Location: National Peanut Research Laboratory
Project Number: 6044-21000-005-03-R
Project Type: Reimbursable Cooperative Agreement
Start Date: Oct 1, 2017
End Date: Apr 30, 2020
Develop near-term solutions that can be implemented by peanut producers to mitigate drought; improve water use efficiency and improve environmental footprint of peanut production. The research involves an integrated approach to developing peanut cultivars or germplasm lines with resistance to drought stresses and also seeks to elucidate the underlying mechanisms of drought response. The objectives of the proposal are to: 1) characterize physiological and molecular traits of the U.S. peanut mini-core collection and select breeding lines for identification of drought tolerant genotypes; 2) identify key molecular and biochemical components of drought response regulation system(s) in peanut; and 3) develop irrigation schemes that enhance water use efficacy, complement nutrient acquisition, maintain or improve yield and quality with the best economic returns for drought tolerance cultivars/breeding lines.
1) To characterize physiological and molecular traits for peanut drought tolerance, the U.S. peanut mini-core collection and select breeding lines will be grown under environmental control small plots located at National Peanut Research Laboratory (NPRL), Dawson, Georgia. Plants will be subjected to drought during growing season. Physiological measurements, such as relative water content (RWC) and specific leaf area (SLA), will be conducted of drought and control plants. Leaf samples will also be collected and frozen for ribonucleic acid (RNA) isolation. Yield and grade data will be collected at the end of the growing season and all data will be analyzed to identify drought tolerant/resistant peanuts. 2) To identify key molecular and biochemical components of drought response regulation, RNA will be extracted from frozen leaf sample from drought tolerant and susceptible peanut genotypes. Transcriptomes and small RNA sequencing information will be generated and analyzed. From this set of sequencing data, candidate genes will be selected for real-time polymerase chain reaction (PCR) analyses to associate drought regulated gene-expression. Drought regulated genes will be utilized to select new peanut lines with drought tolerance. 3) To develop irrigation schemes that can maintain or increase peanut production, peanut genotypes will be subjected to variable irrigation levels (full irrigation of peanut is recommended by IrrigatorPro software that was developed at NPRL for farmers): 100%, 75% and 50% at several locations. Combination of irrigation treatments, genotypes, and locations that result in the best production levels as well as the most consistent result will help farmers select the best combination of genotype and environment for highest peanut production.