1: Improve understanding of deciduous tree fruit stress responses and develop cultural strategies and technologies to ameliorate abiotic stress with different tree architectures and rootstock-scion combinations. 1.A. Develop and test novel genetic sources and tree architectures for increased water use efficiency. 1.B. Characterize key biochemical and physiological processes regulating fruit tree architecture and genetic-environmental interactions. 1.C. Develop cultural management practices that include rootstock and shoot architectures that are stress tolerant and improve production efficiency in high density plantings. 1.D. Develop rudimentary apple orchard carbon budget. 2: Develop new devices/technology for dectection and control of invasive and native insects in fruit crops including, but not limited to, brown marmorated stink bug, spotted wing drosophila, and the native plum curculio. 2.A. Identify and utilize attractive behavioral cues, including olfactory and visual stimuli, to develop sensitive monitoring tools and behaviorally-based control strategies within the production system that reduce insecticide inputs to increase profitability and sustainability. 2.B. Develop monitoring and management tools for the invasive brown marmorated stink bug, spotted wing drosophila, and the native plum curculio using the knowledge developed in Sub-objective 2.A. 3: Develop and apply computer vision for mechanization of orchard practices including, but not limited to, pruning. 3.A. Refine computer vision system for three-dimensional shape modeling of trees, including different tree growth habits. 3.B. Integrate computer vision system and robotics for pruning.
This project proposes the development and integration of entomological, horticultural, and engineering technology to solve major problems affecting temperate tree fruit production, the sustainability and environmental impact of tree fruit production, and consumer acceptance of tree fruits. Novel arthropod management techniques will be developed through identification of olfactory or visual cues in order to implement insect behavioral manipulation strategies that will improve monitoring and control of key insect pests. Improved light and water management will be developed through training systems that include different tree growth habits that are amenable to orchard automation and through improved understanding of hormones, rootstocks, and growth habit to optimize carbon partitioning, tree development, and water use efficiency. Future mechanization of orchard operations will be facilitated by newly developed tree management systems to improve light penetration in novel tree growth habits and by algorithms for the visualization of tree branches. The technologies and knowledge developed within this project are components of management systems that integrate behaviorally-based monitoring and management of arthropods, optimal tree architecture, and orchard automation that result in the production of high quality fruit with stable annual yields. The broad base of expertise in the research program will develop and integrate the most appropriate technologies to solve the key problems of tree fruit production. Productive and sustainable tree fruit production systems will benefit both consumers and global competitiveness of U.S. growers.
Water use efficiency is a complex genetic trait and an important plant characteristic. We studied how within-year cultural variation vs. yearly environmental variation affect ‘Loring’ peach leaf ash and carbon discrimination as measures of water use efficiency using different cultural practices for a 13-year period of time. Water use efficiency measured by the two methods was significantly related to the growing season rainfall amount and the evaporative demand, not the yearly cultural practices. These data indicate that breeding programs screening for increased water use efficiency using leaf ash or delta 13C can anticipate a minimal amount of within-location variation and thus, place more emphasis on environmental or between-location variation. Experiments were continued in the greenhouse and field to determine comparative drought hardiness of 'Gala' and 'Fuji' apples grafted to dwarfing and vigorous rootstocks (M.9 and MM.111, respectively). Under drought conditions, trees grafted to the dwarfing rootstock, M.9, had higher leaf concentrations of abscisic acid that reduced leaf water losses and likely contributed to greater water use efficiency. To study the biological foundation for tree architecture and drought tolerance, five growth habits of apple ('Royal Gala', 'Pink Lady', 'Golden Delicious', 'Fuji', and 'Honey Crisp') were propagated on four traditional Malling rootstocks (M.27, M.9, M.7, and MM.111) and four newer Geneva rootstocks (G5087, G5257, G4213, G202, and G4814). Trees were planted in the field at different planting densities and management strategies. A subset of trees is in the greenhouse for associated controlled environment experiments. Five growth habits of peach (Pillar-Compact, Narrow-leaved Pillar, Compact Redhaven, Crimson Rocket, Sweet-N-Up, and Bailey) that were propagated from seed in 2014 were grown in the greenhouse in 2015 and treated with growth regulators (including IAA, TIBA, and strigolactone) that affect bud development and tree architecture. Effects of these growth regulators, in combination with novel pruning and training techniques, remain to be conducted on Crimson Rocket, Sweet-N-Up, and Bailey in the field. We have identified visual cues that are very attractive to spotted wing drosophila (SWD) under laboratory, semi-field, and field conditions. We are quantifying how incorporation of olfactory cues, i.e., attractive host fruit odors, affects SWD response to visual cues. Ultimately, these data will be used to optimize attract-and-kill technology for SWD We are establishing distances that the brown marmorated stink bug (BMSB) will respond to pheromone+synergist lures to better establish spacing for monitoring traps and for attract-and-kill sites. We are also quantifying the size of the area of aggregation around pheromone+synergist lures to enable more precise management application zones for attract-and-kill sites. A mobile robot platform was constructed and tested in the field for the purposes of detecting tree shape from digital cameras. This computer vision system was tested in the field during the trees' dormancy, January-March 2015. A mobile background trailer was also constructed to reduce the confusion of the subject tree with other nearby trees. The existing system to reconstruct the tree shape was refined using the results of experiments in the outdoor environment. A new robot-world, hand-eye calibration procedure was established. Robot-world, hand-eye calibration is a process that determines the relationships between the robot, camera, and world coordinate frames. High-accuracy calibrations result in fewer positional errors when using robots for automation tasks. We had previously completed implementation of state-of-the-art calibration procedures, but in the reporting period, created new methods of robot-world, hand-eye calibration that are more suited to work in vision and in particular, to work with thin structures such as trees.
1. Calcined kaolin particles mitigate ozone damage in apple. Ozone levels are positively related to air temperature and the expected increase in growing season temperatures associated with climate change will result in greater ozone levels in the future. ARS scientists at Kearneysville, West Virginia, studied calcined kaolin applied to apple trees over a 6-year period. The fruit yield and quality were evaluated in addition to ambient ozone levels. The calcined kaolin particles alone catalyzed the degradation of ozone and also stimulated non-pathogenic microbial populations on the leaf surface which further increased ozone degradation and increased apple quality. The use of calcined kaolin may be one tool to mitigate increased ozone stress.
2. Pesticide rates established for control of brown marmorated stink bug (BMSB). The BMSB is a new, major pest threatening horticultural crops. ARS researchers at Kearneysville, West Virginia, developed effective short-term mitigation strategies, i.e., insecticide applications, for management of BMSB in tree fruit. Information generated from this ARS effort is now published in management guides for management of specialty crops including: Virginia, West Virginia, Maryland 2015 Spray Bulletin for Commercial Tree Fruit Growers, 2015 New Jersey Tree Fruit Production Guide, and the 2015 Pennsylvania Tree Fruit Production Guide. Adoption of recommendations for BMSB is estimated to have been used on ~50,000 acres of tree fruit in the mid-Atlantic region.
Glenn, D.M., Bassett, C.L., Dowd, S.E. 2014. Effect of pest management system on 'Empire' apple leaf phyllosphere populations. Scientia Horticulturae. 183:58-65.
Glenn, D.M., Bassett, C.L., Tworkoski, T., Scorza, R., Miller, S. 2015. Tree architecture of pillar and standard peach affect canopy transpiration and water use efficiency. Scientia Horticulturae. 187:30-34.
Kim, J.Y., Glenn, D.M. 2015. Measurement of photosynthetic response to plant water stress using a multi-modal sensing system. Transactions of the ASABE. 58(2):233-240.
Nunes De Lima, R., Figueiredo, F., Martins, A., De Deus, B., Ferraz, T., Gomes, M., De Sousa, E., Glenn, D.M., Campostrini, E. 2014. Partial rootzone drying (PRD) and regulated deficit irrigation (RDI) effects on stomal conductance, growth, photosynthetic capacity, and water-use efficiency of papaya. Scientia Horticulturae. DOI: 10.1016/j.scienta.2014.12.005.