As anyone in South Louisiana knows, rice is a major part of one’s diet. It is the most widely consumed staple food for more than half of the world’s population, which continues to grow each year. With the production of rice increasing, so does the need for water to grow it. In order to not use up nature’s most precious valuable resource — water — one LSU College of Engineering professor is working with the LSU AgCenter to design a new variety of rice that will be able to withstand drought conditions, making rice production fruitful while not exhausting natural resources.
Thanks to a $10 million grant from the U.S. Department of Agriculture’s National Institute of Food and Agriculture sector, LSU Mechanical Engineering Associate Professor Manas Gartia is collaborating with a team of 24 researchers spanning five states under the leadership of Professor Prasanta Subudhi of LSU’s AgCenter School of Plant, Environmental, and Soil Sciences to develop the new type of rice.
“Over the last 40 years, land-use efficiency for U.S. rice has increased by 39% while water and energy use, greenhouse gas emissions (GHG), and soil losses have declined by 28% to 52%,” Gartia said. “Nonetheless, many of the rice production practices used in the U.S. are still resource-intensive.”
According to Gartia, the season-long flood irrigation used in rice production contributes to the reduction in the underground water table, increased groundwater salinity, contamination of air and water, and GHG emission.
“The U.S. rice industry has set ambitious goals of increasing land-use efficiency by 10% and reducing water and energy use, GHG emissions, and soil losses by 8% to 13% by 2030,” he said. “This proposal is developed to accomplish these sustainability goals in the U.S. rice production system and is based on two hypotheses.”
The first theory is that the sustainability and profitability of rice production systems can be enhanced by developing new rice varieties with better adaptation to climate variabilities and by implementing innovative crop management practices. The second theory is that implementing education and outreach Extension programs will expedite the adoption of a climate-resilient rice management system by both current and future generations of rice growers in the southern U.S.
Gartia’s role in the project will deal with the first hypothesis. He will study the phenotype and molecular changes in rice due to various stresses such as salt, drought, water, and heat and identify the genes responsible for that behavior.
“Once we are able to identify the genes responsible for the rice plant’s survival under drought conditions, we can create a variety of rice with that particular trait and grow it under drought conditions,” Gartia said.
The leaf metabolic profiling in stress-tolerant plants will be examined by combining innovative metabolomic (NMR, LC-MS) and imaging (Raman microscopy) technologies. Gartia’s goal is to determine whether Raman microscopy can be applied to accurately assess abiotic stress levels in both genetically diverse and near-isogenic rice lines that differ in their stress-tolerance levels.
“Raman mapping will be employed to observe dynamic fluctuations in metabolite levels in real time, aiming to establish a potential correlation between these metabolites and the stress-tolerance levels of various rice genotypes under different stress conditions,” Gartia said.
“Further, LC-MS and NMR will be used to perform metabolite characterization of the leaf sample. Mass Spectrometry Imaging (MALDI) and mass spectrometry coupled with liquid chromatography (LC-MS) will be used to determine the lipidomic profile changes in the leaf due to the environmental stressor. These complementary techniques will be used for metabolomic characterization of one mapping population each for drought and salinity stress.”
Gartia’s work on this project will have huge implications for one of the biggest industries in the country and state. The U.S. is the world’s fifth-largest exporter of rice, having produced more than 150 million pounds of the tiny white substance in 2022. Louisiana is the nation’s third-largest rice-producing state behind Arkansas and California, thanks to its warm climate, abundant water, and water-retaining clay soils.