Effects of Cytokinin on Physiological and Biochemical Indicators of Some Tomato Varieties ( Solanum lycopersicum L.) Cultivated in Vietnam

Tomato (Solanum lycopersicum L.) is widely cultivated and consumed in many countries around the world, including Vietnam. Cytokinin (CK) is a plant hormone that plays a crucial role in numerous plant growth and developmental processes. A study was carried out to analyze the impacts of 6-benzyl adenine (6-BA, a type of CK) on some physiological and biochemical parameters of tomato varieties at the 5-leaf stage and the flowering stage cultivated in Thanh Hoa province, Vietnam. The experiments consisted of two factors (6-BA concentration and tomato variety) arranged in a Split Plot design with three replications, in which the concentration of 6-BA (0 (control), 6 and 12 mg L-1) was the whole-plot factor and the tomato variety (P375, CS1, Pn and F) was the split-plot factor. The results showed that indicators including plant height, dry matter content, chlorophyll a content, chlorophyll b content, total chlorophyll content, carotenoid content, vitamin C content, total organic acid content, catalase enzyme activity and peroxidase enzyme activity of tomato varieties treated with 6-BA at a concentration of 6 and 12 mg L-1 were higher than those of the control group. The study also showed that impacts of 6-BA on tomato physiological and biochemical parameters depend not only on the concentration of 6-BA but also on the developmental stages and plant varieties. In general, CK has markedly influenced the physiological and biochemical parameters of tomato varieties. These results provide some insights into the role of CK in tomato growth and development.