Departamento de Microbiología del Suelo y Sistemas Simbióticos. Estación Experimental del Zaidín (CSIC). Profesor Albareda n° 1, 18008 Granada, Spain.
Plant Sci. 2013 Mar;201-202:42-51. doi: 10.1016/j.plantsci.2012.11.009. Epub 2012 Dec 3.
High soil salinity is a serious problem for crop production because most of the cultivated plants are salt sensitive, which is also the case for the globally important crop plant maize. Salinity stress leads to secondary oxidative stress in plants and a correlation between antioxidant capacity and salt tolerance has been demonstrated in several plant species. The plant antioxidant capacity may be enhanced by arbuscular mycorrhizal fungi (AMF) and it has been proposed that AM symbiosis is more effective with native than with collection AMF species. Thus, we investigated whether native AMF isolated from a dry and saline environment can help maize plants to overcome salt stress better than AMF from a culture collection and whether protection against oxidative stress is involved in such an effect. Maize plants inoculated with three native AMF showed higher efficiency of photosystem II and stomatal conductance, which surely decreased photorespiration and ROS production. Indeed, the accumulation of hydrogen peroxide, the oxidative damage to lipids and the membrane electrolyte leakage in these AM plants were significantly lower than in non-mycorrhizal plants or in plants inoculated with the collection AMF. The activation of antioxidant enzymes such as superoxide dismutase or catalase also accounted for these effects.
土壤高盐度是作物生产的一个严重问题,因为大多数栽培植物对盐敏感,全球重要的作物玉米也是如此。盐胁迫会导致植物的次生氧化应激,并且在几种植物中已经证明了抗氧化能力与耐盐性之间存在相关性。丛枝菌根真菌(AMF)可以增强植物的抗氧化能力,并且已经提出,与收集的 AMF 物种相比,AM 共生在本地 AMF 中更为有效。因此,我们研究了从干旱和盐渍环境中分离出来的本地 AMF 是否比从培养物中分离出来的 AMF 更能帮助玉米植株克服盐胁迫,以及这种效应是否涉及对氧化应激的保护。与非菌根植物或接种收集的 AMF 的植物相比,接种了三种本地 AMF 的玉米植物表现出更高的光合作用 II 系统效率和气孔导度,这肯定降低了光呼吸和 ROS 的产生。事实上,这些 AM 植物中过氧化氢的积累、脂质的氧化损伤和膜电解质泄漏的程度明显低于非菌根植物或接种收集的 AMF 的植物。超氧化物歧化酶或过氧化氢酶等抗氧化酶的激活也解释了这些效应。