Washington, August 26 : A Texas AgriLife Research scientist is working with crosses between temperate and tropically adapted varieties of corn to develop a drought-tolerant plant that can perform well under reduced irrigation.
"With the continuing decline of the Ogallala Aquifer water level and increasing cost of pumping water, the use of drought-tolerant and high-yield corn hybrids is a key for sustainable corn production under limited irrigation," said Dr. Wenwei Xu, AgriLife Research corn breeder from Lubbock.
A demonstration on the differences between the parent plants and the offspring was made during a field day, held recently at the North Plains AgriLife Research Station near Etter.
"We hope to reduce the amount of water required for corn by at least 10 percent," Xu said.
The researcher revealed that the AgriLife Research program out of Lubbock had already released four inbred lines of corn, and that numerous others were in the process for release.
"The new multiple-stress-tolerant corn lines can be used to produce corn hybrids adapted to Texas and other southern states. They can be a powerful tool to save water and produce crops with yield and grain quality under stressful environments," he said.
According to him, about 500 hybrids would be evaluated this year for either grain yield or silage yield and quality.
Highlighting the increasing demand for silage corn in the Texas High Plains, Xu said that producers needed new hybrids adapted to the local environment.
He said that corn produced in the U.S. was primarily based on two races of maize, but there were more than 250 races identified around the world.
"Most of our breeding efforts start by crossing tropical corn with temperate elite lines. Then we select for desirable traits to broaden genetic diversity and introduce useful genes from exotic corn to improve stress tolerance, agronomic productivity, disease resistance, insect resistance and value-added grain characteristics," he said.
Xu said that some of the experimental hybrids he and his colleagues were working with had produced the same silage yield under irrigation equalling 75 per cent evapotranspiration as with 100 per cent evapotranspiration irrigation.
Bruce Spinhirne, AgriLife Research associate based in Lubbock, said that the research team reduced the irrigation on a few hybrids by 50 per cent, and had a severe yield and quality limitation.
Thus, he added, the team followed that by the 75 per cent water application.
The researcher further said that the results were due in part to the use of stored moisture in the soil profile.
"At 75 percent (evapotranspiration), you have 3 to 4 inches of available moisture that is used, where if you are watering at 100 percent, it is wasted," he said.
Spinhirne revealed that the average silage yield of 20 corn hybrids at two locations - Etter and Halfway - was 26.84 tons per acre under 75 per cent evapotranspiration irrigation, just slightly lower than the 27.49 tons per acre under 100 per cent evapotranpiration irrigation.
He, however, agreed that there were significant differences among hybrids in each environment.
"One of our experimental hybrids produced the same amount of silage in both locations when irrigation was reduced from 100 percent to 75 percent," he said.
"Developing and using new corn hybrids with improved tolerance to drought and other stresses is important and a viable water-saving approach," he added.