Development of novel spray-dried and air-dried formulations of Metarhizium robertsii blastospores and their virulence against Dalbulus maidis

Autor(es)

Iwanicki, Natasha Sant'Anna ^[1] ; Mascarin, Gabriel Moura ^[2] ; Moreno, Sara Giro ^[1] ; Eilenberg, Jorgen ^[3] ; Delalibera, Jr., Italo ^[1]

Afiliação do(s) autor(es)

^[1] Univ Sao Paulo ESALQ USP, Dept Entomol & Acarol, Escola Super Agricultura Luiz de Queiroz, Av Padua Dias 11, CP 9, BR-13418900 Piracicaba, SP - Brazil

^[2] Brazilian Agr Res Corp, Lab Environm Microbiol, Embrapa Environm, Rodovia SP 340, Km 127-5, BR-13918110 Jaguariuna - Brazil

^[3] Univ Copenhagen, Dept Plant & Environm Sci, Thorvaldsensvej 40, DK-1871 Frederiksberg - Denmark

• Tipo de documento: Artigo Científico
• Fonte: Applied Microbiology and Biotechnology; v. 105, n. 20 SEP 2021.
• Citações Web of Science: 0

Resumo

The present research addressed spray-drying and air-drying techniques applied to Metarhizium robertsii blastospores to develop wettable powder (WP) formulations. We investigated the effect of co-formulants on blastospore viability during drying and assessed the wettability and stability of formulations in water. The effect of oxygen-moisture absorbers was studied on the shelf life of these formulations stored at 26 degrees C and 4 degrees C for up to 90 days. Additionally, we determined the virulence of the best spray-dried and air-dried formulations against the corn leafhopper Dalbulus maidis. While sucrose and skim milk played an essential role as osmoprotectants in preserving air-dried blastospores, maltodextrin, skim milk, and bentonite were crucial to attain high cell survival during spray drying. The lowest wettability time was achieved with spray-dried formulations containing less Ca-lignin, while charcoal powder amount was positively associated with formulation stability. The addition of oxygen-moisture absorbers inside sealed packages increased from threefold to fourfold the half-life times of air-dried and spray-dried formulations at both storage temperatures. However, the half-life times of all blastospore-based formulations were shorter than 3 months regardless of temperature and packaging system. Spray-dried and air-dried WP formulations were as virulent as fresh blastopores against D. maydis adults sprayed with 5 x 10(7) blastospores mL(-1) that induced 87.8% and 70.6% mortality, respectively. These findings bring innovative advancement for M. robertsii blastospore formulation through spray-drying and underpin the importance of adding protective matrices coupled to oxygen-moisture absorbers to extend cell viability during either cold or non-refrigerated storage. Graphic abstract (AU)

• Processo FAPESP: 16/20610-6 - AVANÇOS NA PRODUÇÃO E FORMULAÇÃO DE BLASTOSPOROS DE Metarhizium E TRANSCRIPTOMA DA FASE DE CRESCIMENTO LEVIDURIFORME
• Beneficiário: Natasha Sant Anna Iwanicki
• Modalidade de apoio: Bolsas no Brasil - Doutorado