Oil Content and Composition of Sesame (Sesamum indicum L.) Genotypes as Affected by Irrigation Regimes

Abstract

AbstractThe fatty acid composition of sesame seed oil determines its commercial value, and drought stress and genotype may affect both the quality and quantity of oil that is extractable by sesame seed processors. Therefore, this experiment was conducted in a field located in Isfahan, Iran, to determine the effect of three irrigation regimes [55 % (I1, as control), 75 % (I2) and 85 % (I3) of depletion of soil available water] on the oil content and composition of ten sesame genotypes (Isfahan4, Shahreza, Borazjan, Ahvaz, Kal, Shiraz, Markazi, Ardestan, Ultan and Isfahan1). Seed oil content and palmitic, linoleic, linolenic, stearic and oleic acid contents were determined during 2010–2012. Shahreza under I1, Shahreza and Ardestan under I2 and Isfanahan4 under I3 irrigation regimes produced the highest oil content, while Kal under I1 and I2 and Isfahan4 under I3 irrigation regimes produced the highest oil yield. Ultan had the lowest palmitic acid content under all three irrigation regimes, while Isfahan4 had the highest reduction in palmitic acid content under I2 and I3. Borazjan produced the lowest stearic and highest linoleic acid contents under the I1, I2 and I3 irrigation regimes. Kal, Kal and Ardestan, and Ardestan and Isfahan1 produced the highest oleic acid under I1, I2 and I3, respectively. Shahreza under I1 and I2 and Isfahan4 under I3 had the highest linolenic acid content. The results showed that the sesame oil content and composition were genotype‐drought level specific, and based on oil yield production and percent reduction in saturated and increase in unsaturated fatty acid contents, Isfahan4 was the most drought‐tolerant genotype.