Yield Comparison of Sesame Cultivars and Their Physiological Growth Indices Under Chemical and Biological Potassium Fertilizer Applications

To compare the yield and physiological growth indices of three Iranian sesame cultivars under the application of chemical and biological potassium fertilizers a pot experiment was conducted in the summer of 2015 in greenhouse. This study was performed as factorial arrangement based on a randomized complete block design with three replications. The potassium fertilizer application, based on soil test, was in four levels (K1:K2SO4 50%, K2: Bacillus circulans L., K3: Bacillus megatherium L. and K4: KSB1⤠ and three sesame cultivars used were Ultan, Yekta and Dashtestan 2. The plant samples were taken from 30 to 105 days after sowing with 15 days intervals. LAI, TDM, CGR, NAR and RGR were measured during the different growth stages. The results showed that the Yekta cultivar produced the highest seed yield (18.62 g.plant-1). Ultan produced highest growth rate as compared to the other cultivars. Furthermore, it responded differently to the application of biologic KSB1 fertilizer as compared to the other treatments and cultivars. KSB1 improved and accelerated plant growth rate at 90 days after sowing. While, the use of chemical potassium sulfate, KSB2 and combined application of Bacillus circulans L. with KSB1 and 2 improved growth 105 days after sowing.