後藤 英司

Airflow plays a crucial role in plant growth because it supplies CO2, O2, and energy to plants in a plant factory with artificial light (PFAL). Therefore, understanding how various factors affect airflow in and around a plant canopy is essential. In this study, we developed a computational fluid dynamics (CFD) model with realistic plant structures created using structure-from-motion imaging to investigate airflow in and around a plant canopy. The averages of the absolute percentage errors of simulated air velocity in three conditions were 6.7%, 10.1%, 12.7%, respectively. The simulated and measured air velocities agreed well, confirming the accuracy of the developed CFD model. The effects of inflow velocities and plant canopy structures on the airflow in and around the plant canopy were analysed using the validated CFD model. The inflow velocities significantly decreased stagnant zones (from 62.4% to 7.2%) and increased the airflow uniformity in and around the plant canopy. A staggered layout of the plant canopy slightly decreased stagnant zones (from 16.4% to 13.2%) and increased the airflow uniformity. The airflow in and around the plant canopy was further inhibited by a large plant structure. This CFD model provided a basis for improving the airflow status in and around a plant canopy in a PFAL.

Improving edible biomass space use efficacy (EBSUE) is important for sustainably producing edamame and dwarf tomatoes in plant factories with artificial light. Photosynthetic photon flux density (PPFD) may increase EBSUE and space use efficacy (SUE). However, no study has quantitatively explained how PPFD affects EBSUE in edamame and dwarf tomatoes. This study aimed to quantitatively validate the effects of PPFD on EBSUE in dwarf tomatoes and edamame and verify whether this effect differs between these crops. The edamame and dwarf tomato cultivars ‘Enrei’ and ‘Micro-Tom’, respectively, were cultivated under treatments with PPFDs of 300, 500, and 700 µmol m−2 s−1. The results showed that the EBSUE and SUE increased with increasing PPFD in both crops. The EBSUE increased depending on the increase in SUE, the dry mass ratio of the edible part to the total plant in the edamame, and the SUE only in the dwarf tomatoes. In conclusion, a high PPFD can improve the EBSUE and SUE of edamame and dwarf tomatoes in different ways at the reproductive growth stage. The findings from this study offer valuable information on optimizing space and resource usage in plant factories with artificial light and vertical farms. Additionally, they shed light on the quantitative impact of PPFD on both EBSUE and SUE.

The effect of the ratio of red and blue light on fruit biomass radiation-use efficiency (FBRUE) in dwarf tomatoes has not been well studied. Additionally, whether white light offers a greater advantage in improving radiation-use efficiency (RUE) and FBRUE over red and blue light under LED light remains unknown. In this study, two dwarf tomato cultivars (‘Micro-Tom’ and ‘Rejina’) were cultivated in three red-blue light treatments (monochromatic red light, red/blue light ratio = 9, and red/blue light ratio = 3) and a white light treatment at the same photosynthetic photon flux density of 300 μmol m^–2 s^–1. The results evidently demonstrated that the red and blue light had an effect on FBRUE by affecting RUE rather than the fraction of dry mass partitioned into fruits (F_fruits). The monochromatic red light increased specific leaf area, reflectance, and transmittance of leaves but decreased the absorptance and photosynthetic rate, ultimately resulting in the lowest RUE, which induced the lowest FBRUE among all treatments. A higher proportion of blue light (up to 25%) led to a higher photosynthetic rate, resulting in a higher RUE and FBRUE in the three red-blue light treatments. Compared with red and blue light, white light increased RUE by 0.09–0.38 g mol⁻¹ and FBRUE by 0.14–0.25 g mol⁻¹. Moreover, white light improved the F_fruits in ‘Rejina’ and Brix of fruits in ‘Micro-Tom’ and both effects were cultivar-specific. In conclusion, white light may have greater potential than mixed red and blue light for enhancing the dwarf tomato FBRUE during their reproductive growth stage.

We previously established the selection-marker-free rice-based oral cholera vaccine (MucoRice-CTB) line 51A for human use by Agrobacterium-mediated co-transformation and conducted a double-blind, randomized, placebo-controlled phase I trial in Japan and the United States. Although MucoRice-CTB 51A was acceptably safe and well tolerated by healthy Japanese and U.S. subjects and induced CTB-specific antibodies neutralizing cholera toxin secreted by Vibrio cholerae, we were limited to a 6-g cohort in the U.S. trial because of insufficient production of MucoRice-CTB. Since MucoRice-CTB 51A did not grow in sunlight, we re-examined the previously established marker-free lines and selected MucoRice-CTB line 19A. Southern blot analysis of line 19A showed a single copy of the CTB gene. We resequenced the whole genome and detected the transgene in an intergenic region in chromosome 1. After establishing a master seed bank of MucoRice-CTB line 19A, we established a hydroponic production facility with LED lighting to reduce electricity consumption and to increase production capacity for clinical trials. Shotgun MS/MS proteomics analysis of MucoRice-CTB 19A showed low levels of α-amylase/trypsin inhibitor-like proteins (major rice allergens), which was consistent with the data for line 51A. We also demonstrated that MucoRice-CTB 19A had high oral immunogenicity and induced protective immunity against cholera toxin challenge in mice. These results indicate that MucoRice-CTB 19A is a suitable oral cholera vaccine candidate for Phase I and II clinical trials in humans, including a V. cholerae challenge study.

In a plant factory with artificial light (PFAL), upward lighting is expected to prevent senescence and decrease in the photosynthetic capacity of the lower leaves in the canopy. Upward lighting may also increase the photosynthetic rate of a canopy by improving its photosynthetic photon flux density (PPFD) distribution. However, the net photosynthetic rate (Pn) of leaves is lower when the abaxial surface is irradiated than that when the adaxial surface is irradiated. The aim of this study was to estimate the PPFD in a PFAL and the Pn of plants using three-dimensional plant models and optical simulation. First, we measured the Pn of komatsuna (Brassica rapa L. var. perviridis) leaves under different conditions of the proportion (p_ad) of PPFD on the adaxial surface to total PPFD on both surfaces and developed an equation for the light response curve of photosynthesis considering p_ad. When PPFD was low, except when it was 30 and 70 µmol m⁻² s⁻¹, Pn increased as p_ad increased, because the absorptance also increased with p_ad. Under high PPFD conditions, Pn was maximized at 67–83% of p_ad because the light would be distributed more efficiently for photosynthesis. Next, using optical simulation and the developed equation, we estimated the photosynthetic rate of a komatsuna canopy (CPn) under downward and upward lighting. The CPn increased by 1.08–1.13 times by combining downward and upward lighting due to the increase in the photosynthetic photon flux (PPF) of light incident on the canopy and the decrease in the spatial variation of PPFD on the leaves in the canopy. As the depreciation of lamps for upward lighting accounts for 7.5–9.0% of the production cost in a PFAL, even if the depreciation of lamps for upward lighting increased, enhancement of CPn by upward lighting would be cost-effective. We performed optical simulations under 220 conditions and evaluated them using CPn as an index. Moreover, we provided the proportion of PPF of upward lighting that improved CPn and discussed the reason for this improvement. The result shows that optical simulation is useful for evaluating the lighting design in a PFAL and analyzing the effects of the lighting design on the light environment and photosynthesis.

This study aimed to analyze the effects of photosynthetic photon flux density (PPFD) on fruit biomass radiation-use efficiency (FBRUE) of the dwarf tomato cultivar ‘Micro-Tom’ and to determine the suitable PPFD for enhancing the FBRUE under LED light at the reproductive growth stage. We performed four PPFD treatments under white LED light: 200, 300, 500, and 700 μmol m⁻² s⁻¹. The results demonstrated that a higher PPFD led to higher fresh and dry weights of the plants and lowered specific leaf areas. FBRUE and radiation-use efficiency (RUE) were the highest under 300 μmol m⁻² s⁻¹. FBRUE decreased by 37.7% because RUE decreased by 25% and the fraction of dry mass portioned to fruits decreased by 16.9% when PPFD increased from 300 to 700 μmol m⁻² s⁻¹. Higher PPFD (500 and 700 μmol m⁻² s⁻¹) led to lower RUE owing to lower light absorptance, photosynthetic quantum yield, and photosynthetic capacity of the leaves. High source strength and low fruit sink strength at the late reproductive growth stage led to a low fraction of dry mass portioned to fruits. In conclusion, 300 µmol m⁻² s⁻¹ PPFD is recommended for ‘Micro-Tom’ cultivation to improve the FBRUE at the reproductive growth stage.

In this study, we determined the short-term effects of ozone exposure on the growth and accumulation of bioactive compounds in red lettuce leaves grown in a controlled environment plant factory with artificial light, also known as a vertical farm. During cultivation, twenty-day-old lettuce (Lactuca sativa L. var. Redfire) seedlings were exposed to 100 and 200 ppb of ozone concentrations for 72 h. To find out how plants react to ozone and light, complex treatments were done with light and ozone concentrations (100 ppb; 16 h and 200 ppb; 24 h). Ozone treatment with 100 ppb did not show any significant difference in shoot fresh weight compared to that of the control, but the plants exposed to the 200 ppb treatment showed a significant reduction in fresh weight by 1.3 fold compared to the control. The expression of most genes in lettuce plants exposed to 100 and 200 ppb of ozone increased rapidly after 0.5 h and showed a decreasing trend after reaching a peak. Even when exposed to a uniform ozone concentration, the pattern of accumulating bioactive compounds such as total phenolics, antioxidant capacity and total flavonoids varied based on leaf age. At a concentration of 200 ppb, a greater accumulation was found in the third (older) leaf than in the fourth leaf (younger). The anthocyanin of lettuce plants subjected to 100 and 200 ppb concentrations increased continuously for 48 h. Our results suggest that ozone control is a novel method that can effectively increase the accumulation of bioactive compounds in lettuce in a plant factory.

Leafy vegetables that are offered as seedling leaves with petioles are referred to as baby leaf vegetables. One of the most nutritious baby leaves, amaranth (Amaranthus tricolor L.), contains several bioactive compounds and nutrients. Here, we investigated the growth and quality of baby leaf amaranth using a variety of short-term cooling root-zone temperatures (RZT; 5, 10, 15, and 20°C), periods (1, 3, 5, and 7 days), and combinations thereof. We observed that exposing amaranth seedlings to RZT treatments at 5 and 10°C for 1–3 days increased the antioxidant capacity and the concentrations of bioactive compounds, such as betalain, anthocyanin, phenolic, flavonoid, and ascorbic acid; however, extending the treatment period to 7 days decreased them and adversely affected growth. For RZT treatments at 20°C, leaf photosynthetic pigments, bioactive compounds, nutrients, and antioxidant capacity increased gradually as the treatment period was extended to 7 days. The integration of RZTs at 5 and 10°C for one day preceded or followed by an RZT treatment at 20°C for 2 days had varied effects on the growth and quality of amaranth leaves. After one day of RZT treatment at 5°C followed by 2 days of RZT treatment at 20°C, the highest concentrations of bioactive compounds, nutrients, and antioxidant capacity were 1.4–3.0, 1.7, and 1.7 times higher, respectively, than those of the control, and growth was not impaired. The short-term cooling RZT treatments under controlled environments were demonstrated to be adequate conditions for the improvement of target bioactive compounds in amaranth baby leaf without causing leaf abnormality or growth impairment.

Abstract Ophiorrhiza pumila is a medicinal plant that grows in subtropical forests and produces camptothecin (CPT). To determine an optimal harvest time of O. pumila in a plant factory with artificial light (PFAL), we investigated the CPT distribution in each organ and at the developmental stage and estimated the annual CPT production. For this study, the O. pumila plants were grown in controlled environments (16 h light period, photosynthetic photon flux density of 100 μmol m⁻² s⁻¹ under white light-emitting diode lamps, air temperature of 28 °C, relative humidity of 80%, and CO₂ concentration of 1000 μmol mol⁻¹). First, the stem, root, and seed pod had higher CPT contents than the leaves, flower, and ovary. The optimal harvest time of O. pumila in a PFAL was 63 days after transplanting (DAT), because the CPT content in the whole organs was the highest at the seed-ripening stage. Second, based on these results, the estimated annual CPT production of O. pumila cultivated in a PFAL was 380 mg m⁻² y⁻¹ (63 DAT). This value was 4.3 times greater than the annual CPT production by Camptotheca acuminata in a greenhouse. We concluded that the CPT production by O. pumila in a PFAL throughout the year has many advantages, although the demand for electrical energy was high compared to that of Camptotheca acuminata in a greenhouse.

The application of ultraviolet-B (UV-B) irradiation to supplement visible light as an elicitor to increase bioactive compounds under controlled conditions is increasing. This study aimed to evaluate the effects of UV-B dose and wavelength region (280–300 and 300–320 nm) on the morphological, physiological, and biochemical responses of canola plants (Brassica napus L.). Canola plants (17 days after sowing) were subjected to various UV-B intensities (i.e., 0.3, 0.6, and 0.9 W m−2) and were divided into cut and non-cut treatments for each UV treatment. Plant growth parameters exhibited different trends based on the treated UV irradiation intensity. Plant growth gradually decreased as the UV irradiation intensity and exposure time increased. Despite the same UV irradiation intensity, plant response varied significantly depending on the presence or absence of a short-wavelength cut filter (<300 nm). Canola plants suffered more leaf damage in nonfilter treatments containing shorter wavelengths (280–300 nm). UV treatment effectively activates the expression of secondary metabolite biosynthetic genes, differing depending on the UV irradiation intensity. Our results suggest that both UV irradiation intensity and wavelength should be considered when enhancing antioxidant phytochemicals without inhibiting plant growth in a plant factory with artificial light.

The demand for high-quality tomatoes is increasing; however, their production requires skillful techniques. To develop an automated irrigation method for producing high-quality tomatoes in a greenhouse, we used an image-based irrigation system to study how a diurnal periodic cycle of wilting–partial recovery irrigation affects growth, yield, and fruit quality. Three irrigation treatments were performed: a control with sufficient irrigation and two water stress treatments (moderate and severe wilting–partial recovery treatments; MPR and SPR, respectively). The mean daily maximum wilting ratios for MPR and SPR were 8.1% and 13.2% at wilting-level setpoints of 7% and 14%, respectively. The total irrigation amounts in MPR and SPR were 75% and 59% of that in the control, respectively. The corresponding yields in MPR and SPR were 76% and 56% of that in the control, respectively. The Brix and acidity of fruits in MPR and SPR were 15% and 10% and 34% and 24% higher, respectively, than those in the control at the end of the experiment. Plant growth decreased with increasing water stress levels. Plant length, leaf area, and the number of leaves were more sensitive to water stress than other growth parameters. SPR could be an effective irrigation method to improve fruit quality, even at high-air-temperature periods in summer.

Abstract UV-irradiated red perilla demonstrated promising protective effects against carbon tetrachloride-induced liver injury in mice. UV exposure significantly enhanced the accumulation of rosmarinic acid, malonylshisonin and shisonin in red perilla, and increased DPPH radical scavenging capacity. The hepatoprotective effect of UV-irradiated red perilla may be attributed to the high level of its polyphenolic compounds, which exhibit antioxidant activity.

The leaf of red perilla is used as an herbal medicine in Japan. For efficient production of red perilla in a plant factory with artificial light, it is necessary to investigate the fundamental behaviour in bioactive compounds, such as perillaldehyde (PA) and anthocyanin (ANT). Red perilla seeds were cultivated in a controlled-environmental chamber for 30 days post-germination. On day 30, the plants were grown under various levels of photosynthetic photon flux density (PPFD: 50, 100, 200, and 400 µmol m-2 s-1), provided with white fluorescent lamps in a controlled environment. After 35 days, PA and ANT levels at each different leaf position were measured. We also measured PA and ANT concentration at the same leaf position every 3 days, at 200 µmol m-2 s-1 PPFD, to investigate the changes at different leaf ages. A gradual decrease in PA concentration from the upper leaf position to the lower leaf position at all PPFD levels was observed, while the ANT concentration was almost constant regardless of leaf position. The concentration of PA was not significantly different among various PPFD levels. ANT concentration differed significantly only between 50 and 200 µmol m-2 s-1 PPFD. PA concentration gradually decreased from 3 days to 15 days after unfolding. In contrast, the ANT concentration was almost constant regardless of leaf age. Our results suggest that harvesting upper red perilla leaves is suitable for efficient production of bioactive compounds in red perilla in a plant factory.

Secondary metabolite biosynthetic pathways are influenced by environmental stressors, such as light, temperature, atmospheric gases, and air movement. To determine the dynamics of secondary metabolite biosynthesis under environmental stress in a plant factory with artificial light and to identify valuable bioactive compounds, a transcriptome analysis was performed using vegetative-stage Brassica napus L. as a model of Brassica leafy vegetables. At 18 days after sowing, plants were exposed to one of two environmental stressors for 5 days: UV-B irradiation (0.6 W m-2) and ozone (200 ppb). The growth condition was as follows: air temperature, 25/20°C (light/dark); relative humidity, 70%; light period, 16 h; photosynthetic photon flux density, 200 µmol m-2 s-1, using a white fluorescent lamp; and CO2 concentration, 1,000 ppm. The 2nd and 3rd leaves of unexposed (control) and stressor-exposed plants were sampled for both transcriptome analysis of secondary metabolite biosynthetic pathways via DNA microarrays and quantitative gene expression analysis via real-time RT-PCR, and to measure the concentration of key phytochemicals. Both the phenylpropanoid and flavonoid biosynthetic pathways were activated in the UV-treated plants, and the phenylpropanoid biosynthetic pathway was activated in the ozone-exposed plants. Consequently, the total phenolic and total flavonoid concentrations increased under these conditions. Our results show that exposure to these environmental stressors in a plant factory for a few days prior to harvest helps to effectively manipulate the accumulation of phytochemicals for intended targeted applications.

MucoRice-CTB is a promising cold-chain-free oral cholera vaccine candidate. Here, we report a double-blind, randomized, placebo-controlled, phase I study conducted in the USA in which vaccination with the 6-g dose of MucoRice-CTB induced cross-reactive antigen-specific antibodies against the B subunit of cholera toxin (CTB) and enterotoxigenic Escherichia coli heat-labile enterotoxin without inducing serious adverse events. This dosage was acceptably safe and tolerable in healthy men and women. In addition, it induced a CTB-specific IgA response in the saliva of two of the nine treated subjects; in one subject, the immunological kinetics of the salivary IgA were similar to those of the serum CTB-specific IgA. Antibodies from three of the five responders to the vaccine prevented CTB from binding its GM1 ganglioside receptor. These results are consistent with those of the phase I study in Japan, suggesting that oral MucoRice-CTB induces neutralizing antibodies against diarrheal toxins regardless of ethnicity.

The objective of this study was to investigate the growth and light-intercepting characteristics of tomatoes when movable benches are used in their cultivation. We cultivated tomatoes in a greenhouse (168 m2) during summer (9 July–9 September 2018) under different furrow distances (F1.0 = 1.0 m and F1.6 = 1.6 m) and movable benches (M indicates that the furrow distance = 0.4–0.8 m). Compared to the other treatments, when the movable bench was used to the change furrow distance depending on the plant growth stage (M treatment), the percentage of canopy light interception increased to ~90% at the early stage of plant growth (~20 days after transplanting). The percentage of canopy light interception for different treatments increased in the order of M > F1.0 > F1.6, and it increased towards the end of cultivation. In addition, the yield per unit area exhibited the same trend. Therefore, the solar radiation inside a greenhouse can be efficiently intercepted by plants when movable benches are used. This indicated that it was possible to increase plant yield per unit area using movable benches in plant cultivation.

In this study, we developed an automatic irrigation method using an image-based irrigation system for high-quality tomato production in a greenhouse by investigating effects of a diurnal periodic cycle of irrigation on the photosynthesis, growth, yield, and fruit quality of tomatoes. The diurnal periodic cycle in a moderate wilting–full recovery treatment (MR) with a medium threshold value was more frequent than that in a severe wilting–full recovery treatment (SR) with a high threshold value. Mean daily maximum wilting ratios for MR and SR were 7.2% and 11.3%, respectively, when wilting ratios were set to threshold values of 7% and 14%, respectively. Total irrigation amounts in MR and SR were similar and lower than that in the untreated control. Net photosynthetic rate decreased under water stress, with values in MR being higher than that in SR, and recovered rapidly to more than 90% of its maximum value following irrigation. Plant growth and fruit yield per plant in MR and SR were lower than that in the control. Water stress treatment could improve fruit quality when it commenced at the anthesis stage or early fruit development stage. Total irrigation amount was a more important parameter than the threshold value for controlling the growth, yield, and fruit quality of tomatoes.

Dwarf tomatoes are advantageous when cultivated in a plant factory with artificial light because they can grow well in a small volume. However, few studies have been reported on cultivation in a controlled environment for improving productivity. We performed two experiments to investigate the effects of photosynthetic photon flux density (PPFD; 300, 500, and 700 μmol m-2 s-1) with white light and light quality (white, R3B1 (red:blue = 3:1), and R9B1) with a PPFD of 300 μmol m-2 s-1 on plant growth and radiation-use efficiency (RUE) of a dwarf tomato cultivar ('Micro-Tom') at the vegetative growth stage. The results clearly demonstrated that higher PPFD leads to higher dry mass and lower specific leaf area, but it does not affect the stem length. Furthermore, high PPFD increased the photosynthetic rate (Pn) of individual leaves but decreased RUE. A higher blue light proportion inhibited dry mass production with the same intercepted light because the leaves under high blue light proportion had low Pn and photosynthetic light-use efficiency. In conclusion, 300 μmol m-2 s-1 PPFD and R9B1 are the recommended proper PPFD and light quality, respectively, for 'Micro-Tom' cultivation at the vegetative growth stage to increase the RUE.

This study aimed to evaluate short-duration (24 h) UV-B irradiation as a preharvest abiotic stressor in canola plants. Moreover, we quantified the expression levels of genes related to bioactive compounds synthesis in response to UV-B radiation. Canola seedlings were cultivated in a plant factory under artificial light (200 μmol m^–2 s^–1 photosynthetic photon flux density; white LED lamps; 16 h on/8 h off), 25°C/20°C daytime/nighttime air temperature, and 70% relative humidity. Eighteen days after sowing, the seedlings were subjected to supplemental UV-B treatment. The control plants received no UV-B irradiation. The plants were exposed to 3, 5, or 7 W m^–2 UV-B irradiation. There were no significant differences in shoot fresh weight between the UV-B-irradiated and control plants. With increasing UV-B irradiation intensity and exposure time, the H₂O₂ content gradually increased, the expression levels of genes related to photosynthesis downregulated, and phenylpropanoid and flavonoid production, and also total phenolic, flavonoid, antioxidant, and anthocyanin concentrations were significantly enhanced. The genes related to secondary metabolite biosynthesis were immediately upregulated after UV-B irradiation. The relative gene expression patterns identified using qRT-PCR corroborated the variations in gene expression that were revealed using microarray analysis. The time point at which the genes were induced varied with the gene location along the biosynthetic pathway. To the best of our knowledge, this is the first study to demonstrate a temporal difference between the accumulation of antioxidants and the induction of genes related to the synthesis of this compound in UV-B-treated canola plants. Our results demonstrated that short-term UV-B irradiation could augment antioxidant biosynthesis in canola without sacrificing crop yield or quality.

In Japan, red perilla leaves are used in the food and coloring industries, as well as in crude medicine. Perilla leaves contain a high concentration of phytochemicals such as perillaldehyde (PA) and rosmarinic acid (RA). The effects of UV-B radiation intensity (0.05-0.2 W m(-2), UV-B-BE: 0.041-0.083 W m(-2)), duration (3 or 6 h), and irradiation method (continuous or intermittent) for artificial nocturnal lighting using UV-B fluorescent lamps were evaluated on growth, flowering, and leaf phytochemical concentration in greenhouse-grown perilla. Under continuous UV-B irradiation at 0.1 W m(-2) for 3 or 6 h, leaf color changed from red to green and leaf fresh weight decreased, compared with the control treatment. No leaf color change was observed under the 3-h treatment with UV-B radiation at 0.05 W m(-2), wherein leaf fresh weight was similar to that of the control. Furthermore, RA concentration under continuous UV-B irradiation at 0.05 W m(-2) for 3 h increased two-fold compared to that under control treatment, while PA concentration was not affected by UV-B irradiation. Thus, our data showed that continuous UV-B irradiation at 0.05 W m(-2) for 3 h could effectively produce RA-rich perilla leaves without reducing in phenotypic quality or productivity. However, a 6-h intermittent illumination inhibited flowering without altering phytochemical concentration.

Plant genomes remain highly fragmented and are often characterized by hundreds to thousands of assembly gaps. Here, we report chromosome-level reference and phased genome assembly of Ophiorrhiza pumila, a camptothecin-producing medicinal plant, through an ordered multi-scaffolding and experimental validation approach. With 21 assembly gaps and a contig N50 of 18.49 Mb, Ophiorrhiza genome is one of the most complete plant genomes assembled to date. We also report 273 nitrogen-containing metabolites, including diverse monoterpene indole alkaloids (MIAs). A comparative genomics approach identifies strictosidine biogenesis as the origin of MIA evolution. The emergence of strictosidine biosynthesis-catalyzing enzymes precede downstream enzymes' evolution post γ whole-genome triplication, which occurred approximately 110 Mya in O. pumila, and before the whole-genome duplication in Camptotheca acuminata identified here. Combining comparative genome analysis, multi-omics analysis, and metabolic gene-cluster analysis, we propose a working model for MIA evolution, and a pangenome for MIA biosynthesis, which will help in establishing a sustainable supply of camptothecin.

<p>Sweet basil (Ocimum basilicum L.), one of the most widely consumed herbs globally, is used in raw or processed food, and for aromatic essential oils. We investigated the effects of photosynthetic photon flux density (PPFD; 150, 225, and 300 μmol·m⁻²·s⁻¹, herein, referred to as P150, P225, and P300) and red to blue light ratios (R/B ratio) (R:B = 1:4, 1:1, and 4:1, herein, referred to as R/B 0.25, 1.0, and 4.0) with a 16 h light period on the leaf shape and concentrations of functional and aromatic compounds in basil. Total leaf dry weight and leaf mass per area increased with increasing PPFD and R/B ratio. Total leaf area tended to increase with increasing R/B ratio at the same PPFD. Although the highest growth was noted when R/B was 4.0 at P300, the leaves showed ruggedness and curling. β-Carotene concentration based on the leaf dry weight and leaf area at the fourth node increased with decreasing R/B ratio, regardless of PPFD. Concentrations of aromatic compounds (eugenol and linalool) based on dry weight were significantly higher at P150 than at other PPFDs and in treatments with greater amounts of red light. These results suggest that basil growth, appearance, and functional and aromatic compound concentrations can be adjusted as needed by manipulating the PPFD and R/B ratio, although R/B 4.0 at P300 caused malformed leaves.</p>

BackgroundWe have previously developed a rice-based oral vaccine against cholera diarrhea, MucoRice-CTB. Using Agrobacterium-mediated co-transformation, we produced the selection marker-free MucoRice-CTB line 51A, which has three copies of the cholera toxin B subunit (CTB) gene and two copies of an RNAi cassette inserted into the rice genome. We determined the sequence and location of the transgenes on rice chromosomes 3 and 12. The expression of alpha-amylase/trypsin inhibitor, a major allergen protein in rice, is lower in this line than in wild-type rice. Line 51A was self-pollinated for five generations to fix the transgenes, and the seeds of the sixth generation produced by T5 plants were defined as the master seed bank (MSB). T6 plants were grown from part of the MSB seeds and were self-pollinated to produce T7 seeds (next seed bank; NSB). NSB was examined and its whole genome and proteome were compared with those of MSB.ResultsWe re-sequenced the transgenes of NSB and MSB and confirmed the positions of the three CTB genes inserted into chromosomes 3 and 12. The DNA sequences of the transgenes were identical between NSB and MSB. Using whole-genome sequencing, we compared the genome sequences of three NSB with three MSB samples, and evaluated the effects of SNPs and genomic structural variants by clustering. No functionally important mutations (SNPs, translocations, deletions, or inversions of genic regions on chromosomes) between NSB and MSB samples were detected. Analysis of salt-soluble proteins from NSB and MSB samples by shot-gun MS/MS detected no considerable differences in protein abundance. No difference in the expression pattern of storage proteins and CTB in mature seeds of NSB and MSB was detected by immuno-fluorescence microscopy.ConclusionsAll analyses revealed no considerable differences between NSB and MSB samples. Therefore, NSB can be used to replace MSB in the near future.

Phytochemicals derived from secondary metabolites that are accumulated in plant leaves are used as functional foods, pharmaceutical materials, and raw materials for industry. Secondary metabolite biosynthesis pathways are influenced by environmental stresses including light, temperature, atmospheric gases, and nutrient solution. In this study, we determined the environment conditions that would increase or decrease the content of phytochemical compounds under totally controlled environments such as plant factories. We used vegetative-stage Brassica napus L. and Nicotiana benthamiana as model plants for Brassica leaf vegetables and for the production of pharmaceutical and industrial raw materials, respectively. At 18-25 days after sowing, plants were exposed to four environmental stress factors, alone or in combination for 3-6 days: UV-B irradiation (0-1.0 W m , low nutrient solution temperature (5-15°C), and ozone gas exposure (100-400 ppb). For plants either exposed and not exposed (control) to stress, the third and fourth leaves were sampled for transcriptome analysis of secondary metabolite pathways using DNA microarrays, quantitative gene expression analysis using real-time RT-PCR, and measurement of the concentration of key phytochemicals using HPLC. Ascorbic acid, isoprenoid, and flavonoid pathways were activated in N. benthamiana upon exposure to UV irradiation or a combination of UV and low solution temperature. Low solution temperature increased expression of some alkaloid pathway genes. In B. napus, the phenylpropanoid and flavonoid pathways were activated following exposure to UV irradiation or ozone gas. Consequently, antioxidant capacity and total phenolic content increased under these conditions. However, the carotenoid pathway was not activated in either of the plant species following UV or ozone exposure. Thus, exposure to these environment stresses can be used to manipulate phytochemical compound accumulation targeted to the intended use. -2)

For the production of high-quality tomato fruit (i.e., fruit with high sugar content), it is necessary to apply water absorption stress through irrigation restriction. However, excessive deficit irrigation (DI) often leads to severe growth inhibition and irreversible wilting; therefore, stable production of high-quality tomato requires frequent observation and irrigation control by growers, making the process labor intensive. In the present study, we aimed to develop an automatic system of water-stress control by image analysis. First, we subjected tomato plants to DI treatment manually in a summer greenhouse and automatically captured tomato canopy images using an overhead camera every 1 min. Using an original software, we determined the projected leaf area (PLA) from the canopy images under various natural light conditions and calculated the wilting ratio (W; percentage of PLA per non-wilting PLA in the early morning). During this period, we randomly measured the leaf water potential (LWP) destructively at various wilting stages. The results revealed a significant negative correlation between the W (0-25%) and LWP (-0.2 to -1.5 MPa). According to the manual irrigation timing, the appropriate range of the setting value of W and LWP for irrigation was 15 to 20% and -1.02 to -1.21 MPa, respectively. Next, we installed this software into an irrigation system and controlled the W under DI treatment, as a measure of water-stress level of tomato canopy, automatically for a few months. The Brix percentage of tomato under DI was higher (8.0%) than that of tomato under sufficient irrigation (control) (5.5%) and the total yield under DI was 40% that of the control. Overall, appropriate LWP for other canopies or in other greenhouses can be adjusted using the W calculated from photo-images. In conclusion, we developed a control system of plant water-stress level by photo-image analysis for stable high-quality tomato production.

Good lighting designs can establish suitable light environments in plant factories with artificial light (PFALs). This study used optical simulations to investigate the effects of lighting designs in PFALs on the coefficient of variation of light absorption (Φp; CV) of individual plants and the coefficient of utilization for the lighting system (U). Three‐dimensional models of canola plants were constructed using a scanner, and a 3D model of the cultivation shelf was also created. The photosynthetic photon flux density (PPFD) distribution in the cultivation spaces, with or without the canola plants, was estimated first. The PPFD on the canola leaves was then estimated when the lighting design parameters, such as number, distance, height, radiant flux, and light distribution of the light‐emitting diode lamps, were modified. The optical simulation showed good accuracy when estimating the PPFD distributions on the cultivation shelf and the leaves of the canola plants. The results showed that while the PPFD distribution across the growing area was uniform, it was not on a plant canopy. By appropriately controlling the layout of the lamps and their directionality, lighting designs that reduce Φp; CV and improve U in PFAL could be possible, and optical simulations could help to develop them.

Monitoring the growth of fruit vegetables is essential for the automation of cultivation management, and harvest. The objective of this study is to demonstrate that the current sensor technology can monitor the growth and yield of fruit vegetables such as tomato, cucumber, and paprika. We estimated leaf area, leaf area index (LAI), and plant height using coordinates of polygon vertices from plant and canopy surface models constructed using a three-dimensional (3D) scanner. A significant correlation was observed between the measured and estimated leaf area, LAI, and plant height (R > 0.8, except for tomato LAI). The canopy structure of each fruit vegetable was predicted by integrating the estimated leaf area at each height of the canopy surface models. A linear relationship was observed between the measured total leaf area and the total dry weight of each fruit vegetable; thus, the dry weight of the plant can be predicted using the estimated leaf area. The fruit weights of tomato and paprika were estimated using the fruit solid model constructed by the fruit point cloud data extracted using the RGB value. A significant correlation was observed between the measured and estimated fruit weights (tomato: R = 0.739, paprika: R = 0.888). Therefore, it was possible to estimate the growth parameters (leaf area, plant height, canopy structure, and yield) of different fruit vegetables non-destructively using a 3D scanner. 2 2 2

The medicinal plant, Ophiorrhiza pumila, naturally grows on the floors of humid inland forests in subtropical areas. It accumulates camptothecin (CPT), which is used as an anti-tumor agent, in all organs. We investigated the optimal hydroponic root-zone environments for growth and CPT accumulation in O. pumila in a plant factory. In experiment 1, to determine the appropriate nutrient solution concentration (NSC), O. pumila was cultivated using four concentrations (0.125, 0.25, 0.5, and 1.0 times) of a commercial solution for 63 days after the start of treatment (DAT). The electrical conductivity of these NSCs was 0.6, 0.9, 1.5, and 2.7 dS m , respectively. The total dry weights at 0.25 and 0.5 NSCs were higher than those at the other two NSCs. CPT content at 0.25 NSC was significantly higher than those at other NSCs. In experiment 2, to investigate an appropriate nutrient solution temperature (NST), O. pumila was cultivated at four NSTs (10, 20, 26, and 35 °C, named as T10, T20, T26, and T36, respectively) for 35 DAT. The growth and CPT content at T20 was the highest among the treatments. Therefore, root-zone environments of 0.25 NSC and 20 °C of NST produced the best growth and CPT accumulation in O. pumila. −1

We determined the effects of UV radiation and low root zone temperature on growth characteristics and phytochemicals of Brassica napus (canola) cultivated in a controlled environment (25/20 °C 16/8 [light/dark]; 70% relative humidity; 1000 µmol mol CO with photosynthetic photon flux density of 100 and 200 µmol m  s for 7 and 18 days, respectively). The 18-day-old B. napus plants were treated for 5 days with two nutrient solution–temperature regimes (normal temperature [NT] and low-temperature [10 °C; LT]) and three levels of UV radiation (0, 0.3, and 0.6 W m ). Treatment with 0.6 W m UV decreased quantum efficiency of photosystem II the most. Most growth characteristics decreased under LT + UV treatments. Treatments with 0.6 W m UV, compared to those without UV, significantly inhibited shoot height. LT + 0.3 and +0.6 UV decreased shoot height the most. Temperature (T) × UV interaction did not affect most growth characteristics except leaf area, specific leaf weight, and shoot water content. Antioxidant capacity (total ORAC) resembled lipophilic ORAC and showed the highest value in the LT + 0.6 UV treatment. T × UV interaction did not affect ORAC values, although LT + 0.3 UV and LT + 0.6 UV treatments produced the highest values. Both LT and UV radiation enhanced the total phenolic content, and in the combined treatments, it was two times that of the control. UV intensities (0.3 and 0.6 W m ) remained constant regardless of variation in root zone temperature. UV radiation enhanced total flavonoid content equally across different intensities; LT + 0.6 W m UV treatment produced a relatively high value. Thus, LT and UV negatively affected plant growth parameters, except total dry weight, whereas LT, UV, or LT + UV positively affected antioxidant properties, total phenolics, and flavonoids, suggesting the potential of using an LT treatment in a hydroponic system as well as UV radiation to enhance growth performance of greenhouse and factory plants. −1 −2 −1 −2 −2 −2 −2 −2 2

In a plant factory with artificial light, accumulation of bioactive compounds can be enhanced via precise environmental control. Light is essential for growth and development, and for the production of bioactive compounds in plants. Ultraviolet (UV) light stimulates bioactive compound biosynthesis in plants including antioxidants. We developed a new and economical UV-rich fluorescent lamp (UV-FL), with the ability to adjust the ratio of UV-A and UV-B. The objective of this study was to determine the effect of UV light on the accumulation of bioactive compounds in red leaf lettuce. Red leaf lettuce plants were grown in a plant factory with normal growing conditions under white light as light source (23/20°C, 70% RH, 16 h light period, PPFD 150 μmol m s , 1,000 ppm CO2) for 23 days. The plants were subjected to UV light under white light (low, middle, and high; 0.3, 0.6, and 0.9 W m ) for 3 days before harvest. Fresh and dry weights of shoot, leaf area, total chlorophyll, total phenolic concentration, and ORAC for antioxidant activity were measured before and after the UV treatments. Middle and high UV treatments resulted in negative effects on the growth characteristics such as shoot fresh and dry weight, and leaf area. However, low UV treatment was not significantly different from the control for shoot dry weight. Total chlorophyll was higher in low and middle UV treatments than the high UV treatment and the control. In contrast, total phenolic concentration and ORAC value of lettuce plants grown under UV treatments were significantly higher than that of the control. This study suggests that short-term UV irradiation using economical UV-FL lamp before harvest was effective in improving the vegetable quality. -2 -1 -2

Red perilla (Perilla frutescens) is used as food, crude drug, and cosmetics. The major bioactive compounds of red perilla are perillaldehyde, rosmarinic acid, luteolin, and anthocyanin. In this study, we evaluated the effects of UV light on the accumulation of the bioactive compounds and gene expression of related enzymes under controlled environments. Red perilla was cultivated in a controlled-environment room for 35-42 days after germination. The growing condition was air temperature 25/20°C (light/dark), R.H. 70%, light period 16 h, 200 µmol m s of PPFD and CO2 conc. 1000 ppm. The plants were exposed to UV-B light of 1.0 W m for 3 days. The concentrations of perillaldehyde (PA), rosmarinic acid (RA), and anthocyanin (ANT) were measured by HPLC. The expression levels of genes related to RA and ANT synthesis were analyzed by RT-RT-PCR. The PA and RA concentrations at 3 days after the start of UV irradiation increased compared to that of the control. The expression of phenylalanine ammonia-lyase (PAL) and thyrosin aminotransferase (TAT), key genes of the phenylpropanoid pathway for RA synthesis, was higher at 48-72 h in the UV treated plants than those in the control after the start of UV irradiation. The RA concentration increased as a result of antioxidant response to the ROS generated by exposure to UV light. The expression of five genes in the flavonoid pathway increased 24 h after the start of UV irradiation. Total ORAC values of the plants under UV treatment was higher than in the control. Based on the results, we conclude that a short period of UV-B irradiation stimulates the phenylpropanoid pathway for the biosynthesis of RA, and drives the flavonoid pathway for production of ANT, in addition to enhancing the production of other antioxidant compounds. -2 -1 -2

We investigated the combined influence of cooling using electric heat pumps and CO enrichment in a closed greenhouse equipped with a near infrared solar radiation (NIR)-reflecting film on the yield and quality of tomato fruits during the summer season. The air temperature of the ‘Control' greenhouse were controlled through conventional natural ventilation windows, shading curtains and a fog cooling system. The air temperature of the ‘Closed' greenhouse were controlled by cooling of electric heat pumps and a NIR-reflecting film curtain. The CO concentration was maintained at around 1000 µmol mol in the Closed greenhouse. During the experiment period when the outside temperature of the greenhouses was relatively high, the mean daytime air temperature was cooler by more than 3 °C in the Closed greenhouse than that in the Control. The total dry weight of the tomato plants and fruit yield per plant at the end of the experiment was significantly higher in the Closed greenhouse compared to the Control. The result indicated that the improved yield and quality of the Closed greenhouse resulted from the air temperature being controlled within the optimal range for growth and the subsequent increased rates of fruit maturation and photosynthesis due to CO enrichment. 2 2 2 -1

Ophiorrhiza pumila is a medicinal plant distributed on the floors of humid inland forests in subtropical areas and accumulates camptothecin (CPT) in whole plant organs. To elucidate the proper light and air temperature conditions for plant growth and CPT yield, we conducted two experiments under controlled environments. In experiment 1, we measured the net photosynthetic rate (P ) and transpiration rate (E) of the whole plant O. pumila using an open-type assimilation chamber under different photosynthetic photon flux densities (PPFDs) and air temperatures. The result showed that the combination of an air temperature of 28 °C and a PPFD of 100 μmol m s was a good condition for photosynthesis and transpiration. In experiment 2, O. pumila was cultivated for 35 days under three PPFDs and three light periods at an air temperature of 28 °C. At a PPFD of 100 μmol m s and a light period of 16 h, growth was accelerated by the generating the lateral shoots and branches, and total CPT content per plant was the highest among these treatments. The present study revealed that the proper PPFD and light period conditions could enhance growth and CPT accumulation of O. pumila. n -2 -1 -2 -1

We constructed 3D models of the greenhouse (168 m ) and tomato plants (plant height: 150 cm). The point cloud data of tomato plants was acquired by a 3D scanner and converted to the 3D model, which was constructed using polygons. The canopy 3D model was installed in the greenhouse 3D model. In addition, the date, time, latitude, longitude, global solar radiation, and optical properties of objects, such as plants and covering material, were used as input values to estimate the amount of solar radiation received by canopy models using the ray tracing. The amount of solar radiation received by the canopy models at different layers under different furrow distances (60-160 cm) was calculated every 1 h. The lower layer and the middle layer of tomato plants were saturated with solar radiation at furrow distances of 120 cm and 100 cm, respectively. However, the radiation received by the upper layer of tomato plants did not change across the range (60-160 cm) of investigated furrow distances. This investigation has provided a visual demonstration of the relationship between the arrangement of cultivated fruit and vegetable plants, such as tomato, in the greenhouse and the amount of solar radiation received. 2

A closed plant production system with artificial lighting (CPPS) is ideal for the propagation of pharmaceutical products using genetically modified (GM) plants. The pharmaceutical products that have been or are being developed include oral vaccines for humans or livestock and agents that prevent lifestyle-related diseases. We developed a CPPS for stable accumulation of high concentrations of desired functional proteins in the edible components of strawberry, tomato, and rice plants. Because responses of GM plants to environmental conditions have not been investigated, we researched the physiological characteristics of plants under artificial conditions; this included the effects of light quality, light intensity, light period, carbon dioxide concentration, composition and concentration of nutrient solution, and planting density. We determined the appropriate environmental conditions for optimizing strawberry, tomato, and rice plant production of valuable materials in large quantities.

Transgenic ever-bearing strawberry (Fragaria×ananassa Duch. ‘HS 138’) was cultivated in a closed plant production system to produce functional proteins that can enhance human immune functions. We investigated the effects of air temperature before harvest on fruit growth and the concentration of human adiponectin (hAdi) at harvest in transgenic strawberry. During the different stages of maturity (mature white and immature green stages), hAdi-expressing plants were exposed to four air temperature treatments (15, 20, 25, and 30°C) under 24-h illumination provided by fluorescent lamps. Fruits were harvested at the mature red stage. The number of days to the mature red stage decreased with increasing air temperature, being the least at 30°C. Fruit total soluble protein (TSP) concentration increased with decreasing air temperature, particularly at 15°C, whereas fruit hAdi concentration tended to be higher under the 30°C treatment than under any other of the temperature treatments. There was no significant relationship between fruit fresh weight at harvest time and hAdi concentration within treatments, nor between the number of days to harvest and hAdi or TSP concentration. Although there were no significant differences in fruit hAdi content among treatments, hAdi production rate was the highest at 30°C because of the shortest duration to harvest. These results indicate that a higher air temperature promoted fruit maturation and accelerated the production of functional hAdi proteins in the fruit. For hAdi-expressing strawberry plants, exposure to 30°C may reduce energy consumption (lighting and air conditioning) for functional protein production under controlled environments.

Light quality is an important environmental factor that regulates stem length of the tomato (Solanum lycopersicum). Previously, we showed that the stem length of tomato seedlings grown under red (R) light emitting diodes (LEDs) was significantly longer than that of seedlings grown under blue (B) LEDs or a mixture of B and R LEDs; further, the light intensity of B LED negatively correlated with the stem length. This study aimed to elucidate the mechanism of how B and R lights affect stem elongation. We analyzed the levels of gibberellins (GAs) and the expression of genes associated with their metabolism in tomato seedlings grown under different B and R light conditions. The level of bioactive GA, GA , was significantly higher in the seedlings grown under R LED than in those grown under other light conditions. In addition, an increase in the B to R light ratio increased the transcript level of the GA inactivation enzyme gene, SlGA2ox7. Moreover, the transcript level of SlGA2ox7 increased with the intensity of B light, and was negatively correlated with the stem length of the seedlings. These results indicated that the B light intensity controlled GA inactivation of the seedlings, and endogenous GA contents may affect stem elongation. Further, we found that the transcript level of the GA biosynthesis enzyme gene, SlGA3ox3, in the seedlings grown under R LED was significantly higher than that under other light conditions. This could be due to depletion of B light and suggests that GA biosynthesis may be involved in the stem elongation of seedlings grown under low B light conditions. 4

Plant factories with artificial lighting have been developed to improve food production, functional ingredients, and profitability. Intensive research has been performed to elucidate the effects of light intensity and wavelength on plant growth and nutritional quality with the use of light-emitting diodes (LEDs). In particular, the effects of monochromatic red, blue, or simultaneous red + blue light have been studied because these wavelengths are predominantly used for photosynthesis. We examined the effects of alternating red and blue light provided by LEDs over a period of 24 hours on the growth and nutritional properties of leafy lettuce. The results clearly show that alternating red and blue light accelerated plant growth significantly compared with white fluorescent lamps or red and blue LEDs at the same daily light integral. Plants grown under alternating red/blue light had a greater net assimilation rate and total and projected leaf area (an indicator of the fraction of leaf area that absorbs more light) than other plants. Additionally, alternating red and blue light maintained high concentrations of sugars, ascorbic acid, and anthocyanins in leaves. Taken together, the results indicate that continuous irradiation with alternating red and blue light could enhance growth while maintaining the nutritional quality in lettuce.

Tomato (Solanum lycopersicum) is a model crop for studying development regulation and ripening in flesh fruits and vegetables. Supplementary light to maintain the optimal light environment can lead to the stable growth of tomatoes in greenhouses and areas without sufficient daily light integral. Technological advances in genome-wide molecular phenotyping have dramatically enhanced our understanding of metabolic shifts in the plant metabolism across tomato fruit development. However, comprehensive metabolic and transcriptional behaviors along the developmental process under supplementary light provided by light-emitting diodes (LEDs) remain to be fully elucidated. We present integrative omic approaches to identify the impact on the metabolism of a single tomato plant leaf exposed to monochromatic red LEDs of different intensities during the fruit development stage. Our special light delivery system, the “simplified source-sink model,” involves the exposure of a single leaf below the second truss to red LED light of different intensities. We evaluated fruit-size- and fruit-shape variations elicited by different light intensities. Our findings suggest that more than high-light treatment (500 μmol m s ) with the red LED light is required to accelerate fruit growth for 2 weeks after anthesis. To investigate transcriptomic and metabolomic changes in leaf- and fruit samples we used microarray-, RNA sequencing-, and gas chromatography-mass spectrometry techniques. We found that metabolic shifts in the carbohydrate metabolism and in several key pathways contributed to fruit development, including ripening and cell-wall modification. Our findings suggest that the proposed workflow aids in the identification of key metabolites in the central metabolism that respond to monochromatic red-LED treatment and contribute to increase the fruit size of tomato plants. This study expands our understanding of systems-level responses mediated by low-, appropriate-, and high levels of red light irradiation in the fruit growth of tomato plants. -2 -1

薬用アカジソの最大展開までの個葉の成長に伴う生理活性物質濃度の経日変化ならびに，その期間における10 ℃での低培養液温処理の影響を調査した．10 ℃での低培養液温処理で少なくとも6日までは地上部の生育は抑制されないことが示された．個葉の主要な生理活性物質の濃度は，展開開始後経日的に変動し，成分の種類によってその挙動は異なった．また，低培養液温処理により主な生理活性物質の濃度はControlより高くなり，その時期は生理活性物質により異なった．

Most strawberry fruits in Japan are produced under forced-production culture, using June-bearing cultivars. Strawberry plants are transplanted in a heated greenhouse in autumn and the normal harvest period is from late November to June. Insufficient solar radiation for fruit loading during the winter sometimes causes a decline in growth and yield. Therefore, we investigated the effects of supplementing natural light with artificial lights using light-emitting diodes (LEDs). The experiment was conducted in a greenhouse (2400 m in area) located in Yamamoto town, Miyagi prefecture, Japan (37.961°N, 140.877°E). Strawberry plants were transplanted in an elevated bed. We ran two experiments: experiment 1 was on light quality [photosynthetic photon flux density (PPFD) ratio of red light to blue light], while experiment 2 examined various lamp positions relative to the plants. In experiment 1, strawberry plants were exposed to three different qualities of light (red-to-blue ratios of 2:1, 3:1, and 4:1) with LED lamps (peak blue wavelength 450 nm, peak red wavelength 660 nm, SFL 120 BR-ERx). In experiment 2, LED lamps of two light qualities (red-to-blue ratios of 3:1 and 4:1) were installed in three different positions (above, in the middle, and at the bottom of treatment containers). Yields increased in almost all supplementary-light treatments relative to controls in both experiments. In experiment 1, the yield was higher when the PPFD ratio was 3:1 or 4:1 than when it was when 2:1. In experiment 2, strawberry yield increased by about 10% relative to the control, but no significant difference was observed among light positions or light quality. In addition, no increase in total dry weight was observed as a result of supplemental lighting, but the fruit distribution ratio (fruit dry matter/total dry matter) increased. It is possible that morphological changes caused by supplemental LED lighting led to the increase in fruit yield. 2

Red perilla (Perilla frutescens) is used as food, stomachic and antitussive crude drugs, and anti-allergy supplements. The major bioactive compounds of red perilla are perillaldehyde (PA), rosmarinic acid (RA), luteolin (LU), and anthocyanin (ANT). In this study, we investigated the effects of 6 days low (10, 12, and 15°C) and control (20°C) nutrient solution temperature (NST) treatments on plant growth and major bioactive compound concentrations in red perilla leaves at the node position. No significant difference was detected in the dry weight of leaves of the main shoot, which is the main part harvested, among the treatments. However, leaf water content (%) tended to decrease with a decrease in NST, especially in plants grown at 10°C NST, which exhibited values significantly lower than those of plants grown at 15°C and 20°C NSTs. PA and ANT concentrations in the 3rd to 5th nodes did not differ among treatments. Conversely, RA concentration increased with a decrease in NST, irrespective of the node position. LU concentration at 10°C NST was the highest in all treatments, irrespective of the node position. This suggested that the production of bioactive compounds under the low NSTs differed depending on leaf maturity stage and compound. Additionally, the contents of RA and LU in the whole plant increased because there was no reduction in growth of the harvested part under the low NSTs. Therefore, 6 days exposure to root-zone temperatures at 10°C appears to be an effective method to increase both RA and LU concentrations and their contents in the whole plant of red perilla for its use as a crude drug or medicinal material.