Flower Greenhouse Research Articles

A Comparative Analysis of Sliding Mode and Fuzzy Sliding Mode Controllers for Climate Control Application of a Greenhouse Flower Garden

This paper describes a comparative performance analysis of sliding mode and fuzzy sliding mode controllers for climate control application of a greenhouse flower garden. Various internal and external climate related factors affect the overall growth and health of flowers that needs robust controllers to control the humidity and temperature of the greenhouse flower garden. Review of related works show that for non-linear systems, sliding mode controllers can provide robust performance even though chattering is a major drawback of the controller. A number of approaches are used to solve the chattering problem of sliding mode controllers such as hybrid uses of other controllers along with sliding mode controller. In this paper, sliding mode controller and fuzzy sliding mode controllers are designed and implemented for the specified control application based on the linearized and decoupled model of the system. The performance evaluation has been done for the control problems of reference tracking and disturbance rejection with time domain performance measures of percentage overshoot, settling time and rise time. Accordingly, the overall system has been implemented in MATLAB/Simulink and the simulations for the control problems have been done. Thus, FSMC has got rise time of 5.89min, 10.59min settling time and almost negligible percentage overshoot for indoor temperature at 27°C and humidity at 22g/m3. And for humidity control, the FSMC has got 5.44min settling time and nearly zero percentage overshoot for set point tracking problem. For the disturbance of solar radiation, decrease in outside temperature and fixed set point of 27°C and humidity of 22g/m3, FSMC outperforms SMC. In summary, both quantitative and qualitative results analysis results reveal that fuzzy sliding mode controller (FSMC) outperforms sliding mode controller (SMC) for the indoor temperature and humidity control tasks of both set point tracking and disturbance rejection problems.

PEMANFAATAN GREEN HOUSE KEMBANG HARAPAN UNTUK MENINGKATKAN KEPEDULIAN LINGKUNGAN DI MI MA’ARIF GONDANG WATUMALANG

This study aims to determine the application of the Green House program in science lessons in increasing student awareness of the environment. Green House is a controlled plant growing environment. The development of green houses for horticultural cultivation is very important as a guarantor for the success of growing from environmental influences such as temperature, air humidity, sun intensity, and pests and diseases. The use of greenhouses in plant cultivation is one way to provide an environment that is closer to the optimum conditions for plant growth. The research method used is a qualitative Field Research method, with data collection techniques carried out through observation, interviews and documentation. The analysis techniques are in the form of data collection, data reduction, data display and drawing conclusions. Researchers will search and find data broadly and in-depth regarding the method of utilizing the hope flower green house to increase environmental awareness for the upper class of MI Ma'arif Gondang Watumalang. The use of the Green House is a flower of hope to increase environmental awareness for the upper-class MI ma'arif Gondang Watumalang. The results of this study show an increase as marked by disposing of garbage in its place, picketing the yard of community service for all school residents, and sorting organic or non-organic waste.

Mechanical Design of a system for transplanter based on PLC

At present, the development of potted flower seedling transplanting technology at home and abroad is an important measure to comply with the trend of the high growth rate of potted flower production, solve the existing low productivity problems and promote the modernization of potted flower planting in China. It has a profound influence on the transplanting mechanism of potted flower seedlings which have good stability, easy diffusion, and a good development environment. In the PLC(Programmable Logic Controller) system, the instructions and output of the seedlings and seedlings are input and the manipulator is controlled by the manipulator. The cylinder is driven by the mechanical arm, and the refreshed program order reissues the instruction task. In this design, the greenhouse flower seedling transplanter has the functions of grasping seedlings, transporting seedlings, and placing seedlings. During the transplanting process, PLC software is used to control the air cylinder and various motors to drive each working part, so that the transplanting process can be carried out in order and the precise transplanting of flower seedlings can be completed.

Flower Greenhouse Energy Management to Offer Local Flexibility Markets

Electricity access is strongly linked to human growth. Despite this, a portion of the world’s population remains without access to energy. In Colombia, rural communities have energy challenges due to the National Interconnected System’s (NIS) lack of quality and stability. It is common to find that energy services in such locations are twice as costly as in cities and are only accessible for a few hours every day due to grid overload. Implementing market mechanisms that enable handling imbalances through the flexible load management of main loads within the grid is vital for improving the rural power grid’s quality. In this research, the energy from the rural grid is primarily employed to power a heating, ventilation, and air-conditioning (HVAC) system that chills flowers for future commerce. This load has significant consumption within the rural grid, so handling HVAC consumption in a suitable form can support the grid to avoid imbalances and improve the end-user access to energy. The primary responsibilities of the flower greenhouse operator are to reduce energy costs, maximize flexibility, and maintain a proper indoor temperature. Accordingly, this research proposes a flexible energy market based on the bi-level mixed-integer linear programming problem (Bi-MILP), involving the Agricultural Demand Response Aggregator (ADRA) and the flower greenhouse. ADRA is responsible for assuring the grid’s stability and quality and developing pricing plans that promote flexibility. A flower greenhouse in Colombia’s Boyacá department is used as an application for this research. This study looked at the HVAC’s flexibility under three different pricing schemes (fixed, time-of-use, and hourly) and graded the flower greenhouse’s flexibility as a reliable system.

Molecular characterization of a 'Candidatus Phytoplasma asteris'-related strain (16SrI-B / cpn60UT I-IB) affecting daisies (Argyranthemum spp.) in Mexico

From 2018 to 2019 symptoms consistent with infection by plant pathogenic phytoplasma bacteria were observed in commercial flower greenhouses located in Atlixco, Puebla, Mexico. Two varieties of Argyranthemum spp. plants exhibited symptoms of phyllody, causing serious concerns among farmers. To determine if phytoplasmas were associated with the symptomatic plants, the 16S rRNA-encoding locus (F2nR2 fragment) was amplified by PCR. This revealed that the symptomatic plants collected were infected by a phytoplasma belonging to the aster yellows group (16SrI-B). These results were confirmed and refined by amplification and sequencing of the phytoplasma chaperonin 60 universal target (cpn60 UT). Sequence analysis using the online tool CpnClassiPhyR confirmed that the phytoplasma detected is a member of the 16SrI group, specifically a member of the cpn60 UT I-IB subgroup.. This is the first report of daisies affected by phytoplasma in Mexico, and the first report of the use of CpnClassiPhyR to characterize an unknown phytoplasma strain. The detection of phytoplasmas infecting commercially produced daisies and their characterization provides an impetus for phytoplasma management in Atlixco, a Mexican city for which the production of ornamental plants and cut flowers is of economic importance.

A virtual sensor simulation system of a flower greenhouse coupled with a new temperature microclimate model using three-dimensional CFD

Greenhouse culture, as a high-yield and efficient production technology, has become an important means to increase crop yield and quality. Greenhouse environmental monitoring is a key practice affecting the yield and quality of greenhouse crops. Meeting the growth needs of crops while reducing the cost of environmental monitoring has become an urgent and difficult scientific problem. Sensor technology with the addition of computational fluid dynamics (CFD) technique is a new method for addressing this issue. However, this CFD approach generally cannot monitor the greenhouse environment in real time. This study aims to establish a virtual sensor system based on the external environment of a climate model to form a closed-loop network using a finite volume CFD code (ANSYS FLUENT 19.0). An experiment is conducted on a flower greenhouse, and a 3D transient CFD is implemented including a meshing and turbulence model in the MATLAB interface program. Furthermore, a temperature model based on the external greenhouse environment is established using a regression method from the model, and a virtual sensor model of greenhouse temperature is established using a feedback method. The results show that the simulation satisfied the temperature distribution law, revealing that virtual sensors and physical sensors can work together to monitor the greenhouse environment.

Application of water treatment sludge for obtaining fertile soil

The properties of soil obtained from the sludge of water treatment plants were investigated. A new recipe for obtaining soil from peat, river sand and sludge dehydrated with cotton dust was developed. The obtained soil is well structured, resistant to unfavourable mechanical and physical-chemical impacts. It is recommended for creating lawns, planting sports grounds, squares and road slopes. It can be used for filling landfills of solid municipal waste, for strengthening river banks and reservoirs, for soil protection, as well as for production of fertile soils in horticultural and urban farms, when growing vegetables, berries and flowers in greenhouses. The studied soil expands the range of plant nutrient mixtures, is based on the use of available raw materials, and is not difficult to prepare.

Prior Experience with Food Reward Influences the Behavioral Responses of the Honeybee Apis mellifera and the Bumblebee Bombus lantschouensis to Tomato Floral Scent.

Simple SummaryBees are important pollinators for many agricultural crops. Compared with bumblebees, honeybees are less attracted to tomato flowers. Floral scent usually plays an important role in mediating the foraging behavior of bees, and tomato flowers release special scents. However, little is known about how tomato floral scent regulates the foraging behaviors of these two bee taxa. In the current study, we investigated the foraging behaviors of the widely used pollinator honeybee Apis mellifera and a native bumblebee, Bombus lantschouensis, on tomato flowers to evaluate the potential application of these two bee species for tomato pollination in solar greenhouses. Moreover, we determined whether honeybees and bumblebees show different responses to tomato floral scent and how innate biases and prior experience influence bee choice behavior. We found that naïve bees showed no preference for tomato floral scent but could develop such a preference after learning to associate tomato floral scent with a food reward on the basis of foraging experience or scent-learning procedures. We conclude that scent-learning experiences with food reward can change the innate bias of bees and could be utilized to improve the pollination service efficiency of bees for commercial crops.Bee responses to floral scent are usually influenced by both innate biases and prior experience. Honeybees are less attracted than bumblebees to tomato flowers. However, little is known about how tomato floral scent regulates the foraging behaviors of honeybees and bumblebees. In this study, the foraging behaviors of the honeybee Apis mellifera and the bumblebee Bombus lantschouensis on tomato flowers in greenhouses were investigated. Whether the two bee species exhibit different responses to tomato floral scent and how innate biases and prior experience influence bee choice behavior were examined. In the greenhouses, honeybees failed to collect pollen from tomato flowers, and their foraging activities decreased significantly over days. Additionally, neither naïve honeybees nor naïve bumblebees showed a preference for tomato floral scent in a Y-tube olfactometer. However, foraging experience in the tomato greenhouses helped bumblebees develop a strong preference for the scent, whereas honeybees with foraging experience continued to show aversion to tomato floral scent. After learning to associate tomato floral scent with a sugar reward in proboscis extension response (PER) assays, both bee species exhibited a preference for tomato floral scent in Y-tube olfactometers. The findings indicated that prior experience with a food reward strongly influenced bee preference for tomato floral scent.

Acaricide resistance status and identification of resistance mutations in populations of the two-spotted spider mite Tetranychus urticae from Ethiopia.

The intensive use of pesticides is a common practice for the management of the two-spotted spider mite, Tetranychus urticae, in greenhouses and field farms of Ethiopia. However, incidence of resistance and possible resistance mechanisms in T. urticae populations from Ethiopia have not yet been studied. Here, we assessed the toxicity of various acaricides-bifenazate, abamectin, emamectin benzoate, profenofos, fenbutatin oxide, fenpyroximate, amitraz and chlorfenapyr-on T. urticae populations sampled from six flower greenhouse farms, three strawberry greenhouse farms, one field-grown vegetable farm and two wild populations. In parallel, all populations were screened for known target-site mutations. All tested populations were fully susceptible to bifenazate, abamectin, emamectin benzoate and profenofos, but resistant against fenbutatin oxide and fenpyroximate. Four populations showed considerable levels of resistance against amitraz and one population was resistant to chlorfenapyr. Several target-site mutations were identified in the tested populations, including G119S, A201S, T280A, G328A and F331W/C/Y in acetylcholinesterase and the F1538I and L1024V mutation in the voltage-gated sodium channel. The F1538I mutation was found in eight out of 12 populations, whereas the L1024V mutation was only found in two populations. The H92R mutation in the PSST subunit of complex I and the I1017F mutation in chitin synthase 1 was detected in half of the tested populations. The G326E and I321T mutations in the glutamate-gated chloride channel 3 were also detected, but more rarely, whereas mitochondrial cytochrome b mutations were not detected. The current study revealed multiple resistance patterns in Ethiopian T. urticae populations and together with the wide presence of target-site mutations, calls for the wise use of acaricides in the management of T. urticae in Ethiopia.

Plateau Grass and Greenhouse Flower? Distinct Genetic Basis of Closely Related Toad Tadpoles Respectively Adapted to High Altitude and Karst Caves

Genetic adaptation to extremes is a fascinating topic. Nevertheless, few studies have explored the genetic adaptation of closely related species respectively inhabiting distinct extremes. With deep transcriptome sequencing, we attempt to detect the genetic architectures of tadpoles of five closely related toad species adapted to the Tibetan Plateau, middle-altitude mountains and karst caves. Molecular evolution analyses indicated that not only the number of fast evolving genes (FEGs), but also the functioning coverage of FEGs, increased with elevation. Enrichment analyses correspondingly revealed that the highland species had most of the FEGs involved in high-elevation adaptation, for example, amino acid substitutions of XRCC6 in its binding domains might improve the capacity of DNA repair of the toad. Yet, few FEGs and positively selected genes (PSGs) involved in high-elevation adaptation were identified in the cave species, and none of which potentially contributed to cave adaptation. Accordingly, it is speculated that in the closely related toad tadpoles, genetic selection pressures increased with elevation, and cave adaptation was most likely derived from other factors (e.g., gene loss, pseudogenization or deletion), which could not be detected by our analyses. The findings supply a foundation for understanding the genetic adaptations of amphibians inhabiting extremes.

Methodological aspects related to biological assessment of insectoacaricides on flower cultures of protected ground

Relevance. Analysis of the present range of pesticides that are used in flower orangeries showed critical shortage of allowed pesticides. Now there are no methods for registration testing of insecticides designed to protect flowers in greenhouses. Thus, the purpose of our research is to develop methodological approaches to assessment of abundance of major pests for flower cultures of protected ground and determination of biological effectiveness of new insectoacaricides.Methods. The following phytophages represent flower pests that are predominant in the protected ground: aphids: green peach – Myzus persicae Sulz., melon and cotton – Aphis gossypii Glov., greenhouse-potato – Aulacorthum solani Kalt., potato – Macrosiphum euphorbiae Thom., green rose – Macrosiphum rosae Linn.; whiteflies: greenhouse whitefly – Trialeurodes vaporariorum Wstw., silverleaf whitefly – Bemisia tabaci Genn.; thrips: tobacco – Thrips tabaci Lind., rose – Th. fuscipennis Hal., western flower – Frankliniella occidentalis Perg., heterophagous – F. intonsa Tryb., greenhouse – Heliothrips haemorrhoidalis Bouche; mites: red spider – Tetranychus urticae Koch.; red greenhouse – T. cinnabarinus BoisdResults. Researches related to assessment of abundance of major pests for flower cultures and choosing methods related to determination of biological effectiveness of insectoacaricides were performed in flower orangeries of Leningrad Region on hybrid tea roses Rosa L., chrysnatemums Chrysanthemum L., gerberas Gerbera G. As a result, the algorithm for performing tests related to study of new insectoacaricides on flower cultures in greenhouses is developed. Methodology instructions that we offer for assessment of abundance of major pests for flower cultures of protected ground and determination of biological effectiveness of new insectoacaricides are intended for ensuring the uniform methodological approach to performance of registration tests of modern means to fight against these pests and opportunity for analysis of tests in various agroclimatic areas and obtaining a reasonable general conclusion and findings related to pesticides taking into account international requirements.

Considerations for cholinesterase biomonitoring in flower and ornamental plant greenhouse workers

Flower cultivation in greenhouses enhances productivity and ensures high-quality product supply throughout the year. However, under such protected environments, climate conditions are designed to favor flower growth and can intensify occupational exposure to pesticides. In this study, flower greenhouse workers were tested for cholinesterase inhibition, a valuable indicator of occupational exposure to organophosphate and carbamate pesticides. The quantified inhibition was also associated with working practices using these outcomes to explore ways in which provisions of regulatory Occupational Health Control Programs can be met considering the peculiarities of this working environment. Despite their preliminary nature, and considering that workers had not been previously tested, the obtained results suggested that the designed pre- and post-screening process, enabled biomonitoring of the exposed population. The pre-exposure sample was collected after 11 days from pesticide spraying and the post-exposure sample was collected no later than 10 days after pesticide spraying. AChE activity was significantly depressed in flower greenhouse workers, comparing pre- and post-exposure intervals. Nursery workers, often overlooked, presented greater inhibition of AChE activity. Such finding is consistent with effects believed to be associated with the described job and the way activities are conducted, once nursery workers are regularly exposed to low levels of pesticides owing to their continuous contact with sprayed crops. As predicted by Occupational Safety and Health Standards, establishing biomonitoring programs is achievable, despite the intensive use of pesticides. Quantification is important to target the exposed population but is not sufficient to assure good working conditions and avoid exposure. Administrative and working practices, such as job misclassification, non-compliance with national regulations for occupational health control, pesticide handling, lack of REI protocols, and unsuitable delivery of PPE, must be addressed. Anything less will contribute to worsening an already bleak picture in terms of occupational safety and health in flower and ornamental plant greenhouses.

Analysis of the Possibilities of Using a Heat Pump for Greenhouse Heating in Polish Climatic Conditions—A Case Study

This article presents an analysis of selecting a seasonal heating system for an existing greenhouse. The analyzed object is located in Poland near Wroclaw, where summer flowers are grown. Appropriate thermal conditions must be ensured continuously for four heating months. The primary source of heat in the examined flower greenhouse was a coal-fired furnace. The analysis presented in the article shows a method of thermal balancing the object, determining heat demands in the analyzed period using the experiment plan, and also selecting a new heating system in the form of a heat pump. The analysis of the operation of the heating system was performed for air and ground source heat pumps to determine the profitability of their application in Polish climatic conditions. An economic analysis was also included and the investment impact on pollution emissions was calculated.

Repellent, oviposition-deterrent and egg-hatching inhibitory effects of some plant essential oils against citrus mealybug, Planococcus citri Risso (Hemiptera: Pseudococcidae)

The citrus mealybug (Planococcus citri) is a serious pest of citrus groves in Turkey and has recently caused considerable damages to some cut flowers (especially, roses and orchids) in greenhouses in Antalya (southwestern Turkey). In this study, repellent and oviposition-deterrent activities of essential oils from anise (Pimpinella anisum), rosemary (Rosmarinus officinalis), peppermint (Mentha piperita), Turkish oregano (Origanum onites) and thyme (Thymus vulgaris) were investigated against female adults of P. citri under laboratory conditions. The results from the study showed that all the essential oils tested had a repellent activity in varying degrees, and the repellency was concentration and time dependent. Based on the highest dose (5 mL/L water) and the longest time period after the insect introduction (96 h), the oils from O. onites and T. vulgaris had the highest percent repellency in both choice and no-choice tests (O. onites: 88.9 and 65.4%; T. vulgaris: 88.8 and 69.6%, respectively), and followed by P. anisum (80.1 and 50%) and R. officinalis (57.1 and 45.2%) oils. In the oviposition deterrency assays using the highest concentration (5 mL/L water), O. onites essential oil showed the most potent oviposition deterrency (63.7%) resulting in the lowest mean number of eggs laid by the mealybug females (48.8 eggs per female) followed by P. anisum (56.9%). Furthermore, these two oils had the most potent egg-hatching inhibitory effects and inhibited egg hatching by 59.2 and 46.8%, respectively. Overall results suggest that the essential oils tested may help for us in controlling P. citri populations in various agroecosystems.

FPGA Alarm System Based on Multi Temperature Sensor

The purpose of this study is to achieve real-time acquisition and monitoring of temperature in large-scale industrial or agricultural production scene, and timely detect abnormal temperature. FPGA chip, multi temperature sensor and alarm control module three parts consist of FPGA alarm system obtained based on multi temperature sensor. Multi temperature sensor is used for the acquisition of relevant temperature signal in the production site, and the transmission of the collected data through the way of digital signal chip to the FPGA chip for further processing. The FPGA chip is responsible for the parameter setting, the temperature signal acquisition and the threshold comparison and so on, and according to the data processing result, it can send out the normal response control signal to the alarm module. The alarm module contains the pre-warning lights and the alarm device that it can receive the control signal and realize alarm response. The results showed that the test in planting flowers in greenhouse showed that the system is sensitive in response and small in error of temperature acquisition, in accordance with the requirements for use. As a result, the system can be widely used in the temperature monitoring in the production scene, suitable for being promoted in a variety of occasions needing for monitoring the temperature.

Multi-Input Convolutional Neural Network for Flower Grading

Flower grading is a significant task because it is extremely convenient for managing the flowers in greenhouse and market. With the development of computer vision, flower grading has become an interdisciplinary focus in both botany and computer vision. A new dataset named BjfuGloxinia contains three quality grades; each grade consists of 107 samples and 321 images. A multi-input convolutional neural network is designed for large scale flower grading. Multi-input CNN achieves a satisfactory accuracy of 89.6% on the BjfuGloxinia after data augmentation. Compared with a single-input CNN, the accuracy of multi-input CNN is increased by 5% on average, demonstrating that multi-input convolutional neural network is a promising model for flower grading. Although data augmentation contributes to the model, the accuracy is still limited by lack of samples diversity. Majority of misclassification is derived from the medium class. The image processing based bud detection is useful for reducing the misclassification, increasing the accuracy of flower grading to approximately 93.9%.

Characteristics and simulation of rainfall runoff and nitrogen&phosphorus outputs in facil-ity agricultural area:A case study of flower greenhouse region in the East Coast of Lake Dianchi

Characteristics and simulation of rainfall runoff and nitrogen&phosphorus outputs in facil-ity agricultural area:A case study of flower greenhouse region in the East Coast of Lake Dianchi

Molecular epidemiology of Impatiens necrotic spot virus on greenhouse ornamental plants in a local area of Japan

Impatiens necrotic spot virus (INSV), belonging to the genus Tospovirus, causes severe damage to greenhouse ornamental plants. We conducted population genetic analyses of INSV isolated from various greenhouse flowers in Iwate Prefecture as a model to elucidate how the virus invaded and spread within a local area of Japan. Forty-two and 30 sequences of the nucleocapsid protein gene (NG) and intergenic regions (IGR), respectively, of the small RNA of the virus were generated from 42 isolates collected from seven greenhouses in three districts, and then they were divided into 10 NG haplotypes and 13 IGR haplotypes. A combined haplotype analysis for the two loci revealed the presence of 14 NG/IGR haplotypes in the region. Genetic structure of the INSV population based on the NG sequences was differentiated according to districts and greenhouses, and 3 major NG haplotypes were predominant in each district. Genetic analysis based on IGR sequences showed that the population structure in some greenhouses consisted of 1 major IGR haplotype and some minor haplotypes with the same NG haplotype. Phylogenetic analysis based on NG and IGR sequences illustrated that INSV haplotypes were clustered according to geographic origin, including the isolates previously reported in Japan and other countries. Host species did not seem to influence the genetic structure of the INSV population. These results suggest that some founder isolates were introduced individually from other epidemic regions to each district in the region through different routes and then spread within the local areas and greenhouses.

Three years experimental comparative analysis of a desiccant based air conditioning system for a flower greenhouse: Assessment of different desiccants

This paper presents three years experimental comparative analysis of a desiccant-based and a traditional air conditioning system for a flower greenhouse in the winter season. Two identical neighbouring flower greenhouses were equipped with a traditional and an innovative air conditioning system respectively. The innovative air conditioning system is based on the Ventilated Latent Heat Converter (VLHC) AGAM 1020 that consists of a dehumidification and a regeneration unit. Heat recovery is performed on the desiccant regeneration process to warm up the dehumidified air coming back into the greenhouse.Comparative analysis was carried out for three years using three different desiccants in the VLHC: H2O/LiCl in 2010, H2O/KCOOH in 2011 and H2O/LiBr in 2012. The greenhouse equipped with a sorption unit exhibits an energy saving of 9.6% in 2010, 11.7% in 2011, and 15.1% energy saving in 2012. The comparative analysis gives the opportunity for the assessment of the hygroscopic salt solutions currently used as desiccants. Although H2O/LiBr desiccant exhibits the best performance, the solution H2O/KCOOH seems to be very promising as “desiccant of the future”.

Dust, endotoxin, fungi, and bacteria exposure as determined by work task, season, and type of plant in a flower greenhouse.

Greenhouse workers are exposed to dust, endotoxin, fungi, and bacteria potentially causing airway inflammation as well as systemic symptoms. Knowledge about determinants of exposure is a prerequisite for efficient prevention through knowledge-based reduction in exposure. The objective of this study was to assess the occupational exposure in a flower greenhouse and to investigate the impact of work tasks on the intensity and variability in exposure. Seventy-six personal full-shift exposure measurements were performed on 38 employees in a Danish flower greenhouse producing Campanula, Lavandula, Rhipsalideae, and Helleborus. The samples were gravimetrically analysed for inhalable dust. Endotoxin was assessed by the Limulus Amoebocyte Lysate test and culture-based quantification of bacteria and fungi was performed. Information on the performed tasks during sampling was extracted from the greenhouse electronic task logging system. Associations between log-transformed exposure outcomes, season, and work tasks were examined in linear mixed-effects regression with worker identity as random effect. Measured concentrations ranged between 0.04 and 2.41mg m(-3) for inhalable dust and between 0.84 and 1097 EU m(-3) for endotoxin exposure, with the highest mean levels measured during Lavandula and Campanula handling, respectively. Personal exposure to fungi ranged between 1.8×10(2) and 3.4×10(6) colony-forming units (CFU) m(-3) and to bacteria between 1.6×10(1) and 4.2×10(5) CFU m(-3). Exposure to dust, endotoxin, fungi, and bacteria differed between seasons. Packing Lavandula, sticking, potting, and grading Rhipsalideae, and all examined tasks related to Campanula production except sticking increased dust exposure. Endotoxin exposure was increased during sticking Campanula and pinching or packing Rhipsalideae, and fungi exposure was elevated by subtasks performed in the research and development area for Campanula, and by potting, packing/dumping Campanula. Sticking and working with subtasks in the research and development area for Campanula increased bacteria exposure. This study revealed moderate dust exposure levels compared to the levels observed in other greenhouse productions and other occupations with organic dust exposure such as farming. However, high exposures to bacteria and fungi were detected during selected tasks and the proposed health-based endotoxin exposure limit of 90 EU m(-3) was exceeded in 30% of the samples, which may have health implications for the employees. Exposure levels were found to vary depending on the tasks performed, and thereby results can be used to direct task-based initiatives to reduce workplace exposures.