Studies On Techniques Of Seed Production And Seed Quality Control Of Two-line Hybrid Rice In Two-line Early Rice Combination Luliangyou996

Two-line system heterosis has made important progress and achievements on rice in China, which made important contribution to rice production and food security. Two-line hybrid rice seed production technology plays an important role in the application of two-line hybrid rice. Based on actual production and combined with years of practical experience, this study investigated the seed quality control problems of the two-line hybrid rice. The thermo-sensitive characteristics on the parents, the plant density and fertilization techniques on male parent of Luliangyou996were studied. The main results are as follows:(1) The characteristics of sensitive to temperature of super hybrid rice Luliangyou996’parent was studied and discussed in this paper. The temperature sensitive level of R996was six, which was classified as medium temperature sensitive variety. The temperature sensitive level of Lu18S was seven, which was classified as strong temperature sensitive variety. It indicates that the characteristics of sensitive to temperature between R996and Lu18S have some difference.(2) The experiment of plant density and fertilization techniques on male parent of Luliangyou996showed that2-4seedlings per hill of the female parent can insure high-yielding grain structure.4-6plants of the male parent can not yet reach the high-yielding grain structure on hybrid seed production of Luliangyou996, so the basic seedlings and top dressing should be increased. The different fertilization level experiment showed that the ideal processing is the treatment E.(3) The causes of seed quality risk on two-line hybrid rice was pointed out, which include the characteristics of the varieties, the improper choice of seed production area, the unreasonable arrangement of the flowering time, abnormal weather and quality control measures seed production process are not implemented. In this paper, strategies and measures on two-line hybrid seed production have been put forward based on many years’ practice. Selecting dual-purpose genic male sterile line with lower critical sterility-inducing temperature can minimize the risk in seed pruduction of two-line hybrid rice. Scientifically selecting a suitable site and safe duration is the key strategy to ensure the seed production safety of two-line hybrid rice. Strengthen enterprise management and establishment of a scientific quality management system is also needed.