Abstract:
Rhizosphere is the battlefield of beneficial and harmful (so called phytopathogens) microorganisms. Moreover, these microbial communities are struggling for their existence in the soil and playing key roles in plant growth, mineralization, nutrient cycling and ecosystem functioning. In the last few decades, some consistent pattern have been detected so far that link soil community composition and functions with plant growth and development; however, it has not been studied in detail. AM fungi are model organisms, besides potential role in nutrient cycling; they modulate biochemical pathways directly or indirectly which lead to better plant growth under biotic and abiotic stress conditions. In the present investigations, we have elucidated the AM fungi-mediated activation of plant defense responses against Meloidogyne graminicola causing root-knot disease in direct seeded rice (Oryza sativa L.). The study describes the multifarious effects of Funneliformis mosseae, Rhizophagus fasciculatus, and Rhizophagus intraradices inoculated individually or in combination under glasshouse conditions in rice plants. It was found that F. mosseae, R. fasciculatus and R. intraradices when applied individually or in combination modulated the biochemical and molecular mechanisms in the susceptible and resistant inbred lines of rice. AM inoculation significantly increased various plant growth attributes in plants with simultaneous decrease in the root-knot intensity. Among these, the combined application of F. mosseae, R. fasciculatus, and R. intraradices was found to enhance the accumulation and activities of biomolecules and enzymes related to defense priming as well as antioxidation in the susceptible and resistant inbred lines of rice pre-challenged with M. graminicola. The application of F. mosseae, R. fasciculatus and R. intraradices, induced the key genes involved in plant defense and signaling and it has been demonstrated for the first time. Results of the present investigation advocated that the application of F. mosseae, R. fasciculatus and R. intraradices, particularly a combination of all three, not only helped in the control of root-knot nematodes but also increased plant growth as well as enhances the gene expression in rice. Thus, it proved to be an excellent biocontrol as well as plant growth-promoting agent in rice even when the crop is under biotic stress of the root-knot nematode, M. graminicola.
摘要:
根际是有益和有害(所谓的植物病原体)微生物的战场。此外,这些微生物群落在土壤中挣扎着生存,在植物生长中起着关键作用,矿化,养分循环和生态系统功能。在过去的几十年里,到目前为止,已经发现了一些一致的模式,将土壤群落组成和功能与植物生长和发育联系起来;然而,尚未详细研究。AM真菌是模式生物,除了在营养循环中的潜在作用;它们直接或间接地调节生化途径,从而在生物和非生物胁迫条件下导致更好的植物生长。在目前的调查中,我们已经阐明了AM真菌介导的植物防御反应的激活,以抵抗直接播种水稻(OryzasativaL.)中引起根结病的Meloidogynegraminicola。该研究描述了真菌的多种影响,根瘤菌,和在水稻植株的温室条件下单独或组合接种的根瘤菌内。发现F.mosseae,R.fasciculatus和R.intraradices单独或联合应用时,可调节水稻易感和抗性自交系的生化和分子机制。AM接种显着提高了植物的各种植物生长属性,同时降低了根结强度。其中,苔藓的联合应用,R.fasciculatus,和R.intraradices被发现可以增强与防御引发相关的生物分子和酶的积累和活性,以及在接受M.graminicola攻击的水稻的易感和抗性自交系中的抗氧化作用。苔藓的应用,R.fasculatus和R.intraradices,诱导了参与植物防御和信号传导的关键基因,并首次得到证实。目前的调查结果表明,莫沙丝菌的应用,R.fasculatus和R.intraradices,尤其是三者的结合,不仅有助于根结线虫的控制,而且还可以增加植物的生长并增强水稻中的基因表达。因此,即使作物处于根结线虫的生物胁迫下,它也被证明是水稻的优良生物防治剂和植物生长促进剂,M.Graminicola.