Did you know? Research was a Major Force for Expanding Dry Bean Production in Nebraska (Part 2)
Robert M. Harveson, Extension Plant Pathologist, and Carlos A. Urrea, Dry Bean Breeder
University of Nebraska Panhandle Research and Extension Center
Editor’s Note: This story is Part 2 of a series describing the major role that research has played in the expansion of dry edible bean production in Nebraska. Part 1 traced some of the highlights from the industry’s beginnings in the 1890s until plant breeder Dermot Coyne’s arrival in 1961. Part 2 covers highlights in dry bean research from 1961 until the present.
Dermot Coyne continues work with plant pathologists
Dermot Coyne arrived at the University of Nebraska-Lincoln in 1961 and conducted research in western Nebraska continuously for the next 40 years, maintaining his dry bean breeding plots at the Panhandle Research and Extension Center in Scottsbluff.
Much of Coyne’s collaborations were with plant pathologists, designing new cultivars with high levels of resistance to several diseases, starting with common bacterial blight via Selection No. 27 from Nebraska No. 1. This specific selection was chosen due to a visible resistant reaction in the field to the disease, and served as a parent for the creation of subsequent new resistant cultivars worldwide.
Coyne determined that the resistance to common blight was associated with late flowering and was inherited quantitatively (through multiple genes). He also evaluated the effects of photoperiodism and temperatures and how they influenced plant responses to common blight.
He also discovered that different plant organs, such as pods and leaves, reacted differently to the two bacterial diseases – common and halo blights – thus, when making selections for resistance, both plant parts were needed for complete evaluations.
He also began work with UNL Plant Pathologist Max Schuster, developing resistance to bacterial wilt in the early 1960s. By 1971, they released the cultivar Emerson after screening more than 1,500 varieties and breeding lines. It conferred resistance to wilt through the late maturing line PI 165078 (Turkey) that was crossed with the early maturing, wilt-susceptible great northern cultivar 1140.
Breeding lines derived from this cross were evaluated under field conditions and Neb. BW-68-45 was selected for release as Emerson, a bright white, large-seeded cultivar exhibiting high levels of wilt tolerance. Today, 46 years later, this cultivar is still being used for specialty markets, such as Spain and southern France.
Coyne and Schuster also collaborated with bacteriologist Anne Vidaver to develop Star after multiple backcrossings of the selection No. 27 of Nebraska No. 1, which combined resistance to four diseases – wilt, common blight, halo blight, and bean common mosaic.
With the arrival of plant pathologist Jim Steadman in 1969, Coyne began breeding new cultivars with better resistance to white mold and rust, which were becoming more problematic in the High Plains. After crossing a black bean, Tacaragua, with great northern and pinto germplasm sources, they demonstrated that newly created lines were able to avoid white mold infection.
This bean also contained a gene for resistance to rust, which is still valid today in the High Plains. During his long, distinguished career, Coyne was able to produce new great northern and pinto cultivars and lines with resistance to six diseases, which were also combined with important agronomic features such as high yields with excellent seed quality.
Carlos Urrea joins UNL
Carlos Urrea was hired in 2005 to replace Coyne as the dry bean breeder for UNL, and was newly stationed in Scottsbluff rather than Lincoln. He continued a close working relationship with Steadman on developing enhanced disease resistance to white mold, rust, bean common mosaic, and common blight in new bean cultivars.
Urrea is further developing new lines with better tolerance to drought and heat, in the hope that beans could be grown in some years as a dryland crop, further expanding the acreage. Urrea has released several new cultivars with multiple disease resistance, including great northern Coyne and Panhandle Pride, light red kidney Panhandle Red, and the upcoming slow-darkening pinto Monarch.
He also released several germplasm lines, including two black bean lines TARS-MST1 and SB-DT1, with multiple stress tolerance, and great northern ABC-Weihing with high levels of common bacterial blight resistance.
Contemporary breeding/pathology research and collaborations
Over the last decade, Urrea has further collaborated with plant pathologist Bob Harveson with evaluating Phaseolus (common bean) germplasm collections for resistance to wilt and bacterial brown spot, with the ultimate goal of new cultivars resistant to these two diseases.
Harveson’s program identified a fourth color variant (pink) from western Nebraska in 2008. The new strains (color variants) of wilt (pink, orange and purple) were all found first in western Nebraska after the first report of the wilt disease in South Dakota was a yellow strain. The orange and purple variants are now found worldwide wherever beans are grown.
Curiously, the pink strain is yet to be reported from anywhere else but Nebraska. Harveson has also recently been assisting in the identification of a new red-colored variant from Iran which has not been discovered anywhere else as yet.
Urrea is now making crosses from promising germplasm lines after screening thousands of them against multiple bacterial isolates to create new cultivars with resistance to wilt (all color variants except for red), brown spot, and fuscous blight. Brown spot has emerged over the last five years as a serious and often recurring disease problem throughout the region. Fuscous blight, another disease making a comeback now, is caused by a variant of the common blight pathogen that produces a diffusible, brown pigment that stains seeds.
Lastly, Urrea and Harveson have worked for more than 10 years to develop a new garbanzo bean (chickpea) adapted for this area, called New Hope, with excellent resistance to Ascochta blight, which will be released in 2017. They also released another resistant garbanzo line PREC-CA-Comp. No. 1 in 2011.