Effect of grafting on vegetative parameters of tomato and induction of resistance against Tuta absoluta (Meyrick) (Lep.: Gelechiidae)

In this study, the effect of grafting of tomato on eggplant rootstock were investigated on growth indices of the tomato plant and biological parameters of Tuta absoluta (Meyrick) (Lep.: Gelechiidae). In order to evaluate of fertility and fecundity, a pair of adult insects (male and female) of T. absoluta, with less than 24 h age, were kept on each plant (grafted and non-grafted). Then, one egg (in 15 replications) was placed on each plant to measure the developmental period of embryonic, larval and papal stages until adult insect emergence. Seventy-five days after grafting, except the stem diameter, all growth indices of grafted plants including plant height, number of nodes and leaves were significantly higher than non-grafted plants. Also, weight of fresh and dry root of grafted plants were higher compare to non-grafted plants. Larval and pupal developmental period of T. absoluta fed on grafted plants were significantly higher than non-grafted plants. Besides, the mean fecundity of the adult female of T. absoluta was lower on grafted plants. Amount of total phenol content in different days after infestation with T. absoluta indicated a significant increase in grafted plant. Results of this research clearly showed that the grafting of tomato plants on eggplant rootstocks could be an effective approach for increasing of plant growth and subsequently its resistance to T. absoluta.