Repellent activity of Salix alba bark extract and Guava oil-based Formulation against Fruit Fly, Bactrocera dorsalis (Diptera: Tephritidae) to protect Guava from infestation under laboratory and semi-field conditions.

Abstract

Abstract Bactrocera dorsalis (DIPTERA: TEPHRITIDAE), the primary pest of guava (Psidium guajava), damages numerous horticulture fruits in tropical and subtropical regions. Use of insecticides adversely affects agro-ecosystem and has environmental consequences. The repellent activity of Salix alba (Willow) bark extract and a Guava oil-based formulation was investigated to protect guava fruit from infestation by the Fruit Fly, B. dorsalis. In laboratory and semi-field experiments, the efficacy of these natural repellents was assessed. B. dorsalis significantly deterred guava fruit treated with S. alba formulation as compared to the extract alone, which exhibited significant anti-feeding activity, and caused a decline in fecundity rate by 60% and larval mortality rate by 90%. When females were allowed to oviposit on guava fruits in laboratory and field after mating, these flies preferred fruits for oviposition that were not sprayed with S. alba-guava oil formulation. GC-MS analysis showed esters and terpenes as the main components for exhibiting repellent property in S. alba-based formulation. Hence, guava oil formulation of S. alba showed a complete protection of guava fruits against B. dorsalis in the laboratory and semi-field conditions to control infestation by B. dorsalis. Further research and field trials are warranted to optimize the application methods and assess the long-term effects on crop yield and overall fruit quality.