Press Release 1
Press Release 2

FOR IMMEDIATE RELEASE: July 25, 2006
CONTACT: Janet Byron, (510) 987-0668 or janet.byron@ucop.edu

July-September 2006 California Agriculture magazine
Selected high-resolution images from this issue are available here

Press Release 1:
When transgenes wander, should we worry?
Just like their traditionally bred counterparts, transgenic crops have definitively been shown to crossbreed with crops or native plants growing nearby.
In the July-September issue of the University of California’s California Agriculture magazine, a peer-reviewed review article documents widespread evidence that crop transgenes do, in fact, wander in the environment.
But is this is cause for worry?
“The products of traditional plant improvement are not absolutely safe, and we cannot expect transgenic crops to be absolutely safe either,” writes Norman C. Ellstrand, director of the Biotechnology Impacts Center and genetics professor at UC Riverside. “The creators of transgenic plants need to be as mindful of possible problems with their products as they are of potential promise.”
With the issue, California Agriculture launches a special series on the risks and benefits of agricultural biotechnology, with three peer-reviewed research articles focusing on transgenic crops, fish and animals. (Future issues will examine transgenic insects, pharmaceutical crops and other concerns.)The full articles are posted online at http://californiaagriculture.ucop.edu
Transgenic plants are engineered with genes from other plants or organisms to express agronomically desirable traits, such as herbicide or insect resistance, or higher vitamin levels. In 2005, the world’s billionth acre of transgenic crops was planted; most of that acreage was in the United States, primarily in corn, soybeans and cotton.
Ellstrand, author of the 2003 book Dangerous Liaisons? When Cultivated Plants Mate With Their Wild Relatives (Johns Hopkins Press), has conducted extensive research on gene transfer among plants, in addition to field studies.
For example, Ellstrand and colleagues showed that one of the world’s most important crops, sorghum, spontaneously hybridized with one of the world’s worst weeds, johnsongrass, even when they were grown up to 330 feet apart; furthermore, the two plants are distinct species with different numbers of chromosomes. Other labs have demonstrated crop-to-wild gene flow with sunflower, rice, canola and pearl millet.
Transgenic crops are no different. Transgenic canola has crossbred with its native relative, creating herbicide-resistant volunteers. A more well-known example is transgenic Starlink corn, which was not approved for human consumption but appeared in a variety of corn-based foods. “For a decade, more than a dozen cases of transgenes and/or their products out-of-place have been reported,” Ellstrand notes in California Agriculture.
In two other peer-reviewed articles in California Agriculture, Alison L. Van Eenennaam, UC Davis animal genomics and biotechnology specialist, examines environmental and public-policy concerns related to transgenic fish and mammals.
To date, just one transgenic fish has been approved for sale in the United States, a red-fluorescent zebra danio for aquariums (California has banned the fish). A growth-enhanced salmon is currently under federal review. Risk factors associated with transgenic fish include unintended release or escape, and related ecosystem imbalances. For example, in one study, “fast-growing transgenic salmon were found to dominate feed acquisition and exhibit strong agonistic and cannibalistic behavior toward their [nontransgenic] cohorts when there were inadequate feed resources,” Van Eenennaam writes.
However, Van Eenennaam notes that “neither the risks nor the benefits of transgenic fish ore certain or universal.” Rather, they vary according to a variety of factors. “Regulators need to apply a scientifically sound, risk-based framework to assess the ecological risks involved with each transgene, species and receiving ecosystem combination on a case-by-case basis.”
No genetically engineered food animals have been approved for global or U.S. sale, although numerous animal species have been cloned (but not sold for food) and transgenic animals are producing commercial, nonfood items such as spider silk (by goats). Van Eenennaam notes that transgenic animals raise unique ethical concerns due to “the special place that animals hold in our society.”
This concern is often at odds with the scientific process, which “places a high value on controlled experiments as a way to obtain understanding,” Van Eenennam writes. She urges scientists to pursue effective and responsible communication with all stakeholders, in order to “reach a consensus on the acceptable levels of risk for specific products of animal biotechnology, and to determine which set of values will ultimately be applied to decide the acceptable uses of animal biotechnology.”

Press Release 2
Conservation tillage helps growers save time, money, the environment:
As fuel prices rise and agricultural profit margins narrow, California farmers may find some relief with conservation tillage, in which growers reduce the number of times that they drive tractors across their fields. Common in the Midwest, conservation tillage is relatively new to California, and UC researchers are working to adapt it to local crops and conditions.
The July- September 2006 issue of the University of California’s California Agriculture journal includes two peer-reviewed research articles and related news coverage on the pros and cons of conservation tillage in California. The full articles are posted in full online at http://californiaagriculture.ucop.edu
“Conservation tillage is not like previous agricultural innovations,” says Jeff Mitchell, UC Cooperative Extension vegetable crops specialist affiliated with UC Davis. “Farmers are not just introducing a single technology; they are changing their entire system of farming. Farmers are doing the frontline trouble-shooting work with support from scientists and agricultural industries.”
While some innovative California growers have adapted conservation tillage to the state’s unique climate and soil conditions, the practice is still relatively uncommon here. (A seminar with California growers who have successfully reduced their tillage will be held Aug. 8 in Sacramento; see below.)
Growers continue to till the soil for a variety of agronomic reasons, Mitchell says, including to manage weeds and diseases, loosen compacted soil, and allow more-efficient furrow irrigation.
However, Mitchell says the potential benefits of conservation tillage are numerous: they include water conservation, dust suppression, reduced pesticide runoff into surface water, lowered labor needs and costs, and fuel savings. In addition, limiting tillage helps to keep carbon in the ground and prevent the buildup of greenhouse gases in the atmosphere. (The UC Conservation Tillage workgroup has nearly 500 members statewide; see http://groups.ucanr.org/ucct)
In California Agriculture, Mitchell and colleagues report on a field study of seven different tillage methods in two back-to-back cotton crops in the San Joaquin Valley, with and without an intervening cover crop. While cotton yields were for the most part comparable in all the tillage systems studied, the reduced-till systems decreased the number of tractor operations by 41 percent to 53 percent, fuel use by 48 percent to 62 percent, and overall production costs by 14 percent to 18 percent.
The other peer-reviewed study published in California Agriculture examines at the effects of different tillage methods on soil quality in a typical San Joaquin Valley cotton-tomato crop rotation, with and without cover crops. The 4-year study found that conservation tillage alone improved some soil parameters, such as bulk density and the availability of nitrogen and phosphorus, but it also significantly increased concentrations of salt and potassium at the soil surface. In this study, however, cover cropping in conjunction with conservation tillage mitigated most of the deleterious effects on soil quality.
“In the low-rainfall regime of the San Joaquin Valley, farmers may benefit more from cover cropping in combination with conservation tillage to maintain soil fertility, as opposed to conservation tillage alone,” wrote authors Jessica Veenstra, former UC Davis researcher, and colleagues.
UC Davis soil scientist William Horwath noted that the effectiveness of conservation tillages varies considerably with crop type, agronomic practices and growing conditions. “California agriculture is more intensive than in the Midwest, which is primarily grain crops and is thus more amenable to conservation tillage,” Horwath says. “Here we have many varied crops requiring specific agronomic practices. It’s not a clear-cut decision, and it may not be for everyone.”
Seminar: A free workshop featuring California conservation tillage innovators will be held at 7 p.m. on Aug. 8 at the Hyatt Regency in Sacramento. For more information, go to: http://news.ucanr.org/newsstorymain.cfm?story=820

Also in the July-September 2006 issue of California Agriculture:

Food choices of black women: A unique study finds that eating habits ­— both positive and negative — are not passed along between grandmothers, mothers and daughters in the same families. The study evaluated the diet and nutritional status of 58 triads of related California black women and found no correlation between generations. “Any influence that one generation might have on the food habits and food choices of subsequent generations appears to be nullified by an ever-changing food supply and an increasingly complex lifestyle,” wrote lead author Joanne Ikeda, a UC Berkeley nutrition specialist.

Cattle prices lower in West than Midwest: An analysis of 7 years of video auction data finds that Western cattle ranchers receive lower prices for cattle than the same animals would fetch in the Midwest, due to the cost of transporting them to Midwestern feedlots and meat processing facilities. However, value-adding programs such as preconditioning and natural beef did raise the prices received by Western ranchers. “The Western cattle industry’s future may involve discovering new market trends and quickly changing cattle management practices to produce a profitable niche product,” wrote lead author Steve Blank, a UC Davis economist