Drought and Turfgrass Breeding Trials

Posted on 11/01/11

COLLEGE STATION – A green checkerboard at the new Turfgrass Urban Ecology Field Laboratory in College Station is a project to develop new cultivars of major turfgrasses with improved drought and salinity stress tolerance.

Dr. Lloyd Nelson, professor emeritus in turfgrass, and Dr. Ambika Chandra, a Texas AgriLife Research assistant professor of turfgrass breeding in Dallas, discuss the different plots at a recent field day.

Dr. Ambika Chandra, a Texas AgriLife Research assistant professor of turfgrass breeding and molecular genetics in Dallas and the principal investigator of this project, is working under a $3.8 million grant from the Specialty Crops Research Initiative program sponsored by the U.S. Department of Agriculture National Institute of Food and Agriculture.

“The main idea is that five universities in the south and southeast have gotten together with one goal in mind – to develop cultivars of turfgrasses that are drought as well as salinity tolerant,” she said.

Chandra and Dr. Lloyd Nelson, professor emeritus in turfgrass, have AgriLife Research turf plots at both Dallas and College Station. They are collaborating with scientists from North Carolina State University, Oklahoma State University, University of Georgia and University of Florida on the five-year study.

Dr. Ambika Chandra, a Texas AgriLife Research assistant professor of turfgrass breeding, shows how some of the 4-inch plugs of grass failed to spread while others filled out the 3-foot-by-3-foot plots. (Texas AgriLife Research photo by Kay Ledbetter)

In the first year of the project, 160 different experimental genotypes of Bermuda grass, zoysia grass and St. Augustine grass and 80 genotypes of seashore paspalum grass were planted, Nelson said. Ryegrass germplasm or experimental lines were planted this month.

These lines are not ready to be released to the public, he said, but they are ready for evaluation by the participating universities at multiple locations throughout the southern U.S.

“We want to develop cultivars that are drought and salinity tolerant that can be used in parks, golf courses, home lawns and commercial landscapes,” Chandra said. “We want to provide the best to our producers, consumers and industry.”

She said breeding is the answer to these two issues – drought and salinity – because a chemical can’t be developed to fix either of them, as is the case in controlling disease and insect pest damage. And, the freshwater supply is limited and increasingly more expensive.

“It is becoming necessary to use water of lesser quality on your turf and landscape,” Chandra said. “That’s why we are doing this, and why these seven breeding programs in the southern region are working collaboratively under this project.”

By evaluating the same plant material under different environmental conditions, breeders can determine the range of adaptation and identify breeding lines best suited for regions across the south and the southeast.

This first year got the plots established, using full fertilizer and irrigation, Nelson said.

“A 4-inch plug was planted to fill each 3-foot-by-3-foot plot,” Chandra said. “You can already see the differences in the amount they have spread, the color, the density of the grass – these are the things we are taking notes on this year.

“We will start stressing it for moisture next summer and begin our evaluation for heat and drought tolerance,” she said. “We will also look at winter kill this winter.”

Chandra said next summer another set of experimental germplasm will be evaluated for all five grasses at all seven locations.

In the third and fourth years, the best material from these first-year plots, as well as those planted next year – regardless of what program it came from – will be replicated in larger field plots, Chandra said. Selected genotypes also will be evaluated in greenhouses for salinity stress tolerance and will be grown under rain-out shelters to determine their drought stress tolerance.

“The idea is to select the 3 to 5 percent ‘good performers’ each year and then that material will be studied in further detail on larger plots at all five universities,” she said.

“The goal is to identify and increase the best genotypes and eventually release them as cultivars for the turfgrass industry.”

from AgriLife TODAY (Oct 27, 2011) by Kay Ledbetter, photo of Dr. Lloyd Nelson and Dr. Ambika Chandra by Kay Ledbetter