氮肥形态及氮钾施用措施对水稻生长 和养分吸收的影响

为探明不同氮(NH_4-N和NO_3-N)源下,不同施钾水平及氮钾施用次序对水稻生长和养分吸收的影响,进行了温室盆栽试验。结果表明:在水稻生长早期(20d左右时),以NO_3-N作为N源时水稻的生物产量和氮钾养分吸收量均显著高于NH4-N作N源的处理,但随着生长时期的延长,NH4-N源更能促进水稻的生长和养分吸收,因此,从整个营养生长时期来讲,铵态氮肥作为水稻N源更具有优越性。结果同时表明,氮肥施用效果与钾肥的施用水平有很大关系,在一般盆栽试验氮肥用量(纯N用量0.15g/kg)水平下,施钾(K2O)量达到0.51g/kg时会导致水稻的生长及养分吸收量显著下降。铵钾施用次序对水稻的营养生长及养分吸收均有一定的影响,特别是施钾量较高时,铵钾在土壤中的交互作用会导致水稻因氮素供应不足而影响生长和养分吸收。

Effect of N Varieties Application and Interaction of N and K Fertilizers on Rice Growth and Nutrients Uptake

In order to explore the effect of N (NH_4-N and NO_3-N) and K interaction on the growth and nutrients uptake of rice, rice pot experiment was conducted. The results displayed that the amount of dry matter and nutrients taken up by rice with NO3-N application were larger than that with NH4-N application in the early growing period of rice (20 days of growth). But with the increase of growth period, the application of NH4-N was demonstrated to be much more beneficial to the growth and nutrients uptake of rice. In addition, the rate of K applied was perceived to have influence on the effect of N fertilizer application. The growth and nutrients uptake of rice could be largely lessened by the application of K (K2O) with a rate of 0.51 g/kg, when the N rate was 0.15 g/kg. The sequence of N and K application also could have influence on rice growth and nutrients uptake, especially when high rate of K applied, which could result in the reduce of rice growth and nutrients uptake caused by the decrease of available N in soil.