镁、钾营养及其交互作用对水稻产量、产量构成因素和养分吸收的影响

在温室条件下,采用土壤盆栽方法研究了Mg,K营养及其交互作用对水稻(Oryza sativa L.)产量、产量构成因素和养分吸收的影响。结果表明,不同Mg,K施用量均显著地影响水稻籽粒产量及其构成因素,而且Mg,K营养之间存在显著的互作效应。适量施用Mg,K肥就能显著地增加水稻产量,中Mg高K施用量的产量最高,比不施肥增产28.4%。当土壤在低K施用量时,有利于水稻植株对Mg,N和P的吸收;但在高K施用量下,则抑制Mg,N和P的吸收。在低K和中K施用量时,低量Mg能促进N,P.K的吸收,而高Mg施用量则抑制P和K的吸收。水稻秸秆Mg含量随Mg施用量的增加而增加,但随着K施用量的增加而降低。本研究表明,Mg,K营养之间存在较强的拮抗效应,Mg,K肥的平衡施用对提高水稻产量具有重要意义。

Effects of Mg, K and Their Interaction on Grain Yield and Yield Components and Nutrient Uptake of Rice

Soil pot experiment at a greenhouse was carried out to investigate the effects of interaction between Mg and K on grain yield,yield components and nutrient uptake of rice (Oryza sativa L.).The results showed that the different application rate of Mg and K fertilizers significantly affected grain yield and its com- ponents of rice.Moreover,the interactive effect of Mg and K was also significant.Moderate application of Mg and K is able to significantly increase grain yield of rice.The highest yield was obtained when the rate of middle Mg and high K was applied.The grain yield increased by 28.4% compared without application of Mg and K fertilizers.When low rate of K was supplied,the uptake of Mg,N and P in straw of rice was in- creased,but their uptake was restrained at high K rate.Under low and medium rate of K supply,the uptake of N,P and K was increased by low rate of Mg supply,whereas the uptake of P and K was depressed at high Mg rate.With an increase of rate of Mg supply,Mg uptake in straw was significantly increased,but it was greatly decreased with increasing application rate of K.The overall results confirmed that there is strong an- tagonistic effect between Mg and K.The balanced application between Mg and K fertilizers has significance on improving grain yield of rice.