EFFECT OF GRAFTING ON FRUIT QUALITY IN SOILLESS TOMATO GROWING
Project no. 20276 · Status: Kapanmış · 2015
Summary
This study was carried out in autumn and spring periods of 2015-2016 in order to determine the effects of different rootstocks on tomato fruit quality in different trusses. DRW7806 F1 tomato variety was grafted onto rootstocks, namely Arazi, Beaufort, Maxifort, Spirit and Unifort. Nongrafted plants were used as control. Seedlings of tomato plants grown in open system soilless cultivation, were planted in 14.08.2015 in autumn and 08.03.2016 in spring to perlite culture in pots. The vegetation was terminated on 04.01.2016 and 30.06.2016, respectively. In order to see the effects of different periods, fruit samples were taken from the 3rd and 6th truss during the ripe-red stage. Some quality analysis (color, dry matter-DM, firmness, EC, pH, titratable acidity-TA, total soluble solids-TSS, nitrate, vitamin C, lycopene, antioxidant, phenol, N, P, K, Ca, Mg, Fe, Zn, Cu, Mn) were performed 6.11.2015 and 21.12.2015 in the autumn, 13.06.2016 and 30.06.2016 in the spring seasons at the fruits harvested from the 3rd and 6th truss, respectively. Throughout the production period, yield parameters (total and marketable yield, fruit weight, fruit number, fruit diameter, blossom-end rot-BER) were determined. Reaching ideal greenhouse indoor temperatures in spring season caused increase in some yield (total yield, fruit number) and quality (colour, firmness, DM, EC, TA, TSS, nitrate, Vitamin C, total phenol, antioxidant, lycopene) parameters and contents of some nutrients (N, K, Ca, Mg, Fe, Zn and Cu). With the use of rootstock, yield values increased in both periods compared to nongrafted plants; among the tested rootstocks Maxifort, Beaufort and Unifort gave the best performance. The yield increase was due to the increase of fruit number, weight and size of the fruits on grafted plants. The BER was only observed in the spring season and the ratio of BER fruits decreased with the use of rootstock. When the EC and TA values increased, firmness, pH, TSS, vitamin C, lycopene, Fe, Mn, Zn and Cu decreased with the use of rootstock in both periods. DM, nitrate, phenol and antioxidant contents did not change with the use of rootstock in autumn while DM, phenol and antioxidant contents decreased, nitrate increased in spring. Truss differences was found to be significant except fruit P content in the autumn, lycopene, N and Mg content in spring. While a*, C°, DM, pH, TSS, total phenol, antioxidant activity, lycopene, fruit N, Fe, Mn, Zn and Cu contents were high in the 3rd truss in autumn, these parameters -except Fe and Cu- were found higher in the 6th truss in spring. When all the results are evaluated together it was determined that the quality of fruits in different trusses can be different and temperature during fruit set is particularly effective on this change. Rootstocks have a positive effect on fruit yield and quality, hovewer rootstock genotype is an important factor on increasing yield and quality. It was concluded that the use of Maxifort and also Beaufort and Unifort rootstocks, could be more appropriate in terms of increasing fruit yield and quality in un-heated greenhouses conditions during autumn and spring periods of hydroponic tomato cultivation.