Pests of Walnut

Many species are considered as pests in walnut production such as insects and mites, diseases, weeds and vertebrate pests. Among them, insects and mites are key pests of walnut and cause considerable damage. The knowledge of biology and nature of damage helps in the management of target insect pests at appropriate time, which reduces pesticidal applications and least effects on natural enemies in the field to maintain the pest populations in equilibrium position. Some insect pests, like aphids and chafer beetle, infest the nursery and cause serious damage. In the field, stem borer infesting tree trunk, shot hole borer infesting branches, gypsy moth and tortrix moth defoliating the leaves, blister mite puckering or blistering the leaves and husk fly damaging the husk all affect the quality and market value of the fruit. In storage, some insect pests, viz. Indian meal moth and sawtooth beetles, cause damage to the walnut. IPM is an ecofriendly based strategy that relies heavily on long-term prevention of pests and their damage through different techniques.