Brown County AgriLife Extension Agent Scott Anderson is getting numerous phone calls now concerning Aphid problems. Aphids, also called plant lice, are a diverse group. There are over 250 species in the super family Aphidoidea. They are small, from 1/16 to 1/8 inch long. They are soft bodied, pear shaped and vary in color and body markings. They may be winged or wingless. The body is segmented. Their mouth parts are modified for sucking plant juices. On the back of the 5th abdominal segment, a pair of tube-like structures called cornicles is present on most species. Most Aphids reproduce sexually and develop through gradual metamorphosis but also through parthenogenesis during which the production of off spring occurs without mating. The average life span of an adult is approximately 1 month with sexual maturity reached in 4-10 days. Aphids reproduce faster than most other insects. It is noted that under greenhouse conditions some Aphids may complete nearly 50 generations with each adult producing around 80 young.
Aphids draw sap from plant phloem tissue using mouth parts modified for piercing and sucking. Some Aphids feed on foliage while others feed on twigs, branches, fruits, flowers or roots of plants. Some species inject toxic salivary secretions into plants during feeding. Many Aphids secrete a sticky substance called honeydew. If left unchecked, Aphids can stunt plant growth, deform and discolor leaves and fruit or cause galls to form on leaves, stems, and roots. As Aphid populations develop, infestation sites become littered with cast skins, especially on the underside of vegetable plant leaves. Aphids are important vectors of plant diseases. Aphid populations are often moderated by environmental stresses (high winds, heavy rains and natural enemies such as lady beetles).
Some “organic” options for use in suppressing Aphid numbers in vegetable gardens include:
Axadirachtin Neem Oil
Pyrethrum Horticultural Oil
Other chemical options include:
Sevin Pyrethrum
Bifenthrin
As always, read and follow labels and be cautious of what you treat your vegetables with. If a product is not labeled for a particular vegetable plant, do not use it.