| The effect of azotobacter fertilizer on living activity, soil fertility, yield, total nutrient and crop quantity is studied at the different level of using nitrogen .in the calciform soil by the rape potted plant biology analogue experiment, in order that the best scope of valid applying azotobacter fertilizer is determined. It can offer theoretic basis for searching ways of biology controlling to high yields and qualities, optimization directions for products of special compound fertilizer and valid using. The results are as follows:1.Within the scope of 0.05-0.20g/kg of using nitrogen for the azotobacter fertilizer in the soil, the content of azotobacter, P bacteria and K bacteria in the soil averagely increases 41.0%-57.5%, and the content of bacteria, fungus and ray-fungus averagely increases 53.9%-96.8% because of using the azotobacter fertilizer. It shows that the effect of azotobacter fertilizer on the whole grown period is bigger.2.The effect of azotobacter fertilizer on SMB-C is more significant at middle-after grown period, and the effect of SMB-N is more significant at prophase.3.The content of Total N , Dissolving N, Available P and Available K in the soil respectively increases 152.9%,13.3%,8.3% and 0.8% because of using the azotobacter fertilizer. It shows that the fertilizer can also increase the content of soil nutrient.4. Fresh heavy, dry heavy, plant height and root length of Cole respectively increases 8.3%,10.7%,9.4%,9.1% comparing with the area of reference because of using the azotobacter fertilizer. Especially, the increase of these indexes of Cole is the most at the level of 0.15g/kg of using nitrogen, and respectively increases 19.9% , 18.8%, 21.2%, 14.4%.5.The content of Total N, Total P and Total K of Cole respectively increases 16.8%, 20.7%, 8.5% comparing with the area of reference. The content of these indexes of Cole respectively increases 23.4%, 27.6%, 16.4% at the level of 0.15g/kg of using nitrogen, which makes nutrient increase most.6.The content of VC, chlorophyll and protein of Cole respectively increases 10.3%,20.7%,16.8% comparing with the area of reference, while the content of nitrate averagely reduce 53.5%. It show that the azotobacter fertilizer makes the quantity of the Cole improve effectively.In a word, the effect of azotobacter fertilizer on living activity, soil fertility and crop quantity is Significant within the scope of 0.05-0.20g/kg of using nitrogen in the soil, and the effect is most prominent at the level of 0.15g/kg of using nitrogen. It show that the best scope of valid applying azotobacter fertilizer is0.15g/kg. |
