Photoperiod effects on seed quality traits in peanut

Peanut (Arachis hypogaea L.) is a rich source of oil, protein, minerals, an d vitamins. The chemical and physical seed quality aspects are gaining impo rtance because of increased use of peanut as a food crop; however, little o r no investigation has been carried out on the effect of photoperiod on the se traits. The objective of this study was to determine the effect of photo period on seed quality traits. The experiment was conducted for three seaso ns in a three replicate split-plot randomized complete block design with th ree photoperiods (ND = Normal day, 12 h; SD = Short day, 8 h; LD = Long day , 16 h) as main plots and 10 genotypes as subplots. The SD and LD condition s were created artificially. Pooled analysis of variance, based on a mixed linear model with season (S) as random and photoperiod (Ph) and genotype (G ) as fixed effects, indicated significant S and G differences for most of t he traits studied. Ph differences were significant only for shelling percen tage and palmitic and eicosenoic fatty acids. The interactions S x Ph, S x G, Ph x G, and S x Ph x G were significant for several traits. When SD and LD treatments were compared with ND, shelling percentage increased under SD . Oil content, oleic (O) and linolenic (L) fatty acids, and On ratio were n ot affected due to variation in photoperiod. However, palmitic acid increas ed and eicosenoic acid decreased under SD. The SD conditions were more inte ractive with seasons and genotypes for fatty acids. High performing and pho toperiod insensitive genotypes were identified for various seed quality tra its. These genotypes would be useful in breeding programs aimed at developi ng high yielding genotypes with improved seed quality for edible purposes.