Tarnished Plant Bug - Lygus lineolaris (Palisot de Beauois)

Dr. Randy Hudson, Extension Entomologist, The University of Georgia, Department of Entomology, Tifton, GA 31793
Dr. David Adams, Extension Entomologist, The University of Georgia, Department of Entomology, Tifton, GA 31793

Order Heteroptera: Family Miridae

Description: The tarnished plant bug adult is a brownish-yellow mottled insect of approximately 3-6 mm in length. It is oval in shape with a distinctive white triangle located just behind the "shoulders". Nymphs are yellow-green in color and have 4 distinctive black dots on the back. First and second instar nymphs will appear to have very long legs and antennae. Wing pads are present at the fourth instar. Hosts: Cotton, vegetables, fruits, clovers, canola, and over 50 other crops, as well as most spring and late summer weeds. Damage: Tarnished plant bugs feed by piercing the plant with very small mouthparts and sucking out the plant juices. The damage is most inconspicuous and is not evident to the eye. Damaged plant tissue will often wilt and may abort. In cotton, damaged pinhead squares may show a slight discoloration of the infected anthers. In fruits and vegetables, damage may appear as indented or cat-faced injury. Tarnished plant bud injury is often associated with poor seed germination. This is especially important in seed production systems like cotton, alfalfa, clover and canola.

Tarnished plant bug life cycle Photo by : UGA Archives

Tarnished plant bug feeding damage of cotton boll Photo by: Barry Freeman, Auburn University

Life Cycle: Tarnished plant bugs remain active in all life stages throughout the year. Tarnished plant bugs will primarily overwinter as adults. In late spring, adults will migrate to food sources to mate and reproduce. First spring generations develop on annual winter weeds, small grains, canola, and wild grasses. As weeds and winter crops mature, plant bugs will migrate into other host crops including cotton. During the summer, the life cycle from egg to adult takes approximately 4 weeks.

Control: Treat for tarnished plant bug in small seeded crops when plant bugs are numerous and visible damage is present. Treat for tarnished plant bugs in cotton when plant bugs are present and the plant is not retaining 85% of the young pinhead squares.

In: Roberts, P. M. and G. K. Douce, Coordinators. 1999. Sucking Insects. A County Agent's Guide to Insects Important to Agriculture in Georgia. Univ. of GA, Col. Ag. Env. Sci., Coop. Ext. Serv., Tifton, GA USA. Winter School Top Fifty Agricultural Insect Pests and Their Damage Sessions, Rock Eagle 4-H Ctr., Jan. 20, 1999

Selected References and Suggested Readings