The experiments used orthogonality design with three replications .
试验采用正交设计，重复三次。
The orthogonality of laguerre polynomials and related problems .
laguerre多项式的正交性及其相关问题之研究。
Based on the previous screenhouse study and field experiment , fertilization , plant variety and plant density were studied on two selected cropping systems : rape-rice-rice and wheat-rice , using an orthogonality design .
