Figure 1. Ascochyta blight on garbanzo bean leaves.

Figure 2. Ascochyta blight on garbanzo bean pods.

Figure 3. Alfalfa mosaic virus in garbanzo beans.

Figure 4. White mold on garbanzo bean stem.

A pest control advisor recently contacted us to ask what pests he should be scouting for in garbanzo beans. His clients had not grown garbanzos in the past but have some acreage this year. Given recent wet weather and relatively mild temperatures, there are three diseases for which we suggest keeping an eye out.

Ascochyta blight (Ascochyta rabiei, Didymella rabiei) is a particular problem in garbanzo beans in wet years, like what we've been having this year. Ascochyta blight can occur at any stage of growth and on any aerial part of the plant. Brown lesions on the stems can cause damping-off symptoms in seedlings or can cause stems to break. At the advanced stage of the disease, concentric circles of spores will form within brown leaf lesions, and these are a good diagnostic characteristic (Figure 1). These concentric circles can also be seen on seed pods (Figure 2), which can result in poor seed set, seed discoloration, and shrinkage. If these beans are used for seed, subsequent crops can get infected. Management of Ascochyta is through the use of tolerant varieties, crop rotations, certified disease-free seed, always using a seed treatment (Mertect), and foliar fungicides. Foliar fungicides, such as Headline or Quadris, should be applied at the first sign of the disease and reapplied if rainy weather is forecasted.

Alfalfa mosaic virus is another disease that could infect garbanzo beans. Alfalfa mosaic virus has a wide host range and is transmitted by aphids. Different strains of the virus may cause symptoms as varied as necrotic spots on leaves to yellow dots or mottling on the entire plant, which can stunt plants or result in pod distortion. Treatment is not recommended for either alfalfa mosaic virus or for the aphids that vector it. Aphids may taste the garbanzo plants but are either killed or deterred by the acidic exudate of the plant, so it is not economical to treat for them. Instead, planting date is important to avoid aphid flights. There are no patterns of infection in fields. Infected aphids land on plants, transmit the disease and then die, so healthy and dying plants may be next to each other (Figure 3).

Lastly, white mold (Sclerotinia sclerotiorum and S. trifoliorum) may be a problem in garbanzos this year, like Ascochyta blight, because of the wet conditions. White mold may appear as a watery rot on stems, leaves, and pods. White mycelium may grow on the stem near the soil line where conditions are moist (Figure 4). Yellow flagging of leaf tissue may appear where stems have been killed. The fungus spreads under moderate temperatures and especially where canopies are dense. Management is through rotations with non-host crops (small grains, corn), and by applying fungicides, such as Endura, during the flowering stage.

Information on products and practices is for educational purposes only and does not constitute an endorsement or recommendation by the University of California.

Pulses are leguminous crops harvested solely for the dry seed. They include dried beans, lentils, and peas – those staple, nutritious and humble foods that our ancestors began cultivating more than 10,000 years ago.

The United Nations strives to raise awareness about pulses through its slogan, “Nutritious Seeds for a Sustainable Future.” The goals: to draw attention to the protein power and health benefits of pulses, to encourage global food-chain connections to better utilize pulses, to boost the global production of pulses, to better utilize crop rotations, and to address the challenges in the trade of pulses.

In California, farmers, the dry bean industry, and UC Agriculture and Natural Resources (UC ANR) researchers are doing their part with research and outreach programs that focus on dry bean production. Our state produces four classes of dry beans, including garbanzos (chickpeas), limas (baby and large), blackeyes (cowpeas), and common beans (such as kidney and cranberry) planted on a total of 50,000 acres and valued at about $70 million.

While not a big economic force like some crops, beans are nonetheless very important to our farming industry. They are needed in crop rotations to help control weeds and they improve soil health by adding biomass back into the soil after harvest and by fixing nitrogen. As such, pulses can contribute to climate change mitigation by reducing dependence on synthetic nitrogen fertilizers. Beans also are an important part of our food security. For example, California lima growers produce virtually all of our nation's dry limas, as well as 60 to 80 percent of the world's market.

Current UC ANR research focuses on improving integrated pest management of dry beans with minimal impacts to the environment. This includes collaborative studies with UC Davis and UC Riverside scientists to breed pest and disease resistant dry bean varieties that have both high yields and quality. Two new releases of garbanzo beans are expected this year. Additional projects focus on drought and heat tolerance in our warming world.

The new UC ANR Agronomy Research and Information Center website features the many agronomic crops grown in California, including beans. Resources available include current research work, cost of production studies, crop production guidelines, and a database of research supported by the California Dry Bean Advisory Board that goes back more than three decades. Stay tuned for additional resources, including online fertilization guidelines for dry beans, to help develop Farm Nutrient Management Plans, as well as the 2016 Integrated Pest Management (UC IPM) Guidelines for Dry Beans. (Click here for the current IPM guidelines)

Meanwhile, let us all join forces with the United Nations, UC ANR, and our state's Dry Bean Industry to raise the awareness of the benefits of pulses for a more sustainable world. This starts with adding more beans to our diet. Beans are packed with nutrients. They are high in protein, low in fat, and rich in fiber. They can lower cholesterol and help in the control of blood sugar and in managing diseases like diabetes, heart conditions and obesity.

Experiment. Prepare bean burritos often, use a variety of beans in your favorite chili recipe, try humus as a delicious vegetable dip, and garnish your salad with beans. The California Dry Bean Advisory Board website provides terrific bean recipes at http://www.calbeans.org. This we know: beans are pulses vital to our diets, just as our pulse rate is vital to monitoring our health.

Fall 2015 harvest is in full gear!

• UCR Blackeye Progress Report, 2015
• Garbanzo Bean Progress Report, 2015
• Lima Bean Progress Report, 2015
• United Nations proclaims 2016 as the "International Year of Pulses"