Introduction
Cauliflower, Brassica oleracea L. var. botrytis L. is a cole crop belongs to the family Cruciferae. It is one
of the important vegetable crops in the world. It contains most of the minerals and vitamins necessary for human
diet. For growing of cauliflower the problems usually arise during the growing season are some of the insect pests
that cause severe damage to the plant. The major insect pests commonly found attacking cauliflower in almost all
growing areas and in all seasons are ‘diamondback moth’ (DBM) and ‘common cutworm’.
To control these insect pests, most of the growers relied only on the use of insecticides and they applied
on the schedules or calendar spraying without any considerations whether the pests are present in the field or
damage occurs or not. Such practices can create the following problems: (1) selection of resistance in population,
(2) destruction of beneficial species, (3) resurgence of treated populations, (4) outbreak of secondary pests, (5)
residues in foods and environment and (6) hazard to human and environment (Luckmann and Metcalf, 1994).
Sole reliance on insecticides has created problems for controlling insect and maintaining environment.
Thus intensified search for alternative strategies of pest control is necessary. Among the strategies available,
botanical insecticide is one of the promising tactic to control the vegetable pests, for example, the extracts or
products derived from Non-Tai-Yak (Stemona spp).