摘要
为探究腐殖酸(Humic acid,HA)对于提高甜瓜植株抗冷性的作用。本试验以厚皮甜瓜品种‘玉菇’为试材,以清水处理为对照(CK),研究了HA灌根处理(300 mg/L)对低温胁迫下(10℃/5℃)甜瓜幼苗生长形态、光合特性、叶绿素荧光参数及抗坏血酸-谷胱甘肽循环(AsA-GSH)的影响。结果表明,低温胁迫明显抑制了植株生长。与CK相比,HA处理的甜瓜幼苗株高、茎粗、地上部和地下部鲜重显著增加。同时提高了叶绿素相对含量(SPAD)、净光合速率(Pn)、气孔导度(Gs)和蒸腾速率(Tr)、最大光化学效率(Fv/Fm)、潜在光化学效率(Fv/Fo)和非调节性能量耗散系数(NPQ),显著降低了胞间CO_(2)浓度(Ci)和初始荧光(Fo)。此外,HA通过提高还原型抗坏血酸(AsA)和谷胱甘肽(GSH)含量,增强抗坏血酸过氧化物酶(APX),谷胱甘肽还原酶(GR),脱氢抗坏血酸还原酶(DHAR)和单脱氢抗坏血酸还原酶(MDHAR)活性,上调相关基因CmAPX、CmGR、CmMDHAR和CmDHAR的表达水平,加速了AsA-GSH循环,显著降低了幼苗叶片的超氧阴离子产生速率(O_(2)^(-)·)和丙二醛含量(MDA)。综上所述,低温胁迫下HA通过提高幼苗生物量,优化叶片光合参数和叶绿素荧光参数,促进AsA-GSH循环中抗氧化物质的合成和关键酶活性,并且上调相关基因的表达水平,提高甜瓜幼苗抗冷性。
Low-temperature stress is a critical factor restricting winter and early spring melon production in China.There are few reports on the effects of Humic acid(HA)on cold tolerance of melon plants.In this experiment,a thick-skinned melon variety‘Yugu’was used as the material with water treatment as the control(CK).The study investigated the effects of HA treatment(300 mg/L)on the growth morphology,photosynthetic characteristics,chlorophyll fluorescence parameters,and the Aascorbic Acid-Glutathione(AsA-GSH)cycle,including the impact on antioxidant substances,key enzyme activities,and gene expression levels,under low-temperature stress conditions(10℃/5℃).With the prolonged duration of low-temperature stress,the growth of plants was significantly inhibited.Compared to the control plants,melon seedlings treated with HA exhibited a significant increase in plant height,stem thickness,aboveground and underground fresh weight.Additionally,HA increased the relative content of chlorophyll(SPAD),net photosynthetic rate(Pn),stomatal conductance(Gs),transpiration rate(Tr),maximum photochemical efficiency(Fv/Fm),potential photochemical efficiency(Fv/Fo),and non-photochemical quenching coefficient(NPQ).Furthermore,it significantly reduced intercellular CO_(2)concentration(Ci)and initial fluorescence(Fo).It accelerated the AsA-GSH cycle,significantly reduced the superoxide anion generation rate(O_(2)^(-)·),and malondialdehyde content(MDA)in seedling leaves by increasing the content of reduced ascorbic acid(AsA)and glutathione(GSH),enhancing the activities of ascorbate peroxidase(APX),glutathione reductase(GR),dehydroascorbate reductase(DHAR),and monodehydroascorbate reductase(MDHAR),and upregulating the expression levels of related genes CmAPX,CmGR,CmMDHAR,and CmDHAR,Overall,HA treatment significantly increased the biomass of seedlings under low-temperature stress,effectively improved leaf photosynthetic parameters and chlorophyll fluorescence parameters,and maintained photosystem activity.By optimizing the synthesis of antioxidant substances and key enzyme activities in the AsA-GSH cycle,and upregulating the expression levels of related genes,HA significantly alleviated membrane peroxidation damage in leaves,thereby enhancing the cold resistance of melon seedlings.
作者
朱立保
刘海河
张彦萍
曹艳霞
王艳
王玉红
康凯伦
祁泽阳
ZHU Libao;LIU Haihe;ZHANG Yanping;CAO Yanxia;WANG Yan;WANG Yuhong;KANG Kaiun;QI Zeyang(College of Horticulture,Hebei Agricultural University,Baoding,Hebei 071001,China;Xianxian City Agricultural and Rural Bureau,Cangzhou 062250,China.)
出处
《河北农业大学学报》
CAS
CSCD
北大核心
2024年第5期75-83,92,共10页
Journal of Hebei Agricultural University
基金
国家西甜瓜产业技术体系资助项目(CARS-26-25)
河北省现代种业科技创新专项资助项目(21326306D)
河北省农业科技成果转化资金专项资助项目(冀科农函〔2022〕45号)
河北省农业科技成果转化资金专项资助项目(冀科农〔2023〕9号)
河北省蔬菜产业体系岗位专家资助项目(HBCT2018030202).
