Submitted to: Aflatoxin Elimination Workshop Proceedings
Publication Type: Abstract Only
Publication Acceptance Date: 10/1/2002
Publication Date: 12/1/2002
Citation: Dong, W., C. C. Holbrook Jr, B. Guo, M. Luo, D. M. Wilson, C. K. Kvien, D. Rowland. 2002. Evaluation of physiological measures of drought stress to indirectly select for reduced aflatoxin contamination in peanut. Proc. Aflatoxin Elimination Workshop p. 145. Interpretive Summary: not required
Technical Abstract: Developing and utilizing resistant cultivars is a prospective way to reduce or eliminate preharvest aflatoxin contamination in peanut (Arachis hypogaea). Indirect selection tools would aid in the development of peanut cultivars with resistance to aflatoxin contamination. The objectives of this study were to examine the relationships between visual drought stress rating, SPAD chlorophyll meter reading (SCMR) and aflatoxin contamination in a range of peanut, and to evaluate the possibility of using physiological measures of drought stress to indirectly select for reduced aflatoxin contamination in peanut. Ten peanut genotypes were selected for the experiment conducted in Tifton, GA. Drought and heat stress conditions were imposed by covering the entire test plots with a mobile greenhouse. Significant differences of SCMR and visual drought stress ratings were observed among the genotypes. Five breeding lines showed lower drought stress ratings than the drought tolerant line Tifton8, and three of them had a very low aflatoxin contamination in 2001. Gk7HO/L, which had high aflatoxin contamination in 2001, showed the highest drought stress in this experiment. The results indicated that visual drought stress rating was a steady trait in peanut. No significant correlations between SCMRs and drought stresses were found. We are conducting more research to determine the correlation between SCMR and drought tolerance, and between SCMR and aflatoxin contamination in peanut.