23rd,and the reduced rate of bud ＆ bell were all more than 70%, in the treatment of low temperature 11.5-22.5℃ for 2-4 days. The comprehensive analysis showed that, the response of bud and bell to suffer the same low temperature range were more sensitive than the leaf, and the reduced rate were more serious than the leaf during the flowering and boll-forming stages. The two treatments with the different minimum temperature and the same maximum temperature, the smaller diurnal temperature the higher decrease rate of leaf.