【作者】 卢艳；

【导师】 王飞；

【作者基本信息】 西北农林科技大学 ， 园艺植物种质资源学， 2011， 硕士

【摘要】 盐胁迫是抑制果树生长、降低果树产量的主要环境因素之一,而嫁接是苹果(Malus)的主要繁育方式,前人对其耐盐性大多集中在砧木上,而不同砧穗组合的耐盐性强弱鲜有报道。研究不同苹果砧穗组合的耐盐性差异,对筛选耐盐性强的苹果砧穗组合以及阐明盐胁迫下不同苹果砧穗组合的耐盐机理具有重要意义。该试验以盆栽3年生4种不同砧穗组合的苹果苗为试材,研究了不同浓度的NaCl(0.2%、0.4%、0.6%)胁迫下不同砧穗组合的苹果苗的耐盐反应,研究结果如下:1、4种不同砧穗组合的枝条生长率、叶面积生长量、叶绿素(chl)含量与胁迫浓度和胁迫天数呈负相关;电导率和丙二醛(MDA)含量随着胁迫浓度的增加和时间的延长而升高,其中MDA含量在胁迫后期又有所降低;可溶性蛋白含量和SOD活性随着胁迫浓度的增加和时间的延长呈现先升高再降低的趋势,叶绿素b对盐胁迫的敏感性较强。2、盐胁迫14d后各组合的光合特性研究发现,不同砧穗组合的净光合速率( Pn)、气孔导度(Gs)和蒸腾速率(Tr)随NaCl胁迫浓度的增加而降低,这与生长指标和叶绿素含量变化一致。0.2%NaCl胁迫时气孔限制因素起主导作用,而在0.4%、0.6%NaCl胁迫时,气孔限制因素和非气孔限制因素共同起作用。3、对各种生长、生理指标进行综合主成分回归分析,结果表明:枝条生长率,叶面生长量和叶绿素b含量这3个指标与耐盐性的相关性最强,可溶性蛋白含量和SOD活性相关性较弱。同砧不同接穗的耐盐性为M26/长富2号> M26/富红早嘎、八棱海棠/嘎啦>八棱海棠/陕富3号。4种砧穗组合的耐盐性强弱依次为:M26/长富2号>八棱海棠/嘎啦> M26/富红早嘎>八棱海棠/陕富3号。更多还原

【Abstract】 Salt stress was one of the major environmental factors that inhibited fruit growth and reduced fruit yield,and the grafting as main apple breeding method had an important influence on apple salt tolerance.Studying the growth and physiological variation of different rootstock-scion combinations stressed by NaCl was great significance in elucidating the mechanism of salt damage and screening of strang salt tolerance of apple rootstock-scion combinations.Four groups of three years old apple tree cultivated in the pot with different rootstock-scion combinations were stressed by NaCl with different concentration (0,0.2%,0.4% and 0.6% NaCl) in the treated soil and shoot growth rate,leaf area growth,cell membrane permeability,Chlorophyl,MDA,soluble protein, SOD and the photosynthetic capacity were investigated. The results showed that shoot growth rate,leaf area growth, chlorophyll content reduced when the stress concentration of NaCl and stress time increased, and were negatively correlated with the stress concentration and time;cell membrane permeability and MDA content increased with the stress concentration and time increased, but MDA content reduced in the end of stress;soluble protein content and SOD activity increased firstly and then decrease with the stress concentration and time increased.The effect of NaCl stress after 14 days to the photosynthetic capacity were investigated and the result showed that net photosynthetic rate (Pn),stomatal conductance (Gs),transp iration rate (Tr),the content of chlorophyll b(chlb)and leaf growth reduced,but cell membrane permeability increased when increasing salt stress.The photosynthesis decline in the low-salinity stress was principally influenced by stomatal limitation,and in the middle and high salinity stress, stomatal limitation and non-stomatal limitation plays a role commonly.Different rootstock-scion combinations shewd different sensitivity to NaCl stress,also different indicators of growth and physiological were different. Comprehensive principal component analyse of 8 indicators showed that shoot growth rate, leaf growth and chlorophyll b content was in the stronger correlation between salt tolerance than soluble protein and SOD activity,and the strength of salt tolerance of rootstock-scion combination were M26/ChangFu2,Malus/Gala, M26/FuHungZaoGa, Malus/ShanFu3 in descending.更多还原