In recent years, transient expression systems in plants have emerged as an attractive platform for recombinant protein production. Green fluorescent protein (GFP) is widely used as a reporter; however, its expression changes over time, highlighting the need for a practical, non-destructive method to monitor expression dynamics. Here, we developed an image-analysis method to evaluate GFP expression in cucumber (Cucumis sativus L.) cotyledons infected with a GFPexpressing cucumber mosaic virus (CMV) vector. Cotyledons were illuminated with blue light-emitting diodes (peak wavelength, 480 nm) to excite GFP, and fluorescence images were acquired using a digital camera equipped with a bandpass filter (500-800 nm). Images were binarized to segment regions with detectable fluorescence, and the fluorescent area was quantified. The fluorescent area estimated by image analysis showed a moderate positive correlation with GFP levels measured by ELISA (p < 0.01, R = 0.71). During the first three days after infection, fluorescence remained localized near the inoculation site, suggesting cell-to-cell or short-distance movement. In contrast, the fluorescent area increased markedly by day 6 under high photosynthetic photon flux densities (500 and 1000 mu mol m(-2 )s(-1)), whereas this increase was delayed until day 9 under low PPFD (100 mu mol m(-2 )s(-1)). These increases may reflect long-distance movement through the phloem. Although further improvement is needed to reduce noise (e.g., fluorescence originating from necrotic tissue), this method provides a simple, non-destructive means to monitor GFP-expressing areas in plants. It may facilitate optimization of recombinant protein production.
Pollination services play an important role in global food production. This study advances an agent-based simulation that reproduces the flower-visitation process in which pollinators search for flowers using floral volatile compounds as cues. In particular, we develop theory for (i) the representativeness of an agent with respect to the number of pollinators it denotes in the simulation and (ii) the conversion between simulation and real-world spatiotemporal scales. We show that these scales can be converted from the representativeness of agent and flower counts within the simulation. As an example, when an agent represents one pollinator and an attractant source represents one flower, the results convert to 24% of total attractant consumed in 84 s. This study is expected to help realize the quantitative evaluation, via simulation, of the impacts of environmental change on pollination services.
This study, using semantic segmentation, compared the performance of forest damage detection between aerial, Sentinel-2 and World View-2 (WV2) images, which differ in terms of ease of image acquisition and spatial resolution. In the case of high-resolution aerial images, forest damage can be detected more accurately by semantic segmentation than by conventional maximum likelihood classification. The study conducted segmentation in two stages: segmentation of normal and damaged areas and segmentation of landslides and fallen trees from the damaged area. Two-stage segmentation demonstrated better performance than three-class segmentation. Through the segmentation processes, class weights were applied to mitigate differences in the number of pixels in each category. Although the performance of the segmentation in the Sentinel-2 images was not comparable to that of aerial images, the segmentation appeared to be useful for a rapid and rough estimation of the damaged area. WV2 images can be used as alternatives to aerial images. In the segmentation with aerial and Sentinel-2 images, the network trained at a certain site could be used for another site without any additional training for another site, or with training using a small number of other site images.
This study evaluated a low-cost, closed-loop freshwater recovery system employing hydroponically grown lettuce (Lactuca sativa L.) irrigated with either a standard nutrient solution or a recycled nutrient solution derived from biogas digestate aerobically nitrified (hereafter, nitrified biogas digestate). The system operated under natural sunlight, enabling examination of the effects of solar radiation fluctuations, air temperature, vapor pressure deficit (VPD), CO2 concentration, and irrigation water quality on water transfer, recovery efficiency, and plant performance. Diurnal monitoring and regression analyses demonstrated strong positive correlations of radiation, temperature, and VPD with water transfer and harvest rates (R-2 > 0.82), whereas elevated CO2 concentrations correlated negatively with transpiration-driven fluxes. Despite the higher salinity and osmotic load of the nitrified biogas digestate (EC = 6.8 dS m(-1); psi(s) = 0.277 MPa, where psi(s) denotes the solute potential), water fluxes, recovery efficiency, and biomass production remained comparable to those with the standard nutrient solution. Lettuce sustained stable physiological activity under moderate salinity stress, with condensation recovery efficiencies exceeding 80% in planted systems versus 63.8% in the non-vegetated control. Condensation reduced the electrical conductivity of the recovered water to 0.01 dS m(-1) and restored a near-neutral pH, confirming the effectiveness of vapor-phase purification. Overall, the results demonstrate the potential of plant-based, sunlight-driven hydroponic systems combined with nitrified biogas digestate for sustainable freshwater recovery and reuse in closed, resource-limited environments.
This study examines labor-saving methods for creating training data in the construction of a deep learning model for fruit detection. The study examined the relationship between the number of training images required for normal training and detection accuracy for peaches and grapes. The results of the normal training were used as a reference to examine the other methods, a method based on training between different fruit species, ones using fruit model images, and the effect on accuracy of the presence or absence of background was also compared. In the normal training, accuracy was achieved with around 200 images, and the effect of further increases was limited. Furthermore, in the learning of interspecific fruits, it was demonstrated that even learning model trained on different species can achieve high detection accuracy if it can utilize image data of a small number of target fruit species. The combination of learning with fruit replica images and fine tuning with a small amount of real images was shown to achieve high accuracy while reducing the dependence on the real environment. These results contribute to labor-saving fruit detection using deep learning.
This study evaluated the characteristics of 3D point cloud generation for estimating leaf area in floricultural crops using a smartphone-based scanning method. Focusing on stock (Matthiola incana (L.) R. Br.), a key winter-season flower cultivated in Namie Town, Fukushima Prefecture, we investigated the influence of scanning conditions, specifically the distance between the camera and the plant, and the number of scanning laps, on the accuracy of leaf area estimation. An iPhone 12 Pro with the Scaniverse application was used to acquire 3D data of a single stock plant grown under controlled greenhouse conditions. Multiple 3D models were generated by varying the camera-to-subject distance (5-40 cm) and scanning laps (1-7), and these were compared against a reference model obtained through extensive scanning. To evaluate model quality, the generated point clouds were registered to the reference model. Individual leaves were segmented, meshed, and their surface areas calculated. Absolute Percentage Error (APE) and Mean APE (MAPE) were used as accuracy metrics for individual and total leaf area estimation, respectively. Results showed that increasing the scanning distance (up to 40 cm) and using a moderate number of laps (up to 5) reduced missing parts on point clouds and improved leaf area estimation accuracy. Although shorter distances yielded denser point clouds overall, the narrower field of view resulted in incomplete capture of outer leaves, leading to reduced accuracy. These findings highlight the importance of optimizing scanning distance and lap number to minimize point cloud loss and enhance estimation performance. This approach offers a practical and non-destructive solution for plant phenotyping using widely accessible smartphone devices.
Gluten-free rice flour is used in food processing. The quality of the product during storage may be influenced by intrinsic properties and environmental factors such as temperature, humidity, and oxygen exposure. Indica rice, mainly grown in the tropics, is long, slender, and high in amylose than other varieties. In this study, we investigated the changes in the physicochemical properties of Indica rice flour under varying hermetic conditions; ambient, vacuum, CO2-filled, and bagged during storage at 30 degrees C for 3 months, aiming to identify an economically viable storage approach for tropical regions. The moisture content decreased over the observed period. The apparent amylose content remained relatively unchanged. The water absorption index, water solubility index, and swelling power index exhibited a rapid increase in the initial month and then steadied with slight upward fluctuations. Catalase activity and pH, showed that stored flour deteriorated gradually over time. The storage conditions significantly affected the moisture content and pH values but storage time had a greater influence on all measured parameters. The ambient storage condition effectively minimized moisture loss and pH decline over three months, offering a cost-effective storage solution ideal for low-income farmers in the tropics.
Promoting tourism resources are important issue for local governments. In this study, Akima Bairin, or Akima plum grove, which is famous for its plum blossoms, in Annaka City, Gunma Prefecture, was selected as a study site. We created a 53-second tourism PR video including 3D models using aerial photos and videos taken by a small drone, which have become increasingly popular in recent years. 3D reconstruction software was used to build 3D models and also create animations. Then, we investigated the advantages of this method. Aerial video captured by a small drone enabled a dynamic expression which was different from the viewpoint from the ground. Also, by using 3D models, the viewpoint movement which was not actually recorded in situ can be simulated. The methods presented in this study can be used to create PR videos promoting local natural tourism resources.
Although previous research has explored the use of saline water or biogas digestate for irrigation in closed systems, the effects of varying salinity levels on water transfer and harvest rates under different leaf area index (LAI) conditions have not been fully investigated. This study assessed the potential of saline water desalination by examining water transfer (evapotranspiration) and harvest rates across three distinct salinity levels and four LAI conditions in a closed lettuce culture system. Simultaneously, water quality parameters, including electrical conductivity (EC) and hydrogen ion concentration (pH), of the harvested water were analyzed. Water transfer and harvest rates increased with increasing LAI, independent of salinity level, despite a reduced water vapor pressure deficit (VPD) within the closed system. Simulations indicated that these rates would be significantly higher if the VPD level remained constant (e.g., 1 kPa). The water harvest rate was approximately 80% of the water transfer rate, with the difference between water transfer and harvest rates attributed to system ventilation. To achieve higher water harvest rates, a more airtight system is necessary, along with maintaining CO2 concentrations at or exceeding atmospheric levels (approximately 500 mu mol mol(-1)) to prevent growth inhibition at higher LAI conditions. In addition, the EC and pH of the harvested water were significantly lower than those of the irrigated saline water, indicating the potential of using plants for water desalination in a closed system. The results provide fundamental quantitative data for harvesting freshwater and plants from saline water in closed plant culture systems.
In recent years, the use of biostimulants, which include substances and/or microorganisms that enhance plant physiological functions, has gained increasing attention in agriculture. A biostimulant composed primarily of naturally occurring rare fatty acids is currently used as a growth promoter in some plant production systems. This study investigated the effects of foliar application of LEAFENERGY (R) by comparing changes in the photosynthetic rate, transpiration rate, and stomatal conductance of mature greenhouse-grown tomato leaves. The upper leaf surfaces were sprayed with 600 mu L of a 600-fold dilution of LEAFENERGY (R) solution, and control leaves were sprayed in the same manner with an equivalent volume of water. The photosynthetic rate and stomatal conductance were greater in the biostimulant-treated leaves than in the control leaves, suggesting that treatment with the biostimulant promoted photosynthesis by opening the stomata and increasing gas exchange. The sugar content of the biostimulant-treated leaves also increased, likely due to the promotion of photosynthesis.
Green onions ( Allium fistulosum L.) are an essential flavoring vegetable in Asian cuisine with high nutritional value. To ensure their stable future production, efficiently cultivating them in plant factories is necessary. In this study, we investigated the effects of spectral photon flux density and lighting position and direction for green onion production using two cultivars ( ` White Star ' and ` Fukuichi-Negi ' ). First, we investigated the effects of four types of light -emitting diode (LED) lamps with or without far -red light and different red/blue (R/B) ratios on the growth of the green onion cultivars. ` White Star ' had the highest shoot fresh weight when grown under low blue -light ratio LED lamps with far -red light, while ` Fukuichi-Negi ' had the highest shoot fresh weight under medium blue -light ratio LED lamps. The R/B ratio and far -red light affected green onion growth, with the effect varying among the varieties. Furthermore, we investigated a light irradiation method to increase the production efficiency of green onions. We compared the growth of the two green onion varieties by irradiating the top of the plants (conventional method) or their sheath base from the lateral direction (sideward irradiation). The results showed that the shoot fresh weight of ` White Star ' and ` Fukuichi-Negi ' grown under sideward irradiation were 1.5- and 1.3 -fold higher than those under the conventional method, respectively. This study provides important knowledge for improving the efficiency of green onion production in plant factories using LEDs.
To investigate effects of CO2 concentration, light intensity, and nutrient solution strength on the growth of wasabi (Eutrema japonicum (Miq.) Koidz.) seedlings, they were grown in environmentally controlled chambers. In the first experiment, single effect of CO2 concentration on growth of wasabi cultivar 'Izuma' was investigated. The dry weight of the whole seedling was increased more under enriched CO2 concentrations (1000 and 2000 ppm (v/v)) than under ambient CO2 concentration (400 ppm). However, the CO2 effect to raise photosynthesis was weakened in the latter half of the experiment. To sustain the effect of the enriched CO2 throughout the whole seedling cultivation period and maximize the wasabi seedling growth, the wasabi seedlings were grown under different light intensities and different nutrient solution strengths in the second experiment. Two wasabi cultivars 'Izuma' and 'Fujimidori' were used. 'Fujimidori' is a newly developed cultivar that is more tolerant to high temperatures. The results revealed that 'Fujimidori' had the highest whole dry weight under enriched CO2 concentration (1000 ppm), higher light intensity (200 mu mol m(-2 )s(-1)), and higher concentration of the nutrient solution. Contrary, the whole dry weight of 'Izuma' under such environmental conditions was almost the same as that of 'Izuma' grown under a lower concentration of nutrient solution but enriched CO2 concentration and higher light intensity, and under lower light intensity but enriched CO2 concentration and higher concentration of nutrient solution. This suggests that a combination of a higher concentration of the nutrient solution and higher light intensity cannot amplify the CO2 effect on 'Izuma' growth. The difference in the environmental response between the two cultivars seemed to be partially caused by the different temperature tolerances.
Seed-propagated strawberry ` Yotsuboshi ' is capable of flower bud differentiation under short-day and low-temperature conditions, which promotes flower bud differentiation in June-bearing varieties, as well as under 24-hour light period. In this study, we hypothesized that overnight supplemental lighting during the nursery period could induce flowering and promote growth of ` Yotsuboshi ' . We investigated the effects of photosynthetic photon flux density (PPFD) and light quality of overnight supplemental lighting on growth and flowering of ` Yotsuboshi'. Blue, green, and red light-emitting diodes (BGR_LED) or blue, red, and far-red LEDs (BRFR_LED) were used as supplemental light sources. Overnight supplemental lighting was conducted from 18: 00 to 6: 00 hours at 100, 200, and 300 mu mol m(-2) s(-1) PPFDs on the canopy of seedlings for 30 days during the summer season in Japan. At 15 and 30 days after initiating treatment, the dry weights of plants in all treatments with supplemental lighting were >1.5-times higher than those in the control without supplemental lighting. There was no significant difference in the total dry weight between the different supplemental light sources at each PPFD. The number of days from the start of the treatment to flowering was less than 50 for plants that received supplemental lighting with BRFR_LED than those for plants without supplemental lighting (control). Therefore, overnight supplemental lighting should include far-red light to promote flowering in ` Yotsuboshi'.
I have been studying material circulation in closed systems, including CELSS (Closed/Controlled Ecological Life Support System), from an engineering standpoint. This paper reviewed our research. First, we applied autonomous decentralized control to the CELSS material circulation system. Next, I constructed a mathematical model of a microcosm, the smallest ecosystem, and explored the causes of its stability. Around the same time, I helped to develop a method for creating operating procedures for material circulation systems using an automatic scheduling method. Based on these experiences, I proposed a hierarchical control method. As an additional function to this method, I added a function to automatically determine the order in which to repair multiple faulty machines.
With the aim of effectively utilizing north sea urchins removed from the sea-urchin barren grounds and reducing food waste, the feeding value of discarded fried chicken and rice balls from a convenience store for north sea urchins was examined. After 56 days of rearing, a comparison of gonad index, gonad coloration, taste, and free amino acid content in north sea urchins revealed that when fed with diets adjusted from fried chicken, their gonads exhibited a relatively bright yellow coloration, but were accompanied by a higher content of valine and methionine, resulting in a pronounced bitterness. In contrast, when fed with diets adjusted from rice balls, although the gonad indexes were smaller in size, the gonads had a sweet taste without bitterness, and there was a minimal amount of remaining food. When fed diets comprising equal amounts of rice balls and fried chicken, the north sea urchins exhibited higher gonad indexes, mitigating color and taste shortcomings observed when each diet was provided individually. Based on the above results, it is considered that these two types of food waste can be potentially utilized as suitable feed for north sea urchins by either mixing them or, if mixing is not feasible, providing fried chicken to enhance gonad indexes, followed by rice balls to improve taste. This approach may enhance the utilization of north sea urchins by either mixing them or, if mixing is not feasible, providing fried chicken to enhance gonad indexes, followed by rice balls to improve taste. Such approaches may contribute to optimizing the utilization of north sea urchins with waste as an advantageous feed source.
Insect pollination is one of the most widely used methods in greenhouse horticulture. An efficient pollination service minimising external energy input is essential to realise carbon-neutral and self-sufficient greenhouse system. In this study, we developed a preliminary model for simulating the dynamics of pollination process to contribute to the future establishment of energy-efficient pollination services for sustainable practices in greenhouse cultivation. The model assumes that pollinators are attracted by the VOCs emitted from pollen grains and that pollen are consumed by the pollinators. Our results demonstrate significant variations in pollination efficiency based on the distribution of plant species within a field. Further research on pollinator behaviour and the dynamics of attractants from plants is necessary to refine the model.
A temporally closed-chamber system was developed to measure the photosynthesis and transpiration of whole ornamental plants in an indoor environment. The chamber system employs the closed-chamber method to measure the photosynthesis and transpiration of the experimental plant within the chamber. This is achieved by temporarily halting the ventilation fan. Subsequently, by activating the ventilation fan, the chamber's environment is restored to match the external conditions. Utilizing this chamber, the photosynthetic rate, transpiration rate, and total conductance of five Everfresh (Cojoba arborea var. angustifolia) plants under varying light-intensity conditions were assessed. The results revealed significant variability in the light response of photosynthesis, transpiration, and total conductance among the five ornamental plants, despite their common origin from the same grower. This variation in light responses is likely attributed to differences in growing conditions. The findings imply that specific management guidelines tailored to the light response of photosynthesis and transpiration should be established for each ornamental plant to ensure its well-being in an indoor environment.
We investigated the soil nutrient conditions of commercial broccoli fields and evaluated them for fertilization improvement using Low-PK fertilizers (those fertilizers which contain lower P and K than N) over two years in field experiments. Continuous cropping of broccoli may result in higher phosphate and potassium content and a disruption of the base balance, and potentially cause environmental pollution. Therefore, the relationship between excessive soil nutrients and the use of Low-PK compound fertilizers was investigated to evaluate the appropriate method and conditions for improved plant growth. The results suggest that we can improve the excessive accumulation of nutrients and base balance using a combined Low-PK fertilizer and drip irrigation in broccoli fields. This fertilization method may help address the nutrient environment for optimal broccoli growth while also being effective for high-quality vegetable management and improvement in soil nutrient conditions for broccoli cultivation.
The influences of quercetin on the productions of lipid peroxides, anisidine-reactive compounds and ozone in autoxidation of alpha -linolenic acid were investigated. Lipid peroxide concentration, anisidine value and ozone concentration significantly increased in the autoxidation of alpha -linolenic acid for 5 days. On the other hand, the addition of quercetin as a natural antioxidant agent efficiently suppressed the increases in the generations of these peroxidation products. The increase in ozone concentration was correlated with the increase in anisidine value, but not the lipid peroxide concentration. The oxidative cleavage of double bonds in alpha -linolenic acid and lipid peroxides by ozone generated in the autoxidation seems to be involved in the productions of anisidine-reactive compounds. Quercetin inhibited the process of productions of anisidine-reactive compounds by inhibiting the generation of ozone from lipid peroxides. Next, the direct effect of autoxidized alpha -linolenic acid on A DNA was evaluated. The autoxidized alpha -Linolenic acid degraded A DNA dependently upon the increase in anisidine-reactive compounds. On the other hand, the addition of quercetin during the autoxidation of alpha -linolenic acid significantly inhibited the degradation of A DNA. 2,4-Heptadienal and trans -2-pentenal efficiently degraded A DNA, suggesting that the DNA -degrading compounds in autoxidized alpha -linolenic acid might be these aldehydes.
Recovery of plant nutrients from food residue is one of the most effective methods for resource recycling. To use food residue for hydroponics, the organic matters have to be mineralized and the nutrients have to be dissolved. Anaerobic digestion, biological oxidation, anaerobic digestion followed by biological oxidation, and wet oxidation are treatments to break down organic matter. The decomposition products of these processes are in liquid form and would be used as liquid fertilizer. The authors investigated the difference in the behaviour of nitrogen, potassium, and phosphorus in each treatment. Nitrogen was converted to ammonium by anaerobic digestion and wet oxidation, and to nitrate by biological oxidation. Potassium did not change significantly with treatment. The percentage of dissolved phosphorus in all treatments, especially in the microbial treatment, was smaller than in food residue. This is probably due to phosphorus binding to other ions and uptake by microorganisms during the treatment process.
