California Agriculture, July-August 1992
Volume 46, Number 4
Bt controls tobacco budworm on petunia
peer-reviewed research articles
In the San Joaquin Valley, cotton aphids have become resistant to commonly used pesticides
by Elizabeth E. Grafton-Cardwell, Thomas F. Leigh, Walter J. Bentley, Peter B. Goodell
Laboratory bioassays have demonstrated that cotton aphids are resistant to organophosphate pesticides in many areas Of the Sari Joaquin Valley. Many of the aphids are resistant before they reach newly emerged cotton; their resistance tends to decline at the end of the season. The best management strategy: Avoid using pesticides in spring when they are least effective and natural enemies are abundant, and use pesticides at the end of the season to prevent sticky cotton bolls.
Tobacco budworm, pest of petunias, can be managed with Bt
by Nita A. Davidson, Marvin G. Kinsey, Lester E. Ehler, Gordon W. Frankie
Damage to petunias by tobacco budworm has reduced the popularity of this colorful summer annual in some parts of California. However, properly timed applications of Bacillus thuringiensis (Bt) can effectively manage budworm in home gardens and in greenhouses. Lacewing applications proved ineffective on petunias, but may control tobacco budworm on other plants.
Dietary change among Latinos of Mexican descent in California
by Eunice Romero-Gwynn, Douglas Gwynn, R Barbara Turner, Gwendolyn Stanford, Estella West, Eunice Williamson, Louis Grivetti, Roger McDonald
Mexican immigrants to California and their descendants are maintaining some traditional eating patterns as they incorporate many new foods into their diets, a survey found. There have been modest increases in the consumption of milk, vegetables, and fruits. But not all changes are for the best: consumption of fats, sugar, and sliced white bread is up.
Consumer attitudes toward locally grown produce
by Christine M. Bruhn, Paul M. Vossen, Erin Chapman, Suzanne Vaupel
Can small farmers in California achieve greater profits through promotion of “locally grown” produce? Interviews and sales data indicate that consumers are attracted to locally grown produce, but not if the quality is poor or the price is more than they are used to spending. When markets advertise high-quality, locally grown produce at a fair price, produce sales increase.
Fuji apple, radicchio, basil, walnut top specialty crop research needs
by Stephen H. Brown, Louie H. Valenzuela
Growers and distributors list 130 specialty crops they think need research. Heading the list: Fuji apple, radicchio, basil, and walnut.
Deterring compaction of soil by heavy machinery
by S. K. Upadhyaya
During the last four decades, capital-, chemical-, and energy-intensive agriculture has doubled farm production, while mechanization has reduced agricultural labor by a factor of three. These achievements are not without their problems. For instance, the use of heavy machinery often leads to soil compaction, which in turn is overcome by increasing inputs of energy, chemical fertilizers, and water. All of these practices have a negative bearing on agricultural sustainability. Farmers can deter soil compaction by resorting to reduced tillage or no tillage, using high-flotation tires or steel or rubber-belted tracks on vehicles, or by using controlled-traffic, wide-span vehicles. Additional research could help pin down the right combination of deterrents.
Irrigated warm- and cool-season grasses compared in Northern California pastures
by Melvin R. George, Pefer B. Sands, Charles B. Wilson, Roger Ingram, J. Michael Connor
North American prairie grasses were most productive in a comparative study of irrigated warm-and cool-season grasses. The high yield and later peak in production of warm-season grasses make them ideal for increasing the productivity of irrigated pastures in California. All grasses in the study survived reduced irrigation. Grazing cattle preferred dallisgrass over all other grasses.
Fight weeds and increase forage: Using oats as a companion crop in establishing alfalfa
by W. Thomas Lanini, Steve B. Orloff, Ronald N. Vargas, Jack P. Orr
During alfalfa stand establishment, an oat companion crop helps fight weeds and can increase first-cutting forage yield, experiments indicate. No long-term negative impacts on alfalfa production were observed.
Paving the way to a better artichoke
by Wayne L. Schrader, Keith S. Mayberry, David W. Cudney
Significant yield increases were achieved when a seed-propagated, thornless artichoke cultivar was developed for winter production in coastal and desert regions of Southern California and Arizona. The new cultivar was compared to commercial seed-propagated artichoke cultivars. Through research on fertilization, spacing, and weed control, scientists developed guidelines for producing these artichokes as annuals.
Brown-bagging Granny Smith apples on trees stops codling moth damage
by Walter J. Bentley, Mario Viveros
In a 2-year study, thinning Granny Smith apples to one per cluster and covering them with brown paper bags when they were the size of a golf-ball resulted in significantly fewer fruits damaged by codling moth compared with fruits hand-thinned and left untreated. Sunburned fruit were also reduced both years by bagging, and fruit firmness and sweetness were improved in 1 of the 2 years. A similar experiment is now underway with Fuji apples.
editorial, news, letters & science briefs
Veterinary medicine in service to animal agriculture
by Frederick A. Murphy