From 2003 to 2006, the blossom level and crop load of ‘Honeycrisp’ apple (Malus × domestica Borkh.) trees on M.26 rootstocks were adjusted to improve fruit quality and return bloom. The treatments consisted of manually removing flower clusters to 50, 100, and 150 per tree, then at ≈50 d after full bloom, the crop load was adjusted to 3, 6, and 9 fruit/cm2 trunk cross-sectional area (TCSA), respectively. All flower and crop load adjustment significantly increased TCSA and canopy volume compared with the control. Classic biennial bearing was observed on the untreated control trees and those thinned to 150 blossom clusters per tree and 9 fruit/cm2 TCSA and was mitigated for trees with 50 and 100 blossom clusters followed by crop load adjustment to 3 and 6 fruit/cm2 TCSA, respectively. Fruit color the “on” year was always lower on the control trees; no difference was found in the “off” year. The treatments increased fruit weight proportional to crop load except for the 2004 “off” year. This study illustrates that for trees with ≈1 m3 canopy volume, the combined effects of blossom and crop load adjustment to 100 blossom clusters/tree followed by fruitlet adjustment to 6 fruit/cm2 TCSA and below will induce consistent annual production for ‘Honeycrisp’.

Rupasinghe, H. P. V., Huber, G. M., Embree, C. and Forsline, P. L. 2010. Red-fleshed apple as a source for functional beverages. Can. J. Plant Sci. 90: 95Á100. The potential of anthocyanin pigments in fruits and vegetables to provide protection against oxidative damage is well known. Cyanidin-3-O-galactoside is a naturally occurring red pigment commonly found in skin of apples but also present in flesh of certain crab apple and apple genotypes. The purpose of this study was to investigate the cyanidin-3-O-galactoside concentration and antioxidant capacity of juice made from 14 genotypes of red-fleshed apples in comparison to three white-fleshed apple cultivars and three commercial apple juices. Cyanidin-3-O-galactoside was found only in the juice made from red-fleshed apple genotypes with the highest concentrations (39 mg L(1 ) in a crab apple Roberts Crab. The antioxidant capacity measured using the Folin-Ciocalteu, the ferric reducing antioxidant power (FRAP), and the oxygen radical absorbance capacity (ORAC) assays were the greatest in juice prepared from the red-fleshed genotypes Babine and Malus pumila Niedzwetzkyana, a red-fleshed crab apple genotype. The antioxidant capacity measures were strongly correlated with each other; however, there was no correlation between the concentration of cyanidin-3-O-galactoside and the antioxidant capacity measures. The juice quality parameters 8Brix and titratable acidity values were not significantly different among the juices made from the redfleshed apples, commercial apples and commercial apple juice products.

. 2008. Performance of prohexadione-calcium on shoot growth and fruit quality of apple * Effect of spray surfactants. Can. J. Plant Sci. 88: 165Á174. Vegetative growth control of apples (Malus )domestica Borkh.) is necessary to maintain a balance between growth and cropping. Pruning is a labour-intensive management practice to achieve this and intrinsically stimulates new growth. Prohexadione-calcium (PC) is a plant bioregulator that effectively regulates the shoot extension growth of apples and other tree fruits. Previous research has demonstrated that its efficacy can vary based on the use of spray surfactants and adjuvants. This study investigated the efficacy of two rates of Apogee TM , the commercial form of PC, used in combination with the spray surfactants Sylgard 309 and LI 700, on extension shoot growth and yield parameters.Experiments For personal use only.

No abstract

No abstract