Europ.J.Hort.Sci., 76 (2). S. 41–44, 2011, ISSN 1611-4426. © Verlag Eugen Ulmer KG, Stuttgart Europ.J.Hort.Sci. 2/2011 Role of Different Rootstocks on Yield and Resistance for Fusarium oxysporium, Verticillium dahliae and Meloidogyne incognita in Grafted Peppers N. Geboloğlu 1) , Y. Yanar 2) , D. Yanar 2) , F. Akyazı 3) and P. Çakmak 1) ( 1) Gaziosmanpaşa University Agricultural Faculty, Department Horticulture, Tokat, Turkey, 2) Gaziosman- paşa University Agricultural Faculty, Department Plant Protection, Tokat, Turkey and 3) Ordu University, Agricultural Faculty, Department Plant Protectection, Ordu, Turkey) Summary The aim of this study was to determine the effects of different rootstocks on yield characteristics and resist- ance capability against to Fusarium wilt, Verticillium wilt and Meloidogyne incognita in pepper cultivation. ‘California Wonder’ and ‘Kandil’ bell pepper varieties were grafted on ‘Snooker F 1 ’, ‘Dro F 1 ’, NGS and NGC rootstocks in the experiment. Nongrafted and self- grafted plants were used as control. Grafted plants were cultivated in open field conditions with sterilized growth media. The experiment was conducted in ran- domized split plots design with three replications. Yield was increased significantly by rootstocks in in- fected plots and it was higher than control plants in uninfected plots. The highest yield was obtained from ‘Kandil’ × ‘Dro F 1 ’ combination in Fusarium oxysporium experiment, ‘Kandil’ × ‘NGS’ combination in Verti- cillium dahlia experiment and ‘California Wonder’ × ‘Snooker F 1 ’ combination in Meloidogyne incognita ex- periment. Study showed that using of grafted plants was more effective than nongrafted and selfgrafted plants for ob- taining resistance against to Fusarium oxysporium and Meloidogyne incognita by depending on rootstocks but, not against to Verticillium dahliea. Key words. Pepper – grafting – rootstock – yield – Fusarium wilt – Verticillium wilt – root knot nematode. Introduction Pepper is one of the most popular vegetables in Turkey, and annual production is 1.81 million tonnes (ANONYMOUS 2008). Soil-borne fungal diseases and root-knot nematodes are major problems that limit pepper production in Turkey and the whole world as well. Yield and quality are decreased significantly by Fusarium oxysporium, Verticillium dahliae, Phytophthora capsici and Meloidogyne spp (root-knot nem- atodes) of pepper cultivation in protected and open field. Soil sterilization, solarisation and use of chemical fun- gicides and nematocides are common and traditional methods for fighting against to these diseases and pests. Although soil solarisation is effective method in protected cultivation, it is not suitable for in open field cultivation. Until recently, fumigant biocides such as methyl bromide and nematocides has been using commonly for getting rid of the root-knot nematodes and soil borne diseases in vegetable cultivation all around the world. Yet these chemicals were prohibited in European countries includ- ing Turkey and most of the world because of their hazard- ous effects on human health, environment, ozone layer and residues in soil and water. Consequently, scientists started to develop alternative control methods, which are more effective and environment-friendly for controlling the soil-borne plant diseases and nematodes. Grafting is taken into considered one of the most impor- tant alternative methods for controlling the soil-borne diseases in pepper cultivation. Efficiency of this method depends on resistance level of rootstocks for diseases. Recently, using of grafted seedlings has been increased in some Solanaceae vegetables such as tomato, eggplant and pepper and some Cucurbitaceae vegetables like cucum- ber, pumpkin, watermelon and melon. Grafting on resist- ant rootstocks can provide positive effects against to Fusarium wilt, Verticillium wilt, Bacterial wilt, P. capsici and root-knot nematodes in these vegetables (LEE 1994; ODA 1999; TRAKA-MAVRONA et al. 2000; LEONARDI and ROMANO 2004; RIVARD and LOUWS 2008). Rootstocks can also supply great advantages in vegetable production with strong growing performance and tolerance or resistance for abiotic stress factors such as salinity, drought, high and low temperatures (AHN et al. 1999; IOANNOUS 2001; BLETSOS et al. 2003; RIVERO et al. 2003; OKA et al. 2004; HIBAR et al. 2006; LEONARDI and GIUFFRIDA 2006; KING et al. 2008). As a result, grafting may increase the yield and quality depending on the rootstocks (DAVIS et al. 2008). The aim of this study was to determine the effect of grafted plants on control of Fusarium and Verticillium wilts and root knot nematodes in bell peppers. In addi- tion, the effects of rootstocks on yield of grafted peppers grown in sterile soil conditions were also investigated.