Growth, yield and phenolic compounds in okra (Abelmoschus esculentus) with culture condition and germination of seeds elicited by gamma radiation

Okra (Abelmoschus esculentus L. Moench) is one of the most cultivated multipurpose crops and the sixth vegetable crop globally. In this study, the effects of different gamma-ray doses (0, 200, 400, 600, 800, 1000 Gy/h) on germination, plant growth, flowering, fruit yield characters, and fruit phytochemical profile under different culture conditions (in vitro-24 h dark, in vitro-12 h light/12 h dark, in vivo-field) were evaluated. The results showed gamma-rays at 800 Gy/h and 12 h light/12 h dark in vitro culture as the most advantageous strategy for fruit phytochemical profile (total phenolic content:60.8, catechin:13.8, rutin:11.9, isoquercitin:9.2, quercetin:11.9 mg/g dry weight, antioxidant activity:57.2%). Gamma radiation at 200 Gy/h and in vitro culture led to earlier fruit maturation (43.7-44.3 days) and a higher number of fruits (9-9.9), while earlier germination (5-5.5 days) and plant height (31.5-33.8 cm) promoted by 800 and 1000 Gy/h, respectively. Earlier flowering (40.5 days), fruit initiation (42.6 days), and higher fruit length (10.5 cm) were observed under 800 Gy and in vivo-field conditions, while a number of leaves (9.8) was highest at 200 Gy/h. Gamma radiation is an effective abiotic elicitor for more desirable trait plants, fruits of enhanced bioactive potential, and development of mutant varieties.