Back to Search
Start Over
Development of novel spray-dried and air-dried formulations of Metarhizium robertsii blastospores and their virulence against Dalbulus maidis.
- Source :
- Applied Microbiology & Biotechnology; Oct2021, Vol. 105 Issue 20, p7913-7933, 21p
- Publication Year :
- 2021
-
Abstract
- 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 °C and 4 °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 × 10<superscript>7</superscript> blastospores mL<superscript>−1</superscript> 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. Key points: • Cost-effective wettable powder formulations of M. robertsii blastospores were developed. • Bioefficacy of formulations against the corn leafhopper was comparable to fresh blastospores. • Cold storage and dual oxygen-moisture absorber are critical for extended shelf life. [ABSTRACT FROM AUTHOR]
- Subjects :
- MALTODEXTRIN
METARHIZIUM
CELL survival
SPRAY drying
SKIM milk
COLD storage
Subjects
Details
- Language :
- English
- ISSN :
- 01757598
- Volume :
- 105
- Issue :
- 20
- Database :
- Complementary Index
- Journal :
- Applied Microbiology & Biotechnology
- Publication Type :
- Academic Journal
- Accession number :
- 152928250
- Full Text :
- https://doi.org/10.1007/s00253-021-11576-5