Comparative Study on the Behavior of Some Old Apple Varieties before and after Their Grafting, with Potential for Use in Urban Horticulture

Urban horticulture has to respond to several challenges, including reducing the growth vigor of the scion/rootstock combination, adapting the cultivated species/variety to the pedoclimatic conditions-more varied in recent years, and increasing tolerance to diseases and pests that cause extensive qualitative and quantitative damage to fruit production. For this experiment, 15 old apple varieties were chosen, all known and cultivated in the Banat area, which were grafted on the MM106 rootstock. Several parameters were analyzed that can be used for a relevant classification for planting them in limited spaces, such as in a private garden. Our research started 10 years ago and has already resulted in a doctoral thesis that extensively presents the data taken from the initial biological material and the first two years after grafting the trees; the research continued and is still ongoing in the experimental orchard. From the multitude of aspects studied, we have chosen to present some results related to the vigor of the scion/rootstock combination, the quality of the fruits, their content in acidity as well as the behavior with respect to diseases and pests-results that can be useful to those who want to grow old apple varieties in their own garden. Growth vigor was reduced in most varieties, but the highest influence of the rootstock on growth was observed in the 'Banatenesc' variety, followed by 'Jonathan de Munte' and 'Caslere'. Grafting and agrotechniques had a positive influence on the fruit mass in all cultivars, except 'Cretesc', with an experimental average of 163.35 g, namely 60.56 g higher on average than that of the original biological material. After grafting, the SSC was between 10.05 degrees Brix in the 'Curcubatoase' variety and 18.48 degrees Brix in 'Parmen Auriu', with an experimental average of 14.96 degrees Brix. The fruit acidity oscillated between 0.13 g/100 g in 'Floranesti' and 'Patul' varieties and 0.46 g/100 g in 'Domnesc', with an experimental average of 0.25 g/100 g.

Automated summary

Urban horticulture faces challenges in reducing growth vigor, adapting to changing pedoclimatic conditions, and increasing tolerance to diseases and pests for better fruit production. This experiment analyzes the characteristics of 15 old apple varieties grafted on the MM106 rootstock to classify them for planting in limited spaces. The research focuses on the vigor of the scion/rootstock combination, fruit quality, acidity, and resistance to diseases and pests. Results show reduced growth vigor in most varieties, positive effects of grafting and agrotechniques on fruit mass, and variations in sugar content and acidity among the different varieties.