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Enzyme proteins obtained from seedling plants show distinct patterns (isozymes) after migration in an electric field. Crop varieties differ in isozymes, and these differences open new possibilities for “fingerprinting” varieties for identification purposes.

Flower thrips oviposit in newly developing grape berries and produce a halo spot. The halo spot consists of a small dark scar surrounded by whitish tissue. If too numerous, these halo spots either reduce the grade of table grapes or result in their being culled. Fortunately only a few varieties such as Almeria, Calmeria and Italia are ordinarily affected. The greatest damage potential occurs with Italia since the skin may split at the site of a halo spot during ripening and lead to bunch rot.

Trials conducted in Kern County Thompson Seedless vineyards in 1972 showed that flower thrips nymphs, feeding under persisting caps (calyptras), are associated with the sunburst or starfish scars which have proved troublesome in recent years. The gibberellin sprays used in producing table Thompsons, accentuate this damage.

In the summer of 1968, a small scale insect, the pine needle scale (Chionaspis (Phenacapis) pinifoliae, Fitch), was discovered in high densities within the city limits of South Lake Tahoe. The city lies within natural stands of lodge-pole and Jeffrey pine and both tree species were heavily infested with the scale. The infestation encompassed a total area of some 1300 acres. Investigations of the scale outbreak were initiated by the Division of Biological Control, University of California, Berkeley, the State Division of Forestry, the State Bureau of Vector Control and Solid Waste Management, and Mosquito Control Service Area No. 3.

Globe artichokes are a uniquely Californian vegetable in the U.S., and account for about 4% of world-wide production. The one variety, Green Globe, has been the mainstay of the California industry for many years, but consideration of present and future production needs of California growers (as well as the potential benefits of a broader base of varietal sources) has resulted in initiation of a varietal improvement program. Magnifico, discovered early in this program, has several favorable characteristics indicating potential value as a complemental variety with Green Globe.