The effectiveness of grafting to improve drought tolerance in tomato

Drought is a common stress in crop growth that limits plant growth, development and yield. Therefore, we explored the feasibility of bio-saving water for tomato production by grafting with drought-tolerant seedlings. In this experiment, we carried out grafting on different drought-tolerant tomato seedlings to study the effects of grafting on root growth and plant nutrient uptake under drought stress. We measured the effects of grafting on root growth, nutrient uptake, carbohydrate content and organic acids in tomato leaves and roots under drought stress. The growth and vigor of roots as well as the concentration of N, P, K, Ca and Mg of the plant were significantly inhibited by drought. The nutrient content was significantly decreased in leaves, and the content of carbohydrates and organic acids was increased in both leaves and roots under drought conditions. Treatment with drought-tolerant tomato seedlings significantly enhanced root growth and increased the element content under water deficit conditions compared to those grafted with drought-susceptible seedlings. In the plants grafted with drought-tolerant seedlings, the contents of carbohydrates and organic acids increased. Our results indicated that the grafted tomato seedlings showed beneficial root growth because drought-tolerant seedlings increased in inorganic and organic osmotic adjustment substances that helped the plants absorb more water and promoted plant growth.