The vegetable leafminers (Agromyzidae: Diptera) are important economic pests of agricultural crops and ornamental plants in many countries around the world. They are small (2-6mm) insects whose larvae feed entirely in living plant tissues, primarily as leafminers, but also in stems, roots and seeds. The mining larvae feed actually more on sap than on solid tissues of the leaf. The mined leaves turn pale, get distorted and may dry up.  The larval feeding can severely reduce yield and kill the plants at high fly density. Consequently, almost 100 percent of damage to the affected plant.  The Agromyzidae is divided into two subfamilies which have been largely supported by recent analyses both of morphological characters and of DNA sequence data. The Agromyzidae is one of the largest dipteran families, with more than 3000 species belonging to 30 genera worldwide. The species of vegetable leafminers are distributed throughout the world from the north of Greenland to Patagonia and the subantarctic islands south of New Zealand.
Image: Leaf miner

Almost 140 plant families such as Cucurbitaceae, Leguminosae, Solanaceae, Brassiceae, Asteraceae, Compositae is attacked by Agromyzid flies. Over 150 species of cultivated plants of these families are damaged by these pests throughout the world.

The management of agromyzid leafminers continue to be a topic of extensive reset rich and scientific debate. Synthetic and natural insecticides for leafminers control have been extensively researched and are commonly used by farmers and producers regardless of production scale and crops. The effectiveness of these insecticides have been reduced by their indiscriminate use, which has adversely impacted natural enemies and resulted in the development of resistance to several groups of insecticides. Discriminate use of chemicals has to lead to problems like pest resurgence, pest outbreak, and development of resistance by pest species to insecticides, elimination of natural enemies, and risks to human and animal health besides environmental pollution.
                           Image: Vegetable leafminer Liriomyza sativae

Integrated pest management (IPM) seeks to provide an effective and economical control strategy that minimizes the disturbance of anthropogenic control measures on the natural components of the agro-ecosystems. As a result, biological control is often emphasized as an important remediation strategy to combat pest outbreaks. A total of 163 agromyzids and 98 parasitic wasps were reared from the Canberra region from plant samples with agromyzid mines, larva and pupae.

In Bangladesh, around 7 species of agromyzid flies were so far recorded from 53 host plants.
 A sound taxonomic framework is needed in order to determine, what information would be most helpful in the selection and the use of suitable species of parasitoids for use of biological control.

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