印度梨形孢促进棉花幼苗生长及诱导提高苗期抗旱性研究

Growth promotion and tolerance improvement to drought stress of cotton seedling conferred by Piriformospora indica

以干旱敏感型陆地棉栽培种沙洋505-3A为材料,二叶期接种印度梨形孢,20 d后测定株高、茎粗、叶面积、净光合速率、胞间CO 2浓度、气孔导度、蒸腾速率等指标,研究印度梨形孢对棉花幼苗的促进生长作用。在自然干旱和15%、20%PEG6000模拟干旱处理后测定株高、茎粗、根系生长参数、叶片温度、叶片反射率和MDA含量。结果表明:接种印度梨形孢后,棉花幼苗株高、茎粗、叶面积分别显著提高32.4%、15.8%、20.5%;净光合速率(P n)、气孔导度(G s)、胞间CO 2浓度(C i)、蒸腾速率(T r)分别提高了29.1%、55.9%、20.1%和51.1%;干旱处理后,接种印度梨形孢植株的株高、茎粗分别降低14.1%和5.3%;不接菌植株分别降低23.3%和8.7%。接菌植株总根长、总根表面积、根体积、根尖数分别增加9.6%、9.9%、3.8%和21.3%;不接菌植株分别增加11%、27.7%、12.2%,根尖数降低5.2%;接菌植株叶温和MDA含量分别上升0.34℃和9.9%,不接菌植株分别上升0.97℃和19.1%。说明接种印度梨形孢可以促进棉花幼苗生长并且通过调节植株根系形态和维持正常的生理代谢来诱导提高棉花的抗旱性。

A drought sensitive cotton variety,Shayang 505-3A,was inoculated with Piriformospora indica for the experiment,and the plant height,stem diameter,leaf area,net photosynthesis rate(P n),stomatal conductance(G s),intercellular CO 2 concentration(C i),and transpiration rate(T r)were measured at 20 days of the growth.The plant height,stem diameter,root parameters,leaf temperature,leaf reflectance and MDA content were collected after the treatments of natural drought and PEG-6000(15%and 20%)induced drought.The results showed that the plant height,stem diameter,leaf area of cotten seedlings were significantly increased by 32.4%,15.8%and 20.5%after inoculated with Piriformospora indica,and P n,G s,C i and T r were increased by 29.1%,55.9%,20.1%and 51.1%,respectively.After drought treatment,the plant height and stem diameter of plants inoculated with Piriformospora indica decreased by 14.1%and 5.3%,respectively,while that of non-inoculated plants decreased by 23.3%and 8.7%,respectively.The total root length,total root surface area,root volume and root tip number increased by 9.6%,9.9%,3.8%and 21.3%,respectively,while the non-inoculated plants increased by 11%,27.7%,12.2%,and the number of root tips decreased by 5.2%.Moreover,the leaf temperature and MDA content increased by 0.34℃and 9.9%,respectively,while the non-inoculated plants increased 0.97℃and 19.1%,respectively.The results indicated that inoculation with Piriformospora indica promoted the growth of cotton seedlings and induced the drought tolerance of cotton by improving morphology of plant root and maintaining normal physiological metabolism.