杂交稻制种与稻粒黑粉病发生的关系研究

SEED PRODUCTION OF HYBRID RICE AND THE RELATIONSHIP BETWEEN RICE KERNEL SMUT AND ITS HOST PLANT

１９８９～１９９２年采用控制性试验和田间调查相结合，研究了稻粒黑粉祸发生与水稻授粉的关系。结果表明，在已授粉后，制种稻粒黑粉病病粒率和侵染率随侵染时间的推迟而下降。授粉受精和病菌侵染基本同步时才能形成病粒。自花授粉对稻粒黑粉病有防御机制。病粒率、侵染率与恢复系花粉量呈负相关。不育系外露柱头增加的健粒数约为病粒的１０倍。制种稻粒黑粉病的防治，是以化学防治为主的综合防治。

The relationship between the epidemic of rice kernel smut(Neovossia horrida)and its host plantwas studied in controlled experiments and field investigations in 1989-1992.The smutted grainrate and the i nfection rate of male-sterile rice kernel smut decreased greatly with the delay ininfection time after poflination in hybrid seed producing fields and they showed a significant nesativecorrelation with the pollen count of the restorer.Smutted grain were formed only when infection ,pollination and fertilization occurred nearly synchtonously.A resistanee meehanism to kernel smutexisted in self-pollinated rice.The healthy grain rate increased by protruding styles of the malesterile rice varieties was about 10 times greater than smutted grain rate.Integrated management ofrice smut kernel with fungicide application as the key link is offered as the control strategy.