Chickpeas, high in protein, fiber and other nutrients, are important legume crops the world over. But humans aren't the only consumers: the larval stage of the beet armyworm moth likes to eat the crop's leaves.
But new lines of resistant chickpeas developed by Agricultural Research Service (ARS) scientists and their collaborators could put the kibosh on this crop-damaging pest's voracious appetite, and potentially save on chemical insecticides used to fight it.
The so-called "CRIL-7" chickpeas were conventionally bred from a cross between wild and cultivated species by a team of scientists from the ARS Plant Germplasm Introduction and Testing Research Station in Pullman, Wash.; Washington State University's Department of Horticulture and Landscape Architecture, also in Pullman; and the International Crops Research Institute for the Semi-Arid Tropics (ICRISAT) in Patancheru, India.
ARS entomologist Stephen Clement led the project under a three-year grant from the U.S. Agency for International Development that concluded in December 2008. The Pullman lab was an apt choice because of its scientific expertise and extensive collection of desi and kabuli chickpeas from around the world.
Fred Muehlbauer, now retired from ARS, crossed the wild species Cicer reticulatum, known for its broad insect resistance, with the susceptible cultivar FLIP 84-92C. From seven generations of offspring plants, Clement selected 42 lines offering the best combination of agronomic characteristics and resistance to the beet armyworm, a major pest in India, which in 2005 led the world in chickpea production with 6.6 billion tons.
In 2006-07 greenhouse trials, 28 to 62 percent of beet armyworms that fed on the leaves of resistant chickpeas died within a few days of hatching from eggs. The surviving worms were smaller and shorter than usual. The CRIL-7s outperformed commercial cultivars used for comparison of resistance, but still require agronomic testing under field conditions as the next step towards commercialization, adds Clement.
Clement co-authored a paper reporting the discovery of resistance in the Journal of Applied Entomology.
ARS is the principal intramural scientific research agency of the U.S. Department of Agriculture.