外源调环酸钙对盐碱胁迫下鼓粒期大豆光合特性及产量的影响OA

In this study,the salt-alkali tolerant variety Heihe 49 and the salt-alkali sensitive variety He-nong 95 were used as experimental materials.The pot experiment method was adopted,and different concen-trations(50,100,150 mg·L-1)of prohexadione-calcium(Pro-Ca)were set to explore the regulatory effect of Pro-Ca on the physiological characteristics and yield formation of soybean at the grain filling stage(R6 stage)under salt-alkali stress.The results showed that saline-alkali stress significantly inhibited the growth and devel-opment of soybean,resulting in a decrease of 23.0%to 44.2%in plant height,16.7%to 34.7%in stem diam-eter,and 21.4%to 27.4%in node number of main stem,a reduction of 17.4%to 38.9%in net photosynthetic rate,a decrease of 6.6%to 44.3%in antioxidant enzyme activity,and a reduction of 57.6%to 58.9%in grain yield.Exogenous spraying of Pro-Ca could effectively alleviate the damage to soybean caused by saline-alkali stress,and the effect was different between the two varieties,The treatment with 50 mg·L-1 Pro-Ca had the best effect on Heihe 49,increasing photosynthetic parameters by 14.8%to 87.3%,enhancing the activity of antioxidant enzymes by 17.1%to 66.3%,and led to the yield 65.3%of that of the control.The treatment with 100 mg·L-1 Pro-Ca had the best effect on Henong 95,increasing the photosynthetic efficiency by 52.1%to 89.3%,the activity of antioxidant enzymes by 12.8%to 86.4%,and led to the yield 78.8%of that of the con-trol.Overall,Heihe 49 showed higher salt-alkali tolerance than Henong 95,and Pro-Ca alleviated soybean sa-line-alkali stress by regulating the photosynthesis-antioxidant system,providing a theoretical basis and techni-cal reference for the rational application of Pro-Ca in soybean production in saline-alkali land.