Abstract: Study on biological characteristics of sudan grass large lei spot pathogen in order to provides theoreticalbasis for further in vestigate on epidemic law and making comprehensive control measures of the pathogen. Ffect of tearperature,pH,light,nutrition conditions on vegetative growth and spore gemunation of Sudan grass large leaf spot pathogenwas studied. The results show that the pathogenic fungi could gnaw within temperature 10-35 ℃,optimal temperature was25 ℃;The suitable pH range is 5. 9-9. 0,optimal p H was 8. 0;Light gave no significant effect on the mycelium growth.PDA and the decoct juice of Sudan grass seed meal agar were optimal medium. Temperature range for spore geminationwas 10-35 ℃,optimal temperature was 20℃;pH range was 3. 0-9. 0;1%glucose solution,1%sucrose solution,1%lactose solution and 2%the decoct juice of Sudan grass seed all can increase the speed of spore germination and 1%su-crow solution was the optimal condition. Biological characters observation shows that this strain is pathogenic one withlower nutrition requirements but strong adaption ability to environment.

Key words: Sudan grass leaf spot pathogen, Exserohilumleonard turcicum(pass)Leonaral, Biological characterisncs

CLC Number: 

• S435.4