Research on dryland cropping systems to address future drought and hunger issues

Murali Darapuneni recalls stories about how difficult it was for his ancestors during times of drought conditions and famine in India in the early 1900s. “They had limited resources and research at that time,” he said. “My grandparents told me about those stories and how difficult it was to feed the people.”

Darapuneni is now an assistant professor of semi-arid cropping systems in the New Mexico State University College of Agricultural, Consumer and Environmental Sciences. Part of the Department of Plant and Environmental Sciences, he is researching efficient dryland cropping systems at the NMSU Agricultural Science Center at Tucumcari.

He studied at Acharya N. G. Ranga Agricultural University in India, where he earned a bachelor’s degree in horticulture. He has a master’s degree in plant, soil and environmental science from West Texas A&M University and a doctorate in agronomy from Texas A&M University.

Knowing the agricultural challenges his forefathers faced is the motivation behind Darapuneni’s research efforts in dryland cropping systems. “Things were very difficult for our ancestors, and with scientific advancements, I thought maybe I could contribute a little bit to agriculture by becoming an agricultural scientist,” he said.

Realizing that the projected world population is 10 billion by 2056, Darapuneni understands the importance of having enough crops to feed all the people on earth. He believes if researchers succeed in improving the yield potential of 40 percent of global land area under arid and semi-arid conditions, it will lead to a significant contribution to future food security.

He is searching for efficient, innovative cropping systems in the semi-arid conditions of Eastern New Mexico. His research may be applicable to most of the semi-arid environments in the Western United States and other global regions, where dryland conditions are predominant.

Cropping systems research is very complex in that it involves numerous factors, including, soil, water, environment, weather, marketing capabilities and farmer beliefs. “We need to design a cropping system that is resilient, sustainable, economically viable and should able to increase profitability for the producers,” Darapuneni said.

Darapuneni is focusing on both successful existing methods as well as new innovative practices. He is currently concentrating on several management practices at the science center in Tucumcari, including crop rotation, crop selection, cover cropping, tillage management systems and manure management. “All of these components are geared toward achieving the over-arching goal of improving the input use efficiency, especially the water use efficiency and nutrient use efficiency,” he said.

He is specifically researching the water use efficiency of 17 cover/rotation crops and determining what these crops yield with an incremental amount of given water throughout the season. “For example, if you have 16 inches of rainfall, you have to know how to design a cropping system for winter wheat, which takes about six to seven inches of the soil moisture before it produces its first pound of the grain,” he said.

“It’s really challenging, because with 16 inches of rainfall, how are we going to support two or three crops in the rotation?”

Darapuneni is working on a solution. One concept is the use of forage systems, due to their high water-use efficiency, compared to grain-based systems. This may be a viable option, as forage crops may be terminated at any time, considering the risk associated with the unpredictable nature of weather in these regions. Also, producers can feed the forage to their livestock. “We are lucky in New Mexico that we have the livestock component that can act in synergy to the forage cropping systems,” he said.

Another possibility to address the semi-arid cropping issue is manipulating the application of manure. “At Tucumcari, we are aimed at cutting the manure material, transportation and application costs by 60 percent by applying it to the strip-till area around the plant root zone,” he said. “Additionally, this will enhance the water and nutrient use efficiency.” Darapuneni also said chemistry should be further explored as a viable solution.

“One possible avenue that we haven’t exploited fully to solve the presumed food crisis in the near future is the chemistry,” he said. “One will be amazed at how far we’ve travelled, what great achievements we’ve accomplished and what we still can do in this particular area for the welfare of human race.

“Among other advancements in chemistry, there are two important efforts that may potentially solve the future food security problem: converting C3 species to C4 species and finding a way to produce usable water chemically in a massive quantity to support future agriculture. These efforts are going to be the most significant scientific achievements of the century if we succeed.” Whichever cropping system turns out to be the best method, Darapuneni’s goal is for it to have a positive economic impact.

“If we can make even a small yield improvement of $10 per acre – which is equivalent to about 1.5 bushels of wheat at $6.50 per bushel – through crop selection and careful rotation, while improving the water use efficiency and soil quality, it would produce a significant economic benefit of $3.8 million in value,” he said. No matter what the solution is to the semi-arid cropping challenge, Darapuneni hopes his research will address the issue of drought and hunger for future generations. “Hopefully I’ll do significant things here in agriculture,” he said. “Let’s hope so.”