Rootstock, Canopy Architecture, Bark Girdling, and Scoring Influence on Growth, Productivity, and Fruit Quality at Harvest in ‘Aztec Fuji’ Apple

Abstract

The increasing scarcity of land and water for agriculture mandates an efficient use of these natural resources. Establishment of high-density orchards with the use of a size-controlling rootstock, in combination with a suitable canopy architecture, is an efficient method for fruit production. However, less attention has been paid to the use of size-controlling practices such as trunk girdling in these modern orchard systems. The impacts of two rootstocks, two tree architectures, and three levels of bark cambium cuts (girdling or scoring) on growth, yield, fruit quality attributes at harvest, and leaf nitrogen (N) in 'Aztec Fuji' apple (Malus domestica Borkh.) were studied in 2015 and 2016. Trees on Nic 29 had larger canopies, higher yields, and larger fruit, but lower fruit color, sunburn, and firmness than those on Bud 9. Trees with a tall spindle (TS) architecture had higher yield in 2016, higher fruit soluble solids and firmness in 2015, higher fruit russet in 2016, but shorter terminal growth in both 2015 and 2016 and lower leaf N in 2015 than did those with a central leader (CL) training system. Trees receiving a bark girdling in 2015 (BG15) or score girdling in 2015 and 2016 (SG1516) had significantly higher yield than trees on nongirdled trees (NOGD) in 2016. Bark girdling or score girdling in 2015 (BG15 or SG15) increased fruit weight (size), color, and firmness at harvest in the same year, although differences for score girdling were not always significant. However, BG15 or SG15 did not have a ''carryover'' effect and did not affect fruit size, color, or firmness at harvest in 2016. When bark scoring was repeated in 2016 (SG1516), fruit size was increased in 2016. On the basis of the results of this 2-year study, it appears that bark girdling in one year is sufficient to increase fruit size of the current year and the yield in the following year. If larger fruit size is the critical objective of fruit production, annual score girdling needs to be practiced. However, a further long-term study is needed to monitor the carryover effects of cambium girdling and scoring on tree performance and fruit quality attributes in the subsequent years.

Long-term Performance of ‘Delicious’ Apple Trees Grafted on Geneva® Rootstocks and Trained to Four High-density Systems under New York State Climatic Conditions

“…In contrast, 'M.9T337' together with the rest of the rootstocks, except for 'B.118' and 'M.7EMLA', had the highest CYE (Table 4), in agreement with those results reported by other authors (Autio et al, 2017;Ch avez-Gonz alez et al, 2011;Czynczyk and Bielicki, 2012;Fuller et al, 2011). Dwarfing rootstocks have been shown to have a dramatic effect on CYE (tree productivity/tree size), which determines the optimal spacing to capture light energy and convert it to fruit (Autio et al, 2013;Fallahi et al, 2018). CCL was affected by rootstock.…”

A comparison of fruit and leaf parameters of apple in three orchard training systems

“…The use of a suitable training system with appropriate pruning and bending was proved to be an efficient fruit growing practice in order to reach optimum yield and improve fruit quality (Fallahi et al, 2018). Pruning is a key component to maintain training system during the orchard lifetime and ensures a balance between tree growth and fruit yield, which is based on the fundamental knowledge that fruit yield negatively correlates with tree growth (Gandev, Dzhuvinov, 2014).…”

Girdling Effects on Fruit Maturity, Kernel Quality, and Nutritional Value of Walnuts (Juglans regia L.) alongside the Effects on Leaf Physiological Characteristics

“…The question arising from girdling concerns the long-term effects on fruit and tree. In apples, Fallahi et al [55] observed that girdling of the bark was effective for two years production, while in kiwi fruit, extended and successive girdling for four years was beneficial without a decline in productivity or quality thereafter [56]. Therefore, experiments should be carried out investigating the effects on fruit and trees without/with repeated girdling each year, including various factors that could influence the effect, such as the cultivar [57], time of application, and others.…”