NaCl胁迫对番茄嫁接苗光合作用和叶绿素荧光特性的影响

Effects of NaCl Stress on Photosynthetic and Fluorescence Parameters in Grafted Tomato Seedlings

采用水培的方法,以野生番茄为砧木,栽培番茄为接穗进行嫁接,从番茄叶片的光合特性和叶绿素荧光特性两方面研究嫁接对100mmol.L-1 NaCl胁迫下番茄幼苗的影响。结果表明,NaCl胁迫下,番茄自根苗的净光合速率和蒸腾速率下降,嫁接苗受影响较小。盐胁迫下,自根苗的ΦPSⅡ和Fv/Fm下降,NPQ显著上升,而嫁接苗受盐害影响不明显。因此说明,盐害引起的渗透胁迫主要因为非气孔限制,嫁接提高番茄的光合速率和水分利用效率,有利于番茄对光能的捕获和转化,减少电子传递过程中以热能耗散的光能,降低盐胁迫对番茄生长的抑制作用,促进番茄植株生长。

Tomato（Lycopersicon esculentum Mill.） is an important vegetable and widely cultured in open field and greenhouse.The secondary salinization in the soil is becoming heavier and has become one of main factors limiting the sustainable development of vegetable production,and grafting is an important agricultural technique to enhance salt stress tolerance of tomato.Herein using wild tomato as the rootstock,the effects of grafting on the photosynthetic and fluorescence parameters of tomato seedling leaves were investigated under the hydroponic condition of 100 mmol·L^-1 NaCl.The results shows that,under the condition of salt stress,net photosynthetic rate,transpiration rate,ΦPSⅡ and Fv/Fm of self-rooted tomato seedlings decreased,and NPQ increased significantly,however,less effects were detected in grafted seedling.Thus,grafting could improve the capture and conversion of light energy and improve the osmotic adjustment ability of tomato seedlings subjected salt stress and improve plant growth.