摘要
为探明哈密瓜对低温胁迫生理及光合变化规律.本研究以前期选出的耐低温品种'比斜克齐'为试材,通过4 ℃低温处理,测定哈密瓜幼苗第二片真叶的叶绿素、可溶性糖、可溶性蛋白、游离脯氨酸的含量、SOD、POD酶活性变化、光合速率与叶绿素荧光.结果表明,电导率、可溶性糖、可溶性蛋白、游离脯氨酸含量随着低温处理时间的增加而升高;SOD酶活性先下降后上升,POD活性一直升高.低温胁迫总叶绿素、叶绿素a和叶绿素b含量均呈先增后减再增的趋势;Pn呈下降趋势;Gs呈先下降后上升的趋势;胞间CO2浓度上升,气孔限制值下降,Fm、Fv/Fm、Fv/Fo明显下降,Fo、Fv先上升再下降.此外,随着低温处理时间的增加,哈密瓜抗寒品种的抗氧化能力和渗透调节能力也随之增强,光合作用减弱,胞间CO2浓度上升,叶绿素荧光下降.本研究结果为哈密瓜抗寒品种的选育提供理论依据.
Abstract
The experiment was conducted to study the effect of low temperature on the physiological and photosynthetic changes of Hami melon.In this study,the low-temperature tolerant variety'Bishkezi'was selected as the test material.The contents of chlorophyll,soluble sugar,soluble protein,free proline,the activities of SOD and POD enzymes,photosynthetic rate and chlorophyll fluorescence of the second true leaves of Hami melon seedlings were determined under 4 ℃ low temperature.The results showed that the electrical conductivity,soluble sugar,soluble protein,and free proline content increased with the increase of low temperature treatment time;the activities of SOD enzyme was first decreased and then increased,and POD activity increased gradually.The contents of Chl,Chla and Chlb increased initially,then decreased and followed by an increase.Gs was first decreased and then increased;intercellular CO2 concentration increased,stomatal limitation value decreased,Fm,Fv/Fm,Fv/Fo decreased significantly,Fo and Fv increased and then decreased.In addition,with the increase of low temperature treatment time,the antioxidant capacity and osmoregulation capacity Hami melon cold-resistant va-rieties were enhanced,photosynthesis was weakened,intercellular CO2 concentration increased,and chlorophyll fluorescence decreased.The results of this study provide a theoretical basis for the selection and breeding of cold-resistant varieties of Hami melon.
基金项目
塔里木大学研究生科研创新项目(TDGRI202025)
塔里木大学校长基金项目(TDZKKY202101)
塔里木大学校长基金项目(TDZKBS-202106)
NETL
NSTL
万方数据