Department of Soil Science and Agricultural Chemistry, Institute of Agricultural Sciences, Banaras Hindu University, Varanasi 221005, India.
Institute of Environment and Sustainable Development, Banaras Hindu University, Varanasi 221005, India.
Microbiol Res. 2014 May-Jun;169(5-6):337-47. doi: 10.1016/j.micres.2013.09.003. Epub 2013 Dec 4.
The potassium solubilizing microorganisms (KSMs) are a rhizospheric microorganism which solubilizes the insoluble potassium (K) to soluble forms of K for plant growth and yield. K-solubilization is carried out by a large number of saprophytic bacteria (Bacillus mucilaginosus, Bacillus edaphicus, Bacillus circulans, Acidothiobacillus ferrooxidans, Paenibacillus spp.) and fungal strains (Aspergillus spp. and Aspergillus terreus). Major amounts of K containing minerals (muscovite, orthoclase, biotite, feldspar, illite, mica) are present in the soil as a fixed form which is not directly taken up by the plant. Nowadays most of the farmers use injudicious application of chemical fertilizers for achieving maximum productivity. However, the KSMs are most important microorganisms for solubilizing of fixed form of K in soil system. The KSMs are an indigenous rhizospheric microorganism which shows effective interaction between soil and plant systems. The main mechanism of KSMs is acidolysis, chelation, exchange reactions, complexolysis and production of organic acid. According to literature, currently negligible use of potassium fertilizer as a chemical form has been recorded in agriculture for enhancing crop yield. Most of the farmers use only nitrogen and phosphorus and not use the K fertilizer due to unawareness so that the problem of K deficiency occurs in rhizospheric soils. The K fertilizer is also costly as compared to other chemical fertilizers. Therefore, the efficient KSMs should be applied for solubilization of a fixed form of K to an available form of K in the soils. This available K can be easily taken up by the plant for growth and development. Our aim of this review is to elaborate on the studies of indigenous K-solubilizing microbes to develop efficient microbial consortia for solubilization of K in soil which enhances the plant growth and yield of crops. This review highlights the future need for research on potassium (K) in agriculture.
解钾微生物（KSMs）是一种根际微生物，能够将不溶性钾（K）转化为植物生长和产量所需的可溶性钾形式。K 的溶解是通过大量腐生细菌（粘质沙雷氏菌、土壤芽孢杆菌、环杆菌、氧化亚铁硫杆菌、类芽孢杆菌属）和真菌菌株（曲霉属和土曲霉属）来完成的。大量含有钾的矿物质（白云母、正长石、黑云母、长石、伊利石、云母）以固定形式存在于土壤中，植物无法直接吸收。如今，大多数农民为了达到最高产量而不合理地使用化肥。然而，KSMs 是溶解土壤系统中固定形式钾的最重要微生物。KSMs 是一种土著根际微生物，它在土壤和植物系统之间表现出有效的相互作用。KSMs 的主要机制是酸解、螯合、交换反应、络合和解离以及有机酸的产生。根据文献记载，目前农业中以化学形式使用的钾肥料微乎其微，这是为了提高作物产量。由于缺乏意识，大多数农民只使用氮和磷，而不使用钾肥，导致根际土壤出现钾缺乏问题。与其他化肥相比，钾肥的成本也更高。因此，应该应用高效的 KSMs 将固定形式的 K 溶解为土壤中可用的形式。这种可用的 K 可以很容易地被植物吸收用于生长和发育。我们撰写这篇综述的目的是详细阐述对本土解钾微生物的研究，以开发高效的微生物联合体来溶解土壤中的 K，从而提高作物的生长和产量。这篇综述强调了未来农业中钾（K）研究的必要性。
