为明确障碍型冷害对不同播期棉花花铃期农艺生理指标的影响,对分期播种的盆栽供试样品棉花,当其达到花铃期时,应用植物生长室实施低温模拟试验,研究障碍型低温冷害对不同播期棉花叶片、蕾和铃脱落情况及叶绿素含量和光合速率的影响.棉花在花铃期遭受障碍型低温冷害后,会比对照脱落较多叶片、蕾和铃,第一播期整个过程其脱落率比对照分别多58%、55%、10%;同时,功能叶的叶绿素含量和光合速率在遭受低温处理后一直呈下降趋势,并没有随生长环境的恢复而出现明显回升,第一播期自然生长的棉花SPAD值和净光合速率值较低温处理的分别大11%、170%.障碍型冷害对花铃期棉花的影响受棉花前期生长所接受热量的多少有关,受相同程度的低温冷害后,前期生长所接受热量多的棉花在该发育期内抵御低温逆境的能力比受热量少的棉花强.%In order to protect the cotton yield,the paper investigated the effects of severe sterile-type cold injury on the cotton agronomical and physiological indexes during different flowering and boll stages.The simulated experiment at low temperature was conducted in the plant growth chamber at the Wulanwusu Agro-meteorological Experiment Station in the Cotton Belt of Shihezi.The experiments showed that:in the cotton boll stage after the severe sterile-type cold injury,leaves,buds and bolls of the first sowing period fell off 58%,55% and 10% more,respectively than those of the control.And when the environment stress relieved,the physiology function quickly recovered to a certain degree (the abscission rate reduced).At the same time,the chlorophyll content and photosynthetic rate of the function leaves kept declining after the low temperature experiment,which were not improved with the recovery of growth environment.The val-ues of SPAD and net photosynthetic rate of naturally growing cotton of the first sowing period were 11%and 170%,respectively higher than those of the cotton treated by low temperature.The study also found that the physiological characteristics of the cotton in the blooming period were affected by the early acceptable amount heat during the growth stage.The values of the SPAD and Pn of the cotton that accepted more heat were higher than others and the ability to resist low temperature adversity was relatively stronger,namely,this kind of cotton had lower abscission and higher Pn after suffering the same degree of cold injury.
展开▼
