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  • Author or Editor: Peter H. Jerie x
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Abstract

Peach [Prunus perscia (L.) Batsch] flowers opened first at the base of young trees and last at the top. In contrast, fruit ripened first at the top of trees and at the tips of laterals. Dry weight and percentage dry weight (% dwt) of the mesocarp of fruit from the upper canopy were consistently greater throughout the season than for fruit from the lower canopy. These differences were large enough to have marketing significance and important implications for the future of mechanical harvesting.

Open Access

Abstract

The Tatura Trellis was developed from principles to overcome problems identified in existing cultural systems (2, 3, 6). For optimum early bearing and yield, we wanted a) a tree design that fills the allotted space quickly, resulting in optimum land use; b) a uniform and controlled distribution of leaves and fruit to improve light interception (16) and photosynthetic efficiency (5); c) an ordered branch and leaf array that diminishes light competition within and between trees, so as to minimize the effects of crowding that usually result from high plant densities, especially with peach trees; d) close planting to create root competition, thereby reducing vegetative vigor while increasing fruitfulness (4); and e) large tree numbers per hectare for high yields early in the life of the planting. In addition, we proposed that within the above constraints, the new system should be simple to mechanize. The requirements we considered important were f) an orchard with planar, though not necessarily horizontal or vertical, surfaces for easy positioning of machines and aids; g) a canopy under which machines can operate to recover fruit simply during harvesting, and over the canopy for summer pruning; h) a shallow canopy to decrease the chance of fruit striking limbs or other obstructions, which could damage the fruit after they were removed mechanically (30); i) a shallow canopy to increase penetration and coverage of protective sprays; and j) single limbs that repeat at regular intervals to simplify the positioning of mechanical devices.

Open Access

Abstract

Fruit yield was increased, summer pruning decreased, and water saved when regulated deficit irrigation (RDI) and withholding irrigation (WI) were used over 5 years to manage mature ‘Bartlett’ pear ( Pyrus communis L.) trees planted at three levels of within-row spacing (0.5, 0.75, and 1.0 m) and trained to a Tatura trellis. Three levels of irrigation, 23%, 46%, and 92% replacement of evaporation from the planting square (Eps), were compared during the RDI period. Weight of summer prunings was positively and linearly related to level of irrigation in each year, including a relatively wet year. When compared between years, the degree of this response on the dried treatment was positively and significantly related to net evaporation (evaporation – rainfall) recorded during the period of rapid shoot growth. Fruit number also tended to be greater on the 23% and 46% Eps treatments in all years. Cumulative yield over 10 years of cropping did not differ between tree spacing, although fruit size was larger at the 1-m spacing. High yields were obtained at all levels of tree spacing. Yield and tree growth responded most to RDI for the 0.5-m-spaced trees.

Open Access