Pea Pod Borer
· Bean · Gram · Pigeonpea · Chickpea · Soybean · Peanut · ·
Larvae attack the pods of cultivated legumes including garden pea, pigeon pea, common bean and soybean. Soybean is the preferred host. Small larvae feed on the new blossom and the young pods from the inside, occasionally causing them to fall. Injury to pods is characterized by the presence of entry or exit holes where the larva has damaged the seed vessel. Usually one or two larvae can be found in each pod and the build-up of frass causes soft, brown, rotten patches on the surface. Seeds are either partially or entirely eaten, and if flowers and pods are not available, the larvae will feed on foliage.
The damage is caused by the larvae of the moth Etiella zinckenella, a pest with worldwide distribution. Adult moths are nocturnal and have a light brown body with a bulging head and two long protuberant antennae. Forewings are brown-grayish with a characteristic glittering aspect and a white stripe that runs along the fore edge. A golden-orange band crosses the wing on both sides, thereby the common name "gold-banded Etiella moth". Hindwings are light gray, with dark venation and dark, long fringe. Females lay their eggs on blossom or on green fruits and larvae live inside the fruit, eating away the seeds, and easily passing from one bean to another. They are pale green to green with a brownish tinge and and orange head crowned with a black V shape and four black dots. Larva fall to the soil and overwinters within a cocoon in soil at a depth of 2-5 cm and emerge as adults in spring.
Predators include some vertebrates, arthropods and birds. Parasite or parasitoids wasps of the species Bracon platynotae, Perisierola cellularis, and Zatropis tortricidis attack the larvae of the gold-banded Etiella moth, and can have a pronounced effect on its population. Fungal and bacterial diseases can also be used to control the spread of the pest.
Always consider an integrated approach with preventive measures together with biological treatments if available. This moth is usually not considered a major pest of legumes and often do not deserve any course of action. However, insecticides formulations based on endosulfan or monocrotophos have been used as foliar sprays.