等行距密植下滴水量对不同抗旱性棉花品种群体生长特性的影响

Effects of Dripping Amount under Equal-Row Dense Planting on the Population Growth Characteristics of Different Drought-Resistant Cotton Varieties

【目的】研究等行距密植下精量制定棉花的田间水分管理制度分析机采棉花高效生产机理。【方法】选用抗旱性强的棉花品种新陆早22号(P_(22))和抗旱性弱的新陆早17号(P_(17))为参试品种,在等行距密植机采模式下,设3000(W_(1))、3900(W_(2))、4800(W_(3))m^(3)/hm^(2)3个处理水平,测定并分析不同处理下群体生长率(CGR)、净同化速率(NAR)、棉铃生长率(BGR)和叶面积载铃量(LAB)的变化。【结果】随滴水量的增加,棉花CGR、NAR、BGR、LAB均呈显著上升的趋势,其中P_(22)盛花期至盛铃后期的BGR在W_(2)和W_(3)处理间无显著差异,但均显著低于W_(1)处理;P_(17)的BGR在各生育时期均随滴水量的增加而显著增大。品种间,P_(22)的CGR、NAR、LAB在盛花期至盛铃后期比P_(17)高12.8%~18.2%、12.3%~12.9%、10.3%~12.2%,BGR在盛蕾期、盛铃期、盛铃后期则比P_(17)高11.9%~30.4%。盛铃后期的BGR与盛花期的BGR、LAB呈显著正相关、与盛花期的CGR、盛铃期的CGR、NAR、BGA均呈极显著正相关。【结论】等行距密植条件下,在3900 m^(3)/hm^(2)条件下选用抗旱性较强的棉花品种,有利于保持盛花至盛铃后期较高的群体生长率和棉铃生长率,促进光合产物向棉铃的分配与运输。

【Objective】To precisely formulate cotton field moisture management system under equal row spacing and close planting and reveal the efficient production mechanism of machine-picked cotton.【Method】The cotton varieties Xinluzao 22(P_(22))with strong drought resistance(P_(22))and Xinluzao 17(P_(17))with weak drought resistance were selected as the tested varieties,and in the machine-harvesting mode of equal row spacing,3,000(W_(1)),3,900(W_(2))and 4,800(W_(3))m^(3)/hm^(2)treatment levels were set to measure and analyze the crop growth rate(CGR),net assimilation rate(NAR),cotton boll growth rate(BGR)and leaf area loading boll(LAB)under different treatments.【Result】With the increase of dripping water,cotton CGR,NAR,BGR and LAB all showed a significant upward trend.Among them,there was no significant difference between W_(2) and W_(3) treatments in the BGR from P_(22)to the late blooming stage,but all were significantly lower than W_(1) Treatment:The BGR of P_(17)increased significantly with the increase of dripping water in each growth period.Among cultivars,the CGR,NAR,and LAB of P_(22) were 12.8%-18.2%,12.3%-12.9%,10.3%-12.2%higher than P_(17) from the full flowering stage to the late full boll stage,and the BGR was in the full bloom stage,full boll stage.In the later period,it was 11.9%-30.4%higher than P_(17).Correlation analysis showed that the BGR in the late blooming period was significantly positively correlated with BGR and LAB in the blooming period,and CGR,NAR,and BGA in the blooming period were all significantly positively correlated.【Conclusion】Under the condition of equal row spacing and close planting,the selection of drought-resistant cotton varieties under the condition of 3,900 m^(3)/hm^(2)is beneficial to maintain a higher population growth rate and boll growth rate in the late stage of blooming to full boll,and promote photosynthetic production to cotton bolls.