Opportunism of Conidiobolus obscurus stems from depression of infection in situ to progeny colonies of host alatae as disseminators of the aphid-pathogenic fungus.
Opportunism of Conidiobolus obscurus stems from depression of infection in situ to progeny colonies of host alatae as disseminators of the aphid-pathogenic fungus.
复制标题
DOI：
10.1111/j.1462-2920.2007.01346.x
复制
发表时间：
2007
影响因子：
5.1
通讯作者：
Guo-zhong Zhang;M. Feng;Chun Chen;S. Ying
中科院分区：
文献类型：
--
作者：
Guo-zhong Zhang;M. Feng;Chun Chen;S. Ying
孢子虫包括常见的蚜虫病原体，但在世界范围内引起散发性真菌病。这种流行病学上的机会主义是通过研究513种桃蚜的后代菌落传播真菌病的可能性来探讨的。桃蚜是隐孢子虫的传播者，经常感染蚜虫。将孢子雨暴露的孢子虫在飞行机上飞行2.05 (0.01 ~ 8.95)km，然后在20 ~ 23℃的条件下，在白菜上单独饲养14天。所有真正感染的菌株均在6天内产生真菌，平均产生3.9（0-15）个若虫，而未感染的菌株同期平均产生11.6（0-35）个若虫。继发性和第三次感染分别仅发生在16.2%和4.8%的真菌菌落中，这是由于60%的尸体形成静止孢子。定植后4 ~ 8 d以传染性感染为主，11 d以后不再发生传染性感染。菌落大小（最后一天平均51.5只）和真菌传播（第6天最高6.3%）的趋势分别符合logistic （r2 = 0.99）和Gompertz生长模型（r2 = 0.91）。结果表明，隐球菌的机会性源于宿主传播后的传染性感染抑制，表明隐球菌的机会性被其他非静止真菌的流行所压倒。
Conidiobolus (Entomophthorales: Ancylistaceae) includes common aphid pathogens but causes sporadic mycosis worldwide. This epizootiological opportunism was explored herein by examining the potential of mycosis transmission in the progeny colonies of 513 Myzus persicae alates as disseminators of C. obscurus often infecting aphids. The alates exposed to spore showers were flown for 2.05 (0.01-8.95) km on flight mills and then reared individually on cabbage at 20-23 degrees C for 14 day colonization. All truly infected alates were mycosed within 6 days and averagely left 3.9 (0-15) nymphs while those uninfected produced 11.6 (0-35) nymphs during the same period. Secondary and tertiary infections occurred only in 16.2% and 4.8% of the progeny colonies of the mycosed alates respectively, due to c. 60% of the cadavers forming resting spores. Most of the contagious infections appeared on days 4-8 after colonization and no more occurred from day 11 onwards. Trends of colony sizes (last-day averaging 51.5 aphids) and mycosis transmission (sixth-day maximum 6.3%) fit well to logistic (r2 = 0.99) and Gompertz growth models (r2 = 0.91) respectively. The results confirm that the opportunism of C. obscurus stems from depression of contagious infection after dissemination by host alates and suggest that it be overwhelmed by the prevalence of other non-resting fungal species.