增产菌对棉花苗期病害的抑制效果及其机制的研究

Effect and Mechanism of YIB Inhibiting Seedling Diseases on Cotton

在棉田覆膜栽培和温室盆栽条件下,对增产菌抑制棉苗病害的效果和机制进行了研究。增产菌处理过的田块,棉苗根病减轻8.8—9.2％,复合死苗率减轻43.4％。其机制为:根际微生物群落发生变化,导致害菌减少益菌增加,而且植株体内的过氧化物酶活性及其同功酶活性增强,同功酶还出现二条新谱带;再者根际土壤酶活性也增强,提高了土壤速效养分的供应。

This experiment had been done under the condition of plastic-sheet-covered cultivation in the fields. YIB was used in the treatment. (Yield Increasing Bacteria Here were Bacillus cerus and B. firmus), but YIB was not used in the controls. The results indicated that the diseases on cotton seedling in the fields with YIB had declined by 8.8％—9.2％, and the complex dead rate decreased by 43.3％ compared with that in the controls. Changes in the microflora on plant surfaces led to a decrease in deleterious fungi and an increase in beneficial fungi in comparison with the control plants, and the peroxidase and its isoenzyme were shown to be more strengthened in the treated plants than in the control plants and new girdles appeared in peroxidase-isoenzyme. The activation of soil nutrient enzymes became enhanced, too, in the treated fields, thus making the contents of readily available fertilizer higher.