Effects Of Different Row Ratio And Density On Hybrid Rice Seed Production Yield Formation

In the female parent seedling number and row ratio between parental lines are two important factors to affect the seed production of hybrid rice. The hybrid rice yield formation was basis on the effective use of photosynthesis and solar radiation. At present, there was very few research about Hybrid Rice Seed Production Yield Formation by photosynthetic characteristics and optical radiation mechanism. In this study, the field tested was located in Yongan town, Liuyang City, Hunan province. In 2014 year summer solstice, we selected the ?-32A and R416 hybrid rice combinations to analysis seed production yield formation, and in a split plot design, row ratio between parental lines(1 row male parent Ml,2 rows male parent M2 and 3 rows male parent M3, 12 rows female parent) was assigned to main plot and female parent seedling number(the density from low to high was D1? D2?D3) to the subplot to investigate the RUE, dry matter formation, different photosynthetic organs of Photosynthetic Characteristics for hybrid rice yield formation of cultivate physiological basis. Analysis the female parent seedling number and row ratio between parental lines formed different seed production population canopy layer of photosynthesis and light utilization characteristics and radiation on influence the seed production yield formation. In order to provide theoretical and technical support to improve the yield of hybrid seed production. The main results are as follows:(1)hybrid rice seed production of F1 yield increases with female parent seedling number and row ratio between parental lines increases, So M3> M2> M1, M3 than M2 and M1 increased by 12.1%,52.6%, respectively; while D3> D2> D1, D3 and D2 had significant difference than D1. D2 and D3 had not significant difference. And on the M3D3 condition, the yield was largest,3.10 t.hm-2, significantly higher than M1D2, M1D1, M1D3, M2D2, M2D1 and M3D1, the M2D3 and M3D2 had not significant difference. Combined with the yield component factors to further analysis, on the female parent seedling number and row ratio between parental lines increases condition, the female parent of out crossing rate and filled grain number per panicle had a very significant.(2) The female parent seedling number and row ratio between parental lines had a very significant difference the amount of solar active radiation intercepted by the female population in each period, but the radiation use efficiency was not significant. As on the female parent seedling number and row ratio between parental lines increased condition, it significantly increased the amount of solar active radiation interception, while correlation analysis showed that the yield and the amount of solar radiation intercepted effective was a significant positive correlation (r = 0.4093*), associated with the utilization of radiation had not significant correlation, This result can indicate that the hybrid rice seed production process of the female parent population photosynthetically active radiation intercepted play a key factor in the amount of seed yield.(3)The female parents harvest index and grain-leaf ratio with In the female parent seedling number and row ratio between parental lines increase, and both with yield had a significant positive correlation, the coefficient was r = 0.8751** and r = 0.7308**.So the result showed that in the hybrid rice seed production process, by increase the female population to further improve harvest index and grain-leaf ratio, it was the key to improve seed production.(4) The female parents population of different photosynthetic organs had an important impact on the photosynthetic rate and yield contribution rate. At full heading the organ of photosynthetic rate from high to low as follows:flag leaf> panicle> stem, After 20 days heading stage, the organ of photosynthetic rate from high to low as follows:flag leaf> stem >panicle, with the growth of rice, stem sheath of photosynthetic rate decrease amplitude was smaller than the flag leaf and ear. The Photosynthetic organs of contribution rate to yield as follow:flag leaf> ear> stem, leaf,fringes and stem contribution rate was 38%,32% and 30%, respectively. And as the density increases tassel contribution rate was increasing, and with the increase of leaf and stem density decreases, while the yield difference between the contribution rates of leaves, stems and ears was not significant, stem and sheath and ears in the case of female high-density photosynthetic products transplanting late production play a very good complement,So the result can indicate the contribution rate of photosynthetic capacity of ear and stem to the hybrid rice seed yield can not be ignored.Conclusion:In hybrid seed production process, by increasing the row ratio between parental lines can improve population of the amount of radiation intercepted, harvest index, and grain-leaf ratio, and it can significantly improve seed production, in addition, the non-leaf organs (ears and stem) of photosynthetic capacity strengthen also can improve seed production.