Studies On Seed Production Technology Of Hybrid Rice By Mixed Planting

The variety Hunzhi No.1 was breeded by the Green Food Institute of Anhui Academy of Agricultural Sciences, and its male parent took the sensitive gene which was killed by herbicide Bentazon. Its male parent can not set seed by itself if spraying Bentazon at heading stage in the hybrid rice, but the female parent could as it didn't took the sensitive gene. It could obtain high output and regular quality hybrid seed either sow by hand or by machine. It also could ensure the quality of the hybrid seed, predigest working procedure, save labor and save cost by mixed panting breeding compared with traditional breeding. The method is an innovation. This research had studied the comprehensive breeding and purity test technology. The results were as follows.1. It could lead the male parent to fade and die after blossom by spraying 350 ml 48% bentazon added 45 kg water per 667m~2 on the leaves at heading stage. The male parent's seed setting rate was only about 0.7%. The seeds were semideveloped and couldn't germinate.2. The best rate of male and female parent was 1 I 5 in mixed panting breeding. The rates of spike and flower of male and female parents were 1 :4.3 and 1 : 3.5, respectively. The hybrid seed setting rate of female parent was high and the theoretical and ideal outputs were all 451.7kg/667m~2.3. The quality of the seed was high in mixed planting breeding. The seeds were plump and germinate well, and the germinate rate was 94.3%～96.3%. The 1000 grain weight was 20.8g～21.7g. The self cross seed setting rate of male parent is very low and the germinate rate was only 0.1～0.2%.4. The better sow time of Hunzhi No.1 was around May 27th. The first heading time of male and female parents were August 18th and August 16, respectively. This was the best time for hybrid breeding.5. It could ensure the seed purity by coating 0.24% bentazon or spraying 300ml 25% bentazon 300ml added 45kg /667m~2.