模拟酸雨对棉花子叶圆片细胞膜透性的影响

EFFECT OF THE SIMULATED ACID RAIN ON THE CELL MEMBRANE PERMEABILITY OF COTTN COTYLEDON DISC

研究了棉花子叶细胞膜透性在酸雨伤害过程中的胁迫强度、胁迫时间(胁程)和胁变量三者间的数量关系。发现:子叶电解质外渗率与酸雨pH值之间具有拟合度很高的Logistic曲线关系。Logistic拟合方程中拐点座标处的酸雨pH值和曲线降低率等参数均与胁程具有一定的相关关系。在pH2.5酸雨胁迫下,电解质外渗率与胁程(24小时之内)之间具有典型的直角双曲线关系。根据这些分析建立了棉花子叶细胞膜透性对酸雨胁迫的应变模型。并提出了一个新的植物逆境生理指标即胁变可逆指数(SI)。

Quantitative correlations amongst the strength, duration of the stress of the simula-ted acid rain, and strain of cell membrane pormeability of the cotyledon disc of cotton.Major results as follows; (1) Correlation for the Logistic curve with high goodnes of fit was found betweenelectrolyte leakage percentage of cotton cotyledon disc and pH values of the simulated acidrain; (2) Some parameters from the fitted Logistic equations had an abundant informationabout plant stress physiology. The relation of rectangular heperbola was found between pHvalue for inflection point coordinate from various fitted Logistic equations and stress dura- tion within 24 hours. The decrease Percentage of Logistic curve increase as stress durationwith positive linear correlation within 10 hours where the inflection point coordinate waslocated; (3) Under stress of the simulated acid rain with pH 2.5, the relation of rectangular,heperbola was found of between electrolyte leakage percentage and stress duration within24 hours; (4) It could been established that multidimensional model includs three variables i.e. strength, duration. and strain under stress of the simulated acid rain based on aboveresults: (?)meaning of footnote: i=atrain variables, EA, EB, ET: j=pH value of acid rain, 5.6 (CK), 5.0, 4.0, …, 1.0, 0.5; k_1=0.5, 0.75, 1.0, 1.5, 2.0, 2.5, 3.0, 3.5, 4.0, 6.0, 8.0, 10.0, 12.0, 24.0hr: k_2=1, 2, 4, …, 10, 12, 24hr. k_3=1, 2, 4, …, 10, 24hr (5) One new index was put forward of the index of strain rever sibility SI ofelectrolyte leakage percentage of cotton cotyledon from the simulated acid rain. It can di-stinguish quatitatively the potential ability of resistance or tolerance to stress of the simula-ted acid rain from various variables of strain, and even from various species of plant.