Curso de Pós-Graduação em Ciências Veterinárias, Instituto de Veterinária, UFRRJ, RJ, Brazil.
Vet Parasitol. 2012 Dec 21;190(3-4):556-65. doi: 10.1016/j.vetpar.2012.06.028. Epub 2012 Jul 10.
The use of entomopathogenic fungi to control arthropods has been reported worldwide for decades. The aim of the present study was to evaluate the virulence of 30 Metarhizium anisopliae s.l. Brazilian isolates from different geographical regions, hosts or substrates on the larvae of Rhipicephalus (Boophilus) microplus ticks under in vitro conditions to the selection of virulent isolates in order to be further used in biological control programs. The current study confirmed the lethal action of M. anisopliae s.l. isolates on R. (B.) microplus larvae with different mortality levels, usually directly proportional to the conidia concentration. No relationship was found between the origin of the isolate and its virulence potential or between the virulence potential and conidia production. Three isolates (CG 37, CG 384 and IBCB 481) caused a high percentage of larval mortality, reaching LC(50) at 10(6) conidia ml(-1), thus requiring a lower conidia concentration to cause an approximately 100% larval mortality. The results of this study suggest that these three isolates are the most promising for use in programs aimed at microbial control in the field.
几十年来，利用昆虫病原真菌来控制节肢动物已在全球范围内得到报道。本研究的目的是评估来自不同地理区域、宿主或基质的 30 株巴西金龟子绿僵菌复合种对体外条件下微小牛蜱幼虫的毒力，以选择毒力强的分离株，从而进一步用于生物防治计划。本研究证实了金龟子绿僵菌复合种对微小牛蜱幼虫的致死作用，死亡率水平不同，通常与分生孢子浓度直接成正比。分离株的起源与其毒力潜力之间没有关系，也与毒力潜力和分生孢子产生之间没有关系。三个分离株（CG37、CG384 和 IBCB481）导致幼虫死亡率很高，达到 LC50 为 106 个分生孢子 ml-1，因此需要较低的分生孢子浓度才能导致大约 100%的幼虫死亡。本研究结果表明，这三个分离株最有希望用于田间微生物控制计划。
