Fungal and Viral Epizootics in Gypsy Moth (Lepidoptera: Lymantriidae) Populations in Central New York
Fungal and Viral Epizootics in Gypsy Moth (Lepidoptera: Lymantriidae) Populations in Central New York
复制标题
纽约中部舞毒蛾（鳞翅目：舞毒蛾科）种群中的真菌和病毒流行病
DOI：
10.1006/bcon.1997.0541
复制
发表时间：
1997
影响因子：
4.2
通讯作者：
A. Hajek
中科院分区：
文献类型：
--
作者：
A. Hajek
摘要1991 ~ 1996年，在纽约中部对舞毒蛾病原真菌麦麦虫的活动进行了研究。这种真菌于1990年被引入该地区，但在1990-1992年期间也普遍蔓延到整个区域。1991年，舞毒蛾种群在8个混合硬木样地中非常丰富（平均值± SE = 15，295 ± 4373卵块/公顷），舞毒蛾核型多角体病毒（LdNPV）是微生物导致幼虫死亡的最重要原因，到季节结束时，种群已减少到6875 ± 1345卵块/公顷。1991年，E.在8个样地中，有7个样地发现麦蚜幼虫感染，感染率为0-37%，但与1990年E. maimaiga感染水平。在1992年，引起幼虫死亡的主要微生物是大肠杆菌。麦麦加，感染水平范围从64%至98%; LdNPV也存在于所有11个采样点。1992年在低密度区，E.麦麦蛾感染仅在5龄和更晚的龄期急剧增加。在高密度区，6月上旬两个采样日的2龄和3龄幼虫分别有16%和24%被感染。但感染水平再次达到高峰，在晚龄，虽然早在高密度比低密度的网站。在1992年期间，更多的尸体的第4和第5+龄产生休眠孢子在较高的密度比在较低的密度地块，这表明增加了二次传播的分生孢子积极弹射尸体。幼虫活动期间的降雨量因年份而异，1991年春季干旱时，LdNPV为优势病原，而E. 1992年期间，麦麦加风盛行，降雨量接近正常水平。从1993年到1996年，舞毒蛾种群数量一直很低，几乎没有LdNPV感染恢复，E.麦麦蛾感染仅在幼虫密度增加后才增加。
Abstract The activity of the gypsy moth fungal pathogen Entomophaga maimaiga was documented from 1991 to 1996 in central New York. This fungus had been introduced to the area in 1990 but also generally spread throughout the region in 1990–1992. In 1991, gypsy moth populations were abundant in 8 mixed hardwood plots (mean ± SE = 15,295 ± 4373 egg masses/ha), the gypsy moth nuclear polyhedrosis virus (LdNPV) was the most important cause of larval mortality by microorganisms, and by the end of the season, populations had decreased to 6875 ± 1345 egg masses/ha. During 1991, E. maimaiga -infected larvae were found at 7 of 8 plots causing 0–37% infection but this was not associated with 1990 E. maimaiga infection levels. In 1992, the major cause of larval mortality by microorganisms was E. maimaiga, with infection levels ranging from 64 to 98%; LdNPV was also present at all 11 plots sampled. At lower density plots in 1992, E. maimaiga infections only increased dramatically during 5th and later instars. In higher density plots, 16 and 24% of 2nd and 3rd instars per the two early June sample dates were infected by E. maimaiga but infection levels once again peaked during later instars, although earlier in higher than lower density sites. During 1992, more cadavers of 4th and 5th + instars produced resting spores in the higher density plots than in the lower density plots, suggesting increased secondary transmission by conidia actively ejected from cadavers. The amount of rain falling during the periods of time that larvae were active differed by year; LdNPV was the dominant pathogen during the dry 1991 spring, while E. maimaiga flourished during 1992, when rain fell at approximately normal levels. From 1993 to 1996, gypsy moth populations remained low, with almost no LdNPV infections recovered, and E. maimaiga infections increased only after larval densities increased.