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Electric lamps are widely used to supplement sunlight (supplemental lighting) and daylength extension (photoperiodic lighting) for the production of horticultural crops in greenhouses and controlled environments. Recent advances in light-emitting diode (LED) technology now provide the horticultural industry with multiple lighting options. However, growers are unable to compare technologies and LED options because of insufficient data on lamp performance metrics. Here, we propose a standardized product label that facilitates the comparison of lamps across manufacturers. This label includes the photosynthetically active radiation (PAR) efficacy, PAR conversion efficiency, photon flux density output in key wave bands, as well as the phytochrome photostationary state (PSS), red/far red ratio, and graphs of the normalized photon flux density across the 300–900 nm wave band and a horizontal distribution of the light output.

Industrial and systems engineering has been widely applied to analyze and optimize complex processes in various industries taking a highly computational approach. Plant factory-based production systems can utilize the same approach to effectively increase efficiency and reduce the cost of crop production under controlled environment. This chapter introduces our transdisciplinary work of integrating controlled environment crop production technologies, industrial and systems engineering, and agricultural economics using plant propagation nursery industries and their supply chain as a model case.

To increase the available photosynthetic photon flux (PPF) for plant growth, greenhouse growers sometimes use electric lighting to supplement solar light. The conventional lighting technology used to increase PPF in the greenhouse is high-pressure sodium lamps (HPS). A potential alternative to HPS is high-intensity light-emitting diodes (LEDs). The objective of this study is to compare supplemental LED lighting with supplemental HPS lighting in terms of plant growth and morphology as well as discuss the energy use efficiencies of the fixtures. There were three light treatments: 1) blue LED (peak wavelength 443 nm); 2) red LED (peak wavelength 633 nm); and 3) HPS, to provide 3.7 ± 0.2 mol·m−2·d−1 (background solar radiation of 6.3 ± 0.9 mol·m−2·d−1). Cucumber (Cucumis sativus) plants at the transplanting stage (26 to 37 days) under HPS had 28% greater dry mass than did plants under the LED treatments. This can be attributed to the higher leaf temperature under the HPS treatment. No differences were observed in growth parameters (dry mass, fresh weight, or number of leaves) between the blue and red LED treatments. Plants under the blue LED treatment had greater net photosynthetic rate and stomatal conductance (gS) than those under the red LED and HPS treatments. Plants under the blue LED and HPS treatments had 46% and 61% greater hypocotyl length than those under the red LED, respectively. The fixture PPF efficiencies used in the experiment were 1.9, 1.7, and 1.64 μmol·J−1 for the blue LED, red LED, and HPS treatments, respectively; however, the fixture growing efficiency (g·kWh−1) of HPS was 6% and 17% greater than the blue LED and red LED treatment, respectively. In summary, supplemental red LED produced desirable plant compactness and HPS had greater fixture growing efficiency than LEDs.

Better monitoring of workers' and the materials' flow within a production system can potentially enhance any facility's productivity and efficiency. This paper proposes a data driven framework to affordably localise indoor workers and materials using a passive radio frequency identification (RFID) system in large scale. Here, indoor wireless sensor networks are developed via passive Ultra-High Frequency (UHF) tags, where received signal strength indicator (RSSI) is measured by different access points (APs) to generate a fingerprinting database. Then, this database not only translates the signal strength reported by APs to distance through regression models but also helps to localise each tag utilising our proposed k-nearest neighbours (KNN) algorithm. Our improved KNN algorithm dynamically defines different neighbourhoods, in terms of size and topology considering environment status. Results from multiple experiments under different scenarios reveal that our proposed methods can detect and localise objects with an error as low as 0.36 m.

Grafting of fruiting vegetables is a relatively new advent in the United States with promise as a technology to improve both yields and the environment. However, investing in a commercial-sized grafting enterprise requires substantial capital investment and is a risky endeavor. A tool to help evaluate grafting costs for different production technologies and sizes of operation is a useful decision aid for individuals investing in new or modifying existing operations to produce grafted plants. Using a combination of engineering and financial equations, a scenario-based analysis was completed to obtain approximate capital and variable costs per plant for both new and existing production facilities. For exemplary purposes, four scenarios consisting of two different crops (tomato and watermelon) at two production sizes with different technology levels [low-volume manual grafting (one million plants per year) and high-volume fully automated grafting (100 million plants per year)] are presented to compare costs. For simplification purpose, consistent weekly production was assumed in the cost simulation. Total capital costs were $115,127 and $118,974 for low-volume production for grafted tomato and watermelon plants, respectively. They were $21.6 million and $16.7 million under high-volume production for tomato and watermelon, respectively. Among the four scenarios evaluated, variable costs per plant (costs of plants produced) were lowest for watermelons with high-volume production ($0.089 per plant), suggesting that production costs of grafted plants could decrease by scaling up production and introducing automation. Sensitivity analyses for high-volume production of tomato showed that the electricity rate, grafting clip price, and grafting robot speed were factors with the greatest influence on costs of plants. Scenario-based cost analysis was shown to be an effective tool for developing strategies to reduce the price of grafted plants.

For vegetable seedling propagators, integrating grafting technology into their propagation operations is critical to keeping or expanding market share in the near future. In this paper, an integrated discrete event simulation and Analytic Hierarchy Process (AHP) approach is proposed to help vegetable seedling propagators design grafting operation. The proposed approach consists of four steps: (1) defining performance criteria and factors (i.e. system alternative parameters and noise factors), (2) identifying significant factors via Design of Experiment (DOE), (3) evaluating system alternatives, and (4) AHP. For steps 2 and 3, a generic propagation simulator is developed with the focus on specific grafting operations (e.g. creating rootstocks, scions and grafted seedlings) while considering biological factors (e.g. seed disease and disease infection). Both classic and fuzzy AHP methods are adopted for addressing multiple criteria (e.g. variable cost, grafting throughput time, total capital expenses, resource utilization and percentage of order fulfilled in time with acceptable quality) of decisions. To address the imprecise ranking led by utilizing sample means of alternative performance data in pairwise comparison, a Best Alternative Search (BAS) procedure is proposed for AHP by considering bounds of confidence intervals in ranking alternatives. In the experiments, six system alternatives involving three automation levels (e.g. manual, semi- and fully-automated grafting) and eight scenarios are applied to a large-scale seedling propagator located in North America. Results demonstrate that (1) classic AHP produces the similar trend as fuzzy AHP, (2) the proposed BAS procedure can ensure the ranking accuracy of AHP, and (3) the proposed approach can be successfully used by vegetable seedling propagators to support the design of a grafting operation.

In addition to ventilation, daily cooling must be provided for greenhouses located in semiarid climates to maintain the desired climate conditions for year-round crop production. High-pressure fogging systems have been successfully developed for greenhouse cooling. However the lack of control strategies, in combination with ventilation systems, especially passive ventilation, has limited their capabilities. A new cooling control strategy, which considered the contribution of humidification and cooling from the crop, was evaluated by computer simulations. The strategy controlled the amount of fog introduced into the greenhouse, as well as the percentage of vent openings to maintain desired values of greenhouse atmospheric vapour pressure deficit (VPD) and enthalpy, respectively, which would consequently affect air temperature. The performance was compared to constant fogging rate strategy, which was based on VPD. On average, the new strategy saved 36% water and consumed 30% less electric energy. Smaller air temperature and relative humidity fluctuations, and more consistent control, were achieved by varying the fog system operating pressure to provide a more optimum amount of fog for evaporative cooling. It was demonstrated by simulations that dynamically varying the fog rate and properly selecting the number of nozzles, savings of water and electric energy were increased, while still maintaining acceptable VPD and temperature. The improvements in the greenhouse climate achieved by the new strategy were due to its ability to dynamically manipulate fog rates, as well as, the vent configurations.

The optimal amount of vegetable consumption required to reduce chronic disease risk is widely debated. Intervention trials evaluating biological activity of vegetables at various doses are limited. We conducted a 3-dose, crossover feeding trial to test the hypothesis that vegetable intake is associated in a dose-dependent manner with increased plasma carotenoids and subsequently reduced oxidative stress and inflammation in 49 overweight, postmenopausal women. Participants were assigned in random order to 2 (130 g), 5 (287 g), and 10 (614 g) daily servings of fresh, greenhouse-grown vegetables for 3-wk intervals with a 4-wk washout period between treatments. Plasma total carotenoids significantly increased from 1.63 to 2.07 μmol/L with a dose of 2 vegetable servings, from 1.49 to 2.84 μmol/L with a dose of 5 vegetable servings, and from 1.40 to 4.42 μmol/L with a dose of 10 vegetable servings (pre-post paired ttests, all P < 0.001). The change during each feeding period increased with each dose level (P < 0.001). Urine concentrations of 8-isoprostane F2α, hexanoyl lysine, and serum high sensitivity C-reactive protein were not affected by any administered vegetable dose. In this variable-dose vegetable study, a dose-response for plasma carotenoids was demonstrated without significant change in oxidative stress and inflammation in overweight, postmenopausal women.

Vegetable production with grafted seedlings was originated in Japan and Korea to avoid the serious crop loss caused by infection of soil-borne diseases aggravated by successive cropping. This practice is now rapidly spreading and expanding over the world. Vegetable grafting has been safely adapted for the production of organic as well as environmentally friendly produce and minimizes uptake of undesirable agrochemical residues. The number and size of commercial vegetable seedling producers has increased markedly reflecting the increase in farmers’ preferences for grafted seedlings of high-quality and better performance. In addition to the widely recognized advantages of disease tolerance and high crop yields, grafting technology is also highly effective in ameliorating crop losses caused by adverse environmental conditions such as low soil temperature and high soil salts, especially under protected cultivations where successive cropping or continuous farming is routinely practiced. Grafted seedlings are much favored in hydroponics farming systems where the chances of rapid spread of noxious diseases, once infected, is high. Active research has been focused to develop efficient rootstocks and handy grafting tools. In addition, researchers are eager to develop grafting machines or robots to reduce the higher price of grafted seedlings. The quality of grafted transplants is extremely important to maximize high-quality crop yield. Use of grafted vegetables has increased with the increased use of improved soil mix or substrate, farmer's preferences for better seedlings, efficient management of nursery systems, lower prices of grafted seedlings, and efficient nationwide delivery and/or transportation system. Improved grafting methods to cut down the labor cost for grafting and subsequent handling of plug-grown grafted transplants will contribute further to the increased use of grafted vegetables worldwide.

Grafting is an important integrated pest management strategy to manage soilborne pathogens and other pests of solanaceous and cucurbitaceous crops. Important diseases managed by grafting are caused by fungal pathogens such as Verticillium, Fusarium, Pyrenochaeta and Monosporascus; oomycete pathogens like Phytophthora; bacterial pathogens, particularly Ralstonia; root knot nematodes and several soil-borne virus pathogens. Rootstocks can include intraspecific selections that utilize specific major resistance genes and interspecific and intergeneric selections that exploit non-host resistance mechanisms or multigenic resistance. Rootstock selection has also been documented to impact foliar pests including pathogens, arthropods and viruses. Over-reliance on specific rootstocks in production systems has led to the emergence of new pathogens or shifts in the host specificity of the pathogen population, emphasizing the need for multi-tactic approaches to manage soilborne pathogens. One advantage and associated challenge of grafting is that rootstock selection for disease management is site specific depending on the presence, population structure and dynamics of the pathogen, as well as edaphic, environmental and anthropogenic factors. The use of grafting as an Integrated pest management tool to manage biotic stress will be most successful when carried out with increasing knowledge about the biology, diversity, and population dynamics of the pathogen or other pests and when complemented with sustainable farming system practices. This review highlights major uses of grafting to manage soilborne pathogens, provides some novel information on managing foliar or other soilborne pests (insects, mites, weeds) and offers discussion on future research and applications.

Conventional greenhouse environmental conditions are determined by observation. However, destructive or invasive contact measurements are not practical for real-time monitoring and control applications. At the canopy scale, machine vision has the potential to identify emerging stresses and guide sampling for identification of the stressor. A machine vision-guided plant sensing and monitoring system was used to detect calcium deficiency in lettuce crops grown in greenhouse conditions using temporal, color and morphological changes of the plant. The machine vision system consisted of two main components: a robotic camera positioning system and an image processing module. The machine vision system extracted plant features to determine overall plant growth and health status, including top projected canopy area (TPCA) as a morphological feature; red-green-blue (RGB) and hue-saturation-luminance (HSL) values as color features; and entropy, energy, contrast, and homogeneity as textural features. The machine vision-guided system was capable of extracting plant morphological, textural and temporal features autonomously. The methodology developed was capable of identifying calcium-deficient lettuce plants 1 day prior to visual stress detection by human vision. Of the extracted plant features, TPCA, energy, entropy, and homogeneity were the most promising markers for timely detection of calcium deficiency in the lettuce crop studied.

Greenhouse crop production systems are located throughout the world within a wide range of climatic conditions. To achieve environmental conditions favorable for plant growth, greenhouses are designed with various components, structural shapes, and numerous types of glazing materials. They are operated differently according to each condition. To improve the pedagogy and the understanding of the complexity and dynamic behavior of greenhouse environments with different configurations, an interactive, dynamic greenhouse environment simulator was developed. The greenhouse environment model, based on energy and mass balance principles, was implemented in a web-based interactive application that allowed for the selection of the greenhouse design, weather conditions, and operational strategies. The greenhouse environment simulator was designed to be used as an educational tool for demonstrating the physics of greenhouse systems and environmental control principles. Several scenarios were simulated to demonstrate how a specific greenhouse design would respond environmentally for several climate conditions (four seasons of four geographical locations), and to demonstrate what systems would be required to achieve the desired environmental conditions. The greenhouse environment simulator produced realistic approximations of the dynamic behavior of greenhouse environments with different design configurations for 28-h simulation periods.

Grafting of vegetable seedlings is a unique horticultural technology practiced for many years in East Asia to overcome issues associated with intensive cultivation using limited arable land. This technology was introduced to Europe and other countries in the late 20th century along with improved grafting methods suitable for commercial production of grafted vegetable seedlings. Later, grafting was introduced to North America from Europe and it is now attracting growing interest, both from greenhouse growers and organic producers. Grafting onto specific rootstocks generally provides resistance to soilborne diseases and nematodes and increases yield. Grafting is an effective technology for use in combination with more sustainable crop production practices, including reduced rates and overall use of soil fumigants in many other countries. Currently, over 40 million grafted tomato seedlings are estimated to be used annually in North American greenhouses, and several commercial trials have been conducted for promoting use of grafted melon seedlings in openfields.Nevertheless, thereareissuesidentifiedthatcurrently limitadoptionofgraftedseedlings inNorthAmerica. One issue unique to North America is the large number of seedlings needed in a single shipment for large-scale, open-field production systems. Semi- or fully-automated grafting robots were invented by several agricultural machine industries in the 1990s, yet the available models are limited. The lack of flexibility of the existing robots also limits their wider use. Strategies to resolve these issues are discussed, including the use of a highly controlled environment to promote the standardized seedlings suitable for automation and better storage techniques. To use this technology widely in North American fresh vegetable production, more information and locally collected scientific and technical data are needed. Grafting of herbaceous seedlings is a unique horticultural technology practiced for many years in East Asia to overcome issues associated with intensive cultivation using limited arable land for vegetable pro- duction. According to Lee and Oda (2003), a self-grafting technique to produce a large gourd fruit by increasing root-to-shoot ratio through multiple graftings was described in an ancient book written in China in the 5th century and in Korea in the 17th century. The first record of interspecific, herbaceous graft- ing as a yield increase and pest/disease con- trol strategy was for watermelon (Citrullus lanatus (Thunb.) Matsum.& Nakai), using a squash rootstock (Cucurbita moschata Duch.), reportedly developed by a water- melon farmer in Japan (Tateishi, 1927). This watermelon grafting technique was quickly disseminated to farmers through extension research programs of regional agricultural experimental stations in Japan, and then later into Korea, during the late 1920s and early 1930s. Use of grafted seedlings in commer- cial vegetable production occurred as early as the 1930s in Japan for watermelon grafted on Lagenaria siceraria (Mol.) Standl. (Oda, 2002). Research on grafting cucumber (Cucumis sativus L.) also started in the late 1920s,butwidercommercialapplicationsdid not happen until 1960 (Sakata et al., 2008). For members of the Solanaceae, the first record was of eggplant (Solanum melongena L.) grafted on scarlet eggplant (Solanum integrifolium Poir.) in the 1950s (Oda, 1999). Grafting tomato (Lycopersicon escu- lentum Mill.) was introduced commercially in the1960s(LeeandOda,2003).Alongwiththe rapid development of intensive protected cul- tivation technologies using high tunnels and greenhouses, which presumably prevented farmers from continuing traditional crop rota- tion, vegetable grafting became a crucial tool to overcome soilborne diseases and other pests. In the 1990s, nearly 60% of open fields and greenhouses in Japan producing musk- melon (Cucumis melo L.), watermelon, cucumber, tomato, and eggplant were report- edly planted with grafted seedlings (National Research Institute of Vegetables, Ornamental

Tomato (Lycopersicon esculentumMill., cv. Momotaro) plug transplants were grown in a closed-type (CTPS) and an open-type (OTPS ; i.e., greenhouse) transplant production systems during summer (11-15 August to 1 September, 2000) . The quality of transplants and water consumption in the CTPS were compared with those in the OTPS. Electric energy consumption per transplant was estimated in the CTPS. The CTPS was a system designed to produce transplants under artificial light in a relatively airtight structure with thermally insulated walls, and to produce high quality transplants using minimal resources. The CTPS employed a sub-irrigation system. Air temperature in the CTPS was maintained at 28°C during a 16 h photoperiod and at 19°C during an 8 h dark period by using an air conditioner. The OTPS employed an overhead irrigation system. Air temperature in the OTPS was partly controlled by using roof and side ventilators, but varied from 23 to 43°C depending on the weather conditions. The quality of transplants was higher in the CTPS than in the OTPS. Electric energy consumption per transplant in the CTPS was 0.7 MJ (0.2 kWh), which corresponded to a cost of 2.9-3.2 Japanese Yen. The amount of water consumed during the transplant production period in the CTPS was 1/12-1/16 of that in the OTPS. These results suggested that value-added transplants could be produced at a lower water consumption of resources in the CTPS than in the OTPS at low electricity consumption.

Electric energy consumption for cooling (Wc) and the coefficient of performance for cooling (C) were investigated in a closed-type transplant production system (CTPS). C is defined as the ratio of heat energy absorbed by the evaporator of the air conditioner to Wc. A Basic Module Room with thermally insulated walls (5.8 m (W), 2.7 m (L), 5.4 m (H)) in the Research Unit for Closed Plant Production Systems at Chiba University was considered as a model CTPS. Home-use air conditioners, fluorescent lamps, fans and humidifier were installed in the CTPS. One hundred fifty-one data sets were collected for the analysis during the period from 1 May 2000 to 30 April 2001 when air temperatures inside the CTPS (Tin) during photo-and dark period were 29-31°C and 27-29°C, respectively. The chemical energy assimilated by the transplants was considered to be negligible. In the preliminary study, the number of air exchanges of the system was found to be 0h-1 Heat energy transmission through the walls was estimated as the product of heat transmission coefficient (ceiling and side walls : 0.3 W m-2 k-1 floor : 0.2 W m-2 K-1) and the air temperature difference between inside and outside the CTPS. Subsequently, C was estimated by dividing the heat energy generated inside the CTPS (Q) by Wc. Wc increased with increasing air temperature outside the CTPS (Tout) and with increasing Q. Most (72-86%) of the electric energy was consumed by lamps. The rest was consumed by air conditioners (7-17%) and other equipments (5-15%). The average value of C was 7.6 under this experiment condition. The estimated values of C were 1.1-2.6 times greater in this experiment condition than the catalog value measured in the standard condition (Tin : 27°C, Tout : 35°C), because Tout was lower than Tin. C increased with decreasing Tout and with increasing Q. These results show that C of a recent model of home-use air conditioner is relatively high, and its application is beneficial for reducing Wc in the CTPS.

The energy balance of a commercial scale closed transplant production system was investigated to estimate the energy consumed by the system and to find the optimal strategies of environmental control of the system. The system consisted of a transportation/irrigation machine, four basic modules and thermal insulation wall. The basic module consisted of shelves, lamps, air conditioners, fans and a humidifier. Sweetpotato (IPomoea batatas (L.) Lam. cv. Beniazuma) transplants were grown for 15 days under conditions of 140/200/320μ molm-2s-1 (1-5/6-11/12-15 days after planting, respectively) photosynthetic photon flux with 16h d-1 photoperiod, 28°C air temperature, 74% relative humidity and 990μmol mol-1CO2 concen-tration in the system. The total electric energy consumed by the system during 15 days when four basic modules operated was 764 MJ m-2. The system's lamps, air conditioners, fans, humidifiers and transportation/irrigation machine consumed 78.4%, 10.6%, 7.1%, 0.7% and 3.2% of the total electric energy consumed by the system, respectively. The electric energy cost per transplant, depending on the seasonal electric energy charge, was 2.5-2.6 Yen. The ratio of net chemical energy fixed by transplants to the total electric energy consumed by the system was estimated at 0.006 when the transplants grew normally. The coefficient of performance of the system was 8.0 and about 2 times higher than that described in the catalog of the air conditioner. The maximum percentage of heat energy transported by ventilation and penetra-ted through walls and floor to the cooling load of the system was estimated at 0.18% in summer and -25% in winter.

Modeling and simulation are discussed with regard to their roles in transplant production under controlled environment. Little research has been done toward analysis and optimization of transplant production system based on modeling and simulation. In this article, research on modeling and simulation of growth and development of transplants as well as production scheduling are reviewed. Some models and simulated results are introduced for use in different modes of transplant production (vegetative propagation, plug seedling production, and storage of transplants). Integration of the knowledge of environmental factors affecting transplant growth and development is required for using modeling/simulation techniques as strategic production tools of transplants.

To improve the culture conditions for micropropagation, different types of culture vessels and capping systems have been designed. Some of these designs improve the aerial composition in the culture vessel and some for recycling the nutrient medium. This article describes the evolution of different culture vessel and culture systems, with special emphasis on forced ventilation to improve the culture atmosphere and thus to improve the growth and multiplication and also the quality of propagules. By altering the aerial environment of the culture vessel, plantlets can be grown photoautotrophically (sugar free medium) which has many advantages over the photomixotrophic or heterotrophic system. By using forced ventilation and a photoautotrophic culture system, the scaling-up of the culture vessel is possible with high growth rate and survival percentage and with minimum time and space. More recently, this scale-up system has been further extended making the aseptic culture room itself a large culture vessel containing many small sterile trays with plants on the culture shelves and with a common headspace. By using this enlarged system, the production of even more quality transplants was achieved relatively easily.

We are requested to develop a concept, a methodology and an industry to solve the global issues on environmental pollution and shortages of food, feed, phytomass (plant biomass) and natural resources including fossil fuels and usable water. These issues are considered to become more and more serious on a larger scale in the forthcoming decades. In order to solve those issues in the 21st Century, billions of plants are required every year not only for food, feed and environment conservation, but also for alternative raw materials to produce energy, bio-degradable plastics and many other industrial products. By using plant-derived products, we can minimize the environmental pollution and the use of fossil fuels and atomic power. Then, we need billions of quality transplants (small plants) every year to be grown in the fields with maximum use of solar energy and minimum use of resources under harsh environmental conditions. These quality transplants can be produced only under carefully controlled environments. Bioengineering is expected to provide a useful concept and a methodology to develop the bioindustry for solving the above global issues substantially. In bioengineering, the global and local flows of energy, mass (or materials) and information are analyzed with special attention to the organic and inorganic metabolisms of plants, animals including humans and microorganisms. Concept of ‘closed-type or closed production systems’ is essential to develop a production system with minimum use of resources and with minimum environmental pollution. This concept can be applied to develop a closed-type transplant production system with artificial lighting for producing billions of quality transplants with minimum use of resources and with minimum environmental pollution. Research and development of the closed transplant production systems will create a new field of bioengineering and bioindustry.

Greenhouse technology is expected to contribute significantly to solving four global issues: a shortage of food, a shortage of fuel energy/natural resources, environmental pollution and instability of various ecological systems. These tissues will become increasingly critical in the early 21st century, when the world population is predicted to reach nearly 10 billion. The use of greenhouses will increase considerably in the 21 st century when they will be used producing large varieties and large numbers of transplants, including forestry trees, food crops, industrial crops, bio-fuel plants, and medicinal plants. Disease-free and genetically superior transplants produced in the greenhouse generally give higher yields and show higher quality when transplanted into the field. In order for greenhouses to contribute to solving the above global issues in the next century, research on two important types of greenhouse technology is needed: 1) development of multi-functional, biodegradable film for greenhouse and plant coverings, etc. in the subtropical and tropical regions, and 2) development of transplant production systems that use artificial lighting.

Micropropagation has been an important method for producing a great number of nursery plantlets/transplants used in agriculture, forestry, and horticulture. Recent research has shown that controlling environment is important for producing high quality plantlets with efficient use of energy. In this article, we discuss recent topics in environment control in micropropagation. The first sections in this article include control and measurement of in vitro environment, where their effects on plantlet growth and morphology are summarized. In later sections including, recent topics such as low-temperature storage and mathematical modeling and simulation of in vitro growth are introduced.

Currently, in the United States, the greenhouse industry covers more than 15,000 acres and is supported by a diverse number of firms with employee expertise that includes greenhouse manufacturing, engineering, irrigation, horticulture, IPM, sales, marketing, and business management. The growing greenhouse industry continues to be in need of highly trained undergraduates that have mastered an amalgam of scientific and business concepts necessary to be competitive in today's agricultural marketplace. Using a multidisciplinary approach we are creating a multimedia instrument for utilization in a variety of greenhouse related courses. This instrument ultimately will be available on the web for anyone to access. To ensure that our vision matches need, we have reviewed the courses offered throughout the United States at 1862, 1890, and 1994 land grant institutions. Course information collected includes; college, Dept., title, level, description, website (if available) and instructor e-mail (if available). Interestingly, there are at least 84 courses offering some aspect of greenhouse science in the U.S. Most are offered in Colleges of Agriculture or Engineering, but are housed in 17 diverse Dept.s. Examples include Dept.s of Horticulture; Agronomy and Horticulture; Agricultural Biosystems and Engineering; Plant, Soil, and Entomological Science; and Horticulture, Forestry, Landscape & Parks. This information will be utilized to focus the instructional design phase of the multimedia instrument, to contact current course instructors for feedback, and to frame future development of the resource.

Greenhouse crop production systems have been established throughout the world, including arid and semi-arid regions, to fulfill a market demand of locally grown produce consistently through the year. In these particular regions while they have the advantage of sunshine year-round, production during the summer is a challenge due to elevated air temperatures. Fog systems have proven to be a good economical alternative for evaporative cooling while potentially providing a more uniform environment when compared to fan and pad systems. High-pressure fogging systems equipped with variable frequency drives can be operated at different pressures to meet the varying cooling demands during the day. This feature adds the flexibility of varying the fog flow rate by operating at lower pressures or by changing the number of working fog lines accordingly to the cooling demands. These systems may offer the potential advantage of energy and water saving by operating at a low frequency while providing the proper amount of fog accordingly to the cooling loads. A variable pressure fogging systems operating in the range of 4.8 to 10.3 MPa (700 to 1500 psi) was recently installed in a greenhouse at the University of Arizona Controlled Environment Agriculture Center (UA-CEAC) for the purpose of developing advanced control strategies for optimum greenhouse environments. This study experimentally evaluated the dynamics of air and canopy temperatures, crop evapotranspiration rates, and climate uniformity in the greenhouses working under various fogging system operational pressures and greenhouse side/roof vent opening configurations.

Summary. Plants produce various phytochemicals that are of nutritional and medicinal value to humans. Phytochemicals having antioxidant capacity are drawing increased interest from consumers. Population studies among Americans have consistently demonstrated inadequate consumption of fruit and vegetables. Improving intake of fruit and vegetables has been a major public health effort for many years with minimal success. Given this, it seems opportunistic to consider other approaches to enhance the nutritional quality of the American diet. One plausible approach is the development of fresh produce containing a greater concentration of phytochemicals known to improve health, thus while consuming fewer servings of produce, Americans would still have significant exposure to health-promoting food constituents. Controlled environments provide a unique opportunity to modify the concentrations of selected phytochemicals in fruit and vegetables, yet practical information is limited regarding methods effective in optimizing antioxidant capacity. Our research at the University of Arizona Controlled Environment Agriculture Program has shown that application of moderate salt stress to tomato plants can enhance lycopene and potentially other antioxidant concentrations in fruit. The increase in lycopene in response to salt stress in the tomato fruit was shown to be cultivar specific, varying from 34% to 85%. Although the specific biological mechanisms involved in increasing fruit lycopene deposition has not been clearly elucidated, evidence suggests that increasing antioxidant concentrations is a primary physiological response of the plant to the salt stress. Another experiment showed that low temperature during postharvest increased antioxidant capacity of tomato fruit while it maintained the lycopene concentration. More detailed study in this area is needed including accumulation of antioxidant phytochemicals as affected by environmental conditions during the cultivation and the postharvest. of greenhouse tomato available in U.S. retail markets has increased dramatically during the past decade and now accounts for 37% of the weekly quantity of tomatoes sold in the average U.S. supermarket in 2003 (Cook and Calvin, 2005), where this quantity included produce imported from Mexico and Canada. This suggests that greenhouse tomatoes are preferred in retail sales likely due to the consistent supply and generally higher quality than field grown tomatoes. This trend seems driving neighboring countries more into greenhouse production.