The melon fruit fly, Bactrocera cucurbitae: a review of its biology and management.

The melon fruit fly, Bactrocera cucurbitae (Coquillett) (Diptera: Tephritidae) is distributed widely in temperate, tropical, and sub-tropical regions of the world. It has been reported to damage 81 host plants and is a major pest of cucurbitaceous vegetables, particularly the bitter gourd (Momordica charantia), muskmelon (Cucumis melo), snap melon (C. melo var. momordica), and snake gourd (Trichosanthes anguina). The extent of losses vary between 30 to 100%, depending on the cucurbit species and the season. Its abundance increases when the temperatures fall below 32 degrees C, and the relative humidity ranges between 60 to 70%. It prefers to infest young, green, soft-skinned fruits. It inserts the eggs 2 to 4 mm deep in the fruit tissues, and the maggots feed inside the fruit. Pupation occurs in the soil at 0.5 to 15 cm below the soil surface. Keeping in view the importance of the pest and crop, melon fruit fly management could be done using local area management and wide area management. The melon fruit fly can successfully be managed over a local area by bagging fruits, field sanitation, protein baits, cue-lure traps, growing fruit fly-resistant genotypes, augmentation of biocontrol agents, and soft insecticides. The wide area management program involves the coordination of different characteristics of an insect eradication program (including local area options) over an entire area within a defensible perimeter, and subsequently protected against reinvasion by quarantine controls. Although, the sterile insect technique has been successfully used in wide area approaches, this approach needs to use more sophisticated and powerful technologies in eradication programs such as insect transgenesis and geographical information systems, which could be deployed over a wide area. Various other options for the management of fruit fly are also discussed in relation to their bio-efficacy and economics for effective management of this pest.

Dissipation of lindane and fenvalerate residues in chickpea (Cicer arietinum L.) under Indian climatic conditions.

Dissipation behavior of lindane 20 EC (400 and 800 g a.i./ha) and fenvalerate 0.4% dust (75 and 150 g a.i./ha) applied on chickpea (var. H 208) for controlling pod borer under field conditions during rabi 1994-1995 at pod initiation stage was studied. Grains from lower dose of lindane at harvest contained residues below maximum residue limit value (0.25 microg g(-1)), whereas no measurable amount of fenvalerate residues were found in grains of both doses at harvest. A waiting period of 7 days for lindane and 1 day for fenvalerate is suggested from point of hazards due to residues, when applied at recommended dose. The residues calculated from consumption of chickpea (60 g/person/day) is much below the maximum permissible intake of lindane and fenvalerate; hence the recommended doses can be considered safe from point of view of hazards to humans.