【作者】 杨明；

【导师】 魏珉； 高中强；

【作者基本信息】 山东农业大学 ， 农艺与种业（专业学位）， 2024， 硕士

【摘要】 黄瓜是我国设施栽培的主要蔬菜之一,低温弱光是冬季黄瓜设施栽培的主要障碍因素。上世纪90年代以来,伴随设施栽培发展,黄瓜主栽品种不断更换,但对不同年代主栽品种的性状演变特征缺乏系统研究。本论文选用上世纪80年代‘新泰密刺’、90年代‘津优1号’、本世纪初‘津绿3号’、2010年前后‘德瑞特2号’和近年‘德瑞特7号’,共5个代表不同年代的日光温室黄瓜主栽品种,通过低温（昼12℃/夜8℃）、弱光(100μmol·m^-2·s^-1)处理,研究其生长和生理响应特征,以期为黄瓜耐低温弱光栽培和新品种选育提供指导。主要结果如下:1.低温胁迫抑制黄瓜幼苗的生长,株高、茎粗和干物质增量减少,根系活力和叶绿素含量降低。不同品种按冷害指数高低排序为‘新泰密刺’、‘津绿3号’、‘津优1号’、‘德瑞特2号’、‘德瑞特7号’。2.随着低温胁迫时间延长,黄瓜幼苗叶片净光合速率降低,电解质渗漏率、渗透调节物质和MDA含量增加,SOD、CAT活性先升高后降低,POD活性持续升高。与其它品种相比,‘德瑞特7号’渗透调节物质含量最高,MDA积累量最少。3.通过主成分分析和隶属函数法综合评价,黄瓜品种耐冷性高低顺序为‘德瑞特7号’、‘德瑞特2号’、‘津优1号’、‘津绿3号’、‘新泰密刺’。冷害指数、叶片电解质渗漏率、Pn和MDA含量可作为评价黄瓜耐冷能力的指标。4.弱光胁迫下黄瓜幼苗的生长受抑,叶面积和干物质增量减少,根系活力下降,叶绿素a和叶绿素b含量升高。与其它品种相比,‘德瑞特7号’生长受抑制最小。5.随着弱光胁迫时间延长,黄瓜幼苗叶片净光合速率下降,MDA含量增加,SOD活性下降,CAT和POD活性上升。弱光下‘德瑞特2号’和‘德瑞特7号’维持较高的光合速率以及POD和CAT活性。6.通过主成分分析和隶属函数法综合评价,黄瓜品种耐弱光能力由高到低顺序为‘德瑞特2号’、‘德瑞特7号’、‘津绿3号’、‘津优1号’、‘新泰密刺’。Pn、POD活性、CAT活性可作为评价黄瓜耐弱光能力的指标。更多还原

【Abstract】 Cucumber is one of the main vegetables in facility cultivation in China.Low temperature and weak light are the main obstacles to facility cultivation of cucumber in winter.Since the1990s,with the development of facility cultivation,the main varieties of cucumber have been changed constantly,but there is a lack of systematic research on the character evolution characteristics of the main varieties in different years.In this paper,five main cucumber varieties representing different eras in solar greenhouse were selected from the’Xintaimici’thorn’of the early 1980s,1990s,’Jinyou 1’,early this century,’Jinlv 3’,around 2010,’Deruite2’and recent years,’Deruite 7’.The growth and physiological response characteristics of cucumber were studied by low temperature（12℃day/8℃night）and weak light(100μmol·m^-2·s^-1),in order to provide guidance for low temperature and weak light resistance cultivation and breeding of new varieties.The main results are as follows:1.Low temperature stress inhibited the growth of cucumber seedlings,decressed plant height,stem diameter and dry matter increment,and decreased root activity and chlorophyll content.According to the cold damage index,the different varieties were ranked as’Xintaimici’,’Jinlv 3’,’Jinyou 1’,’Deruite 2’and’Deruite 7’2.With the prolonged low temperature stress,the net photosynthetic rate of cucumber seedlings decreased,the content of electrolyte leakage,osmotic regulatory substances and MDA increased,the activities of SOD and CAT increased first and then decreased,and the activity of POD increased continuously.Compared with other varieties,’Deruite 7’had the highest content of osmoregulatory substances and the lowest amount of MDA accumulation.3.According to the comprehensive evaluation by principal component analysis and membership function method,the cold tolerance of cucumber varieties was in the order of’Deruite 7’,’Deruite 2’,’Jinyou 1’,’Jinlv 3’and’Xintaimici’.Chilling damage index,leaf electrolyte leakage rate,Pn and MDA contents can be used as indexes to evaluate the cold tolerance of cucumber.4.Under weak light stress,the growth of cucumber seedlings was inhibited,leaf area and dry matter increment decreased,root activity decreased,chlorophyll a and chlorophyll b contents increased.Compared with other varieties,the growth of’Deruite 7’was least inhibited.5.With the extension of weak light stress time,the net photosynthetic rate of cucumber seedlings decreased,MDA content increased,SOD activity decreased,and CAT and POD activities increased.’Deruite 2’and’Deruite 7’maintained high photosynthetic rates and POD and CAT activities under weak light.6 According to the comprehensive evaluation by principal component analysis and membership function method,the weak light resistance of cucumber varieties from high to low was’Deruite 2’,’Deruite 7’,’Jinlv 3’,’Jinyou 1’and’Xintaimici’.Pn,POD and CAT activities can be used to evaluate the weak light resistance of cucumber.更多还原