Location: Crop Genetics and Breeding ResearchTitle: Association of nitrogen fixation to water use efficiency and yield traits of peanut Author
Submitted to: Journal of Plant Production Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/1/2013
Publication Date: 12/20/2013
Citation: Pimratch, S., Jogloy, S., Vorasoot, N., Toomsan, B., Kesmala, T., Patanothai, A., Holbrook Jr, C.C. 2013. Association of nitrogen fixation to water use efficiency and yield traits of peanut. Journal of Plant Production Science. 7:225-242. Interpretive Summary: Improvement of drought tolerance in peanut would greatly benefit farmers in rainfed regions where drought is a major constraint limiting yield and quality. The objective of this study was to determine if improvement in nitrogen fixation might be an effective strategy for breeding peanut for high yield under drought stress conditions. Twelve peanut genotypes were tested under three irrigation regimes. Results indicated that nitrogen fixation under drought conditions contributed to vegetative growth and water use efficiency rather than to pod yield. Selection for high nitrogen fixation in peanut could lead to high biomass production and water use efficiency, but may not improve pod yield under drought conditions.
Technical Abstract: Improvement of N2 fixation might be an effective strategy in peanut breeding for high yield under drought stress conditions. However, under water limited conditions peanut varieties having high water-use efficiency (WUE) are favorable. A pot experiment was conducted under greenhouse conditions at Khon Kaen University, Thailand during December 2002 to May 2003, and repeated during June 2003 to November 2003. Twelve peanut genotype were tested under three water regimes to estimate the relationships between N2 fixed with biomass production, WUE and pod yield under drought stress conditions. N2 fixed, biomass production, pod yield and WUE were reduced by drought stress. At 2/3 AW, Tifton-8 and KK 60-3 were the best genotypes for high N2 fixed and high WUE. ICGV 98324 and ICGV 98300 had high pod yield, whereas Tifton-8 had low pod yield. N2 fixed was positively correlated with biomass and WUE under mild drought conditions but negatively correlated with pod yield. Tifton-8 was the best genotype for N2 fixed and WUE, but it was a poor performer for pod yield under drought conditions. ICGV 98324 and ICGV 98300 had higher pod yield with lower N2 fixed and WUE than did Tifton-8. Results indicated that N2 fixed under drought conditions contributed to vegetative growth and water use efficiency rather than to pod yield. Improvement for high N2 fixed in peanut could lead to high biomass production and WUE but may not necessarily improve pod yield under drought stress conditions.