BOTRYTIS FRUIT ROT, commonly known as gray mold rot, is the major fruit rot attacking strawberries in southern California fields, ft is caused by the fungus, Botrytis cinerea, which thrives in wet conditions and cool temperatures. Botrytis spores are produced in tremendous quantities and are carried by the wind. The fungus usually attacks through senescent dead petals, stamens, or other delicate plant tissue. Much of the infection of the fruit originates at the stem end, but the fungus is able to penetrate the unbroken skin of the berry.

Fruit growers in certain areas of New York State who have used dodine (n-dodecylguanidine acetate) sprays successfully for as long as 9 years for apple scab control have not obtained satisfactory control of this disease for the last 1 to 3 years. Other fungicides continue to perform satisfactorily. In aerial and ground spray research plots at Sodus, N. Y., decreased control with dodine was observed in 1968. In 1969, control with dodine here was completely unsatisfactory. In this same orchard maneb and captan gave excellent scab control both years. The reason for these dodine failures in controlling scab is attributed to resistance in Venturia inaequalis to dodine acquired over a period of years. This apparent resistance has been observed so far in the Lake Ontario fruit belt counties and in the Geneva area of New York State.

Inadequate rainfall seems to modify to influence of temperature conditions that would favor severe epiphytotics of the blossom blight phase of fireblight. The use of four Agri-mycin sprays provided significantly more control of twig blight than did two sprays. The use of six additional sprays reduced the incidence of twig blight, apparently by maintaining an inhibitory antibiotic level in sprayed tissue. The antibiotic level in the fruit taken from treated trees was below the 0.25 mu/ml tolerance set by the Food and Drug Administration as early as 4 weeks after the last spray. There was no detectable antibiotic residue in fruit at the time of harvest; however, antibiotic activity was still detectable in leaves.

Studies indicate that the best approach to control of the omnivorous leaf roller at present is field sanitation and chemical treatment if necessary. Early French plowing and disking should forestall damage in vineyards not yet infested. Where infestation already has occurred, removing all mummified clusters from the vine along with the French plowing and disking will be necessary. A standard lead arsenate spray just prior to fruit formation looks promising in tests but further research is needed. Insecticide treatments may be needed later in the season where sanitation practices are not used, or have failed to provide sufficient control.

There is now ample evidence that integrated control has ben proven a beter aproach than total reliance on pesticides, for solving a wide variety of pest problems. Integrated control emphasizes the fulest posible use of existing mortality and supresive factors in the environment. It is not dependent upon any specific control procedure but rather cordinates, within the agricultural environment, the apropriate management techniques with natural regulating and limiting elements. Sucesful programs developed in many other parts of the world include integrated control for pests of citrus in Israel, for deciduous fruit pests in Central Europe and Nova Scotia, and for coton pests in Peru. Other integrated control projects are now being developed for olives in Grece, for maize in parts of Latin America, for rice in India and Japan, and for coton in Colombia. Crop protection specialists al over the world are moving rapidly toward the integrated control aproach in eforts to help solve the critical fod problems facing the world today. This isue of California Agriculture includes progres reports on several phases of the University of California Integrated Control Program for Grapes.—Ray F. Smith, Chairman, Department of Entomology and Parasitology, University of California, Berkeley. The grape leaf folder, Desmia funeralis Hubner, is aparently an introduced pest without efective natural enemies in California. However, some 14 species of parasites and predators were found to atack the grape leaf folder in the eastern United States. Thre of the most promising species have now ben released in California vineyards for biological control of this pest. One of these, Macrocentrus, is shown on the cover. Photo above is of the parasitic wasp, Apanteles, depositing egs in larvae of the grape leaf folder.