不同施肥结构对甘蓝物质积累与养分吸收的影响

Effects of Different Fertilizations on Substance Accumulation and Nutrient Uptake of Cabbage

通过大田小区试验,研究了洞庭湖平原的冲积性菜园土条件下不同施肥结构对甘蓝生育期间的物质积累、甘蓝对N、P、K养分的吸收规律以及土壤有效N、P、K养分的动态变化。结果表明,甘蓝超过50%的物质积累以及的N、P、K的吸收均集中在移栽后的第30天到第80天的生长旺盛期;各施肥处理甘蓝对N、P、K的吸收比例为N∶P2O5∶K2O=1∶0.19∶0.72,对N、K要求较多,P素需求量最低;经一季作物栽种后,土壤肥力有不同程度的下降,其中K素耗竭,土壤通过释放非交换性K补充K源提供作物生长需要。因此在农业生产中要注意生长旺盛期的肥料尤其是K肥补充。

Field and plot experiments were carried out to study on dynamic changes of substance accumulation of cabbage, N, P, K nutrient uptake and soil nutrient content at different growth stages affected by various fertilizations under the alluvial vegetable soil in Dongting Lake Plain. The results showed that over 50% substance accumulation and N, P, K nutrient uptake of cabbage mainly appeared in the middle vigorous growth period from the 30^th to 80^th days after transplanting. The ratio of N： P2O5： K2O absorbed by cabbage under four fertilizer treatments was 1： 0.19： 0.72. It demonstrated that cabbage demanded much more N and K than P. After a planting season, each nutrient element decreased by different levels, but K exhausted for soil would release non-exchangeable K to supply the demands of plant. Therefore, attention must be more paid to the K fertilizer supplement in the vigorous growth period.