Dynamic Characteristics of Matter Population in Two Super Hybrid Rice Cultivars

Abstract

In order to find foundations of high-yield cultivation in super hybrid rice(SHR), we modeled on dynamics of population indices. A field experiment with two super hybrid rice cultivars(Zhunliangyou 527, Q you 6) and control(II you 838) was conducted in 2011 and 2012, and dry matter accumulation(DMA) and leaf area index(LAI) were measured. The dynamic equations of DMA and relative leaf area index(RLAI) were established and the dynamic characteristics of crop growth rate(CGR),relative growth rate(RGR), leaf area duration(LAD), net assimilation rate(NAR), and specific leaf area(LAR) were analyzed based on the equations. The DMA and its proportion to the total biomass at rapid growth stage were significantly higher than those of Control. In the process of time after transplanting, the tendency of CGR was expressed in a single peak curve, and CGR of two SHR was higher than that of control in rapid growth stage. The RGR of Zhunliangyou 527 was higher than that of control from 23d after transplanting to mature period. As compared with the RGR of control, the RGR of Q you 6 was lower before 43 d after transplanting, higher from 43 d to 113 d after transplanting, and not much difference from 113 d after transplanting to maturity. A significant correlation was observed between gross LAD and LAD at rapid growth stage, and also between gross LAD and duration of LAI at rapid growth stage. Compared with Control, the RGR of SHR showed faster increasing and decreasing, and its peak value was higher. A single peak curve was available for the dynamic changes of NAR with its most high value from 43 d to 53 d after transplanting. The LAR of two SHR decreased fast from 23 d to 43 d after transplanting, moderately from 73 d to mature stage, and slowly from 43 d to 73 d after transplanting stage. The LAR of two SHR was higher in rapid growth stage than that of control.