A field experiment was conducted to study the effect of different application timings of P in combination with Zn and P alone on rice at Adaptive Research Farm, Gujranwala, Pakistan during the year 2010. The experimental treatments include: P application at the time of last puddling, P application just before transplanting, P application 10 days after transplanting, P application 20 days after transplanting, P + Zn application at the time of last puddling, P + Zn application just before transplanting, P + Zn application 10 days after transplanting and P + Zn application 20 days after transplanting. Different application timings of P in combination with Zn significantly reduced the sterile percentage, when application delayed which resulted in more normal kernels as compared to application of P alone and late one. Maximum abortive and opaque kernels were observed when P application was done just before transplanting. Maximum chalky kernels were perceived when P+Zn were applied 10 days after transplanting.Regarding concentration of P and Zn in rice straw and grain significant difference was observed in all treatments. The highest Zn concentration in grain and straw was observed in P + Zn application at 20 days after transplanting, while minimum Zn concentration was observed in all treatments where P alone was applied in different timings. P concentration in grain and straw was observed near seedling transplanting time more as compared to late applications of P alone and in combination with Zn. It is concluded that Zn is essential nutrient for anaerobic rice. More ever best timing for P application in rice crop is at time of last puddling. Combine application of Zn and P in rice crop at the time of last puddling, resulted in higher yield.
Keywords: Rice, Time of application, Zn, P, Yield and Qualitative Characteristics
