盐胁迫对3个桑树品种幼苗光合特性的影响

Effects of Salt Stress on Seedling Photosynthetic Characteristics of Three Morus alba Cultivars

研究不同浓度(0、0.2%、0.3%、0.4%)NaC l盐分胁迫处理对3个桑树品种1年生嫁接苗叶片中叶绿素含量和光合作用的影响。结果表明:3个桑树品种的叶绿素a、叶绿素b、总叶绿素含量以及叶绿素a/b均随着盐浓度的增加而降低,叶绿素总量鲁插1号>农桑12号>昌盛。3个品种的净光合速率、蒸腾速率和气孔导度随着盐分浓度的增加而下降,且高盐度降幅明显高于低盐度;而胞间CO2浓度随盐分浓度的增加而升高,增幅最大的是昌盛,最小的是鲁插1号。综合分析发现,3个品种在盐胁迫下的光合能力为:鲁插1号>农桑12号>昌盛。

The effects of salt stress（0,0.2%,0.3% and 0.4% in concentration） on the chlorophyll contents and photosynthesis of one-year-old seedlings of three cultivars of Morus alba（＇Lucha1＇,＇Changsheng＇,＇Nongsang12＇） were studied.The results showed that：The contents of the total chlorophyll,Chl.a,Chl.b and Chl.a/b of the three cultivar seedlings decreased gradually with the increment of salt concentrations,the gradation of the total chlorophyll content was Lucha1Nongsang12Changsheng.The Net photosynthesis rate,transpiration rate and stomatal conductance of the three cultivar seedlings decreased gradually with the increase of salt concentrations,and the decrement of these indices caused by high salt concentration was obviously greater than that of caused by the low salt concentration.The intercellular CO2 concentration of the three cultivar seedlings increased with the increase of salt concentrations,the CO2 concentration increment of ＇Changsheng＇ cultivar seedlings was the maximum,and that of ＇Lucha1＇ cultivar was the minimum.It was indicated through the comprehensive analyses that photosynthetic capacity of the three cultivar seedlings ordered as ＇Lucha1＇ ＇Nongsang12＇ ＇Changsheng＇.