Vázquez-Martínez María Guadalupe, Cirerol-Cruz Blanca Elva, Torres-Estrada José Luis, López Mario Henry Rodríguez
Centro Regional de Investigación en Salud Pública, Instituto Nacional de Salud Pública, Tapachula, Chiapas, México.
Centro de Investigación sobre Enfermedades Infecciosas, Instituto Nacional de Salud Pública, Cuernavaca, Morelos, México.
Rev Soc Bras Med Trop. 2014 Nov-Dec;47(6):716-22. doi: 10.1590/0037-8682-0193-2014.
The use of entomopathogenic fungi to control disease vectors has become relevant because traditional chemical control methods have caused damage to the environment and led to the development of resistance among vectors. Thus, this study assessed the pathogenicity of entomopathogenic fungi in Triatoma dimidiata.
Preparations of 108 conidia/ml of Gliocladium virens, Talaromyces flavus, Beauveria bassiana and Metarhizium anisopliae were applied topically on T. dimidiata nymphs and adults. Controls were treated with the 0.0001% Tween-80 vehicle. Mortality was evaluated and recorded daily for 30 days. The concentration required to kill 50% of T. dimidiata (LC50) was then calculated for the most pathogenic isolate.
Pathogenicity in adults was similar among B. bassiana, G. virens and T. flavus (p>0.05) and differed from that in triatomine nymphs (p=0.009). The most entomopathogenic strains in adult triatomines were B. bassiana and G. virens, which both caused 100% mortality. In nymphs, the most entomopathogenic strain was B. bassiana, followed by G. virens. The native strain with the highest pathogenicity was G. virens, for which the LC50 for T. dimidiata nymphs was 1.98 x108 conidia/ml at 13 days after inoculation.
Beauveria bassiana and G. virens showed entomopathogenic potential in T. dimidiata nymphs and adults. However, the native G. virens strain presents a higher probability of success in the field, and G. virens should thus be considered a potential candidate for the biological control of triatomine Chagas disease vectors.
由于传统化学防治方法对环境造成破坏并导致病媒产生抗药性，利用昆虫病原真菌控制疾病传播媒介已变得至关重要。因此，本研究评估了昆虫病原真菌对二色锥蝽的致病性。
将绿色木霉、黄曲霉、球孢白僵菌和金龟子绿僵菌的孢子悬液（浓度为108个孢子/ml）局部涂抹于二色锥蝽若虫和成虫身上。对照组用0.0001%吐温-80载体处理。连续30天每天评估并记录死亡率。然后计算对50%二色锥蝽致死所需的浓度（LC50），以确定最具致病性的菌株。
球孢白僵菌、绿色木霉和黄曲霉对成虫的致病性相似（p>0.05），与锥蝽若虫的致病性不同（p=0.009）。对成年锥蝽致病性最强的菌株是球孢白僵菌和绿色木霉，二者均导致100%死亡率。在若虫中，致病性最强的菌株是球孢白僵菌，其次是绿色木霉。致病性最高的本地菌株是绿色木霉，接种后13天，其二色锥蝽若虫的LC50为1.98×108个孢子/ml。
球孢白僵菌和绿色木霉对二色锥蝽若虫和成虫均显示出昆虫病原潜力。然而，本地绿色木霉菌株在田间成功的可能性更高，因此绿色木霉应被视为锥蝽查加斯病传播媒介生物防治的潜在候选菌株。
