In Vitro Micrografting Protocol in Lycopersicon esculentum

Bacterial wilt caused by Ralstonia solanacearum, is the most important vascular disease among plants around the world. The bacteria lives in the soil where it can survive for more than ten years. It is found in all regions of Brazil, predominantly in areas with high humidity and temperature, and it attacks plants in the Solanaceae family. Micropropagation performed in association with micrografting provides a high rate of plant multiplication and disease free material. In addition, it provides information on grafting compatibilities. The present work studied micrografting of tissue cultured tomato (Lycopersicon esculentum Mill.). Scions were cleft-grafted onto rootstocks (Solanum palinacanthum) under aseptic conditions. Seeds of Solanum palinacanthum and Lycopersicon esculentum were placed in MS medium with different concentrations of salt (full strength, 1/2 strength, strength and. strength), with and without light. The experimental design was completely randomized in a factorial experiment 5 x 2, with four replicates per treatment. After 30 days, explant length and width were evaluated. Another experiment was performed to evaluate five different sucrose concentrations (0.0; 5.0; 10.0; 15.0; 20.0; 25.0; and 30.0 g L-1), with and without light. The experimental design was completely randomized in a factorial experiment 7 x 2, with five replicates per treatment. After 30 days, explant length and width were evaluated. Two methods of micrografting were used: Inverted T and Bisel cut method. MS medium containing. strength salts and 30 g L-1 sucrose was the best for micrografting and the inverted T method showed highest percentages of plant survival.