紫云英还田与化肥减施对早稻影响的综合评价

Comprehensive Evaluation of Effects of Chinese Milk Vetch Returning to Field and Chemical Fertilizer Reduction on Early Rice

为了探究紫云英还田与化肥减施对早稻的综合影响,设置不施肥(CK)、100%化肥(F_(10))、化肥减量20%+翻压不同量(15000、22500、30000 kg/hm^(2),分别记作G_(10) F_(8)、G_(15) F_(8)、G_(20) F_(8))的紫云英等5个处理,通过田间定位试验,研究了种植紫云英及不同还田量对早稻产量、品质、养分吸收、土壤养分等的影响。结果表明,紫云英配施化肥处理有降低早稻垩白和增加整精米率的作用,减量20%化肥+紫云英还田22500 kg/hm^(2)处理在保障早稻产量的同时能有效增加稻米整精米率和降低垩白。籽粒含P量与精米率、整精米率、蛋白质含量呈显著正相关;籽粒含N量与糙米率、精米率、整精米率、垩白粒率、蛋白质含量呈显著正相关,与碱消值、直链淀粉含量呈显著负相关;籽粒含Si量对早稻品质的影响效应与籽粒含N量相反。土壤交换性镁含量对糙米率、蛋白质含量具有间接正效应,对直链淀粉含量具有间接负效应;土壤有效磷含量对垩白度具有间接负效应;土壤有效磷含量对整精米率,以及土壤全磷含量对糙米率均具有间接正效应。南方紫云英还田+增施硅、镁、磷肥处理对早稻品质具有潜在的改善作用。

In order to explore the comprehensive effects of Chinese milk vetch returning to field and chemical fertilizer reduction on early rice,five treatments were set up,including control CK(no fertilizer),treatment F_(10)(100%chemical fertilizer),treatment G_(10) F_(8),G_(15) F_(8),and G_(20) F_(8)(reducing 20%chemical fertilizer with retention amount of 15000,22500 and 30000 kg/hm^(2) Chinese milk vetch respectively).The effects of Chinese milk vetch and different returning amount on yield,quality,nutrient absorption and soil nutrients of early rice were studied by long-term field experiment.The results indicated that Chinese milk vetch retention combined with chemical fertilizer had a good effect of increasing head rice rate and reducing chalkiness degree and chalkiness grain rate of early rice.Even when reducing 20%chemical fertilizer it could effectively increase head rice rate and reduce chalkiness of early rice on the premise of ensuring the production.The P content of grain was significantly and positively correlated with the milled rice rate,the whole milled rice rate and the protein content of grain.The N content of grain was positively correlated with the brown rice rate,the milled rice rate,the whole milled rice rate and the protein of grains,but was negatively correlated with the alkali extinction value and the amount of amylose.However,the effect of Si content in grain on rice quality was opposite to that of grain N content.Soil exchangeable Mg had an indirect positive effect on protein and brown rice,but an indirect negative effect on amylose.The effect of soil available P on chalkiness was indirect negative,but the effect of available P on head rice rate and total P on brown rice rate were indirect positive.It is suggested that the quality of early rice could be improved by improving cultivation measures and applying silicon,magnesium and phosphorus fertilizer.