influence of grafting on yield of two tomato cultivars (Lycopersicon esculentum Mill.) grown in a plastic house

The influence of different grafting methods on the success of grafting and fruit yield of two tomato cultivars (Lycopersicon esculentum Mill.) was studied in a greenhouse trial in Ljubljana. The cultivars used as scion were 'Monroe' and 'Belle', and as rootstock 'PG 3' and 'Beaufort'. Two grafting methods were applied: cleft grafting and tube grafting. Grafted plants were then hand planted in a plastic house. The treatments applied in each cultivar were: cleft grafting onto 'PG 3' and 'Beaufort', and tube grafting onto 'PG3' and 'Beaufort', and ungrafted control. The following measurements were recorded: number of plants that survived until the transplanting date; fruit yield (g plant-1) and total number of fruits harvested per plant. The high percentage (79-100%) of succesful grafting observed for both tomato scions and rootstocks, using cleft and tube grafting methods, indicated that both grafting methods are suitable for tomato grafting. A positive effect of grafting was recorded when 'Monroe' was used as scion, and 'Beaufort' as rootstock. When 'Belle' was used as scion, a negative effect of grafting was observed, since the total fruit yield of non-grafted plants was significantly higher than that of plants grafted onto both rootstock cultivars. Grafting is thus considered an important technique for sustainable greenhouse production of fruit-bearing vegetables.