Abstract
The effect of ultraviolet radiation on entomopathogenic fungi can be very prejudicial for causing damage to the conidia. Formulations can help protecting these fungal structures against radiation. The objective of this study was to evaluate the effect of UV radiation on pure and encapsulated conidia Beauveria bassiana and Metarhizium anisopliae sensu lato, and to evaluate their pathogenicity on the sugarcane borer, Diatraea saccharalis. The pure conidia and the sodium alginate capsules containing the fungi were submitted to the ultraviolet radiation in different temperatures and exposure times. On the pure conidia, the radiation had a deleterious effect after 5 minutes of exposure, going from 94% to 52% germination for B. bassiana and from 96% to 54% for M. anisopliae. The alginate formulation protected the B. bassiana conidia against the radiation in all times they were evaluated (15 minutes to 48 hours), because, even after exposure, the fungi remained viable. The dry encapsulated conidia B. bassiana caused 79.6% mortality of the studied pest and the M. anisopliae caused only 10%.
Highlights
Entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae have pathogenic action on various agricultural insect pests [1]-[9]
This study aimed to evaluate the effect of ultraviolet radiation on conidia of the formulated and unformulated entomopathogenic fungi B. bassiana and M. anisopliae, in order to verify the pathogenicity of both fungi on the insect Diatraea saccharalis
With the 4 lamps switched on, for the fungus B. bassiana, in 5 minutes of exposure to radiation, germination reached 52% compared to 94% in the control, at 10 minutes this index fell to 11% and at 15 minutes it fell to 1.0% (Table 1)
Summary
Entomopathogenic fungi Beauveria bassiana and Metarhizium anisopliae have pathogenic action on various agricultural insect pests [1]-[9]. Among the advantages of the agricultural use of microbial products (bio pesticides), it is possible to underscore specificity and selectivity, low probability of target insects building up resistance, longer-lasting pest control, low toxicity to the environment and applicator, lower cost of development and registration, etc. Temperature is important for entomopathogenic fungi because it affects their metabolism by altering processes for the production of enzymes, toxins, spore germination, development of the germinative tube, penetration, colonization and reproduction. Radiation can affect conidia germination and the early stages of development of the germinative tube [12]. According to Bell [13], the fungus B. bassiana loses its infection ability when subjected to direct sunlight for three hours
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
