Cucumber (Cucumis sativus L.) is a genetically diverse group of vegetables with various cultivars having distinct traits. This study optimized somatic embryogenesis in anther-derived calli of selected commercial cucumber cultivars (Local Khera, Champion, and CP 001). Therefore, the experiment investigated the impact of 2,4-D and benzyl 6-aminopurine (BAP) treatments on embryo formation. The anthers collected from different-sized floral buds sustained culturing in various concentrations of 2,4-D and BAP (0, 0.5, 1, 1.5, 2, 3, and 4 mg L^-1). It was evident that calli induction in cucumber cultivars received significant stimuli from 2,4-D and BAP concentrations and dark culture conditions during calli culture. The maximum calli induction (51%) was prominent in anthers of cv. CP 001 at a higher level of 2,4-D in small-sized floral buds. However, the anthers of cucumber cultivar Local Khera (59.72%) performed better for calli induction than Champion (57.14%) and CP 001 (51.43%). The highest embryogenesis appeared in anther-derived calli of cultivar Local Khera (12%) under light culture conditions in tiny flower buds. Meanwhile, maximum (8%) embryo formation observed at a higher level of 2,4-D (4 mg L^-1) resulted in cultivars Champion and CP 001 under dark conditions. In conclusion, from the tested treatments, applying the highest level of 2,4-D and BAP at 4 mg L^-1 was more effective than other treatments, including the control. However, more calli induction was noteworthy under dark culture conditions, and maximum embryo formation occurred under light culture conditions.

Keywords: Cucumber (C. sativus L.), cultivars, anthers, dark, light, calli, embryo

Key findings: Applying the highest level of 2,4-D and BAP at 4.0 mg L^-1 was the most effective for calli production and embryogenesis in cucumber (C. sativus L.). However, more calli induction was prominent under dark culture conditions, while maximum embryo formation occurred under light culture conditions.