[Identification of a pathogenic strain of locusts and its toxicity and pathology].
A pathogen was isolated from naturally dead grasshoppers. Its pathogenicity was testified by law of KOCH. It was identified as Serratia marcescens by physiological, biochemical test and molecular systematic analysis. Toxicity of HR-3 to grasshoppers was assayed by means of oral infection. The results show that the linear regression relationship between the logarithm(y) of HR-3 concentration and the probability (x) of corrected grasshopper morality is y = 1.067 + 0.809x, and the median lethal concentration is LC50 = 1.164 x 10(8) cfu/mLo The infection mechanism of HR-3 to grasshoppers were also studied. The histopathological studies show that midgut epithelia are damaged at the beginning of infection, and then partial denaturalization and putrescence occurr in this area. After 48h infection, vacuoles appear in most regions of midgut epithelia.
Jin
Hong
H
Life Science College, Sichuan University, Chengdu 610064, China. jinh04280@yahoo.com.cn
Ge
Shao-rong
SR
Tao
Yong
Y
Ran
Hong-yan
HY
Liu
Shi-gui
SG
D000818:Animals; D004847:Epithelial Cells / Q000382:microbiology / Q000473:pathology; D006110:Grasshoppers / Q000382:microbiology*; D007422:Intestines / Q000382:microbiology / Q000473:pathology*; D012044:Regression Analysis; D012706:Serratia marcescens / Q000145:classification* / Q000302:isolation & purification / Q000472:pathogenicity*; D014774:Virulence