ABIOTIC STRESS TOLERANCE
Rows of peanuts grown under full irrigation (left), 50% ET replacment (center), or 25% ET replacement (right).
Punched leaf disks of peanut accessions tested for heat stress tolerance by the acquired theromotolerance assay.
Our long-term goal is the development of improved varieties that can be grown profitably under deficit irrigation or heat stress.
• Water deficit stress. Adaptive mechanisms to drought include enhanced water use efficiency (WUE), transpiration efficiency (TE), reduced transpiration (T), capacity for continued flowering during drought, high harvest index (HI), and paraheliotropism.
We have screened germplasm from several sources under water deficit stress, and have found some accessions with improved tolerance to water deficit, based on plant response in the field (paraheliotropism, SPAD chlorophyll, and flowering), as well as measured by yield and harvest index. Genotypes with favorable responses to each drought-adaptive mechanism have been identified in these studies. We are using several of the best accessions to cross to cultivated materials, and are evaluating populations in the field.
• Heat tolerance. Using the acquired thermo-tolerance assay, we have found that there are some peanut accessions that have greater ability to adapt to heat stress. We have expanded the initial screen, and hope to identify additional accessions.
Qiu, H., Q. Gu, S. Kuppu, L. Sun, X. Zhu, N. Mishra, R. Hu, G. Shen, J. Zhang, Y. Zhang, L. Zhu, X. Zhang, M. Burow, P. Payton, and H. Zhang. (2013) Expression of the Arabidopsis vacuolar H+-pyrophosphatase gene AVP1 in peanut to improve drought and salt tolerance. Plant Biotechnol Rep. 7:345–355.
Rowland, D., N. Puppala, J. Beasley Jr., M. Burow, D. Gorbet, D. Jordan, H. Melouk, C. Simpson, J. Bostick, and J. Ferrell. (2012) Variation in carbon isotope ratio and its relation to other traits in peanut breeding lines and cultivars from U.S. trials. J. Plant Breed. Crop Sci. 4:144-155.
Gomez S., M., G. Burow, J. J. Burke, V. Belamkar, N. Puppala and M. D. Burow. (2011) Heat stress screening of peanut (Arachis hypogaea L.) seedlings for acquired thermotolerance. Plant Growth Regulation 65: 83-91.
Qin, H, Q. Gu, J. Zhang, L. Sun, S. Kuppu, Y. Zhang, M. Burow, P. Payton, E. Blumwald, and H. Zhang. (2011) Regulated expression of an isopentenyltransferase gene (IPT) in peanut significantly improves drought tolerance and increases yield under field conditions. Plant Cell Physiol. 52:1904-14.
Kottapalli, K. R., R. Rakwal, J. Shibato, G. Burow, D. Tissue, J. Burke, N. Puppala, M. Burow, and P. Payton. (2009) Physiology and proteomics of the water-deficit stress response in three contrasting peanut genotypes. Plant, Cell, and Envir. 32: 380-407.