盐胁迫对小粒大豆幼苗生长发育及光合特性的影响

Effects of Salt Stress on Seedling Growth and Photosynthetic Characteristics of Glycine gracilis

本文研究了不同盐(NaCl∶Na_2SO_4=1∶1和NaHCO_3∶Na_2CO_3=1∶1)胁迫对小粒大豆东农690植株生长发育及光合特性的影响。结果表明:低浓度的中性盐对小粒豆生长具有一定的促进作用,低浓度的碱性盐对小粒豆生长抑制作用不明显;较高浓度盐胁迫抑制小粒豆生长。在两种盐浓度高于60 mmol·L^(-1)胁迫条件下,植株的生长发育及光合特性大幅改变,与对照相比差异极显著。小粒豆株高、根长、根瘤菌数、单株叶面积、干鲜比、净光合速率(Pn)、气孔导度(Gs)、蒸腾速率(Tr)、气孔限制值(Ls)各值与两种盐胁迫均呈极显著负相关;叶绿素含量与中性盐胁迫呈显著负相关,与碱性盐胁迫呈极显著负相关;叶片外浸液相对电导率、胞间CO_2浓度(Ci)与两种盐胁迫均呈极显著正相关。

This study examined the effects of various salt stresses（NaCl∶Na2SO4=1∶1 和 NaHCO3∶Na2CO3=1∶1） on the plant growth and photosynthetic characteristics of small soybean variety Dongnong 690.The result showed that the low concentration of neutral salt accelerated the growth of Glycine gracilis to a certain extent,while alkaline salt didn＇t induce obvious resistance,the high concentration of salt stress restrained the growth of Glycine gracilis.Under the condition of two kinds salt concentration higher than 60 mmol·L^-1 stress,compared with the control,the growth and photosynthetic characteristic of plant changed significantly.Each value of root length,root nodule bacteria number,leaf area,fresh and dry ratio,net photosynthetic rate（Pn）,stomatal conductance（Gs）,transpiration rate（Tr）,and stomatal limitation value（Ls） of small soybean were significantly negatively correlated with two kinds of salt stress.Chlorophyll content was negatively correlated with neutral salt stress and negatively correlated with alkaline salt stress.Leaf extracts relative conductivity and intercellular CO2 concentration（Ci） were significantly and positively correlated with two kinds of salt stress.