缺镁对‘纽荷尔’脐橙不同叶龄叶片叶绿素及荧光特性的影响  

Effects of magnesium deficiency on chlorophyll and fluorescence characteristics of ‘Newhall’ navel orange (Citrus sinensis) leaves at various age

作　　者：凌丽俐[1] 周薇[2] 彭良志[1] 唐玉琴[2] 江才伦[1] 曹立[1] 淳长品[1] 

机构地区：[1]西南大学柑桔研究所,国家柑桔工程技术研究中心,重庆400712 [2]西南大学园林园艺学院,重庆400712

出　　处：《果树学报》2013年第2期235-240,共6页Journal of Fruit Science

基　　金：重庆市科委自然科学基金(cstcjjA80022);国家自然科学基金(31201587);中央高校基本科研业务费专项资金(XD-JK2011C006);现代农业产业技术体系建设专项;重庆市科技攻关计划项目(cstc2012gg-yyjsB80007)

摘　　要：【目的】为了探明缺镁对不同叶龄叶片叶绿素合成与荧光特性的影响,【方法】以2龄枳砧‘纽荷尔’脐橙为试材,定期测定不同叶龄叶片的相对叶绿素含量和荧光参数,研究了缺镁胁迫条件下‘纽荷尔’脐橙不同叶龄叶片的叶绿素合成与荧光特性的动态变化。【结果】(1)随着缺镁时间推移不同叶龄叶片的相对叶绿素含量和Fv/Fm显著降低趋势;且2龄叶相对叶绿素含量和Fv/Fm的降低程度显著大于1龄叶。(2)随着缺镁时间推移不同叶龄叶片的相对电子传递速率(rETR)呈显著降低趋势。缺镁第2个月时仅2龄秋梢叶的rETR显著低于对照,第3个月时1龄春梢叶和夏梢叶的rETR也显著低于对照,至第4个月时所有不同叶龄叶片的rETR均显著低于对照。(3)前3个月不同缺镁叶龄叶片的非光化学淬灭(NPQ)显著高于对照,而第4个月时NPQ均显著低于对照。【结论】随着缺镁时间的延长‘纽荷尔’脐橙不同叶龄叶片的光合能力呈显著降低趋势,缺镁时间过长则导致叶片热耗散能力显著降低。因此,长时间缺镁容易导致‘纽荷尔’脐橙在夏季高光照条件下发生光抑制,产生光伤害。[Objective]This study was to investigate the effects of magnesium deficiency on chlorophyll synthesis and fluorescence characteristics of ＇Newhall＇ navel Grange leaves at various age. [Method] ＇Newhall＇ navel orange （Citrus sinensis Osbeck） young trees grafted on trifoliate orange [Poncirus trifoli- ate（L）] rootstock were grown in sand ： perlite （1：1, v/v） medium and irrigated with nutrient solution con- taining 0 mmol. L-~ （Mg-deficiency） and 1 mmol.L-1 （control） MgSO4, respectively. Relative chlorophyll content and fluorescence characteristic parameters were measured regularly in order to explore the dynam- ic change of chlorophyll synthesis and fluorescence characteristics under magnesium deficient condition. [Result]Under magnesium deficient condition, relative chlorophyll content and maximum quantum effi- ciency （F,/F~） of the leaves at various age remarkably decreased with the experiment. Furthermore, the de- crase was more in 2-year-old leaves than in 1-year-old leaves. Relative electron transport rate （rETR） of magnesium deficient leaves at various age decreased significantly with the experiment. In the 2nd month, rETR of 2-year-old autumn leaves in magnesium deficient group was significantly lower than the control. For 1-year-old spring and summer leaves, rETR in magnesium deficient group also significantly de- creased in the 3rd month. In the 4th month, rETR of all leaves in treatment group was lower Compared with

关 键 词：'纽荷尔’脐橙 缺镁 叶龄 叶绿素 荧光特性 

分 类 号：S666.4[农业科学—果树学]