中文摘要：在全球范围内，花生是一种可在不同农业气候区种植的重要油料作物。土壤盐分是花生种植的主要制约因素之一。本文为了了解盐分胁迫的生物化学机制，在有防护措施的盆栽中，对拥有甘露醇脱氢酶基因（mtlD）的四种转基因花生品系进行不同程度盐分胁迫。研究发现，相对于野生型花生品系来说，所有转基因花生品系的甘露醇脱氢酶基因活性和甘露醇积累量都较高；在盐分胁迫下，相对于野生型花生品系来说，所有转基因花生品系的超氧化物歧化酶、过氧化氢酶、过氧化物酶、抗坏血酸过氧化物酶、谷胱甘肽还原酶活性显著升高，而H2O2和丙二醛含量显著降低，且抗坏血酸和相对含水量都较高；MTLD活性与各种抗氧化酶、生长参数和相对含水量呈显著正相关，而与H2O2、丙二醛呈显著负相关；MTLD转基因花生株在盆栽条件下均保持较低的氧化损伤，这表明通过甘露醇积累和抗氧化反应增强保护机制可改良盐分诱导的氧化应激。此外，这些品种可作为耐盐品种，在开放的田间试验进行测试。
外文摘要：Globally, peanut is an important oilseed crop, which is cultivated under different agro-climatic zones. Soil salinity is one of the major constraints in peanut cultivation. Therefore, to understand the physio-biochemical mechanisms imparting salinity stress, four transgenic peanut lines (cv. GG20) already developed and confirmed by our lab, having bacterial mannitol dehydrogenase gene (mtlD), were subjected to different levels of salinity stresses (1, 2 and 3 dS m(-1)) in pots under containment facility. Further, these lines were also characterized for various physio-biochemical parameters at flowering, pegging and pod formation stages. All the transgenic lines recorded significantly higher mannitol dehydrogenase (MTD) activity and mannitol accumulation than the wild type (WT). Under salinity stress, significantly higher levels of superoxide dismutase, catalase, guaiacol peroxidase, ascorbate peroxidase, glutathione reductase activities, while significantly lower levels of H2O2 and malondialdehyde contents, were recorded in the transgenics compared to WT. Similarly, significantly higher ascorbic acid and relative water content (RWC) were recorded in transgenic lines. The MTD activity showed positive correlation with various antioxidant enzymes, growth parameters and RWC, while negative correlation was recorded with H2O2 and malondialdehyde content at most of the plant growth stages. The mtlD transgenic peanut lines under pot conditions were found maintaining lower oxidative injuries, indicating amelioration of salinity-induced oxidative stress by enhanced protection mechanisms via mannitol accumulation and antioxidative responses. The best lines identified (MTD1 and MTD4) may be used further as pre-breeding source for imparting salinity stress tolerance in peanut. Besides, these lines may also be tested under open-field trials for release as salt-tolerant variety.
外文关键词：Antioxidant enzymes；Groundnut；Mannitol dehydrogenase；Oxidative injury；Soil salinity
作者：Patel, Kirankumar G；Mandaliya, Viralkumar B； Mishra, Gyan P；等
作者单位：ICAR Directorate Groundnut Res
期刊名称：ACTA PHYSIOLOGIAE PLANTARUM
期刊影响因子：1.563
出版年份：2016
出版刊次：6
点击下载：高表达mtlD基因的转基因花生，可通过甘露醇积累和不同的抗氧化反应来增强耐盐性