ABSTRACTS

MOORE, W.S., J.C. PROFITA, and C.S. KOEHLER. 1979. Soaps for home landscape insect control. California Agriculture 33(6): 13-15.

The utility of soap sprays for insect control was demonstrated as early as 1842. Today there is renewed interest in soap sprays, yet directions for use are often vague and confusing, and the literature is unclear as to how effective soaps are. In a total of eight experiments conducted during 1978, the soap and detergent sprays produced high mortality of all arthropods tested except spittlebugs. The mites, aphids, psyllids, and thrips used in these experiments are all soft-bodied, sucking arthropods, the kind known to be particularly susceptible to soap sprays. The effects of soap and detergent sprays on beneficial insects have not been adequately studied. Because these sprays do not have the residual properties of synthetic organic insecticides, and do not provide the same consistently high level of control, repeat applications of thoroughly applied sprays are indicated. In addition, phytotoxicity may reduce their applicability on certain plants.

LARSON, M.M. 1979. Hormonal control of tree seedling root regeneration. Ohio Report 64(2): 30-31.

When a tree is planted in the soil, two critical events must occur if the tree is to survive and grow. One event is breaking of buds that signals the start of shoot growth. The other event is root regeneration, the formation of new roots on planted trees to replace roots lost or damaged during lifting, storage, and planting operations. The new roots may appear before, during, or after bud break. Delay in root regeneration until after leaf expansion can result in a severe deficiency of water followed by stem dieback or death of the tree. Reseachers have known for some time that the physiological processes of root regeneration are mediated by certain plant hormones, and that these hormones are present at sites where new roots develop. Treatment of nursery stock with hormones to increase early establishment appears possible. The OARDC results suggest that roots treated with solutions containing both auxins and cytokinins may develop numerous new roots that are also vigorous. Field tests of various hormone mixtures are currently underway.