氮肥减量配施有机物对大白菜生长及养分利用的影响OA

[Objective]The effects of nitrogen reduction combinated with organic matter on growth and nutrient utilization of Chinese cabbage were studied to provide a reference for improvement of nitrogen utilization efficiency and efficient utilization of organic matter in cultivation of Chinese cabbage.[Method]The effects of single N fertilization(100%N),100%N+biochar(100%NB),85%N+biochar(85%NB),70%N+biochar(70%NB),100%N+commercial organic fertilizer(100%NO),85%N+commercial organic fertilizer(85%NO)and 70%N+commercial organic fertilizer(70%NO)treatments on yield,nutrient accumulation,nutrient absorption efficiency and economic benefits of CR-Wusaqianggen,a Chinese cabbage variety,were analyzed by taking no nitrogen fertilizer application as CK(0%N)and urea as nitrogen source under the same application amount of phosphorus and potassium fertilizer in Caohai Town,Weining County,Bijie City,Guizhou.[Result]The 100%NB and 100%NO treatments both could improve nitrogen accumulation in Chinese cabbage,showing a effective alternative.The nitrogen accumulation in Chinese cabbage of 100%NO treatment reached 167.47 kg/hm2.The 85%NB and 85%NO treatments both had the stable or slight increase effect on yield of Chinese cabbage.The Chinese cabbage yield of 85%NO treatment was 57 880.5 kg/hm2 and its nitrogen accumulation was comparable to that of 100%N treatment.The nitrogen,phosphorus,and potassium absorption and utilization efficiency of 85%NB and 85%NO treatment was slightly higher than that of 100%N treatment but the difference was not significant.The output value of 85%NO and 85%NB treatment was 56 559.0 Yuan/hm2 and 57 880.5 Yuan/hm2 respectively,and no significant difference with that of 100%N treatment.The Chinese cabbage yield of 70%NB and 70%NO treatment was 48 022 kg/hm2 and 48 387 kg/hm2 respectively,and lower than that of 100%N treatment.The nitrogen,phosphorus,and potassium absorption and utilization efficiency of 70%NB and 70%NO treatment was lower than that of 100%N treatment also,indicating negative substitution effect.[Conclusion]The fertilization pattern of reducing 15%nitrogen application amount+biochar or commercial organic fertilizer can ensure yield of Chinese cabbage cultivated in high-altitude and cool vegetable regions of Guizhou,and the substitution effect of commercial organic fertilizer is better than that of biochar.The optimal nitrogen application amount is 191.25 kg/hm2 in production of Chinese cabbage under the condition of applying 6 000 kg/hm2 of organic materials.