Central Arid Zone Research Institute, Jodhpur, 342 003 India.
Indian J Microbiol. 2007 Mar;47(1):57-63. doi: 10.1007/s12088-007-0011-0. Epub 2007 Jun 14.
Phosphate solubilizing microorganisms are ubiquitous in soils and could play an important role in supplying P to plants where plant unavailable P content in soil was more. A phosphatase and phytase producing fungus Emericella rugulosa was isolated and tested under field condition (Pearl millet as a test crop) in a loamy sand soil. In the experimental soil 68% organic phosphorous was present as phytin; less than 1% of phosphorous was present in a plant available form. The maximum effect of inoculation on different enzyme activities (acid phosphatase, alkaline phosphatase, phytase, and dehydrogenase) was observed between 5 and 8 weeks of plant age. The depletion of organic P was much higher than mineral and phytin P. The microbial contribution was significantly higher than the plant contribution to the hydrolysis of the different P fractions. A significant improvement in plant biomass, root length, seed and straw yield and P concentration of root and shoot resulted from inoculation. The results suggest that Emericella rugulosa produces phosphatases and phytase, which mobilize P and enhance the production of pearl millet.
解磷微生物广泛存在于土壤中,在植物可用磷含量较低的土壤中,它们可能在为植物提供磷方面发挥重要作用。本研究从土壤中分离并筛选出一株产植酸酶和磷酸酶的真菌—— rugulosa,并在砂壤土中进行田间试验(以珍珠粟为试验作物)。在实验土壤中,68%的有机磷以植酸的形式存在;只有不到 1%的磷以植物可利用的形式存在。接种后,不同酶活性(酸性磷酸酶、碱性磷酸酶、植酸酶和脱氢酶)的最大影响出现在植物 5-8 周龄之间。有机磷的消耗远高于矿物磷和植酸磷。微生物对不同磷形态的水解作用的贡献明显高于植物。接种显著提高了珍珠粟的生物量、根长、种子和秸秆产量以及根和茎的磷浓度。这些结果表明 rugulosa 产生的植酸酶和磷酸酶可以动员磷,从而提高珍珠粟的产量。