A set of 3 experiments was conducted to determine if cellulose fibers (CF) could reduce the incidence of sunburn injury in `Paulared' apples. Sunburn injury was artificially increased in these experiments by fruit manipulation and removal of shading vegetative growth to expose apples to at least 4 hours of direct sunlight. The 4 treatments applied included an unsprayed control, a commercial binding agent (CBA), a 1% corn starch (CS) colloidal suspension, and a 3% CF suspension that contains CBA and CS. No differences between treatments were found in the first experiment. The CF suspension concentration was increased to 9% for the second experiment. This resulted in uneven CF distribution on the fruit surface and no significant differences between treatments. The third experiment was designed to more precisely determine sunburn symptom expression by delineating the manipulated fruit surface area directly exposed to sunlight prior to treatment. The resulting percent of area that showed a white (bleached) sunburn symptom was significantly less for the apple fruit treated with CF than CBA alone.
Alvan Gaus and Matthew Rogoyski
Alvan Gaus and Matthew Rogoyski
The main objective of this research was to compare the growth responses of l-year-old, vertical, apple shoots to bending with a simple hand-tool (HT) or bending with the commercially available Branch Bender® (BB). Single, vigorous, vertical shoots of `Red Chief Delicious (RCD), `Valnur' Jonathan (VJ), and Granny Smith were either bent with the BB or were bent by spirally wrapping the shoot around a 2.5 cm diameter plastic-rod, HT 2 times. Each variety had nine single-tree blocks with a control, BB, and HT as treatments. Measurements were taken on the number of clusters formed, length of subsequent terminal growth, number of shoots and spurs formed, and shoot cross-sectional area. No differences were found in RCD between the BB and the HT on all parameters; however, terminal growth was less with the BB than the control. With VJ, first year shoot cross-sectional area for the BB was less than for the HT. Cluster formation on both 1 and 2-year-old wood was greater with the BB than the control but not with the HT. No differences were found with Granny Smith.
Matthew K. Rogoyski and A. Richard Renquist
A decision support system has been developed to help Colorado fruit growers with apple (Malus domestica Borkh.) thinning. This system can also be used as a teaching aid and as a tool for generating research hypotheses. The system determines if fruit thinning is needed by identifying catastrophic events that would eliminate the need for thinning. The major function of this decision support system is determination of tree responsiveness to chemical thinning agents. This is accomplished through analysis of the user's answers to questions related to the physiological status of the trees, environmental data, bearing history, and the apple variety in question. On the basis of the above analysis, two sets of recommendations are presented: general recommendations based on the variety selected, and specific ones for that variety based on growth stage and tree responsiveness to thinners. The user also is provided with the rationale for the recommendations.
Matthew Rogoyski, Alvan Gaus, Byron McNew, Israel Broner, and Thomas Mourney
A simulator of a control system for evaporative cooling of crop canopies was developed. This development, prior to implementation of an irrigation/cooling system, allowed for experimentation before committing resources to the field system. The project provided insight into problems of modeling interaction between biological, mechanical, and digital systems and demonstrated how specialists from diverse areas can solve these problems. The object orientation methodology and the C++ programming language were tools for development of this simulator. A communication mechanism was devised to facilitate interactions between software entities representing both concrete and abstract objects corresponding to the problem domain. The object-oriented approach to the system development allowed for better communication between team members, irrespective of their background in software engineering. The modular and polymorphic nature of the object-oriented code made it possible to plan for code reuse in future projects. Simulator development using the object-oriented paradigm was found to be preferable over the procedural model used by team members in other projects in the past.
Matthew Rogoyski, Alvan Gaus, Thomas Mourey, Israel Broner, and Jeffrey Lakey
A novel way to capture long-standing agricultural experience and knowledge in the form of generative patterns is proposed. These patterns can be thought of as solution paradigm where the solutions are the essence of the patterns. A pattern does not provide a concrete solution to a problem but can be considered of as a worldview of the problem or a solution space. A pattern initiates and generates human cognitive behaviors that indirectly facilitate, elucidate, and solve a problem. An application of generative patterns to production agriculture is proposed. An individual pattern, as described here, associates a problem, its context, the forces affecting it, and a solution. A pattern recurring in production agriculture, the socalled uniformity pattern, is presented, and its horticultural example is discussed.
Matthew Rogoyski, Alvan Gaus, Israel Broner, and Thomas Mourey
An evaporative cooling system for apple trees was implemented. The system is automated to conserve irrigation water. The automation is based on the digital, integrated thermometer and thermostat chip embedded in the artificial fruit. The thermometer–thermostat chip drives a solid state relay. The relay controls a solenoid operated valve. A typical duty cycle consisted of 1 to 2 minutes of wetting (water on) to 4 to 10 minutes drying (water off). Differences in the length of duty cycles between individual chips were observed. The reliability of the system was adequate. The waterproofing of the system's electrical components was its weak point. Irrigation water deposits accumulated on the apple fruit surface during the growing season were readily removable with a simulated brush technique.