| The yield of hybrid rice seed production is affected by the difference of outcrossing habits of Male sterile lines, and the process of seed production has become a key link restricting the promotion of three-line hybrid rice.【Objective】In order to provide a new way to improve the yield of reproduction and seed production, the effects of five types of male sterile cytoplasm and fertilizer regulation techniques on the outcrossing habits of male sterile lines in hybrid rice were studied.【Method】The nucleo-cytoplasmic interactive sterile cytoplasm of W-type, JW-type, G-type, K-type and YS-type were
selected to construct isonuclear-alloplasmic male sterile（CMS）lines. The outcrossing habit and reproductive yield of CMS lines were studied under different nitrogen fertilizer treatments with a view to explore the influence of cytoplasmic effect on the outcrossing ability of male sterile lines and its fertilizer regulation me chanism.【Result】The increase of reproductive yield of each isonuclear-alloplasmic CMS line was mainly controlled by the increase of effective panicle number, 1 000-grain weight and seed setting rate. Under the condition of 10 kg / 667m2 nitrogen fertilizer, the reproductive yield of JW and W CMS lines reached the highest, 259.20 kg / 667m2 and 244.04 kg / 667m2, respectively; while the yield of GA, KA and YSA could reach 250 kg / 667m2 with 18 kg / 667m2 nitrogen fertilizer, but there was a high risk of diseases and pests.【Conclusion】Cytoplasmic effect and its interaction with nitrogen fertilizer had significant effects on the main agronomic characters and outcrossing habits of CMS lines. The effect of nitrogen level on agronomic traits and reproductive yield of CMS lines was greater than that of cytoplasmic effect. Cytoplasmic effect mainly affected outcrossing habits of CMS lines such as stigma exposure. |
