EVALUATION OF QUALITY TRAITS AND YIELD OF 28 STRAINS OF DELICIOUS APPLE

Traits contributing to yield and fruit quality of 28 spur and standard growth habit strains of 'Delicious' apple (Malus domestica Borkh.) we re studied. Cumulative per tree yield to seventh leaf (precocity) was consistently greater in the spur strains averaging 33.7 kg compared to 20.4 kg for standard strains. Mature tree yield was nearly equal for the two tree types but average This efficiency war higher for the spur strains. was reflected in higher calculated per hectare yields (45.1 compared to 28.8 tonnes), Color and size grades were determined on a c ommercial graping line. The standard strain 'Early Red One' was notabl e as the best coloring strain and also had a higher efficiency ratio t han other standard strains in the fifth crop. Color of strains ranged from a high of 59% to 0% (B.C. extra fancy) with most spur strains dev eloping less color than standard ones; but the spur strains 'Ace', 'Re d King Oregon Spur' and 'Improved Ryan Spur' were highly ranked for co lor. The spur strains with poorer color also had smaller fruit. 'Red K ing Oregon Spur' and 'Aomori' had larger fruit than other strains. Fru it shape, seed number, soluble solids and flesh firmness of strains va ried less than color and yield determining traits.