Location: Crop Genetics and Breeding ResearchTitle: Response of reproductive characters of drought resistant peanut genotypes to drought Author
Submitted to: Asian Journal of Plant Sciences
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 11/20/2009
Publication Date: 12/15/2009
Citation: Songsri, P., Jogloy, S., Kesmala, T., Vorasoot, N., Akkasaeng, C., Patanothai, A., Holbrook Jr, C.C. 2009. Response of reproductive characters of drought resistant peanut genotypes to drought. Asian Journal of Plant Sciences. 7(5):427-439. Interpretive Summary: Unpredictable rainfall creates conditions of drought stress which reduced the yield of peanut in areas throughout the World. Breeding peanut varieties with improved water use efficiency would help in alleviating this problem. The objectives of this study were to evaluate genetic variations in yield and reproductive developmental characters among peanut genotypes in response to drought and relate these responses to pod yield under different available soil water levels. Eleven peanut genotypes were evaluated in field studies using variable soil moisture levels. Data were recorded for pod yield and reproductive characters. Drought reduced pod yield, number of pegs and pods per plant. Some genotypes achieved high yield under drought stress due to their overall high yield potential, whereas others showed low reductions in yield under drought stress.
Technical Abstract: The aims of this study were to evaluate genetic variations in yield and reproductive developmental characteristics among peanut genotypes in response to drought and relate these responses to pod yield under different soil moisture. Eleven peanut genotypes were tested under three soil moisture levels [field capacity (FC), 2/3 available water (AW) and 1/3 A/W] in field experiments. Data were recorded for number of flowers, pegs (Rss), immature pods and mature pods per plant, seed per pod, 100-seed weight and pod yield at harvest. A drought tolerance index (DTI) for pod yield was calculated as the ratio of pod yield under stress treatment to that under well-watered conditions. The differences among water regimes were significant for pod yield, number of Rss, immature pods and mature pods per plant, seed per pod and 100 seed weight and differences among genotypes were significant for all traits. Drought reduced pod yield, number of Rss, pods and mature pods per plant. Early peak of flowering is important for the formation of mature pods under drought conditions. Two different strategies were used in maintaining high pod yield under drought. High yield potential was important for ICGV 98348 and ICGV 98353, whereas low pod yield reduction was important for ICGV 98305, ICGV 98303 and ICGV 98300. Tifton 8 showed the lowest pod yield and poor seed filling. High Rss and well-filled mature pods were the most important traits contributing to high pod yield in drought resistant genotypes.