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Like all vegetatively propagated plants, roses are subject to infection by virus and virus-like diseases that spread during propagating operations. Studies by plant pathologists with the California Department of Food and Agriculture have shown a 14 percent loss in salable blooms of virus-diseased greenhouse roses. Similar losses occur in landscape roses. Diseased plants tend to be less vigorous and less likely to survive than healthy plants, and diseases often detract from the aesthetic quality of the plant.

U. C. researchers are surgically transferring embryos in beef cows and heifers to increase the twinning rate and develop management practices for herds with large percentages of twins.

Trials with an in-tree collector-decelerator catch frame have demonstrated the practicability of harvesting fresh-market plums mechanically. Fruit quality was competitive with that obtained by hand harvest and exceeded that from an under-tree catch frame.

There is no evidence that the California Land Conservation Act of 1965 has “conserved” agricultural land.

Reports from other apple producing states have shown that two chemical growth regulators, Alar and ethephon, could have a distinct effect on apple maturity. Alar has been reported to increase firmness of fruit, delay maturity, increase red surface color of red varieties, reduce incidence of scald, and reduce pre-harvest drop. Ethephon has been shown to hasten fruit maturity, improve the soluble solids content of fruit, and improve red surface color of red varieties.

Decreased yellow berry—a disorder of Cocorit durum wheat—was associated with increased protein content, which, in turn, was affected by nitrogen and irrigation applications.

Prospects are good that plant breeders will be able to improve meadowfoam so that it will eventually be grown as an oil-seed crop.

Increasing losses to the navel orange-worm, Paramyelois transitella (Walker), have led to a multi-disciplinary research program to find better methods of controlling this primary pest of almonds in California. One result of this research was the development of a new method for monitoring navel orangeworm (NOW) moth activity. The device used-an “egg trap”—enables growers, field men, and researchers to monitor female moth flights and egg-laying (oviposition) activity directly, rather than monitoring the flight of male moths, as when using sex pheromone traps.

Electronic sorting of cantaloupes into maturity grades in commercial packing sheds appears possible by use of reflected light measured from fruit of different maturities (colors). In recent studies at the University of California, Davis both dry and wet melons were tested. Measurments were made on 10 melons in each of four maturity grades—Partly Slipped, Hard Ripe, Eastern Choice, and Western Choice. Measurments were made with a Beck-man Ratio Recording Spectrophotometer with a reflectance unit attached.

An infestation of the gypsy moth, Lymantria dispar (L.), was discovered in San Jose in October 1976, only a year after positive identification of Dutch elm disease in California. In all respects, the gypsy moth is an even greater threat than Dutch elm disease to California's landscape trees.