Data/hora: 23/06/2024 21:32:18

Biblioteca(s): | Embrapa Meio Ambiente.
Data corrente: | 30/07/2020
Data da última atualização: | 25/08/2021
Autoria: | IWANICKI, N. S.; MASCARIN, G. M.; MORENO, S. G.; EILENBERG, J.; DELALIBERA JUNIOR, I.
Afiliação: | NATASHA SANT'ANNA IWANICKI, ESALQ-USP; GABRIEL MOURA MASCARIN, CNPMA; SARA GIRO MORENO, ESALQ-USP; JORGEN EILENBERG, University of Copenhagen; ITALO DELALIBERA JUNIOR, ESALQ-USP.
Título: | Growth kinetic and nitrogen source optimization for liquid culture fermentation of Metarhizium robertsii blastospores and bioefficacy against the corn leafhopper Dalbulus maidis.
Ano de publicação: | 2020
Fonte/Imprenta: | World Journal of Microbiology and Biotechnology, v. 36, article 71, 2020.
ISSN: | 1573-0972
DOI: | https://doi.org/10.1007/s11274-020-02844-z
Idioma: | Inglês
Conteúdo: | Abstract: The cosmopolitan entomopathogenic and root endophytic fungus Metarhizium robertsii has a versatile lifestyle and during liquid fermentation undergoes a dimorphic transformation from hyphae to conidia or microsclerotia, or from hyphae to blastospores. In all cases, these processes are mediated by environmental and nutritional cues. Blastospores could be used in spray applications to control arthropod pests above ground and may serve as an attractive alternative to the traditional solid-grown aerial conidial spores of Metarhizium spp. found in commercial products. Nitrogen is a vital nutrient in cell metabolism and growth; however, it is the expensive component in liquid cultures of entomopathogenic fungi. Our goals in this study were to optimize nitrogen sources and titers for maximum production of M. robertsii blastospores cultured in shake flasks at highly aerated conditions and to further determine their virulence against the corn leafhopper Dalbulus maidis, an important vector of serious pathogens in maize crops worldwide. Our fermentation studies revealed that the low-cost corn steep liquor (CSL) was the most suitable nitrogen source to improve blastospore growth in M. robertsii.The growth kinetic assays determined the optimal titer of 80 g L-1 and a yield up to 4.7 × 100.000.000 cells mL-1 within 5 days of cultivation (3 days preculture and 2 days culture), at a total cost of US$0.30 L-1. Moreover, the blastospore growth kinetic was strongly dependent on glucose and nitrogen consumptions accompanied by a slight drop in the culture pH. Insect bioassays evidenced a high virulence of these blastospores, either as dried or fresh cells, to D. maidis adults fed on maize plants. Our findings provide insights into the nutritional requirements for optimal and cost-efficient production of M. robertsii blastospores and elucidate the potential of blastospores as an ecofriendly tool against the corn leafhopper.
Palavras-Chave: | Biocontrol; Dimorphic growth; Fungal entomopathogen; Fungal nutrition.
Thesagro: | Fungo Para Controle Biológico; Milho; Praga de Planta; Zea Mays.
Thesaurus Nal: | Biological control agents; Corn; Entomopathogenic fungi; Metarhizium robertsii; Plant pests; Virulence.
Categoria do assunto: | H Saúde e Patologia
Registro original: | Embrapa Meio Ambiente (CNPMA)
Exemplares: | CNPMA - (16791-1) - UPC - AP - DD -  -  -  - DIS