. Pedigree and proposed genotypes of the ‘A72’ ( Nn ) × columnar ( brbr ) peach tree cross evaluated for the interaction of growth habit and for leaf color (red = Gr , green = grgr ) in this study. Additional populations, smaller in size, were also
the pillar (columnar) growth habit, and were planted at the AFRS orchards, Kearneysville, WV. The trees were a selection designated KV93479 on ‘Lovell’ rootstock and were beginning their seventh growing season at the time of treatment. Fruit size on
The genetically available range in tree fruit architecture has not been fully utilized for tree fruit breeding or production. Higher planting densities, new training systems, high coats of pruning, the need to eliminate ladders in the orchard, and mechanized harvesting require a re-evaluation of tree architecture. Dwarf, semidwarf, columnar, and spur-type trees may be more efficient than standard tree forms, especially when combined with specific production systems. Studies of the growth of novel tree types and elucidation of the inheritance of growth habit components may allow breeders to combine canopy growth characteristics to produce trees tailored to evolving production systems.
Abstract
Branch growth of compact (CT) and “Pillar” (PI) peach [Prunus persica (L.) Batsch.], a columnar growth type, and progeny of CT × PI was analyzed. PI trees were distinguished from CT trees by narrower branch angles and relatively fewer and longer branches. CT × PI hybridization produced two distinct classes of trees in a 1:1 ratio—globe shape (GL) and upright (UP). GL trees had a large number of branches, resembling CT trees, but had narrower branch angles. UP trees resembled PI trees, but with wider branch angles. Analysis of seedling growth at 1, 2, and 3 months indicated that height and number of lateral branches could be used to classify UP and GL mature tree form. Branch angle measured at 2 months was important in distinguishing GL from CT seedlings. Such measurements on young seedlings may be used for early selection of growth habit. The reported results indicate that peach tree form, in respect to branching density and branch angle, can be readily manipulated through hybridization of the appropriate growth types. The columnar form of the PI tree suggests its potential for high-density production systems and its use as a parent in developing narrow canopied trees.
measuring changes in microclimate and tree performance inside insect-exclusionary cages. The use of trade names in this publication does not imply endorsement by Cornell Univ. of the products named, nor criticism of similar ones not mentioned. Partial
Peach trees with a pillar (P) (columnar) or upright (UP) growth habit were planted at four in-row spacings (1.5, 2.0, 4.0, and 6.0 m) in 1999 and trained to a central leader or multiple leader system to evaluate their performance in an orchard environment. A standard (S) form peach cultivar (`Harrow Beauty') was included for comparison. In this replicated study using a split-split-split plot design, one-half of the trees were summer pruned (SP) 6 weeks before harvest in each growing season from 2001 to 2003. Growth habit, tree spacing, and SP had a significant effect on tree growth and time necessary for dormant pruning. Growth habit and spacing also affected time required to summer prune. Total pruning time for all growth habits was significantly greater for SP trees compared to non-SP trees. Cumulative yields per tree were greater for UP and S habit trees than P trees over the first four seasons. Per tree yields increased as the in-row spacing increased but were decreased slightly by SP. UP trees consistently produced larger size fruit than P or S trees. Potential yields per ha and pruning times based on projected best tree spacings will be presented. UP form trees provide a good transition for growers going from low-density to high-density peach systems, with significant advantages in yield and fruit quality.
The authors extend appreciation to M. Demuth and L. Gilreath for excellent technical assistance in tree production and evaluation of growth habit and M. Pooler for assistance in data analysis.
Seedlings obtained from mutations on conifer trees exhibit populations of dwarf shrubs. The general characteristics of the shrubs often differ from progeny to progeny. The most obvious difference between progenies is in annual rates of growth, with some showing growth rates 10 or more times greater than the slowest growing group. Differences that appear within each progeny include needle length, foliage coloration, branching habit and plant form. As a consequence, many interesting forms have been produced and named that are miniature, dwarf, and intermediate in size.
Variations in form include plants that are columnar, rounded, spreading, and weeping. Whereas variation in foliage color include blue-green, green, and gold.
The response of young, nonbearing peach [Prunus persica (L.) Batsch] trees to pruning was studied in six distinct growth forms including semidwarf, spur-type, upright, columnar or pillar, weeping, and standard. Two years after field planting, pillar and upright trees were trained to slender spindle. Semidwarf, spur-type, and standard trees were trained to the open or delayed vase form. Weeping trees were pruned in a manner similar to the Lepage hedge for pear. Branch density before pruning was highest in semidwarf, spur-type, and upright trees and lowest in pillar trees. Standard, semidwarf, and spur-type trees reacted similarly to pruning, but semidwarf trees produced as much wood in the following season as had been pruned off, and produced large numbers of fruiting branches. The small size of semidwarf trees suggested their use for medium-density plantings (MDPs). Pillar trees needed only light pruning. No major cuts were necessary and many fruiting branches were produced even on nonpruned trees. The pillar canopy was 60% thinner and required 50% fewer pruning cuts than the standard canopy and may be particularly suited to high-density plantings (HDPs). The upper canopy of weeping trees grew more than most other forms. They were intermediate in branch density and required an intermediate amount of pruning. Most striking was the unique canopy form of weeping trees, which may be used in developing new training systems. The results of this study suggest that new growth forms have the potential to reduce pruning and training requirements for peach, particularly in MDPs and HDPs. This potential suggests further investigation and exploitation of alternate peach tree growth forms.
of Novi Sad, Novi Sad, Serbia. The tree has columnar growth habit that, depending on the rootstock vigor, makes it an excellent commercial cultivar for use as a late-harvested dessert apple, as well as in amateur orchards or in potted growing