Steve Koike on Resistant Cultivars

The Search for Resistant Cultivars

By Emily McKay Johnson, Associate Editor

In the second part of our series with Steve Koike, plant pathology farm advisor for UC Division of Agriculture and Natural Resources, Cooperative Extension in Monterey County, the focus is on the critically needed research on resistant cultivars. Koike, who has focused his research since 1989 primarily on the understanding of disease systems and the investigation of new methods of disease control, said, “The role or the need for resistant cultivars is tremendous.”

“Some good case studies of resistant cultivar research address soil-born problems on lettuce,” Koike explained. “For example, Fusarium wilt and Verticillium wilt on lettuce could be managed lightly; but in order to overcome those diseases, resistant lettuce varieties need to be in place.”

Steve Koike, UC Cooperative Extension, Monterey County.

“First discovered in 1995 on the Central Coast,” said Koike, “Verticillium wilt has the potential to infect and damage numerous different crops. And although Fusarium wilt was typically unseen in the San Joaquin Valley, it has recently begun to appear on the Central Coast.”

Continued improvement of management techniques upon discovering initial disease symptoms is necessary, according to Koike. “Symptoms of the disease usually appear on the lower leaves of plants, around the edges, and the areas between the veins can turn a yellowish-brown.”

“Strawberries currently have three really important disease pressures state-wide: Verticillium wilt, Macrophomina (charcoal rot) and Fusarium wilt,” Koike commented. “Even the fumigation tools we have are not cleaning them up 100 percent, so we have problems.”

“We will continue to have problems,” Koike elaborated, “until there are truly resistant strawberry varieties to those pathogens. Plant breeders understand that IPM management of these diseases is so dependent on developing resistant varieties,” he said, “but we’re not there yet. We do not yet have truly resistant lettuce or strawberry varieties out in the field,” Koike said.

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Koike and his fellow researchers discovered a new race of the downey mildew pathogen in spinach that has been designated race 16. While there are some varieties that are supposedly resistant to race 16, Koike noted that there is still more research to be done.

To read the first part of our series on Downey Mildew, click here.

California Ag Today2021-05-12T11:05:54-07:00June 27th, 2016|

Lorsban Under Scrutiny

Chlorpyriphos (Lorsban) Must be Used More Carefully

By Patrick Cavanaugh, Deputy Editor

California Department of Pesticide Regulation (DPR) reports an important, broad-spectrum organophosphate insecticide known as Chlorpyriphos, or Lorsban, may be further restricted due to evidence of potential human health and environmental risks, presence (parts per billion) in some California waterways, and pressure from the EPA. Brian Leahy, director of the California Department of Pesticide Regulation, said, “Chlorpyriphos is an important tool and we know there are important times when you have to use it.”

Registered and widely used in agriculture across the nation for more than 40 years, DPR has made it a restricted-use material. Leahy said, “We are trying to work with the grower community to improve how they use it. We are also working with UC IPM to look at essential needs, but we know that as we look at Chlorpyriphos, we are going to have to put additional restrictions on it.”

“We simply need for it to stay on target, and not be getting into the human body. We are seeing that it is, and we are going to continue to make sure that people use it thoughtfully and wisely,” he said.

And Leahy is very confident that growers can use this material and keep it on target, “I have seen farms that use it only when they really need it, and that is what we want. We can’t lose this tool and we are going to keep it only by showing we can greatly reduce off-site movement to the human body and watersheds,” he noted.

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Resources:

According to the University of California Agriculture and Natural Resources 2014 Chlorpyrifos Report entitled, “Identifying and Managing Critical Uses of Chlorpyrifos Against Key Pests of Alfalfa, Almonds, Citrus and Cotton“:

Chlorpyrifos plays a critical role in many IPM programs for controlling pests that threaten the productivity and economic well-being of California producers and in maintaining the high quality standards required by consumers and international export markets. This active ingredient also allows production of animal feed to support the important dairy industry in California. For some pests, chlorpyrifos is one of the last effective organophosphate insecticides available and may provide an important alternative mode of action for insecticide rotations to prevent the development of resistance to newer insecticide products. For others, this product is one of very few products with international registrations with established maximum residue limits (MRLs) that allow unhampered trade. Chlorpyrifos may also be a key tool for controlling invasive pests as well as endemic pests occasionally found in extremely high population densities.

The California Department of Pesticide Regulation reports that the combined use of chlorpyrifos in alfalfa, almonds, citrus, and cotton has decreased since 2006.

Although newer insecticides are also available to manage some pests in these four crops, there is a continued need to preserve the availability of chlorpyrifos for specific situations.

“Assessing the Health Risk of Pesticides,” California Department of Pesticide Regulation

California Ag Today2021-05-12T11:03:04-07:00February 16th, 2016|

Subsurface Drip Efficiency

Subsurface Drip Efficiency in Pomegranates

By Charmayne Hefley, Associate Editor

Subsurface drip irrigation, a more efficient form of water delivery, is growing in popularity and utilized on a widening range of crops. Claude James Phene, a research consultant for the UC Cooperative Extension, said subsurface drip efficiency is evident with both water and nitrogen in pomegranates.

Using a lysimeter, a big box on a calibrated truck scale that measures evapotranspiration, Phene can calculate the precise water requirement for pomegranates according to the soil moisture feedback indicated by the machine. Based on these calculations, Phene can make clear water recommendations to growers so they can accommodate the needs of their plants without exceeding them.

Because it is buried and targeted, subsurface drip irrigation also helps control weeds and reduce animal and traffic disturbances.

This six-year study has also demonstrated these drip lines prevent leaching—the loss of nutrients in the soil—that occurs with other types of irrigation systems. Phene explained, “The lysimeters are equipped with a drop-tube at the bottom so we can measure the nitrogen in any output to determine how much leaching occurs and to make recommendations on fertilizer.”

Patrick Cavanaugh2016-05-31T19:27:04-07:00November 4th, 2015|

Winegrape Rootstock Trials

Winegrape Rootstock Trials for Pest Resistance and Vine Productivity

By Patrick Cavanaugh, Deputy Editor

Larry Bettiga, a viticulture farm advisor with UC Cooperative Extension, Monterey County, is working with county growers on winegrape rootstock trials to increase vine productivity.

“Several things have happened,” noted Bettiga,“we are replanting vineyards on former vineyard lands, where a build-up of soil pests already exists. Farmers used to grow a lot of beans and tomatoes in the Valley, so we’ve had a lot of root-knot nematode populations from past cropping patterns.”

“We’ve recently seen ring nematode populations developing at multiple vineyard sites,” Bettiga continued. “With the loss of more effective fumigants, and then the loss of post-plant-type nematicides, the use of nematode-resistant roots is becoming more critical to the success of replanting these vineyards. We have hopes that Andy Walker, a UC Davis viticulture professor and grape breeder, is going to supply us with some better options than we currently have.”

“We have a site where we are comparing five new rootstocks that were released from UC Davis with a number of our standard rootstocks. We are just starting that work, so obviously we have to look at them for several years to get a good feel for how those stalks will fit in comparison to what we are now using,” he noted.

California Ag Today2016-05-31T19:27:05-07:00October 30th, 2015|

ADAMA Captan Gold ® 4L Now Registered in California

ADAMA Captan Gold ® 4L Fungicide Gets EPA “Go Ahead” for California Strawberries, Tree Fruits

ADAMA has received EPA approval for Captan Gold 4L liquid fungicide for use on strawberries, tree fruits and other specialty crops. A multi-site contact fungicide, Captan Gold 4L penetrates fungal spores, protecting high-value crops against tough diseases like anthracnose, botrytis (gray mold), brown rot and scab.

“ADAMA Captan Gold 4L is the only liquid captan with a ‘Caution’ signal word,” states the company’s national marketing leader Sara Zinck. “Backed by more than 50 years of captan manufacturing experience, Captan Gold 4L delivers excellent efficacy through its multi-site mode of action, making it a trusted partner in fungicide resistance management.”

Gray Mold on Strawberry, UC IPM

Captan Gold 4L on strawberries

For use on California strawberries, Captan Gold 4L is labeled for applications at 2 to 3 quarts per acre. Early applications at pre-bloom and bloom offer the best fruit protection from botrytis. Follow up applications can be applied at 7 to 14 day intervals up to harvest. Application rates are not to exceed 24 quarts per acre per crop cycle.

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ADAMA Agricultural Solutions Ltd (formerly Makhteshim Agan Industries) is a leading global manufacturer of crop protection solutions. With a comprehensive range of high-quality, differentiated and effective products, ADAMA strives to provide accessible, easy-to-use solutions that simplify the user experience while improving crop yields.

For more information, call 866-406-6262 or visit Adama.com.

Featured photo: Strawberries, UC IPM

California Ag Today2016-05-31T19:28:14-07:00June 16th, 2015|

AGRICULTURAL AWARDS – 2013 World Food Prize

2013 World Food Prize Winners

Three distinguished scientists — Marc Van Montagu of Belgium, and Americans, Mary-Dell Chilton, Founder and Distinguished Science Fellow, Syngenta Biotechnology, Inc.; and Robert T. Fraley, Executive Vice President and Chief Technology Officer, Monsanto—share the 2013 World Food Prize for their independent, individual breakthrough achievements in founding, developing, and applying modern agricultural biotechnology.

Their research, which makes it possible for farmers to grow crops with improved yields, resistance to insects and disease, and the ability to tolerate extreme variations in climate, can play a critical role as we face the global challenges of the 21st century of producing more food, in a sustainable way, while confronting an increasingly volatile climate. The pioneering work of these three contributed to the emergence of a new term, “agricultural biotechnology.”

With particular ties to California, Dr. Robert T. Fraley, conducted post-doctoral research in biophysics at the University of California-San Francisco. Fraley led the successful introduction of genetically engineered soybeans that were resistant to the herbicide glyphosate, commercially known as Roundup. When planting these “Roundup Ready” crops, a farmer was able to spray an entire field with glyphosate—and only the weeds would be eliminated, leaving the crop plants alive and thriving.

The World Food Prize is the foremost international award recognizing— without regard to race, religion, nationality, or political beliefs—the achievements of individuals who have advanced human development by improving the quality, quantity or availability of food in the world.

The Prize recognizes contributions in any field involved in the world food supply — food and agriculture science and technology, manufacturing, marketing, nutrition, economics, poverty alleviation, political leadership and the social sciences.

The World Food Prize emphasizes the importance of a nutritious and sustainable food supply for all people. By honoring those who have worked successfully toward this goal, The Prize calls attention to what has been done to improve global food security and to what can be accomplished in the future.

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Agriculturalist of the Year,

Fresno County

The Fresno County Farm Bureau announced that The Greater Fresno Area Chamber of Commerce and Baker, Peterson & Franklin, CPA announced that Supervisor Phil Larson was selected as the 2013 Agriculturalist of the Year, an award given annually to individuals who exemplify leadership and integrity in the Central Valley’s agricultural business community.

Supervisor Larson, a lifelong farmer and Fresno County resident, has had a long and distinguished career with the Wilbur Ellis Company and retired in 2000. His list of community involvement is extensive and includes: President, Fresno County Farm Bureau; Charter member, California Agriculture Production Consultants; California Farm Bureau District 7 State Director; and Fresno City/County Chamber of Commerce.

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Baker, Peterson & Franklin Ag Business Award

The Greater Fresno Area Chamber of Commerce and Baker, Peterson & Franklin, CPA also announced Gar Tootelian, Inc., of Reedley was awarded the 2013 Baker, Peterson & Franklin Ag Business Award, an award to a for-profit service or product-related agribusiness or farming entity headquartered in the Central San Joaquin Valley whose achievements and impact have significantly contributed to the industry and the local community.

Established in 1949, Gar Tootelian, Inc. still prospers as one of California’s oldest and largest independent agricultural chemical and fertilizer retailers. Second generation and family owned, it serves over 1,400 growers from Madera to Kern County.

Gar Tootelian provides advanced, environmentally safe, bio-technology and crop services available. Crop Life magazine recognized Gar Tootelian as the largest, single location, ag retailer in the nation, and they were named in the 10 Best Companies to work for in the Central Valley by a Business Journal survey.

At the Ag Awards Luncheon on Wednesday, November 13 at Radisson Conference Center in Fresno, the Baker, Peterson & Franklin Ag Business Award and the Fresno Chamber Agriculturist of the Year Award will be presented.

Luncheon tickets are available through the Fresno Chamber of Commerce, www.fresnochamber.com, (559) 495-4800.

Source: Fresno County Farm Bureau, CA Avocado Society

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Award of Honor, California

Avocado Commission

At its 98th annual meeting, the California Avocado Society (CAS) presented the 2013 “Award of Honor” to California Avocado Commission (CAC) Vice President of Marketing Jan DeLyser,CAS President.

“Jan DeLyser has specifically focused on the California avocado industry for the past 15 years. Her entry into the California avocado industry came at a difficult time, when foreign imports cast an ominous shadow over our livelihoods,” said CAS President Chris Ambuul. “In just 15 years, US consumption has increased five-fold, and we are still in business. Jan hasn’t just left a mark on our industry; she is a big reason why we are all still here.”

Ambuul noted that the CAS award recognizes outstanding contribution and dedication to the California avocado industry.

The California Avocado Society came into being on May 15, 1915 to promote efficiency of production and orderly marketing toward assuring long term profitability for the business of avocado growing.

Patrick Cavanaugh2021-05-12T11:03:07-07:00October 18th, 2013|