Calag Archive

When California rice growers established objectives for the research they have helped support for seven years, they expressed need for varieties with short stature for greater lodging resistance, early maturity (to facilitate harvest before fall rains), and glabrous or smooth hulls to reduce dust during harvesting and drying. We have taken a series of steps toward incorporating these features into Calrosc, a high yielding variety with good cold tolerance and good milling and cooking qualities. Advantages of this procedure are that new desirable features are added step-by-step with minimal danger of losing past achievements.

Powdery mildew of sugarbeet, caused by Erysiphe polygoni, was first found in California in 1934, but did not become prevalent statewide until the 1974 season. Results of trials in 1974 indicated sulfur dust (40 pounds per acre) or wettable sulfur provided excellent control of sugarbeet powdery mildew. ‘Trials were initiated in 1975 to compare 20 pounds of sulfur dust per acre, wet-table sulfur, Benlate + oil, and various other combinations.

When the growth regulator ethephon is applied to walnuts at maturity and when packing tissue between kernel halves turns brown, hull dehiscence and nut loosening are advanced. Harvest can generally begin 7 to 10 days following treatment, which may be 1 to 3 weeks before normal harvest. The possible advantages of an earlier harvest are: improved kernel quality, less insect infestation , greater nut removal, greater hullability, and a more efficient harvest. In the course of University of California experiments and subsequent grower use of ethephon, reports have appeared claiming both longer and shorter nut drying times. The purpose of our investigation was to measure nut drying time after ethephon treatment.

Stock grazing on pastures in which Phalaris species are the predominant grass have on occasion developed what appears to be a neurological disorder which results in the “staggers,” a term used to describe their unsteady, stumbling gait. Other manifestations include restlessness, hyperexcitability, twitching of the ears, head bobbing, jaw tremors, heavy breathing, and an excessively high pulse rate. When driven, the animals are often unable to unflex their forelimbs and they collapse. The pathological features associated with the disorder have not been well defined, although some degeneration of tracts in the spinal cord and haemosiderosis of the kidney have often been observed. Heavy losses of animals have occurred.

Calfornia's coast, from Salinas to San Diego-one of the few areas in the United States that produces celery throughout the year-is now threatened with a soil-borne disease. To date, it has been observed in Orange, Ventura, and San Luis Obispo counties.

For several years cotton growers in southern California have applied broad-spectrum insecticides on a regularly timed basis to control the pink bollworm, Pectinophora gossypiella (Saunders), from June through September. This preventative approach was necessary because growers lacked efficient methods for determining the abundance and activity of pink bollworm moths. Although this regime has provided effective control, repeated applications of insecticide have not only increased production costs, but also have destroyed many beneficial insects and further aggravated pest problems.

The tobacco budworm, Heliothis viresccns (F), is a serious pest of tobacco and cotton in the southeastern United States. In California it is primarily a pest on floral crops; damage results from larvae feeding on flowers, young leaves, and stems, greatest damage occurring when infestations are heavy. High populations of budworms can cause plants to become stunted and distorted, thereby reducing the number of marketable cut flowers.

Recent studies in California and Europe have shown that certain leafhoppers can transmit the stubborn disease organism, Spiroplasma citri, after acquiring it by various artificial means. We also know that one leafhopper, Scaphytopius nitridus (DeLong), can acquire the organism by feeding on infected citrus and can then transmit it to periwinkle plants (California Agriculture, January 1975) and citrus.