Location: Crop Bioprotection ResearchTitle: Soil application of formulated Metarhizium brunneum F52 (Hypocreales: Clavicipitaceae) containing microsclerotia controls eggs of Aedes aegypti (Diptera: Culicidae) Author
|Strickman, Daniel - Gates Foundation|
|Rooney, Alejandro - Alex|
Submitted to: Meeting Abstract
Publication Type: Abstract Only
Publication Acceptance Date: 7/25/2017
Publication Date: 11/5/2017
Citation: Weiler, L., Behle, R.W., Johnson, E.T., Strickman, D.A., Rooney, A.P. 2017. Soil application of formulated Metarhizium brunneum F52 (Hypocreales: Clavicipitaceae) containing microsclerotia controls eggs of Aedes aegypti (Diptera: Culicidae). Meeting Abstract.
Technical Abstract: We evaluated the potential of a granular formulation of Metarhizium brunneum F52 containing microsclerotia (MbMSc granules) for control of Aedes aegypti (L.) by targeting eggs. MbMSc granules produced infective conidia within 14 days after application to moist potting soil, producing 5.9 × 10**5, 2.08 × 10**6 and 6.85 × 10**6 conidia from 1 mg, 5 mg and 25 mg MbMSc granules, respectively. Application of MbMSc triggered premature eclosion of eggs with mean percent eclosion of 39% and 49% of the eggs treated with 5 and 10 mg MbMSc granules, respectively, when exposed for 14 days on moist filter paper. Premature eclosion of eggs started at 3 days subsequent to MbMSc granule application and survival of larvae was significantly reduced for granule treated eggs (43 ± 2.3% and 33 ± 3.2% larvae survived for 5 mg and 10 mg granule treatments, respectively) when compared with untreated eggs (92 ± 1.4% larval survival). When MbMSc granules were applied in moist potting soil with mosquito eggs, rates of 5 mg and 25 mg of MbMSc granules significantly reduced adult emergence to only 45 ± 1.7% and 35 ± 2.2% emergence, respectively. Eggs treated with increasing concentrations of fungal conidia enhanced premature eclosion of eggs. Treatment with Mb F52 increased protease activity in infected eggs as evidenced by zymographic assays. Our results demonstrate that MbMSc granules are a promising candidate for control of Ae. aegypti and that fermentative production of Mb F52 microsclerotia as the active propagule has potential for use for mosquito control.