水分胁迫对‘赤霞珠’葡萄不同叶龄叶片糖含量及相关代谢酶活性的影响

Effects of Water Stress on Sugar Content and Related Metabolic Enzyme Activities in Leaves of‘Cabernet Sauvignon’Grape at Different Leaf Ages

以三年生‘赤霞珠’葡萄为试材,通过控制灌溉量,以黎明前叶片水势(Ψb)反映胁迫程度,设置无水分胁迫、中度水分胁迫和重度水分胁迫3个处理,研究了‘赤霞珠’葡萄新梢基部(叶1)、下部(叶2)、中部(叶3)、中上部(叶4)、上部(叶5)叶片的糖含量及其相关代谢酶活性,以期明确水分胁迫对‘赤霞珠’葡萄不同叶龄叶片糖含量及其相关代谢酶活性的影响。结果表明:中度水分胁迫处理下,葡萄新梢不同叶龄叶片蔗糖、可溶性糖含量均高于对照组,处理前期还原糖含量低于对照组;处理中后期还原糖含量高于对照组;重度水分胁迫处理下,葡萄新梢不同叶龄叶片蔗糖含量低于对照组、还原糖含量高于对照组;在处理前期,叶35可溶性糖含量高于对照组,后期各叶龄叶片可溶性糖含量逐渐低于对照组;中度水分胁迫可以提高叶35叶片蔗糖磷酸合成酶(SPS)活性,而重度水分胁迫降低了不同叶龄叶片蔗糖磷酸合成酶(SPS);水分胁迫可以提高叶35叶片中性转化酶(NI)活性、不同叶龄叶片蔗糖合成酶(SS)和酸性转化酶(AI)活性;中度水分胁迫有利于不同叶龄叶片糖分的积累及相关代谢酶活性的提高。

Three-year-old ‘Cabernet Sauvignon’ grape was used as experiment material,three treatments of without water stress,moderate water stress and heavy water stress were adopted by controlling the amount of irrigation and the degree of stress was reflected by leaf water potential(Ψb) before dawn,the sugar content and related metabolic enzyme activities in the base(leaf 1),the underneath(leaf 2),the middle(leaf 3),the middle-upper(leaf 4) and the upper(leaf 5) leaves of ‘Cabernet Sauvignon’ young sprout were analyzed,in order to study the effect of water stress on sugar content and related metabolic enzyme activities in leaves of ‘Cabernet Sauvignon’ at different leaf ages.The results showed that under moderate water stress,the sucrose and soluble sugar content of different age leaves were higher than those of the control,and the reducing sugar content in the early stage was lower;the reducing sugar content in the middle and late stages was higher than control.Under severe water stress,the sucrose content of grape leaves at different ages was lower than control,and the reducing sugar content was higher than control.In the early stage of treatment,the soluble sugar content of leaves 3-5 was higher than control,and the soluble sugar content of leaves at different ages in the later stage was gradually lower than control.Moderate water stress could increase the sucrose phosphate synthase(SPS) activity of leaves 3-5,while severe water stress reduced the sucrose phosphate synthase(SPS) of leaves with different ages;water stress could increase the neutral transformation of leaves 3-5 enzyme(NI) activity,sucrose synthase(SS) and acid invertase(AI) activities of leaves at different ages.Moderate water stress was beneficial to the accumulation of sugarand the improvement of related metabolic enzyme activities in different age leaves.