From superweeds to Pierce’s disease: California Agriculture reports on fighting diseases and pests

Feb 6, 2015

California agriculture is unique and diverse — and so are its pest and disease problems. Take herbicide resistance. While in the rest of the country herbicide resistance problems center on broadleaf weeds in corn, soy and wheat, in California the greatest problems are found in grasses and sedges in orchards, vineyards and rice fields. Herbicide resistance among California crops also varies widely. In vegetable fields, for instance, resistance is not a serious problem and is unlikely to become one.

An article in the current issue of California Agriculture, the peer-reviewed journal from the University of California Agriculture and Natural Resources, examines the spread of herbicide-resistant weeds in California and shows how UC researchers and Cooperative Extension specialists are helping growers to understand and manage the factors that drive it.

Five more articles in this special issue of California Agriculture highlight the work of UC Agriculture and Natural Resources on pests and diseases that threaten the state's people, agriculture and natural resources. The commitments to research and outreach profiled in the issue include the Endemic and Invasive Pests Strategic Initiative, the UC Statewide IPM Program and several successful collaborations with regulatory agencies and the agricultural community.

Excluding pests and pathogens

Diagnostics in animal health: How UC helps exclude and minimize impact of livestock pathogens

Whether it's pinkeye, bluetongue or poisonous plants, UC maintains a strong network of laboratories and field experts to protect livestock health in California.

Plant health: How diagnostic networks and interagency partnerships protect plant systems from pests and pathogens

Regional alliances of federal, state and university plant diagnostic labs work together to identify and control disease spread.

Managing newly established pests

Growers, scientists and regulators collaborate on European grapevine moth program

A regulatory program coordinated by government agencies, scientists and growers successfully contained an infestation that threatened California vineyards.

Cooperative efforts controlled spread of Pierce's disease and found genetic resistance

The 1999 arrival in California of a new Pierce's disease vector, the glassy-winged sharpshooter, posed a major new threat to California vineyards and orchards. A 15-year collaborative effort has successfully contained the sharpshooter and led to major improvements in our understanding of the biology of Pierce's disease, including promising advances in the development of disease-resistant grapevine lines.

Maintaining long-term management

Herbicide-resistant weeds challenge some signature cropping systems

Little or no crop rotation and limited herbicide options have contributed to the rise of herbicide-resistant weeds in orchards, vineyards and rice fields.

Over 35 years, integrated pest management has reduced pest risks and pesticide use

The UC Integrated Pest Management Program helps provide management solutions for invasive pests that destabilize IPM programs in agricultural and urban landscapes.

E-edition research article

The cost of the glassy-winged sharpshooter to California grape, citrus and nursery producers

The spread of the invasive insect in the late 1990s led to increased costs and changes in agricultural practices for grape, citrus and nursery producers.

These articles and the entire October-December 2014 issue are available at

California Agriculture is the University of California's peer-reviewed journal of research in agricultural, human and natural resources. For a free subscription, go to or write to

University of California Agriculture and Natural Resources is the bridge between local issues and the power of UC research. UC ANR's advisors, specialists and faculty bring practical, science-based answers to Californians. Visit to learn more.



By Debbie Thompson,, (530) 750-1223
Contact - Managing Editor, California Agriculture