TOMATO FRUIT YIELD AND QUALITY AS AFFECTED BY GRAFTING AND GROWING SYSTEM

Abstract

An experiment was conducted to study the effect of grafting on yield, quality and shelf life of tomato using simplified open soilless system vs. conventional soil cultivation. The experiment was carried out at Al-Karama station which represents areas north of the Dead Sea where soil salinity is the limiting factor for higher yields. Cecilia F1 cv. (most commercial tomato cultivar grown in Jordan) grafted on two rootstocks (He-man and Spirit) was compared with non-grafted Cecilia (control) plants in both simplified open soilless system (containers filled with volcanic tuff) and conventional soil cultivation. Uniform 45 days-old seedlings of grafted and nongrafted Cecilia were transplanted in two 500m 2 uncontrolled plastic houses on Nov. 4, 2004, irrigated with nutrient solution after taking into consideration nutrients available in irrigation water. Fruits were harvested at full mature stage to determine fruit yield, number of fruits per plant and fruit weight. Random fruit samples from cluster 3 and 5 were used to determine fruit outer and inner quality and shelf life. The results showed that fruit yield was improved by grafting in both growing systems. Fruit yield increased by 12-27% in soilless cultivation and by 16-38% in soil cultivation with grafting Cecilia on He-Man and Spirit, respectively. Fruit quality in terms of total soluble solids, antioxidant capacities, vitamin C, lycopene and βcarotene content were reduced or slightly improved by grafting in both growing systems. However, fruit size and shelf life were not affected and fruit firmness improved by grafting but these parameters were improved in soilless as compared with soil cultivation. This variations in our results between soilless and soil cultivation and the behavior of the rootstocks might due to the fact that plants grown in soilless culture were not under salt stress as compared with those grown in soil. The result also showed that using simplified open soilless system improved productivity and fruit quality in terms of fruit size, shelf life and firmness. However, more studies needed o determine the effect of grafting on inner quality of tomato fruit.