Ontogeny and integrated management of Alcidodes porrectirostris Marsha (Coleoptera: Curculionidae) infesting walnut fruits in Manoor Valley (Kaghan), KPK, Pakistan

Alcidodes porrectirostris is first time reported from Pakistan. Adults lay eggs in young green fruits of walnut during first and second week of May. First and second instar larvae feed on the green skin/flesh and the third instar bore through the husk/shell and reach the kernel of the fruit. At this time most of the infested fruits drop to the ground. Larval period lasts for 45 ± 5.2 days. Larvae start pupation inside the fallen fruits by early July and the pupal period last for 14 ± 2.7 days. Adults start emerging while still inside the fruits in the last week of July and early August. Fruit fall due to weevil infestation starts from middle of May and continue to the end of July, most fruits fall during the third week of June. All the developmental stages (larvae, pupae and adults) have been found inside the fallen fruits. Development of the weevil has been delayed by two weeks at higher elevations (8000 ft). A species of ants was observed feeding on larvae and pupae of the weevil. A bacterial infection has killed 20% larvae and 5% pupae. A fungus was also found infesting adult weevils. Integrated management would include collection and disposal of the fallen fruits by burying them under 2 feet of compact soil, and conservation of the biocontrol agents found in the valley.