早稻、大豆、油菜三熟制栽培施肥效应研究

通过一年三熟制栽培的田间定位施肥试验 ,探讨水稻、大豆、油菜对不同施肥的反应及土壤养分的变化。试验结果表明 ,在低丘马肝泥水稻田三熟条件下每季施N 75kg/hm2 ,P2 O53 7.5kg/hm2 ,K2 O 75kg/hm2 ,稻、豆、油全年增产效果显著 ,增产 3 65 2 .5kg/hm2 ;不同作物施肥的增产效果是油菜 >水稻 >大豆 ;几种施肥处理的单位面积油分、蛋白质产量增加 ,尤其是NPK、NP、P区的油菜蛋白质及油分产量较CK增加 2 .8～ 3 .7倍 ;连年定位施肥对大豆、油菜成熟期植株体养分含量的影响较大 ,不同的施肥处理和作物不同的器官均不相同 ;经 4年施肥后的不同施肥区的土壤全N、P、K含量变化不明显 ,而速效态养分则随不同肥料处理有较大变化。

Fertilization Experiment in Paddy Fields under the Cropping System of Early Rice,Soybean and Rapeseed

Reaction of rice, soybean and rapeseed to various fertilization combinations under the cropping system of early rice-soybean-rapeseed was investigated,in which, the fertilization combinations in each plot were kept at the same for four years. For the paddy fields in low hilly regions,the combination of 75?kg N, 37.5?kg P_2O_5 and 75?kg K_2O could significantly increase yield of all the three crops, totally by 3?652.5?kg/hm2.Yield increase ratio was highest in rapeseed followed by the cropping system of rice and soybean. Beside productivity of the grain, the oil and protein content also had a positive reaction to fertilization. The nutrients in soybean and rapeseed in matured plants were different in different treatment. After four years continuous fertilization, the total N, P and K contents in soil were similar among different plots while the nutrient availability varied much with fertilization treatments.