Pea thrips

Pea thrips (Kakothrips robustus) is a significant agricultural pest belonging to the order Thysanoptera and the family Thripidae. It is widely recognized as a serious threat to leguminous crops, particularly peas, causing severe damage to flowers and pods during the reproductive stages of plant growth.

Adult insects are small, typically measuring 1.5 to 2 mm in length, and possess dark-brown or black bodies with fringed wings. The larvae are distinguished by their bright yellow or orange coloration. They reside primarily in protected environments such as buds, folded leaves, and inside the flowers of host plants.

The life cycle begins with overwintering as second-instar larvae in the soil. As temperatures rise in late spring, they pupate within soil chambers, emerging as adults to infest emerging crops. The females insert eggs into plant tissues, and the entire cycle can be completed in a few weeks under favorable weather conditions.

Damage occurs when both larvae and adults feed on plant sap. This feeding behavior causes significant physiological stress, leading to flower abortion, stunted pod development, and visible silvery streaks on the surface of pods. Infested crops often show reduced yield quantity and poor grain quality due to the loss of nutrients.

Management strategies focus on reducing populations through both cultural and chemical means. Recommended practices include deep plowing after harvest to disrupt soil habitats, crop rotation, and the selection of early-maturing cultivars. If population thresholds are exceeded, targeted applications of systemic insecticides during the early blooming stage are necessary to maintain crop health.