Effect of grafting on yield and quality of eggplant (Solanum melongena L.)

Environmental conditions and growing techniques may influence the characteristics of eggplant fruits and their content in phenolic compounds. Grafting is a non chemical alternative for overcoming the effects of intensive and continuous cropping that can modify plant and fruit characteristics. The rootstocks preferred for eggplant are hybrids of tomato or tomato KVFN. Also species taxonomically close, as Solanum torvum, have been used and showed good vigour, compatibility and resistance to wilt disease. Information on yield and quality of grafted eggplants onto this rootstock is conflicting. Therefore, the aim of this study was to evaluate yield and quality of eggplant cultivars (Birgah, Black Bell, Black Moon and Longo) grafted or ungrafted onto Solanum torvum. Plants were grown from October 2009 to May 2010 in an unheated plastic greenhouse on solarized soil. Grafted plants had lower mortality, while yield and quality of fruits were mostly influenced by cultivars. The differences recorded for growth and yield of the tested cultivars might be due to different growth characteristics, graft affinity and compatibility. Longo and Black Moon were not influenced by grafting, while grafted plants of Birgah and Black Bell had a higher unmarketable production. Grafting onto Solanum torvum changed the color of fruits that were darker and with a less vivid color. Browning of inner tissue was not influenced by grafting. Total phenolic content was greater in the ungrafted plants. (C) 2012 Elsevier B.V. All rights reserved.