盐碱胁迫对两个葡萄品种光合作用-光响应特性的影响

在3种不同盐碱胁迫:低度、中度、重度盐碱胁迫条件下,分析了葡萄品种“克瑞森”和“青提”2 a生叶片的光合作用-光响应特性、叶绿素含量及长势情况.结果表明:“克瑞森”、“青提”光合作用-光响应曲线符合非直角双曲线模型.盐碱胁迫没有降低2个葡萄品种的光合能力,而是增强其光合能力,表观量子效率AQY值的上升表明盐碱胁迫下2个葡萄品种对光的响应敏感性较强,对弱光的利用能力较高.净光合速率(Pn)、暗呼吸速率(Rd)、叶绿素含量及长势情况说明“青提”较“克瑞森”具有更强的盐碱适应性能力.同时,2种葡萄在受到盐碱胁迫后其净光合速率的降低不是由于气孔的关闭引起CO2供应不足造成的,而是受强光下光抑制的加强等非气孔限制因素的影响,包括叶肉阻力增大、羧化酶活性和RuBP再生速率降低等.

The Photosynthesis-light Response Characteristics Influence of Two Grape Varieties under the Stress of Soil Salinity-alkalinity

Under three different salinity-alkalinity stress:low-grade salinity-alkalinity stress,moderate salinity-alkalinity stress and severe salinity-alkalinity stress condition,analyzed the photosynthesis-light response characteristics,chlorophyll content and growing conditionsof leaves of ‘Krison’ and ‘Grape white’.The results showed that the photosynthesis-light response curve of ‘Krison’ and ‘Grape white’ met the non orthogonal hyperbolic model.Salinity-alkalinity stress not reduced the photosynthetic potential of two grape varieties,but enhanced its photosynthetic capacity.The increase of AQY(Aapparent Quantum Yield)showed that two grape varieties under the salinity-alkalinity stress were sensitive to the light,the use capacity of weak light was high.Net Photosynthetic Rate(Pn),Dark Respiratory Rate(Rd),chlorophyll content and growing condition were contribute to explain ‘Grape white’ had stronger salinity-alkalinity adaptive capacity.Meanwhile,the decrease of Pn of two kinds of grapes under salinity-alkalinity stress were not because of the closure of the stomata,caused by inadequate supply of CO2,but by the strength of strong light photo inhibition result in the non stomatal limitation factors,including mesophyll resistance increases,carboxylase enzyme activity and RuBP regeneration rate,etc.