Controlled environment agriculture, including greenhouses and indoor production facilities, is becoming an increasingly important part of the global food system. Totally enclosed, indoor vegetable growing facilities were developed in Japan beginning
Marc W. van Iersel, Geoffrey Weaver, Michael T. Martin, Rhuanito S. Ferrarezi, Erico Mattos, and Mark Haidekker
Rhuanito Soranz Ferrarezi, Sue K. Dove, and Marc W. van Iersel
labor ( USDA, 2010 ), and technological innovations, which reduce labor dependency, can help growers stay competitive. Automation can be achieved using technologies such as robots, sensors, and computer-controlled systems, which may also improve plant
Scott Henderson, David Gholami, and Youbin Zheng
to use. Apparently, more research is in need to quantify microclimatic variations within greenhouses and also to test whether soil moisture sensor-based systems are suitable for monitoring and controlling irrigation of greenhouse crops with the
Thomas Graham and Michael A. Dixon
to safely retain residual ozone in the irrigation solution during distribution to the crop is significant in that it may allow for the control of pests/pathogens throughout the irrigation system and may in fact have some efficacy in the control of
D.L. Barney, C.J. Mancuso, and T.L. Finnerty
An inexpensive controlled freezing system that allows the temperature regime of eight modular sample chambers to be varied independently was constructed. A microcomputer-based data acquisition and control unit controls the freeze-thaw cycle in each of the chambers, as well as recording sample temperatures at desired time intervals. The computer also controls the freeze-thaw cycles in, and records data from, two differential thermal analysis units and records data from an electrical conductivity meter.
Amanda Bayer, Imran Mahbub, Matthew Chappell, John Ruter, and Marc W. van Iersel
. Plants were hand-watered during the first week, after which the irrigation treatments were started. Treatments and data collection. Plants were watered using a soil moisture sensor-controlled, automated irrigation system similar to that described by
Takanori Kuronuma and Hitoshi Watanabe
and has high water retention capacity, such green roof soils, which mainly consist of a perlite, are widely used for extensive green roofs in Japan. The plants were placed in a totally controlled environmental system (phytotron) and grown about 3 weeks
Rico A. González, Daniel K. Struve, and Larry C. Brown
An irrigation control system has been developed and used to estimate evapotranspiration of contamer-grown plants by monitoring randomly selected plants within a container block and watering on an “as needed” basis. Sensor reliability and operational ease allows application of the system in a wide variety of field conditions. First-year tests, using red oak (Quercus rubra L.) seedlings, showed a reduction of 95% or better in both total irrigation and leachate rates with the computer-controlled treatment relative to a manually controlled, drip irrigation treatment without reducing plant growth.
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.
Mohamed Benmoussa and Laurent Gauthier
To achieve high yield and better quality of soilless greenhouse tomato, it is necessary to keep the nutrient concentrations in the root environment at the target levels. Dynamic control of the nutrient solution composition can be used for this purpose. We developed a computer program that dynamically adjusts nutrient solution compositions based on various climatic and agronomic characteristics. The program integrates nutrient uptake and crop transpiration models and is part of a general-purpose greenhouse management and control software system developed at Laval University (GX). The architecture of the system and some simulation results comparing the effect of various control scenarios on the evolution of the composition of nutrient solutions are presented.