Yields of sesame vary dramatically under rain-fed conditions on marginal lands in Thailand

Abstract

The objectives of this research were to evaluate grain yield, related traits and some agronomic performances of 15 sesame cultivars under rain-fed conditions on marginal land of Northeast in Thailand. The experiments were conducted at two locations; Maha Sarakham and Buriram provinces in Northeast Thailand during the summer of 2018. The fields were arranged in a RCBD with 4 replications and 15 sesame cultivars. Significant differences were observed for all traits at both locations except SPAD chlorophyll meter reading (SCMR) at 90 DAP in Maha Sarakham. Significant differences were found between locations for yield and some of the yield components. It appeared that pod/plant, plant height, number of branches, and plant biomass were the most important components attributing to yield. Harvest index was negatively correlated with yield. Heritability estimates were the highest for plant height (0.88), branches per plant (0.92), pod width (0.95), and pod length (0.89). At Maha Sarakahm, cv. UB3 had the greatest grain yield (1058.03 kg ha-1), and was among the highest for number of branches/plant, plant height, and number of pods/plant, whereas KKU1 had the highest harvest index (43.62%). Mahasarakham60 had the highest SCMR value at 60 and 75 DAP and also total chlorophyll content at 60, 75 and 90 DAP. At Buriram cv. Buriram had the highest number of branches/plant, plant height, SCMR, total chlorophyll content, and number of capsules/plant, but did not have a high grain yield (334.44 kg ha-1). UB1 had the highest grain yield (545.63 kg ha-1) at Buriram. Environmental factors affected agronomic performances and grain yield in sesame grown under the rain-fed condition and marginal land in Thailand. If breeding under various environmental conditions, traits such as plant height and number of branches per plant would achieve the highest gains.