Effect of training system on qualitative and quantitative characteristics and concentration of nutrition elements of apple (Malus domestica) fruit

Background and objectives: Apple is the most important horticultural crops that is allocated large share of world trade in agricultural products. Principles of sustainable fruit production systems are based on optimal use of natural resources (light, water, soil fertility) where the input (labour, energy, fuel, other material) and output (yield) are well balanced and the resources remain renewable. In such a system the minimizing of environmental polluting input (fuel and agrochemicals) is essential (4). Fruit orchards can be considered as artificial ecosystems converting the energy of photosynthetic active radiation (PAR) into edible, marketable fruits for human consumption (7).The core of this system is the bio-factory of leaves driven by the absorbed PAR. Several data support that the light interception is the basic factor for the modern orchard systems, albeit further factors as LAI, the spacing the trees, training and pruning systems, the species specific fruiting wood development, rootstocks also influence the orchard efficiency (7). Therefore, in this study, the effect of three different systems (V shape, HighTech and Cordon) was investigated on qualitative and quantitative traits as well as fruit skin color and concentration of nutrition element of fruit two cultivar ‘Gala’ and ‘Delbarestival’
Material and method: In order to evaluate the types of training systems on qualitative and quantitative traits as well as fruit skin color and concentration of nutrition element an experiment was carried out with two factors including cultivar and training systems in 2013. Training systems including (V shape, HighTech and Cordon) and cultivars were ‘Gala’ and ‘Delbarestival’.
Result and discussion: The results showed that types of training systems can affect on apple fruits quality and quantity and concentration of nutrition element. Fresh and dry weight of leaves (1.47 and 0.51 gr) and leaf area (4767.2 mm2) in training systems of HighTech was higher than two other systems. The highest rate of fruit set was observed in training systems of HighTech (14.67%) and V shape (13.07%) whereas the highest rate yield and yield efficiency was observed in training system of Cordon (13.42 kg/ha and 0.88 kg/cm2) and High tech (11.23 kg/ha and 0.69 kg/cm2) , in respectively. Fruit tissue firmness and fruit skin a* value and concentration of phosphor, potassium, calcium in fruits of cultivar ‘Gala’ in each three training system were significantly higher than cultivar ‘Delbarestival’. The result indicated that rate of fruit set (13.6%5), rate of yield (14.49 kg/tree) and yield efficiency and (0.93 kg/cm2), weight fruit (123.06 gr) and rate of EC (1.21) in cultivar ‘Gala’ were significantly higher than rate of fruit set (10.86%), rate of yield and yield efficiency (7.13 kg/tree and 0.53 kg/cm2), weight fruit (101.63 gr) and rate of EC (1.01) in cultivar of ‘Delbarestival’.
Conclusion: Generally, results of investigations qualitative and quantitative traits as well as skin color of fruit and concentration of nutrition element showed that cultivar ‘Gala’ in training systems HighTech and V shape and cultivar ‘Delbarestival’ in training systems High-tech and Cordon produced fruits with more quality favorite than other system, in respectively.