Effects of rice transplanting density and early irrigation management on barnyardgrass ecological control.;

In order to research the application feasibility of 48% Butralin EC of aniline herbicidesn in the north transplant rice field,the trial of 48% Butralin(EC) on weeds was done to study the herbicide controlling spectrum,weeding effect and safety on rice growth.

The research chose three testing factors,which were transplanting density,the amount of topdressing urea and the distributive proportions of urea as tiller fertilizer and spike\]et-developing fertilizer under their treated amounts,adopting simplex-lattice design and setting field parameter tests.

The results show that transplanting density greatly affects the establishment of a rapid growing high-yielding colony.

The field experiment was conducted by split-plot design of two factors to study the effects of applying amount of controlled-release nitrogen fertilizer(SCU) and transplanting density on the growth and development and yield of the medium super hybrid rice combination Y Liangyou 1,and the mathematical model of yield to nitrogen rates and transplanting densities was set up.