Improving sustainability of North Central Region peach production through novel training systems and optimization of branch angle.

View the project final report

Commodities

• Fruits: peaches

Practices

• Crop Production: cropping systems, plant breeding and genetics, varieties and cultivars
• Education and Training: demonstration, extension

Training fruit trees to high-density, planar canopy systems can increase sustainability by decreasing labor and pesticide inputs, while increasing fruit quality, yield per acre, and worker safety. However, high-density, planar systems are difficult to implement in peach (Prunus persica) because peach has very high vegetative vigor. This excessive vigor makes training difficult and increases labor costs.

This project explored how genetically-controlled differences in branch angle could be combined with innovative training strategies to facilitate high-density systems for peach.

First, we examined how altering the number of leaders in planar training systems affected yield, fruit quality, and vigor in the cultivar “Bounty”. We found that the single leader system (Super Spindle Axe; SSA) and the system with multiple (4-8) leaders (Upright Fruiting Offshoots; UFO) improved early yield (4^th-6^th leaf), when compared to a free-standing three-dimensional system (Quad-SSA; QSSA). This increase in yield did not come with any observed cost to fruit quality, which was not significantly different for any system. The amount of excess vegetative growth removed during pruning remained largely constant per row-foot regardless of the tree density. This suggests that increasing density may be as effective as increasing leader number at controlling vegetative vigor.

Second, we examined the performance of three varieties with different branch angles in two different planar training systems—one with two leaders, and one with six or more leaders. While significant differences in yield and fruit quality were observed among the varieties, no differences in performance were observed for any variety between the two training systems. An intermediate branch angle was observed to facilitate training activities such as pruning and tying.

Third, we engaged with growers to try to understand what they view as major obstacles to adopting high-density systems in peach. While presentations at grower conferences elicited interest in the training systems we trialed, we were unable to get sufficient responses to our survey to draw general conclusions about grower concerns about high-density, planar systems.

• Trial whether high-density, planar systems could improve yield and fruit quality in peach.
• Compare planar systems with differing numbers and densities of leaders.
• Test how branch angle impacts what training system works best.
• Understand what variation in architecture is available in commercial peach varieties.
• Identify growers’ concerns about high-density, planar systems in peach.