TREE PERFORMANCE, FRUIT QUALITY, AND MINERAL NUTRITION OF `DELICIOUS' APPLE STRAINS.

Abstract

Tree performance and fruit quality at harvest and after storage and leaf mineral nutrition in 28 strains of `Delicious' apple were studied over several years. `Classic Red', `Hi-Early`, `Nured Royal', `Rose Red', and `Sharp Red' had bigger trunk cross sectional area (TCSA), while `Starking`, 'August Red`, and `Apex' had both bigger TCSA and cumulative yields. `Red King Oregon Spur' and `Improved Ryan Spur' had a high yield efficiency. `Aomori' `Atwood', `Redchief`, and `Hardispur' had low cumulative yields and yield efficiencies. `Rose Red', `Red King Oregon Spur', `Ace', `Imperial', `Starking', and `Wellspur' had heavier fruit, while `August Red', `Hardispur' and `Starkrimson' had smaller fruit than most other strains. `Starkspur Supreme' had the highest L/D ratio and `Early Red One' and `Rose Red` had higher red color than those of all other strains. `Aomori', `Hardispur`, `Nured Royal', `Silverspur` and `Starkrimson' had high soluble solids concentrations. Differences were observed in the leaf mineral concentrations between different strains. `Apex', `Classic Red' and `Silverspur' had a high overall acceptability, while `Sturdeespur', `Hardispur' and `Aomori' were not acceptable.