Purdue University scientists working to make drought-resistant crops

Purdue University scientists are working in several areas in the hope that future dry spells don't have the same effects on crops as this year's drought.

Mitch Tuinstra, a professor and Wickersham Chair in agronomy, is studying tropical varieties of corn to understand which genes allow the plants to survive in hot, dry weather. The objective is to find ways to integrate those genes into corn that is bred to produce high yields in the Midwest.

"There are all these other genes out there in these tropical gene pools. We are looking for those genes that enhance the adaptability of temperate maize," Tuinstra said.

Mike Mickelbart, an associate professor of horticulture, studies something similar to drought tolerance - water-use efficiency. The goal is to get the highest yields in corn using the least amount of water.

"Our ultimate goal would be to provide plant breeders with genetic markers for water-use efficiency so they can incorporate this trait into their breeding programs," Mickelbart said.

He said there are genes in corn that affect transpiration, a process in which pores called stomata open and close on a leaf surface and allow water to escape, like sweat on a person. His research is aimed at finding variations in those genes that affect the ability of a plant to use water as efficiently as possible.

Tony Vyn, a professor of agronomy, is evaluating drought-tolerant corn hybrids developed in the private sector. He is comparing their performance against conventional hybrids in different stress situations, including high plant density and situations in which nutrients are limited.

A major part of Vyn's research involves determining whether optimum management practices for so-called drought-tolerant hybrids are different than for conventional hybrids currently in fields.

"It really has to be the integration of genetics and best management practices so that we can get the most corn per gallon of water and per ounce of nutrient," he said.

The Purdue Center for Global Food Security focuses on education, research and development, and advocacy efforts to find solutions to world hunger. The center recently received a $5 million grant from the Bill & Melinda Gates Foundation to study ways to control the Striga weed, which infests sorghum and other crops in Africa.

Center director Gebisa Ejeta, a distinguished professor of agronomy and 2009 World Food Prize laureate, is leading the research effort aimed at improving Striga-resistant sorghum that can tolerate drought conditions, said Gary Burniske, the center's managing director. Ejeta and others are testing plants this year in field plots.

"We're looking for an increase in yield under droughty conditions in different types of soils with different nutrient availabilities," Burniske said. "It also has to be resistant to Striga, which is a terrible problem in Africa."