Influence of Rootstock on Physiological Charachteristics, Growth, Cropping and Nutrient Uptake of  Golden Deliciou's Apple

Influence of different rootstocks on fruit yield and some vegetative and reproductive traits of ‘Golden Delicious’ apple during four seasons (2008-2011, 5-8 year old respectively), togheder with some physiological characteristics and content of minerals during two seasons (2010-2011) were evaluated. The results indicated significant effects of rootstock on net photosynthesis (Pn), transpiration (Tr), CO2 concentration (Ci), mineral uptake and cropping of ‘Golden Delicious’ apple trees grafted on M.9, MM.106, MM.111 and seedling rootstocks. Net photosynthesis and mesophilic conductance were higher in trees grafted on M9 rootstock than other rootstocks. Alternatively, MM106 and MM.111 had the lowest and the highest rate of transpiration respectively. Significant differences existed among rootstocks in terms of stomatal conductance, CO2 concentration and leaf temperature. However, correlation was not observed between growth vigor and those traits. Effect of rootstocks on cropping was significant and trees on seedling had the highest yield per tree but the lowest yield efficiency, while M9 rootstock had the highest. Tree height, trunk cross sectional area, leaf area, Chlorophyll contents and number of flowers were influenced by rootstock type. The potential of mineral uptake in evaluated rootstocks was different. Rootstocks had significant effect only for N, K, Ca, Mg, Fe, Mn, Zn and Cu.