Gopalakrishnan Subramaniam, Sathya Arumugam, Vijayabharathi Rajendran, Varshney Rajeev Kumar, Gowda C L Laxmipathi, Krishnamurthy Lakshmanan
International Crops Research Institute for the Semi-Arid Tropics (ICRISAT), Patancheru, 502 324, Andhra Pradesh, India.
3 Biotech. 2015 Aug;5(4):355-377. doi: 10.1007/s13205-014-0241-x. Epub 2014 Aug 3.
Modern agriculture faces challenges, such as loss of soil fertility, fluctuating climatic factors and increasing pathogen and pest attacks. Sustainability and environmental safety of agricultural production relies on eco-friendly approaches like biofertilizers, biopesticides and crop residue return. The multiplicity of beneficial effects of microbial inoculants, particularly plant growth promoters (PGP), emphasizes the need for further strengthening the research and their use in modern agriculture. PGP inhabit the rhizosphere for nutrients from plant root exudates. By reaction, they help in (1) increased plant growth through soil nutrient enrichment by nitrogen fixation, phosphate solubilization, siderophore production and phytohormones production (2) increased plant protection by influencing cellulase, protease, lipase and β-1,3 glucanase productions and enhance plant defense by triggering induced systemic resistance through lipopolysaccharides, flagella, homoserine lactones, acetoin and butanediol against pests and pathogens. In addition, the PGP microbes contain useful variation for tolerating abiotic stresses like extremes of temperature, pH, salinity and drought; heavy metal and pesticide pollution. Seeking such tolerant PGP microbes is expected to offer enhanced plant growth and yield even under a combination of stresses. This review summarizes the PGP related research and its benefits, and highlights the benefits of PGP rhizobia belonging to the family Rhizobiaceae, Phyllobacteriaceae and Bradyrhizobiaceae.
现代农业面临着诸多挑战，如土壤肥力丧失、气候因素波动以及病虫害侵袭不断增加。农业生产的可持续性和环境安全性依赖于生物肥料、生物农药和作物残茬还田等生态友好型方法。微生物接种剂，特别是植物生长促进剂（PGP）的多种有益作用，凸显了进一步加强相关研究及其在现代农业中应用的必要性。PGP定殖于根际，从植物根系分泌物中获取养分。作为回报，它们有助于：（1）通过固氮、解磷、产生铁载体和植物激素来富集土壤养分，从而促进植物生长；（2）通过影响纤维素酶、蛋白酶、脂肪酶和β-1,3葡聚糖酶的产生来增强植物保护能力，并通过脂多糖、鞭毛、高丝氨酸内酯、3-羟基丁酮和丁二醇触发诱导系统抗性，增强植物对病虫害的防御能力。此外，PGP微生物具有耐受非生物胁迫的有用变异，如极端温度、pH值、盐度和干旱；重金属和农药污染。寻找这类耐受PGP微生物有望即使在多种胁迫组合下也能促进植物生长并提高产量。本综述总结了与PGP相关的研究及其益处，并强调了属于根瘤菌科、叶杆菌科和慢生根瘤菌科的PGP根瘤菌的益处。
