干旱和盐胁迫对马铃薯试管苗亚细胞结构及生理生化指标的影响  

Effects of Drought and Salt Stress on Subcellular Structure and Physiological and Biochemistry Indicators of Potato Plantlets

作　　者：白江平[1,2] 王晓斌[1,2] 高慧娟[1,2] 胡开明[1,2] 张俊莲[1,3] 王蒂[1,2] 

机构地区：[1]甘肃省作物遗传改良与种质创新重点实验室/甘肃省干旱生境作物学重点实验室,兰州730070 [2]甘肃农业大学农学院,兰州730070 [3]甘肃农业大学园艺学院,兰州730070

出　　处：《西北植物学报》2016年第11期2233-2240,共8页Acta Botanica Boreali-Occidentalia Sinica

基　　金：科技部国际科技合作项目(2014DEG31570);国家自然科学基金(31460369);兰州科技研究项目(2013-4-156);甘肃省财政专项课题(GSCZZX2014-1)

摘　　要：以‘陇薯3号’脱毒试管苗为材料,研究了不同浓度PEG-4000(0、2%、4%、6%、8%)和NaCl(0、25、50、100、200mmol/L)对马铃薯2周大小试管苗根系生长、叶肉细胞超微结构及部分生理生化指标的影响,为筛选耐盐抗旱马铃薯种质提供理论依据。结果显示:(1)随着PEG-4000和NaCl浓度的增加,马铃薯试管苗根总长、根体积、根数均呈现下降趋势,并且胁迫浓度越高时间越长其下降趋势越明显,而盐胁迫处理的下降幅度明显大于PEG胁迫处理。(2)随着PEG-4000和NaCl浓度的增加,马铃薯试管苗叶肉细胞细胞壁明显变厚,发生明显的质壁分离,嗜锇颗粒显著增加,出现大量囊泡,叶绿体损害逐渐加剧,直至完全解体。(3)随着PEG-4000和NaCl浓度的增加,马铃薯试管苗脯氨酸(Pro)含量显著增加,过氧化氢(CAT)和超氧化物歧化酶(SOD)活性显著增强,而其丙二醛(MDA)含量迅速增加,但叶片叶绿素含量持续下降。研究表明,在PEG-4000模拟干旱和NaCl胁迫条件下,马铃薯试管苗叶片叶绿体结构受到严重损害,叶绿素含量显著降低,且胁迫程度越强损害越严重、下降幅度越大;同时,干旱和高盐胁迫也诱导马铃薯试管苗脯氨酸含量和抗氧化酶CAT和SOD活性显著上调,一定程度上缓解了干旱和高盐胁迫的伤害。In this study, the detoxification potato plantlets plants of ‘Longshu No.3’ were cultivated under PEG 4000（0, 2%, 4%, 6% and 8% PEG） and gradient saline stress （0, 25, 50, 100 and 200 mmol·L NaCl） respectively. The root growth and the ultrastructure of mesophyll cell were observed two weeks later. The physiological and biochemical indices were measured to provided the theoretical basis for screening salt tolerant and drought resistant potato germplasm. The results showed that： with the increase of external PEG 4000 or NaCl concentration, （1） the total of root length, root volume and root number were decreased. With extension of time the decrease was obvious. This decline in salt stress obviously greater than that in drought stress, explained that roots were sensitive to salt stress; （2） potato plantlet cell wall obviously thickened and plasmolysis, plastoglobuli markedly increased, numerous vesicles, chloroplasts gradually damaged to a complete disorganization; （3） potato plantlet plants leaf proline content significantly increased, the activities of catalase （CAT） and superoxide dismutase （SOD） and malondialdehyde （MDA） content significantly increased, while chlorophyll content decreased. In conclusion, the PEG 4000 simulated drought and salt stress could cause serious damage of plant chloroplast structure and chlorophyll content significantly decreased. The more stress and the more serious damage. Simultaneously, drought and salt stress also induced that potato plantlet leaf proline content and the activities of catalase （CAT） and superoxide dismutase （SOD） significantly increased and alleviated the drought and high salt stress injury.

关 键 词：马铃薯 干旱胁迫 NACL胁迫 叶片亚细胞结构 生理指标 

分 类 号：Q945.78[生物学—植物学]