Study On Application Rate And Ratio Of Chinese Milk Vetch And Chemical Fertilizer In Paddy Fields In Honghu, Hubei Province

To made clear the suitable amount and ratio of green manure and fertilizer in paddy field in Honghu, Hubei province, the effects of applying Chinese milk vetch with different amount of fertilizer and applying different amount of Chinese milk vetch on rice growth, yield and nutrient uptake and soil fertility was investigate under the field experiment in two consecutive years, The main results were showed as follow:(1)Applying22500kg/hm2of green manure combined with40%or60%less fertilizer than local grower, rice yield was no significant different with single100%fertilizer. The effect of green manure replacing40%fertilizer in2012and60%fertilizer in2013were the best, the rice yield was increased by473.66kg/hm2,50.41kg/hm2, respectively, the rice economic benefit was increased by1170yuan/hm2,491yuan/hm2, respectively.(2) Applying22500kg/hm2of green manure combined with60%or80%fertilizer in paddy field, the accumulation of nitrogen and potassium in shoot of rice was higher than that of single100%chemical fertilizer treatment, but that of phosphorus was not significantly different between them.(3)According to the experiment in the past two years, the rice yield was increased when more green manure was applied and no fertilizer was applied. When30000～45500kg/hm2of green manure was applied, rice yield was similar to that of100%fertilizer. Rice yield was not decreased when11250～22500kg/hm2of green manure combined with30%less fertilizer than local was applied. There is no negative effect on rice production even if excessive green manure (45000kg/hm2) was applied with100%fertilizer.(4) The accumulation of nitrogen, phosphorus and potassium in shoots in rice was increased gradually when more green manure was applied in rice field without fertilizer. When100%or70%of fertilizer was applied, those were not obvious regular as of the application of green manure was increased.(5) Whatever applying green manure with different amount of fertilizer or applying different amount of green manure, the content of organic matter, total nitrogen, available phosphorus and available potassium in rice field was not significant different in the current season.