Relationship Between Population Quality And Yield Of Different Rice Varieties

Rice population quality index is a concept that was proposed in 80s of last century and was used for valuing the harmony development of individuality and population. This experiment was conducted with 30 rice varieties and the validity ear, grain per ear, setting percentage, grain weight, leaf area index, dry matter accumulation, spikes of unit leaf area, weight of per plant, plant height and yield were determined and their relationships with yield were analyzed by path analysis. The results were as follow: 1. Comparison of yield components and population quality(1) Comparison of yield componentsThere was much difference of yield components among the 30 rice varieties, the varieties of No.24, No.25, No.30 and No.23 obtained higher yield than the others and their yield components were greater than the others as well.The validity ear and setting percentage of early maturity varieties were greater but grain per ear and grain weight were lower than late maturity varieties.(2) Comparison of population quality indexThere was much difference of population quality indices among the 30 rice varieties; plant height, weight of per plant, leaf area index, dry matter accumulation and spikes of unit leaf area of the varieties of No.23, No.24, No.25 and No.30 were greater than the others plant height, weight of per plant, dry matter accumulation and spikes of unit leaf area of early maturity varieties were significantly greater than those of late maturity varieties; leaf area indices of late maturity varieties were sinificantly lower in tillering stage, higher in heading stage and no significant difference in maturity stage comparing with early maturity variety.2. Correlation analysis of yield components, population quality and yield(1) Correlation analysis of yield components and yieldThe correlation indices of the validity ear, grain per ear, setting percentage and grain weight with yield of 30 rice vaaieties were not significant.The relationship between the validity ear and grain per ear of both early and late maturty varieties were negative correlation, the correlation index of late maturity variety was signifant and greater than that of early maturity variety.The correlation indices of grain per ear with setting percentage, grain weight and yield of early maturity varieties were greater than those of late maturity varieties. The correlation index of grain weight with yield was significant and greater than the early maturiy variety.(2) The correlation analysis of population quality and yieldThe relationship of leaf area index with spikes of unit leaf area was negative correlation, while positive correlation with dry matter accumulation, weight of per plant, plant height and yield. The correlation index of weight per plant and plant height was significant; The relationships of spikes of unit leaf area with weight per plant, plant height and yield were negative correlation, while it was positive correlation of weight per plant with plant height and yield and the correlation index of weight per plant with plant height was significant; the correlation index of plant height with yield was significant.The leaf area index of both early and late maturity variety had similar correlation with other population quality indices; The dry matter accumulation of late maturity variety had significant positive correlation with spikes of unit leaf area, weight per plant, plant height and yield, while the dry matter accumulation of early maturity variety had only significant positive correlation with yield and no significant correlation with other population quality indices; the spikes of unit leaf area of both early and late maturity varieties had positive correlation with weight per plant, plant height and yield but only with yield reached significant level; the correlation indices of weight per plant with plant height and yield of early maturity variety were no significant, while it was significant with plant height and no significant with yield of late maturity variety; the correlation indices of plant height with yield was significant in early maturity variety and no significant in late maturity variety. 3 Path analysis of yield components, population quality indices and yield with different rice typesThe direct effects of validity ear, grain per ear, setting percentage and grain weight on the yield early maturity variety were significant greater but less indirect effects than those of late maturity variety; the direct correlation of leaf area index with yield of both rice types were significant and were greater than indirect correlation; the direct correlation of spikes of unit leaf area with yield was less in early maturity variety but greater in late maturity variety compared with the indirect correlation; the direct and indirect correlation indices of weight per plant with yield were 0.274 and 0.254 respectively in early maturity variety, while they were -0.33 and 0.826 respectively in late maturity; the direct correlation of plant height with yield was less than indirect correlation in both rice types.