Location: Crop Bioprotection ResearchTitle: Nitrogen source affects productivity, desiccation tolerance, and storage stability of Beauveria bassiana blastospores
|MASCARIN, GABRIEL - Embrapa|
|KOBORI, NILCE - Iharabras Sa Industrias Quimicas(IHARA)|
|DELALIBERA, ITALO - Universidade De Sao Paulo|
Submitted to: Journal of Applied Microbiology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 1/4/2018
Publication Date: 3/1/2018
Citation: Mascarin, G.M., Kobori, N.N., Jackson, M.A., Dunlap, C.A., Delalibera, I. 2018. Nitrogen source affects productivity, desiccation tolerance, and storage stability of Beauveria bassiana blastospores. Journal of Applied Microbiology. 124:810-820. doi: 10.1111/jam.13694.
Interpretive Summary: This study investigate the effects of different nitrogen sources for the large scale production of an important species of insect killing fungi. This study identifies low cost nitrogen sources that improve the yield and storage stability of this biopesticide. Improving the economics of biopesticides hastens the adoption of these crop protection solutions and creates more sustainable agricultural practices. This research benefits U.S. farmers and consumers that rely on crops impacted by insect pests.
Technical Abstract: Aims: Nitrogen is a critical element in industrial fermentation media. This study investigated the influence of various nitrogen sources on blastospore production, tolerance to anhydrobiosis stress, and storage stability using two strains of the cosmopolitan insect pathogenic fungus Beauveria bassiana. Methods and Results: Complex organic sources of nitrogen such as soy flour, autolyzed yeast and cottonseed flour induced great numbers of blastospores within 2–3 day fermentation, which also survived drying and remained viable (32–56% survival) after 9 month storage at 4 °C, although variations were found between strains. Nitrogen availability in the form of free amino acids directly influenced blastospore production and resistance to anhydrobiosis. Increasing glucose and nitrogen concentrations up to 120 g L**-1 and 30 g L**-1, respectively, did not improve blastospore production but enhanced desiccation tolerance. Cell viability after drying and upon fast-rehydration was increased when = 25 g acid hydrolyzed casein L**-1 was supplemented in the liquid culture medium. Conclusions: These findings indicate that low-cost complex nitrogen compounds are suitable to enhance yeast-like growth by B. bassiana with good desiccation tolerance and therefore support its further scale-up production as a mycoinsecticide. Significance and Impact of Study: Nitrogen is the most expensive nutrient in liquid media composition, but this study underscores the feasibility of using low-cost nitrogen compounds composed mainly of agro-industrial by-products for rapid production of stable, active B. bassiana blastospores by liquid culture fermentation.