Investigation agronomic, physiological and molecular mechanisms of three capsule and single capsule feature in sesame plant (sesamum indicum l.)

This study was conducted with three capsule (Arslanbey) and single capsule (Hatipoğlu) sesame cultivars in field of the Faculty of Agriculture Siirt University in 2017 and 2018, to determine the agronomic, physiological and molecular mechanisms underlying the three capsule and single capsule phenomena in sesame plants. Agronomic (plant height, first branch height, number of branches, number of capsules per plant, 1000 seed weight and yield), physiological (oil - protein content, sesamol content, iron chelation, DPPH, and FRAP antioxidant activities, expression levels of catalase and peroxidase enzyme activities, sugar content, phenolic acids, and plant nutrient contents), and molecular (qRT - PCR (Concurrent) of the genes that are effective in flower formation, APETALA1, APETALA2, SPL4, SOC1, AT4G37770, SILPT3, and Beta-glucosidase genes) characteristics of the sesame cultivars used in the study were evaluated. These parameters were obtained by examining the seed and leaf tissues of sesame cultivars. Seeds obtained in 2017 and 2018 were used in seed tissue analysis. Leaf samples were collected from the plants based on flowering times for 9 weeks (one week before flowering, at flower initiation, and 1st to 7th weeks after flowering started) in the experiment established in 2018. As a result of the study, Arslanbey cultivar, which has mostly three capsules, had the highest values in both years for the agronomic parameters. The highest fat content was obtained in 2018 on Hatipoğlu, which has single capsule. While phenolic gallic acid was dominant in terms of phenolic organic acid values in all samples, it was followed by chlorogenic, vanillic, caffeic acid and hydroxy-benzoic acids, respectively. Oleic and linoleic acids had the highest proportion in terms of fatty acid. The oleic acid ratio was obtained between 40.19- 44.68%. Based on varieties, the highest oleic and linoleic ratio was obtained from the single-capsuled sesame variety. In terms of sugar content, the order was sucrose, fructose, glucose, and maltose in 2017; and sucrose, glucose, fructose, and maltose in 2018. The highest sesamol content was obtained from the three capsule cultivar. Leaf and seed tissues were evaluated separately in terms of protein content. Protein ratios in seed tissues ranged from 18.43% to 20.07%. Protein ratios in leaf tissues were between 13.4-15.12% in cultivars, and between 8.44-18.55% in terms of weeks. According to the results of metal- iron chelation, FRAP and DPPH antioxidant analysis in leaf tissues, the highest value was obtained from the single capsule cultivar. The highest values on the catalase and peroxidase enzymes as the enzyme activity in leaf tissues were obtained from the three capsule cultivar. As a result of the analysis of nutrient elements in leaf tissues, Ag, Al, B, Ba, Co, Cr, Li, Mg, Na, Ni, Pb, and Se were found to be high in the single capsule cultivar. Nutrient elements of As, Ca, Cd, Cu, Fe, K, Mn, Na, P, Sr, and Zn were found high in three capsule cultivar. According to the result of gene expression analyses of leaf tissues collected from cultivars for 9 weeks for to the capsule status; AP1, AP2, SPL4, SILPT3, Beta-glucosidase genes had the highest expression levels at ÇŞ6H-H (6th week after flowering) in single capsule cultivar, whereas in SOC1 and AT4G37770 genes had the highest expression levels at ÇS7H-H (7th week after flowering) in single capsule cultivar. It is thought that the agronomic, physiological and molecular results obtained from tis study will lead to the breeding and molecular studies for the formation of multi-encapsulation in sesame and similar plants in the future.