Sesame is a highly valuable crop with significant global importance due to its nutritional and economic value. To better understand the genetic diversity of sesame genotypes at both molecular and morphological levels, a comprehensive study was conducted using 25 pairs of simple sequence repeat (SSR) primers and 56 biological traits in a collection of 183 sesame accessions, which comprised 101 Chinese cultivars, 62 landraces, and 20 exotic accessions. The analysis revealed a total of 166 SSR polymorphic bands, with an average of 6.64 bands per marker. The values of Shannon’s information index ranged from 0.2732 to 0.6497, indicating a moderate level of genetic diversity. The polymorphic information index ranged from 0.0859 to 0.6357, further supporting the presence of genetic variation. The average frequency of heterozygous genotypes was calculated as 0.34, suggesting a relatively narrow genetic diversity. The application of the unweighted pair group method with arithmetic averaging (UPGMA) clustering and principal component analysis allowed for the categorization of the 183 sesame accessions into three distinct groups. Furthermore, the genetic diversity coefficient of sesame germplasm is generally constrained, with no significant difference observed between the genetic diversity coefficient of Chinese cultivars and that of foreign resources. The results provide valuable data for various applications, including the breeding and promotion of new sesame cultivars in China, the protection of new variety rights, the inquiry and identification of DNA genetic information of cultivars, as well as the development and utilization of sesame germplasm resources both domestically and internationally.

Sesame is a great reservoir of bioactive constituents and unique antioxidant components. It is widely used for its nutritional and medicinal value. The expanding demand for sesame seeds is putting pressure on sesame breeders to develop high-yielding varieties. A hybrid breeding strategy based on male sterility is one of the most effective ways to increase the crop yield. To date, little is known about the genes and mechanism underlying sesame male fertility. Therefore, studies are being conducted to identify and functionally characterize key candidate genes involved in sesame pollen development. Polyketide synthases (PKSs) are critical enzymes involved in the biosynthesis of sporopollenin, the primary component of pollen exine. Their in planta functions are being investigated for applications in crop breeding. In this study, we cloned the sesame POLYKETIDE SYNTHASE A (SiPKSA) and examined its function in male sterility. SiPKSA was specifically expressed in sesame flower buds, and its expression was significantly higher in sterile sesame anthers than in fertile anthers during the tetrad and microspore development stages. Furthermore, overexpression of SiPKSA in Arabidopsis caused male sterility in transgenic plants. Ultrastructural observation showed that the pollen grains of SiPKSA-overexpressing plants contained few cytoplasmic inclusions and exhibited an abnormal pollen wall structure, with a thicker exine layer compared to the wild type. In agreement with this, the expression of a set of sporopollenin biosynthesis-related genes and the contents of their fatty acids and phenolics were significantly altered in anthers of SiPKSA-overexpressing plants compared with wild type during anther development. These findings highlighted that overexpression of SiPKSA in Arabidopsis might cause male sterility through defective pollen wall formation. Moreover, they suggested that SiPKSA modulates vibrant pollen development via sporopollenin biosynthesis, and a defect in its regulation may induce male sterility. Therefore, genetic manipulation of SiPKSA might promote hybrid breeding in sesame and other crop species.

B vitamins are essential micronutrients for human health with prominent antioxidant properties, capable of scavenging reactive oxygen species (ROS) and maintaining redox homeostasis, protecting cells from oxidative damage. To address global nutrient deficiencies and identify plant-based antioxidant sources, this study quantified seven B vitamins (B₁, B₂, B₃, B₅, B₆, B₉, B₁₂) in seeds, leaves, and seedlings of five oilseeds (sesame, peanut, soybean, rapeseed, perilla) and two leafy vegetables (spinach, lettuce) via LC-MS/MS, revealing distinct species- and tissue-specific patterns. Notably, sesame seeds exhibited exceptional vitamin B₃ (niacin, 39.3 μg/g), surpassing other oilseeds by 1.6-8.2-fold; its leaves contained outstanding vitamin B₆ (2.88 μg/g), with 2.57–8.31-fold higher than spinach (1.12 μg/g) and lettuce (0.34μg/g), whereas, vitamin B₁₂ (0.44 μg/g), with levels of ~13–20 times higher than other leaves samples. Sesame seedlings recorded high vitamin B₆ (1.6 μg/g) and B₁₂ (0.1 μg/g) among the oilseed crops seedlings. These findings highlight sesame as a multifunctional B vitamin resource for antioxidant nutrition, supporting dietary optimization, crop biofortification, and mitigation of global B vitamin inadequacies via plant-based solutions.

B vitamins are essential micronutrients for human health with prominent antioxidant properties, capable of scavenging reactive oxygen species (ROS) and maintaining redox homeostasis, protecting cells from oxidative damage. To address global nutrient deficiencies and identify plant-based antioxidant sources, this study quantified seven B vitamins (B₁, B₂, B₃, B₅, B₆, B₉, B₁₂) in seeds, leaves, and seedlings of five oilseeds (sesame, peanut, soybean, rapeseed, perilla) and two leafy vegetables (spinach, lettuce) via LC-MS/MS, revealing distinct species- and tissue-specific patterns. Notably, sesame seeds exhibited exceptional vitamin B₃ (niacin, 39.3 μg/g), surpassing other oilseeds1.6–8.2-fold; its leaves contained outstanding vitamin B₆ (2.88 μg/g), 2.57–8.31-fold higher than spinach (1.12 μg/g) and lettuce (0.34 μg/g), and vitamin B₁₂ (0.44 μg/g) levels ~13–20 times higher than other leaf samples. Sesame seedlings recorded high vitamin B₆ (1.6 μg/g) and B₁₂ (0.1 μg/g) among the oilseed crops seedlings. These findings highlight sesame as a multifunctional B vitamin resource for antioxidant nutrition, supporting dietary optimization, crop biofortification, and mitigation of global B vitamin inadequacies via plant-based solutions.

Sesame is a significant oilseed crop whose exceptional oxidative stability is closely associated with its abundant endogenous antioxidants. As one of the most predominant lipid-soluble antioxidants in sesame, vitamin E (VE) plays a critical role in scavenging lipid peroxyl radicals, terminating lipid peroxidation chain reactions, and protecting cellular membranes from oxidative damage, thereby maintaining intracellular redox homeostasis and attenuating the development of oxidative stress-related disorders. Although VE is a potent natural antioxidant with significant pharmacological activities in mitigating oxidative stress-related disorders, the genetic mechanisms underlying the natural variation in VE content in sesame remain incompletely understood. Here, variation in VE content was evaluated across 400 sesame accessions grown in two environments. Ultra-high-performance liquid chromatography (UHPLC) analysis revealed that only γ-tocopherol was detected in sesame seeds, with concentrations between 169.33 and 463.31 mg/kg, averaging 316.28 mg/kg. The newly acquired SNP and InDel data from whole-genome resequencing were associated with the phenotypic data, leading to the identification of five significant loci associated with VE content. Comparative transcriptomic profiling of two sesame accessions with distinct VE contents revealed the differential expression of key biosynthetic enzyme genes (such as GGDR, PDS1, VTE2, and VTE4) between the two accessions. By integrating a genome-wide association study with transcriptomic data, two primary candidate effector genes, SINPZ1100015/SiNST1 and SINPZ0901927, were identified, with SiNST1 being particularly prominent. Functional validation further showed that overexpression of SiNST1 in the hairy root of sesame significantly decreased VE content. This investigation advances the comprehension of variations in VE content and the regulatory mechanisms governing its biosynthetic metabolism in sesame, supporting the development of functional sesame varieties for dietary antioxidant supplementation.