A field collected population of T. tabaci was maintained in a laboratory rearing . Rearing units consisted of a glass jar (0.5 l) that was covered by a fine mesh cloth (105 mm) for ventilation. A piece of filter paper was placed on the bottom of each glass jar as a hiding place and pupation site for prepupae and pupae.The insects were provided with fresh leek leaf pieces (Allium porrum L.) for feeding and oviposition three times a week.