Calag Archive

Air pollution—smog—causes California farmers, principally growers of flowers and vegetables, a total annual loss of approximately eight million dollars in returns from crops rendered unsalable by smog.

Circulation cleaning of food processing equipment—by pumping detergent through it—has been adopted so rapidly in food plant operations that knowledge of basic principles has not kept pace with usage. A research program evaluating : the variables in the cleaning process used films of milk labeled with a radioactive tracer, to simulate the soil to be washed from the equipment.

The pea aphid—Macrosiphum pisi (Kaltenbach)—frequently causes great damage to the spring alfalfa crop in southern California.

Integrated pest control programs combine and integrate natural control factors and chemical treatments. Chemical control is used when necessary but in a manner planned to be the least disruptive to control by predators, parasites, and diseases attacking pests of agricultural crops.

More than 1,200 introductions and commercial bean varieties were tested by inoculation with cultures of the two most prevalent organisms causing root rot in California. Only seven showed some tolerance to the Fusarium fungus, and none to the Rhizoctonia. These seven were crossed with ten commercial bean varieties in most of the 70 possible combinations. Each plant was, graded on severity score of 0-4, and the average scores were used for evaluation. None of the first-generation plants showed resistance. Second-generation plants were tested from 60 of the 70 combinations. These tests indicated that hybrids from three of the resistant lines gave very few plants with low disease scores. Second-generation plants of hybrids from the other four accessions had 16%-19% resistant plants, or a ratio of 13 susceptible to three resistant. These results could be explained by assuming that resistance is due to two independent genes, one dominant and the other recessive. To test this hypothesis, four third-generation combinations were tested. To confirm the assumption, only 1/16 of the third-generation progenies would have disease scores as low as the resistant parent, and 2/16 would segregate three resistant to one susceptible and would have relatively low average scores.

Azalea root rot frequently causes serious plant losses, especially during prolonged cold, wet weather.

Controlled fermentations in wine are under study using special equipment designed to control the temperature, pressure, type and rate of gas or gases sparged into fermenters, and rate and duration of stirring or pumping-over, and allow the submerging of red grape skins for color extraction. For critical work with various yeasts, the equipment can be sterilized under steam pressure. Control instruments record gas flows, pressures, temperatures, and carbon dioxide and oxygen content of gases. Two of these fully controlled fermenters of 25-gallon capacity have been in use for several years. Ten smaller units, each of 7-gallon capacity, are being assembled and will be fully equipped and available to enlarge the area of study within a few years.

One-fourth of all of California's feed-lot cattle are in the Imperial Valley—a seemingly unfavorable environment for livestock production in the summer months. From June through September, daily temperatures average about 90° F., and frequently do not go below 80° F. Air temperatures above the animal's body temperatures may prevail for as long as eight or nine hours every day; and, because of the southern latitude and almost cloudless skies, the solar radiation is intense. But by good management practices involving corrals open to breezes, drinking water as cool as possible, proper rations, and well-designed shades, the Valley feeder has been able to obtain efficient gains.

Dairy cows receiving an all-pellet ration produced slightly more milk but with significantly lower butterfat than did cows eating similar amounts of long hay and concentrates. Butterfat tests were reduced by 0.1% to 0.3%.