Dry Bean Breeding Project


Dry Bean Production

   Dry beans have been grown commercially in Colorado for more than 100 years. The primary market class has always been the pinto bean, usually comprising more than 90% of the total crop. Other market classes have been produced, including small read, Anasazi, pink, light red kidney, small white and others. Today light red kidney is the second largest market class, comprising 5 to 15% of total production.

   Pinto beans have been an important crop in Colorado agriculture since production statistics were first compiled in 1909. At that time, 5,00 acres were planted that had an average yield of 580 Ib/A at a price of $3.60/cwt. Pinto bean production increased rapidly thereafter. In 1914, 20,000 acres were planted and by 1917 production increased to 243,000 acres, of which only 40,000 acres were under irrigation. Annual production in Colorado increased from 180,000 cwt in 1914 to 900,000 cwt in 1917. The industry enjoyed steady growth throughout the 20s and 30s, and saw a record high in 1943 with 460,000 harvested acres.  Average yield at that time was 535 Ib/A at $5.70/cwt. From 1970 to mid 1990’s, acreage fluctuated between 120,000 to 225,000 acres annually, and average yields steadily increased to more than 1800 Ib/A. Prices during this period varied from $8.60 to $31.20/cwt. Acreage since the mid 1990s has steadily declined due to low prices. In 2003, the area planted to bean was the lowest since the mid 1910s at 69,000 acres. Prices currently vary between $14 to to 18/cwt. Given that the current cost of production is estimated at $15/cwt, it is clear that the profit margin for the bean crop is minimal and lower prices have reduced the number of acres planted to historic laws. 

Dry Bean Improvement and Breeding

    Alvin Kezer and Walter Sackett were among the first scientists in Colorado to work with dry beans. In 1918, they reported on dry bean production practices in Colorado during the early 20th century in publication “Beans in Colorado and Their Diseases”. Early bean varieties were derived from land races that were grown by Native Americans or imported from other regions, including Mexico. The market class that we recognize today as pinto bean was known by several names during the early years of cultivation including: Mexican, Mexican bean, Mexican bean, Mexican tick bean, Colorado bean, army bean, and others. The name pinto was well established by the mid-20th century, and the pinto is now recognized market class according to USDA Agricultural Marketing Standards.

   Dry bean breeding activities in Colorado during the early 20th century were primarily focused on single-plant selections from land races and varieties that were brought into Colorado. Kezer and Sackett stated that, “…much progress can be made from selection with pinto beans as is sometimes done with corn in the Midwest”. Suggested selection criteria included high individual plant yield, early maturity, uniform ripening of pods, and freedom from disease. The selections were planted in rows, and the highest-yielding rows that had desirable agronomic characteristics were saved for future planting sotck. Kezer and Sackett stated that “Preliminary work with bean selection shows that it is easily possible to increase the yield 25% by selection alone”. Undoubtedly, these early selections produced both higher yield and better disease resistance that in early varieties.

     Pinto beans were also very important in the San Juan Basin of south central Colorado during the early 20th centuary. Early varieties were also derived from land races imported from other regions, especially the highlands of Mexico. During the 1930’s, pinto bean varieties such as San Juan showed severe symptoms of bean common mosaic virus (BCMV) infection. Dwight Koonce, who worked on beans for Colorado A&M at Hesperus, CO, cooperated with a local bean grower Homer Norton to identify and select disease-free plants in the field. Their work led to the release of the variety “San Juan Select” , a virus-resistant variety, the most widely grown pinto in the region until the early 1980’s, when the pinto variety “Cahone” was released by CSU. Today, a small amount of acreage is still planted to San Juan Select in the San Juan Basin.

Origin of the Breeding Program

    The first formal breeding program at CSU was first proposed in 1948 by Donald Wood. Don was hired as an Assistant Professor in 1947 to assist Dr. Warren (Red) Leonard with the barley breeding, and to help teach an undergraduate genetics course in the Department. In a draft proposal titled “A Plant Breeding Program for the Improvement of Pinto Beans in Colorado”, Wood stated that “The objectives of the bean improvement program should be to: 1) Further study the bacterial blight organism, 2) Develop and maintain a Colorado pinto bean seed industry, 3) Breed for resistance to the rust pathogen, 4) Study improved cultural practices, and 5) Breed for improved resistance to bean common mosaic virus and curly top (an aphid transmitted virus disease)”.

Don Wood recalled his first years at Colorado A&M as follows:

“My appointment as Assistant Agronomist in Colorado Agricultural Experiment Station began January 1, 1947. I can still remember the beautiful snow that fell during the preceding Christmas holiday as contrasted to the wind-driven blizzards of my Kansas experience. I was assigned to assist Warren H. Leonard in his Genetics classes, develop an MS thesis problem with Ralph Weihing, teach Crops Laboratory, and audit the other crops courses being taught. Two other graduate students joined the Department soon after I came, Ronald Ensign and Robert Osler. We were all pursuing MS degrees. I was  under Dr. Leonard’s tutelage, Osler was “Scotty” Robertson’s student, and Ron Ensign also worked under Robertson on barley”.

    In 1946, a severe rust epidemic occurred in eastern Colorado. At that time, Dr. William (Bill) Zaumeyer, a USDA scientist working on beans at the Potato Research Station in Greeley, Colorado, studied the rust pathogen and conducted a breeding program to improve garden and pinto beans for the western US. Dr. Zaumeyer spent summer months in Greeley conducting field plots and winter months at Beltsville, MD conducting laboratory and greenhouse research. He made crosses during the winter in Beltsville, MD and planted the progeny in Greeley for evaluation and selection. Dr. Zaumeyer planted about three acres of garden beans and once acre of pinto beans in his search to find new sources of resistant genes and improved varieties. After the epidemic, Dr. Zaumeyer requested funding from the Colorado State Legislature to work on control mechanisms for rust and incorporation of rust resistant genes and incorporation of rust resistance into pinto bean. In 1947, Bill Zaumeyer found the perfect stage of rust and convinced the Colorado State Legislature to provide $10,000 to fund bean research. From these funds, research on control methods using sulfur and variety testing were initiated. The following years, economic damage to the bean crop due to bean rust was significantly reduced due to timely applications of sulfur at the first sign of rust.

    Graduate Research Assistant Ron Ensign also conducted a variety testing program that included new lines developed at the University of Idaho and resistant strains from Zaumeyer’s program. According to Don Wood, “Bean varieties from Idaho had a growth havit that was attractive to the growers and although suspectible to rust, they soon became the choice of farmers in the eastern irrigated countries”. Zaumeyer and his assistant, H. Rex Thomas, worked hard to get an agronomic type equal to the Idaho varieties with rust resistance. During the latter part of the 1940’s, Bill Zaumeyer wanted to reduce his travel to Greeley in the summer, so he worked out an agreement with Don Wood to have the USDA package seed of pinto breeding lines and mail them to the Colorado for planting, evaluation, and selection. Eventually, Don Wood planted the entire Zaumeyer nursery. From these efforts the variety “Scout” was released; however Scout was not widely grown because it did not have the agronomic desirability that was available in the pinto varieties released from the University of Idaho, namely UI 71, UI 78 and UI 111.

          In 1950, Don Wood pursued a PhD at the University of Wisconsin. Don recalled the day he left for Wisconsin to start his studies; “As I was driving out of town, I heard about the invasion of South Korea by North Korea on the radio. Because I had served in the Marine Crops during WWII, I thought that I may as well turn around and return home because I would be recalled to duty. However, I kept on driving and the recall never occurred.” At the UW, Don studied corn genetics and the genetic mechanism involved in variegated seed color. In 1956, he completed the PhD degree and returned to CSU.