黑暗对西瓜幼苗质量的影响  

Effects of Darkness on the Quality of Watermelon Seedlings

作　　者：段青青[1] 姜武[1] 丁明[1] 黄丹枫[1] 

机构地区：[1]上海交通大学农业与生物学院,上海200240

出　　处：《上海交通大学学报（农业科学版）》2009年第4期374-379,共6页Journal of Shanghai Jiaotong University(Agricultural Science)

基　　金：国家863计划项目(2006AA10A311);上海市"蔬菜学"重点学科建设项目(B209)资助

摘　　要：以西瓜(Citrullus vulgaris Schrad.,cv.Fairfax)为试验材料,模拟贮运光照条件,探讨了常温西瓜幼苗上部鲜重和干重下降。同时,黑暗引起叶绿体变形、淀粉粒消失、基粒减少、基质片层疏松直至消失、膜破损。叶绿体结构的破坏影响幼苗的光化学效率,导致Fo升高、Fv/Fm、Fv/Fo和ФPSⅡ降低。Fv/Fm和Fv/Fo在黑暗2 d以内基本不变,黑暗6 d后分别下降了4.80%和29.76%;黑暗2、4、6 d,ФPSⅡ下降了13.93%、15.69%、29.52%。可见黑暗破坏了叶片的光合机构,造成PSⅡ反应中心活性下降,致使幼苗质量降低。Watermelon （Citrullus vulgaris Schrad., cv. Fairfax） was used to study the effects of darkness on seedling quality in the aspects of morphological indexes, chloroplast ultrastructure and chlorophyll fluorescence parameters. The results demonstrated that after being treated for 2, 4, 6 days in darkness, seedling hypocotyl length increased by 7.22%, 5.68%, 12.31%; seedling leaves fresh weight decreased by 7.75%, 18.36%, 43.92%; and the dry weight decreased by 15.11%, 23.62%, 45.06%; seedling shoot fresh weight and dry weight also decreased by 9.18%, 13.0%, 33.81% and 17.69%, 26.41%, 46.34%. Chloroplast shape became sphericalstarch granules disappeared, granum lamellae decreased, stromal lamellae loosened and disappeared finally with the time. Membrane structure of the chloroplast was also destroyed due to darkness. The photochemistry efficiency reduced because of the damage of chloroplast ultrastructure. Fo was higher than CK and fluctuated greatly through the time of darkness; Fv/Fm and Fv/F0 were almost invariant within 2days of darkness, but declined significantly by 4.80% and 29.76% after being treated for 6 days in darkness; and ФPSⅡ also decreased by 13.93%, 15.69%, 29.52% after dark-treated for 2, 4, 6 days. The chloroplast ultrastructure was injured which induced to decrease of activity of PSⅡreaction center due to darkness. Accordingly thequality of watermelon seedlings was obviously decreased.

关 键 词：黑暗 西瓜 叶绿体结构 叶绿素荧光参数 

分 类 号：S651[农业科学—果树学]