Seasonal Incidence and Damage Potentiality of Basilepta subcostata (Jacoby) and Bhamoina varipes (Jacoby) (Coleoptera: Chrysomelidae) in Banana Cultivars from Southern part of Bangladesh

Abstract

Experiments on seasonal incidence and damage potentiality of the Basilepta subcostata (Jacoby) and Bhamoina varipes (Jacoby) (Coleoptera: Chrysomelidae) in banana cultivars from Southern part of Bangladesh were carried out in the banana orchard during the period from June, 2021 to July, 2022. Four banana cultivars viz. Sabri, Amrita sagar, Kanthali and kach kala were selected to know the seasonal incidence and damage potentiality of Banana Leaf and Fruit Beetles. They occurred throughout the year but they were more active from May to October though the pick period of activity from June to October and cause severe damage to banana. The highest mean number of beetle population per plant recorded on Amrita sagar (25.2/plant) followed by Sabri (21.4/plant), Kach kala( 13.4/plant) and Kanthali kala (2/plant). Highest damage per sq. inch of leaf was recorded in Amrita sagar (15.6 ± 0.8) in the month of July followed by Sabri (12.8 ± 0.8), Kach kala (9.0 ± 1.0) and Kanthali kala (0.8 ± 0.3). Considering the percent fruit damage per bunch, Banana Leaf and Fruit Beetle was found mostly harmful to Amrita sagar (85.5) followed by Sabri (77.46), Kach kala (36.93) and Kanthali kala (2.46). Among the two species, Basilepta subcostata was recorded highest in number per plant (19.2) in Sabri on September followed by Bhamoina varipes (1.8), and recognized as more potential to damage leaves and fruits of Banana. Bhamoina varipes was found only in two banana cultivars ie. Sabri and Kach kola whereas Basilepta subcostata was found in four cultivars. The incidence of beetle population and scars produced by the beetle was significantly and positively correlated with rainfall, temperature and relative humidity.