Local host fruiting pattern and climate variations impact on fruit fly (Bactrocera dorsalis) population trends: A regional fruit fly population tracker for management options

Abstract

Oriental fruit flies, Bactrocera dorsalis being highly polyphagous, mobile and relatively long lived (~3 months), the efficacy of area-wide management programs is mainly influenced by field fruit fly population levels. A study was conducted to understand the seasonal abundance and host shift pattern of B. dorsalis, a major pest of mango, Mangifera indica L. in relation to climatic factors and host fruit availability as it is known to survive on both wild and cultivated fruits. The fruit fly population attained high levels in the months of March-July due to the availability of main host(mango) as well as supporting host fruits (guava, sapota, rose apple, wild fig, singapore cherry, sour cherry, karonda, star fruit) and the population was less during November- January. Correlation analysis showed that the fruit fly trap catch was significantly negatively correlated with relative humidity (r =-0.87, RH I; r = -0.63, RH II), whereas it was significantly positively correlated with maximum temperature (r = 0.89), host fruit availability (r = 0.89) and fallen fruits (r = 0.80). The statistically significant values (P =0.01, 0.05) revealed that the occurrence of pest incidence is mainly due to its host availability and prevailing climatic factors. Therefore, the management of fruit fly B. dorsalishas to be promoted from the month of February onwards to realize maximum benefit of management strategies.