油菜干物质积累和养分钾、磷、硫吸收特点及施钾的影响

采用微区试验研究油菜干物质积累和养分钾，磷，硫吸收特点及施钾的影响。结果表明：（1）油菜地上部干物质积累量呈快速增长趋势，地下部干物质积累量增长平缓，施钾明显提高油菜植株干物质积累量。（2）苗期植株地上部钾，磷和硫含量最高，越冬期迅速降低，生育后期地下部钾和磷含量下降较快，成熟期达最低值。（3）施钾明显提高植株钾含量，但施钾对磷和硫含量的影响较小。（4）生育后期地上部出现明显的钾，磷和硫吸收高峰，结角－成熟期地下部磷吸收下降。施钾明显提高油菜植株钾，磷和硫的吸收量。

Characteristics of dry matter accumulation and K, P and S absorption in rapeseed and the effect of K application

Characteristics of dry matter accumulation and nutrients K, P and S absorption in rapeseed and the effect of K application on the above characteristics in different growth stages were studied by micro-plot experiments. Results showed that (1) The dry matter of shoot accumulated quickly, while that of root accumulated in a mild rate, which was greatly increased by K application. (2) The content of K, P and S in rapeseed shoot was the highest in seedling stage, and then decreased rapidly until early wintering stage. The content of K and P in rapeseed root reduced obviously in later growth stage and the minimum value appeared in maturity stage. (3) There was a good effect of K application on increasing K content of plant, while a rather small effect of K application on P and S content plant. (4) The absorption of K, P and S in shoot increased distinctly in later growth stage, whereas that of P in root decreased during podding-maturity stage. K application improved the absorption of K, P and S in rapeseed.