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One of the main components of the successful production of plant products is the choice of crops with a high realization of their production potential under the formed conditions, including in the conditions of intensive light culture. The problem of compensating or eliminating the deficit of green crops is currently quite acute in Russia and in the world. The genetic diversity of the most widespread green brassicas plants of the species Brassica rapa L. for use in protected ground facilities has developed in Southeast Asia and includes numerous morphotypes of Chinese cabbage, pakchoi, tatsoi, wutacai, mizuna, and leafy turnip. In Russia, leafy B. rapa vegetables are used to a limited extent, mainly as salad vegetables. The main areas of B. rapa crops breeding for artificial light culture include a high growth rate (the duration of vegetative period is not more than 28-35 days, depending on the biological characteristics of the crop), the yield is not less than 3-8 kg/m2, depending on crops, a certain compact plant habit, high quality of leaves, valuable biochemical composition, resistance to early bolting, resistance to possible low light and high air temperature, suitability for growing in a thin layer of soil or hydroponics. The biological features of the diversity of B. rapa leafy crops as sources for breeding for intensive light culture conditions have not been sufficiently studied, first of all, this concerns little-known crops (tatsoi, wutacai, mizuna) and certain morphotypes within common crops (Chinese cabbage and pakchoi). In this study, for the first time, we studied the wide genetic diversity from the Russian worldwide B. rapa collection of the Russian Federation, stored in the VIR, and morphotypes within them (72 accessions), including genotypes contrasting in morphological characteristics, under different supply light intensity for the development of energy-saving agro-technologies in intensive light culture. For the first time, correction factors were determined for calculating the leaf surface area from easily measured linear dimensions for each studied crop and type of leaves, which will speed up the calculations of photosynthesis characteristics. A different degree of variation in the variability of the size and weight of plants of various crops, depending on the illumination, is shown, the highest in Chinese cabbage and leafy turnip. It was found that the intensity of the light regime is largely determined the increase in the productivity of plants of all studied crops, mostly of Chinese cabbage and pakchoi and leafy turnip. High-yielding accessions of Chinese cabbage, pakchoi and leafy turnip were identified (more than 6.3 kg/m2 for 28 days of growing season). The studied accessions of wutacai and mizuna are low-yielding and have a longer growing season, but are of interest as vegetables for functional nutrition and for decorative purposes. Semi-cabbage types of Chinese cabbage (Shantung, Santo, Xiao), which are of primary interest for light culture, have been identified. We recommend Chinese cabbage accessions vr.k-1375, Bice (vr.k-1376), and pakchoi k-647 for thickened cultivation,, and pakchoi Extra Dwarf Pack Choi (vr.k-1405 ) and tatsoi Xiao Ba Je Ta Cai (k-695) for growing with a small distance between the shelves of 25 cm. Accessions of Chinese cabbage Chokurei (k-177), Tokyo Bekana (k-395), Zao Shi No. 5 (vr.k-1120), and Fun jen F1 (vr.k-1410) showed the highest salad qualities of the leaves. Under the conditions of a biopolygon, we managed to determine accessions with a stable manifestation of the traits, of early maturity and high productivity, practically independent of light intensity. These are accessions of Chinese cabbage Harumaki Shin Santousai (k-270), Tokyo Bekana (k-395), Xiaobaikou (k-74), pakchoi Kangre 605 (vr.k-1131), Gai Lang Jin Pin 25 F1 (vr.k-1124). In addition, it was shown that the Chinese accession of Chinese cabbage Zao Shi No. 5 (vr.k-1120) and the Russian cultivar of the leafy turnip Selecta (vr.k-1371) have increased the activity of the photosynthetic apparatus. The obtained data on the crops in general and the determined accessions of B. rapa are of interest for the practice of vegetable growing, in the development of elements of cultivar technology of B. rapa crops under conditions of light culture and as sources of valuable traits in breeding programs, including the development of city farming.

In this study, the nutritional value of Brassica leafy greens in different growth stages was investigated. Mustard (Brassica juncea L., 'Red Lion') and tatsoi (Brassica rapa var. rosularis) were grown indoors under light-emitting diodes (blue 447 nm, red 638 nm, red 665 nm, far-red 731 nm LEDs) lighting (total PFD 300±10 µmol m(‑2) s(‑1); 16 h day(‑1)). The contents of saccharides, phytochemicals, nitrates and mineral elements at microgreen (7 days), baby-leaf (21 days) and technical maturity (mustard - 31 days, tatsoi - 40 days) growth stages of leafy greens were evaluated. The significantly higher content of glucose (about 50%) and fructose (44% more) in baby leaf mustard and tatsoi were determined, in comparison to microgreens and technical maturity plants. Also, about 43% more phenolic compounds and 49% higher DPPH free radical scavenging activity in both species baby-leaf plants were determined. The mustard microgreens accumulated the significantly higher contents of NO(3-) (about 79%) and NO(2-) (about 68% more), and about 28% less Fe and 42% lower content of macro elements. A similar tendency on mineral elements in tatsoi was determined; however, approximately 70% higher contents of NO(3-) and 87% of NO(2-) in technical maturity tatsoi were determined. In conclusion, the contents of antioxidant properties having metabolites, NO(3-), NO(2-) and mineral elements in Brassica leafy greens varied depending on age, and the baby-leaf plants showed higher nutritional value, in comparison to microgreens or mature plants.

Demand for Asian vegetables is rising rapidly due to changing demographics and increasing consumer awareness of their health benefits. However, growers are not familiar with growing these “foreign” crops due to insufficient technical information regarding suitable cultivars for different regions, production schedules, disease and pest susceptibility, and postharvest management. The objective of this study was to conduct trials in different production systems and climate regions to demonstrate the potential of growing Asian vegetables in Texas. We conducted preliminary trials of nine leafy greens in the open field, high tunnel, and greenhouse (container and hydroponic production) to explore the suitability and potential for year-round production. We also conducted field trials for warm season crops in the open field in different climate zones. Results indicated that for cool season leafy greens, open field production has a limited growing season, high tunnel has the potential to extend the growing season, while greenhouse may provide year-round production using soilless substrate container culture or hydroponic system. For warm season crops, early planting is recommended for high yield. Additional research is warranted in different regions to test more species and cultivars and optimize the production system of high-performing cultivars to maximize production and profitability.

Green leafy vegetables occupy a very important place in the human diet, however, they also represent a group of plants that tend to accumulate nitrates in their tissues. In recent years, nitrate problems have been revived in closed environment intense cultivation systems. In such systems, it is possible to control nitrate metabolism by tailoring controllable environmental parameters. In this study we review the effects of light-emitting diode (LED) lighting spectrum and photosynthetic photon flux density (PPFD) on nitrate assimilation in green vegetables. Experiments were performed in closed environment growth chambers (21/17°C day/night temperature, ~65% relative humidity). Green and red leaf lettuces (Lactuca sativa ‘Lobjoits green cos’ and ‘Red cos’) and tatsoi (Brassica rapa var. rosularis ‘Rosetto’ F(1)) were cultivated under combinations of red (660, 640 nm), blue (445 nm) and far-red (731 nm) LED lighting under a PPFD of 100-300 µmol m(‑2) s(‑1). The activities of nitrate, nitrite, nitrate reductase and nitrite reductase, as well as total protein content were evaluated. Both spectral differences and light intensity have remarkable, species-specific effects on nitrate contents and activities of reducing enzymes.

Iturin A and surfactin are antimicrobial cyclic lipopeptides secreted by antagonistic Bacillus strains, and both elicit defence gene expression in host plants. We previously showed that a soil amendment with either of the purified lipopeptides confers suppression against Fusarium yellows of tatsoi (Brassica rapa) caused by the soil-borne pathogen Fusarium oxysporum and that excess amounts of iturin A or surfactin do not confer suppression. Here, we evaluated the impacts of purified iturin A or surfactin against Fusarium wilt of lettuce (Lactuca sativa). As a soil amendment, iturin A and surfactin each conferred suppression of Fusarium wilt of lettuce on diverse lettuce cultivars similar to the results for tatsoi. However, higher concentrations of iturin A (1.88 mg/l of soil or higher) but not of surfactin (up to 7.5 mg/l of soil) negated the suppression. Growth of Fusarium in liquid cultures was suppressed by iturin A but not surfactin.

Tatsoi [Brassica rapa subsp. narinosa (L.H.Bailey) Hanelt] is a leafy vegetable with potential for cultivation in a riparian wetland ecosystem. The floating culture system has the advantage of ensuring a sufficient water supply in the growing substrate due to the continuous upward water movement caused by capillarity force. This study evaluated the responses of the tatsoi plant to split fertilizer applications under conventional cultivation and floating culture systems. The fertilizer treatments consisted of control (F0), single (F1), split into 2 (F2), split into 3 (F3) or split into 4 applications (F4). The results showed that early growth of tatsoi was better using floating culture than the conventional system. However, tatsoi adapted well to conventional and floating culture systems as long as sufficient nutrients were available. A single application of 6 g NPK fertilizer (16:16:16 v/v/v) at transplanting provided sufficient nutrients, as indicated by the number of leaves, total leaf area, canopy area, stem dry weight, and leaf dry weight at harvest. The leaf SPAD values in the tatsoi plants were higher in the floating culture system than in the conventional system at 14 and 20 DAT fertilized with a 4-split application. Transplanting occurred 14 days after seed planting (DAP), and harvest occurred 49 days later. A quadratic regression model using leaf length (L), leaf width (W), or L×W as predictors was reliable for non-destructive leaf area estimation in the tatsoi plant. It is recommended for farmers to apply a single NPK fertilizer at the rate of 6 g/plant to achieve an optimum yield in tatsoi cultivated using a conventional or floating culture system. HIGHLIGHTS Tatsoi plant grew well under conventional and floating culture systems as long as sufficient nutrients were available Splitting fertilizer into several times of application did not significantly better than single application of NPK fertilizer at time of transplanting SPAD values in the tatsoi leaves were higher in the floating culture than in the conventional system Length and width of leaves were reliable predictors for non-destructive accurate leaf area estimation in the tatsoi plant GRAPHICAL ABSTRACT

A hydroponics system developed using a nutrient film technique was used to evaluate the effectiveness of rice husk biochar (RB) alone or in combination with perlite (PL) as substrates for increasing the growth of leafy vegetables compared with that of PL. Seedlings of cabbage, dill, mallow, red lettuce, and tatsoi were grown hydroponically in PL, RB, and PL + RB (1:1 ratio of PL to RB, v/v) substrates for a 30-d under optimal environmental conditions in a greenhouse. Shoot length and fresh/dry masses of cabbage, dill, and red lettuce plants grown in RB substrate were decreased by 49% on average compared to those plants grown in PL substrate. In contrast, PL + RB substrate led to approximately 2-fold increases in shoot length, number of leaves, and fresh/dry masses of leafy vegetable plants compared with those grown in PL substrate. Foliar nutritional composition (Ca, Mg, K, Na, Mn, Fe, and Zn) and nitrogen status (SPAD index) of plants grown in PL + RB and PL substrates suggested the presence of optimal growth conditions for ensuring optimum yield with high quality. In addition, RB substrate contributed to respective increases of 1.2–3.5-fold in leaf K, Mg, Mn, and Zn contents in most vegetable plants compared with those grown in PL substrate. The RB alone or in combination with PL substrates decreased algal growth in the nutrient solutions as confirmed by scanning electron micrographs of microalgae on the RB surface. The results also indicated that use of PL + RB hydroponic substrate could be an alternative and effective technology for the better management of unwanted algal growth in nutrient solutions and high production of leafy vegetables.

39 p.-7 fig.-2 tab.-9 tab. supl., Microgreens are rich functional crops with valuable nutritional elements that have health benefits when used as food supplements. Growth characterization,nutritional composition profile of 21 varieties representing five species of the Brassica genus asmicrogreens were assessed under light-emitting diodes(LEDs) conditions. Microgreens were grown under four different LEDs ratios(%); red:blue 80:20 and 20:80 (R80:B20 and R20:B80), or red:green:blue 70:10:20 and 20:10:70 (R70:G10:B20 and R20:G10:B70). Results indicated that supplemental lighting with green LEDs (R70:G10:B20) enhanced vegetative growth and morphology, while blue LEDs (R20:B80) increased the mineral and vitamin contents. Interestingly, by linking the nutritional content with the growth yield to define the optimal LEDs setup, we found that the best lighting to promote the microgreen growth was the green LEDs combination (R70:G10:B20). Remarkably, under the green LEDs combination (R70:G10:B20) conditions,the microgreens of Kohlrabi purple, Cabbage red, Broccoli, Kale Tucsan, Komatsuna red, Tatsoi and Cabbage green, which can benefit human health in conditions with limited food, had the highest growth and nutritional content., This research work is a part of a project received seed funding from the Dubai Future Foundation through the Guaana.com open research platform(grant no. MBR026). Dr. Mortaza is supported from ERDF project “Plants as a tool from sustainable global development” No. CZ.02.1.01/0.0/0.0/16_019/0000827.

Microgreens are rich functional crops with valuable nutritional elements that have health benefits when used as food supplants. Growth characterization, nutritional composition profile of 21 varieties representing 5 species of the Brassica genus as microgreens were assessed under light-emitting diodes (LEDs) conditions. Microgreens were grown under four different LEDs ratios (%) (R80:B20, R20:B80, R70:G10:B20, and R20:G10:B70). Results indicated that supplemental lighting with green LEDs (R70:G10:B20) enhanced vegetative growth and morphology, while blue LEDs (R20:B80) increased the mineral composition and vitamins content. Interestingly, combining the nutritional content with the growth yield to define the optimal LEDs setup, we found that the best lighting to promote the microgreen growth was supplying the green LEDs combination (R70:G10:B20). Remarkably, under this proper conditions, Kohlrabi purple, Cabbage red, Broccoli, Kale Tucsan, Komatsuna red, Tatsoi, and Cabbage green had the highest growth and nutritional content profile as microgreens which being a health-promoting in a diet support strategy required for the human health under certain isolated of limited food conditions.

To study the change of the health‐promoting compounds, antioxidant activity and nitrate of tatsoi (Brassica rapa L. ssp. narinosa) caused by different cooking methods. Four cooking methods, that is, boiling, microwave, steaming and stir‐frying were used to treat tatsoi, a leafy Brassica vegetable. All the four cooking methods reduced total soluble sugar, vitamin C and total glucosinolates (GSLs) content. Steaming retained greatest vitamin C and total GSLs content, followed by stir‐frying and microwave. Boiling reduced the antioxidant activity and total phenolic content (TPC). Steaming enhanced the TPC and antioxidant activity. Microwave resulted in great loss of antioxidant activity but not significant change of TPC. No significant change of TPC and antioxidant activity were observed in stir‐fried tatsoi. Boiling led to significant reduction of nitrate, while stir‐frying resulted in significant increase in nitrate, microwave and steaming did not cause nitrate change to significant degree. PRACTICAL APPLICATIONS: There is no consensus regarding the best way to consume thermal‐processed leafy vegetables and the literature pertaining to the preparation of leafy vegetables is still inconsistent. Information on the effects of cooking methods on nutritional properties and antioxidant activity of tatsoi are still limited. The present study will provide cumulative information for the selection of industrial or household cooking methods for the desired quality and products of tatsoi as well as Brassica leafy vegetables.

Bagrada hilaris (Burmeister) (Hemiptera: Pentatomidae) is a serious pest that attacks both germinating and seedling stages of a variety of cruciferous crops grown in the Central Coast of California. B. hilaris feeding on germinating seeds can cause severe stunting and plant mortality, and little is known about the feeding preference of B. hilaris for germinating seeds of major cruciferous hosts and varieties of hosts. No-choice and choice experiments were conducted in which germinating seeds in soilless and soil settings were exposed to B. hilaris adults for 7 days. Susceptibility scores were developed using B. hilaris feeding injury sites, distorted leaves, and deformed and dead plants to determine the overall B. hilaris preference for germinating host seeds. Based on the scores, the order of preference was arugula (Eruca sativa L.) > turnip (B. rapa L. var. rapa) > mizuna (B. rapa L. nipposinica) > kale (B. oleracea L. acephala) > choi (Brassica rapa L. var. chinensis) > broccoli (B. oleracea var. italica Plenck) > cauliflower (B. oleracea L. var. botrytis) > lettuce (Lactuca sativa L.) > sweet alyssum (Lobularia maritima [L.] Desv.). The lowest feeding injury was recorded on germinating lettuce and sweet alyssum seeds. Furthermore, no-choice and choice experiments were conducted with four varieties each of arugula and mizuna, twelve varieties each of kale and choi, and nine varieties/types of leafy Asian greens. The arugula varieties ‘Wild Rocket’ and ‘Spirit’ were more damaged by B. hilaris than other varieties tested. Among mizuna varieties, ‘Beira F1’ was more attractive to B. hilaris than ‘Scarlet’ or ‘Starbor F1.’ The choi varieties ‘Tokyo Bekana,’ ‘Feng Qing Choi F1,’ ‘Joi Choi F1,’ and ‘Win-Win Choi F1’ were more attractive than ‘Rosie F1.’ The leafy Asian greens variety ‘Carlton F1’ was more attractive to B. hilaris than ‘Yukina Savon,’ ‘Tatsoi OG,’ ‘Komatsuna Summerfest F1,’ ‘Red Rain F1,’ and ‘Shungiku.’ Therefore, the results suggest that not all varieties were equally susceptible to B. hilaris feeding and possibly be utilized for further field evaluation as a trap crop or developing more resistant varieties to B. hilaris.

The nutritional composition of ten leafy vegetables (chicory, green lettuce, lamb's lettuce, mizuna, red chard, red lettuce, rocket, spinach, Swiss chard, and tatsoi) and quality traits of the selected leafy vegetables in relation to the light intensity (low and high Photosynthetically Active Radiation; PAR) at time of harvest were determined. Irrespective of the light intensity at time of harvest, the highest leaf dry matter (DM), proteins, nitrate, P, K and Ca contents were observed in rocket followed by mizuna. The highest lipophilic antioxidant activity (LAA) was recorded in red lettuce and rocket, whereas ascorbic acid (AA) and total phenolic (TP) contents of red lettuce were higher compared to the other leafy vegetables. When leafy vegetables were harvested at low as opposed to high PAR, the leaf content was higher in DM, protein, K, Ca and Mg, hydrophilic antioxidant activity (HAA), and LAA by 12.5%, 10.0%, 12.6%, 23.7%, 14.1%, 11.9%, and 18.5%, respectively. The highest values in TP for chicory, green lettuce, lamb's lettuce, mizuna, red chard, and red lettuce, were observed under high PAR.

Germination rates of 11 types of sprout seeds (alfalfa, broccoli, kohlrabi, kyona, mustard, pak choi, red kohlrabi, red radish, red young radish, tatsoi, and violet radish) treated with ClO 2 (200 μg/ml, 5 min) or dry-heat (80 °C/23% relative humidity [RH], 24 h) were determined. Pak choi, red radish, and tatsoi seeds showed highest tolerance to both ClO 2 and dry-heat treatments. Next, pak choi seeds were inoculated with Escherichia coli O157:H7 (5.4 log CFU/g) or Salmonella enterica (4.8 log CFU/g) and sequentially treated with ClO 2 (200 μg/ml, 5 min), drying (45 °C/23% RH, 24 h), and dry heat (80 °C/23% RH, 48 h). E. coli O157:H7 was inactivated, but S. enterica was not eliminated (>3.8 log CFU/g reduction). Pak choi seeds inoculated with the pathogens were treated with ClO 2 , drying, and dry heat and subsequently sprouted for 5 days. When seeds were not completely decontaminated, initial populations of E. coli O157:H7 and S. enterica on seeds ( 5.3 and > 8.4 log CFU/g of sprouts, respectively. This study shows that sequential treatments of pak choi seeds with ClO 2 , drying, and dry heat are effective in reducing large numbers of E. coli O157:H7 and S. enterica without loss of seed viability.

The effects of lactic acid and lemongrass oil treatments on microbial growth in Tatsoi baby leaves were investigated to ensure microbial safety. To determine the optimal concentrations of lactic acid and lemongrass oil as a sanitizer, the effects of several concentrations of lactic acid (0.25, 0.5, 1, and 2 %) and lemongrass oil (0.1, 0.3, 0.5, and 1 %) on aerobic mesophilic bacteria, Salmonella Typhimurium, and Listeria monocytogenes in Tatsoi baby leaves were evaluated. The results showed that the 1 % lactic acid and 1 % lemongrass oil treatment reduced the populations of the microorganisms to the greatest extent. In particular, after the combined treatment with 1 % lactic acid and 1 % lemongrass oil, the count of aerobic mesophilic bacteria was reduced from 7.63 to 2.45 log colony forming unit (CFU) · g−1, and L. monocytogenes was reduced from 6.71 to 1.96 log CFU · g . In addition, S. Typhimurium was not detected in the Tatsoi baby leaves during 7 days of storage. These results suggest that a combined treatment using 1 % lactic acid and l % lemongrass oil could be an effective method for the inactivation of bacteria on the surfaces of Tatsoi baby leaves.

The objective of this study was to evaluate the effects of irradiance levels and spectra produced by solid-state light-emitting diodes (LEDs) on carotenoid content and composition changes in Brassicaceae microgreens. A system of five high-power, solid-state lighting modules with standard 447-, 638-, 665-, and 731-nm LEDs was used in the experiments. Two experiments were performed: (1) evaluation of LED irradiance levels of 545, 440, 330, 220, and 110 μmol m(-2) s(-1) photosynthetically active flux density (PPFD) and (2) evaluation of the effects of 520-, 595-, and 622-nm LEDs supplemental to the standard set of LEDs. Concentrations of various carotenoids in red pak choi and tatsoi were higher under illumination of 330-440 μmol m(-2) s(-1) and at 110-220 μmol m(-2) s(-1) in mustard. All supplemental wavelengths increased total carotenoid content in mustard but decreased it in red pak choi. Carotenoid content increased in tatsoi under supplemental yellow light.

BACKGROUND: The mineral silicon (Si) is an essential element for humans and a general component of the diet found mainly in plant-based foods. The aim of this study was to obtain Si biofortificated leafy vegetables (tatsoi, mizuna, purslane, basil, Swiss chard, and chicory) to use for the fresh-cut products (ready to use). For the production of biofortified plants, a floating system with 0, 50 and 100 mg L −1 of Si in nutrient solution, was used. In addition, the assessment of bioaccessibility of biofortified plants, by in vitro gastro-digestion process, was performed. RESULTS: The added silicon in nutrient solution did not influence yield and colour of vegetables but a species-related accumulation of Si (expressed as SiO2) was found: from 18 to 69 mg kg −1 fresh weight (FW) in tatsoi, from 19 to 106 mg kg −1 FW in mizuna, from 15 to 93 mg kg −1 FW in purslane, from 41 to 294 mg kg −1 FW in basil, from 17 to 76 mg kg −1 FW in Swiss chard, and from 23 to 76 mg kg −1 FW in chicory. The Si became bioaccessible in all species considered in a range from 23% (basil) to 64% (chicory). CONCLUSION: The application of Si to the nutrient solution in the range of 50–100 mg L −1 allows biofortification of leafy vegetables. In addition, the biofortified vegetables showed, on average, more bioaccessible Si, with respect to unbiofortified vegetables. © 2015 Society of Chemical Industry

Edible sprouts are highly nutritious, containing numerous health-promoting phytochemicals and nutrients. However, the process of sprouting is subject to potential contamination by microorganisms attached to the seed coat. The objective of this study was to determine the effects of air anions generated by spray ionization on growth and sterilization of edible sprouts. Treatment with air anions has positive effects on plant growth and sterilization in 4 kinds of sprouts. Hypocotyl length in red cabbage and kale increased approximately 1.26-fold and radicle length of lettuce, red cabbage, and kale increased 1.4 to 1.6-fold compared to the control. The fresh weight of sprouts in the spray-ionization treatment was significantly (16.0-38.5%) higher than that of the controls. Radicle activity in sprouts exposed to anions was higher than that of the control in all species. Bacterial counts on lettuce, red cabbage, and tatsoi decreased significantly (by 41%, 66%, and 19%, respectively), and bacterial colonies also declined in drainage water. Our findings suggest that spray-ionization treatment is useful for improving sprout growth and for sterilizing sprouts.

A novel research of pulsed light-emitting diode (LED) lighting versus continuous lighting was conducted by analyzing phytochemical levels in microgreens. Red pak choi (Brassica rapa var. chinensis), mustard (Brassica juncea L.), and tatsoi (Brassica rapa var. rosularis) were grown indoors under HPS lamps supplemented with monochromatic (455, 470, 505, 590, and 627 nm) LEDs [total photosynthetic photon flux density (PPFD) of 200 ± 10 μmol m–2 s–1, for 16 h day–1]. For pulsed light treatments, the frequencies at 2, 32, 256, and 1024 Hz with a duty cycle of 50% monochromatic LEDs were applied. The results were compared to those under the continuous light (0 Hz) condition in terms of total phenolic content, anthocyanins, and antiradical activity (DPPH). The summarized data suggested that pulsed light affected accumulation of secondary metabolites both positive and negative in microgreens. The significant differences in the response of phytochemicals between pulsed light at several frequencies and continuous l...

This study evaluated the effects of light intensity and the spectrum produced by light-emitting diodes (LEDs) on the growth and nitrate assimilation of tatsoi (Brassica rapa var. rosularis), grown in a controlled environment. A system of high-powered solid-state lighting modules with blue 445, red 640 and 660 and far-red 731 nm LEDs were used for illumination. Two experiments were performed seeking to explore the light parameter effects on tatsoi growth, nitrate, nitrite, total protein, and free amino acid contents, as well as soluble sugar contents and chlorophyll indexes: (1) investigation of the effects of a photosynthetically active photon flux density (PPFD) of 100, 200, 300, 400 and 500 μmol m–2 s–1 and (2) evaluation of the effects of different combinations of red (R660 and R660 + R640), red supplemented with blue (R660 + B445 and R660 + R640+B445) and far red (R660 + R640+B445+FR731) LEDs. A deficient light intensity resulted in nitrate and nitrite accumulation in tatsoi leaves; under the exposure of 100 μmol m–2 s–1 PPFD, tatsoi contained 3.4 times higher NO3 and 34 times higher NO2 contents, compared to that under 200 μmol m–2 s–1. The photosynthetic photon flux density of ∼300 μmol m2 s−1 allowed the obtaining of an optimal tatsoi production with high biomass and minimal nitrate and nitrite contents in the leaves. Long term exposure of sole red light was stressful for tatsoi growth; however the addition of blue light to the red 660- and 640- nm LEDs resulted in the highest total protein and essential amino acid contents, leaf area and biomass, and significantly reduced nitrate but increased nitrite content.

Effects of ultraviolet-C (UV-C) and electron beam irradiation on the quality and microbial populations of leafy vegetables were compared as a microbial decontamination method. Tatsoi and red chard leaves were treated with UV-C at a dose of 5 kJ/m2 or by electron beam irradiation at doses of 0.5, 1, and 3 kGy. After UV-C or electron beam irradiation treatment, the samples were stored at 4 ± 1°C for 11 days. Populations of total aerobic bacteria in leafy vegetables decreased by 0.8–1.1 log CFU/g after treatment with UV-C irradiation, and those of yeast and molds decreased by 1.0–1.8 log CFU/g. On the contrary, electron beam irradiation at 0.5 or 1 kGy reduced the microbial populations by 2.0–2.5 log CFU/g. Electron beam irradiation at 3 kGy eliminated the microorganisms in the samples. These results suggest that electron beam irradiation at low dose below 3 kGy can be more effective than UV-C treatment for the inactivation of microorganisms in Tatsoi and red chard leaves.

The crop species Brassica rapa L. has significant economic importance around the world. However, the global distribution and complex evolutionary history of the species has made investigating its genetic population structure difficult. Crop domestication and improvement has resulted in extreme phenotypic diversity and subspecies that are used for oilseed, food for human consumption, and fodder for livestock. These subspecies include the oilseed morphotypes. oleifera (turnip rape), ssp. dichotoma (brown sarson/toria), ssp. trilocularis (yellow sarson); ssp. rapa (turnip); and Asian leafy vegetables ssp. pekinensis (Chinese cabbage), ssp. chinensis (bok choy), ssp. nipposinica (mizuna/mibuna), ssp. rapifera (rapini/broccoli rabe), ssp. narinosa (tatsoi), ssp parachinensis (choy sum), and ssp. perviridis (komatsuna). To date, studies have had insufficient sampling to determine the relationship of all morphotypes, especially oilseed morphotypes, and questions remain over the contribution of morphotype and geographic origin to population structure. We used genotyping-by-sequencing to score 18,272 single nucleotide polymorphism markers in a globally diverse panel of 333 B. rapa National Plant Germplasm System accessions that included 10 recognized subspecies. Our population genetic and phylogenetic analyses were broadly congruent and revealed five subpopulations that were largely reflective of morphotype and geography. These subpopulations were 1. European turnips/oilseed, 2. Asian turnips/oilseed, 3. yellow/brown sarson (ssp. trilocularis and ssp. dichotoma), 4. Chinese cabbage (ssp. pekinensis), and 5. bok choy, choy sum, and tatsoi (ssp. chinensis, ssp. parachinensis, ssp. narinosa). Additionally, we found evidence of polyphyly and/or paraphyly, particularly for oilseed morphotypes (ssp. oleifera and ssp. dichotoma) and turnips. The results of this study have provided improved resolution to the genetic and phylogenetic relationships of subspecies within the species B. rapa. Understanding of these relationships is key to the future genetic study and improvement of this globally important crop species.

Food industries are increasingly oriented toward new foods to improve nutritional status and/or to combat nutritional deficiency diseases. In this context, silicon biofortification could be an innovative tool for obtaining new foods with possible positive effects on bone mineralization. In this paper, an alternative and quick in vitro approach was applied in order to evaluate the potential health-promoting effects of five silicon-biofortified leafy vegetables (tatsoi, mizuna, purslane, Swiss chard and chicory) on bone mineralization compared with a commercial silicon supplement. The silicon bioaccessibility and bioavailability of the five leafy vegetables (biofortified or not) and of the supplement were assessed by applying a protocol consisting of in vitro gastrointestinal digestion coupled with a Caco-2 cell model. Silicon bioaccessibility ranged from 0.89 to 8.18 mg/L and bioavailability ranged from 111 to 206 μg/L of Si for both vegetables and supplement. Furthermore, the bioavailable fractions were tested on a human osteoblast cell model following the expression of type 1 collagen and alkaline phosphatase. The results obtained highlighted that the bioavailable fraction of biofortified purslane and Swiss chard improved the expression of both osteoblast markers compared with the supplement and other vegetables. These results underline the potentially beneficial effect of biofortified leafy vegetables and also indicate the usefulness of in vitro approaches for selecting the best vegetable with positive bone effects for further in vivo research.

Tatsoi (Brassica narinosa) is a popular Asian salad green that is mostly consumed as a source of fresh produce. The purpose of this study was to assess the microbial diversity of Tatsoi cultivated in a hydroponic system and of its ecosystem. Tatsoi leaves, nutrient solution, and perlite/earth samples from a trickle feed system (TFS) and an ebb-and-flow system (EFS) were collected and their microbial communities were analyzed by pyrosequencing analysis. The results showed that most bacteria in the leaves from the TFS contained genus Sporosarcina (99.6%), while Rhizobium (60.4%) was dominant in the leaves from the EFS. Genus Paucibacter (18.21%) and Pelomonas (12.37%) were the most abundant microbiota in the nutrient solution samples of the TFS. In the EFS, the nutrient solution samples contained mostly genus Rhodococcus and Acinetobacter. Potential microbial transfer between the leaves and the ecosystem was observed in the EFS, while samples in the TFS were found to share only one species between the leaves, nutrient solution, and earth. Together, these results show that the bacterial populations in Tatsoi and in its ecosystem are highly diverse based on the cultivation system.

Object - 10 species of microgreens: amaranth (Amaranthus cruentus L., ‘Red Army’), basil (Ocimum basilicum L., ‘Sweet Genovese’), kale (Brassica oleracea L., ‘Red Russian’), broccoli (Brassica oleracea L.), mustard (Brassica juncea L., ‘Red Lion’), tatsoi (Brassica rapa L., ‘Rosularis’), borage (Borago officinalis L.), beet (Beta vulgaris L., ‘Bulls Blood’), parsley (Petroselinum crispum Mill.) and pea (Pisum sativum L., ‘Meteor’).

The effects of a moderate UV-C pretreatment, a superatmospheric O 2 -enriched modified atmosphere packaging (MAP) and its combination compared to a conventional passive MAP on microbial, health promoting compounds and sensory changes of fresh-cut Tatsoi baby leaves throughout 11 days at 5 °C were investigated. The UV-C and the combined UV-C + O 2 -enriched MAP were the treatments which best controlled the epiphytic microbial growth. Treatment assays did not affect the total chlorophyll and phenolic content and the total antioxidant capacity which were kept throughout storage. According to sensory quality, the shelf life was 9 to 10 days at 5 °C for all treatments. These innovative sustainable combined treatments could be useful to the industry for keeping the overall quality of fresh-cut Tatsoi baby leaves, and probably other leafy vegetables, while minimizing water consumption. Industrial relevance These innovative and sustainable combined treatments could be useful to the industry for keeping the overall quality of fresh-cut Tatsoi baby leaves, and probably other leafy vegetables, while minimizing water consumption. Its application can be easily applied in the industry.

Iturin A and surfactin are antimicrobial lipopeptides produced by antagonistic Bacillus spp. We herein demonstrated that both lipopeptides amended the soil-mediated suppression of the soil-borne disease, Fusarium yellows of tatsoi (Brassica rapa var. rosularis). Significant disease suppression was conferred by the amendments of purified iturin A or surfactin to soil. However, an excess amount of iturin A or surfactin to soil resulted in the loss of disease suppression activity.

Calcium is an essential nutrient for human health, because it is a structural component and takes part in a variety of biological processes. The aim of this study was to increase Ca content of baby leaf vegetables (BLV: basil, mizuna, tatsoi and endive), as fresh-cut products. For the production of biofortified BLV, a floating system with two level of Ca (100 and 200mgL(-1)) in the nutrient solution was used. In addition, the assessment of bioaccessibility of Ca, by in vitro digestion process, was performed. In all vegetables, the Ca biofortification (200mgL(-1)) caused a significant Ca enrichment (9.5% on average) without affecting vegetables growth, oxalate contents and marketable quality. Calcium bioaccessibility ranged from 25% (basil) to 40% (endive) but the biofortified vegetables showed more bioaccessible Ca. These results underline the possibility to obtain Ca biofortified BLV by using agronomic approaches.

Composts, used alone or in mixtures with other materials, can serve as horticultural potting media in organic production systems. In this study, we evaluated the suitability of two locally available composts as media for lettuce and tatsoi produced organically in an unheated greenhouse. One of the composts was produced from food residuals with landscape wastes as a bulking agent, while the other was generated from used horse bedding. Although the two materials had relatively similar total N contents, C:N ratios, and bulk densities, they performed very differently as potting media. Net N mineralization, measured in laboratory incubations, was high in the compost derived from food residuals, but the horse-bedding compost showed net N immobilization, perhaps due to high salinity. Crop production in the food residuals compost was statistically similar to a control treatment consisting of a commercial peat-based potting medium with synthetic fertilizer. Crop growth in the medium consisting of horse-bedding compost, used at 100% or in a 50%/50% mixture with a commercial substrate of bark, peat, and sand, was unacceptable for commercial production. Although the cost per flat of the food residuals compost was slightly higher than that of the commercial peat-based medium, for organic production this additional cost may be insignificant since there are limited potting media options, and price premiums are typically available.

The effect of 1-methylcyclopropene (1-MCP) on shelf life and the ethylene sensitivity of detached leaves from six leafy asian vegetables (Chinese mustard, choy sum, garland chrysanthemum, mibuna, mizuna and tatsoi) commonly used in minimal processing was examined. All vegetables studied were significantly affected by the presence of 1 μl/l ethylene. This reduction was primarily due to yellowing except in mizuna and mibuna. In the absence of ethylene, 1-MCP treatment only increased shelf life for mizuna and tatsoi (21 and 67% increase, respectively). In contrast, 1-MCP treatment in the presence of ethylene significantly protected Chinese mustard, choy sum, garland chrysanthemum and tatsoi. 1-MCP may, therefore, be ideal for use on minimally processed leafy asian vegetables in situations of co-storage or co-retail with ethylene-producing commodities.

ADDITIONAL INDEX WORDS. salinity, salt stress, water reuse, irrigation water, drainage water ABSTRACT. Saline agricultural drainage water may be used as a resource to grow high value horticultural crops and reduce the volume of drainage for eventual disposal. To explore reuse options the effects of salinity and timing of application were tested on selected leafy vegetables grown in 24 sand culture plots in Riverside, Calif. The leafy winter vegetables included 'Ruby Red Chard' Swiss chard ( Beta vulgaris L. var. flavescens (Lam.) Lam.), 'Space' spinach ( Spinacia oleracea L.), 'Vitamin Green' salad greens ( Brassica rapa L. (Narinosa Group)), 'Red Giant' mustard greens ( Brassica juncea L. (Czerniak)), pac choi (Brassica rapa L. (Chinensis Group)), 'Winterbor' kale ( Brassica oleracea L. (Acephala Group)), tatsoi (Brassica rapa L. (Narinosa Group)), 'Salad King' curly endive ( Cichorium endivia L.), and 'Red Preco No. 1' radicchio (Cichorium intybus L.). All vegetables were planted at the same time and irrigated initially with tap water and nutrients. At 3 and 7 weeks after seeding (application times), six salinity treatments were initiated by adding salts to the irrigation water to represent the chemical compositions of drainage waters found typically in the San Joaquin Valley, Calif. The six salinity treatments had electrical conductivities of 3 (control), 7, 11, 15, 19, or 23 dS·m -1 . A randomized complete block design was used with (6 salinities × 2 application times × 2 replications). Within each plot a 1.5-m row of each of the nine vegetables was grown as split plots. Salinity reduced fresh weight (FW) yields of all species. Salt stress applied at 3 weeks after seeding reduced FWs for seven of the nine vegetables compared to salination at 7 weeks. Analyses of salt tolerance curves, maximum yields, and the point of 50% yield reduction (C 50) were conducted. Greens produced the highest biomass at 874 g/plant, but was the most affected by application time. Swiss chard and radicchio were not significantly affected by timing of salinity application, and Swiss chard was the most salt tolerant overall. Greens, kale, pac choi, and to a lesser extent, tatsoi, have potential as winter-grown, leafy vegetables in drainage water reuse systems. markets. Potential crops include winter vegetables, flowers, herbs, medicinals, and other species that are tolerant to drainage water irrigation and would provide high economic return (Shan- non and Grieve, 1999, 2000). In this study, we used synthetic drainage water with ion composition similar to that found typically in the San Joaquin Valley to irrigate nine leafy winter vegetables. The purpose of the study was to determine potential yield and salt tolerance over a range of salinities and to determine if improved yields could be obtained if initial salination were delayed past the early plant establishment stage in which most plants are considered to be salt sensitive (Shannon et al., 1994).

Escherichia coli O157:H7 has been associated in multiple outbreaks linked to the consumption of whole produce and fresh-cut leafy vegetables. However, plant-based foods had not been traditionally recognized as a host for enteric pathogens until the elevated incidence of produce-related outbreaks became apparent. The survival dynamics of two cocktails of generic E. coli (environmental water, plant and soil isolates) and E. coli O157:H7 within the phyllosphere of Mizuna, Red Chard and Tatsoi during their production, harvest, minimal processing, packaging and storage over two greenhouse production cycles were studied. Genotyping of applied generic E. coli strains to evaluate their comparative survival and relative abundance in the phyllosphere by REP-PCR is also reported. The Mizuna, Red Chard and Tatsoi shoots were grown under standard greenhouse conditions and fertility management. Both E. coli cocktails were spray-inoculated separately and determined to result in an initial mean population density of log 4.2 CFU/cm2. Leaves were harvested as mini-greens approximating commercial maturity, minimally processed in a model washing system treated with 3 mg/L of ClO2 and stored for 7 days at 5 °C. Rapid decline of generic E. coli and E. coli O157:H7 populations was observed for all plant types regardless of the leaf age at the time of inoculation and the irrigation type across both seasonal growth cycle trials. The decline rate of the surviving populations for the fall season was slower than for the summer season. The minimal processing with 3 mg/L of ClO2 was not sufficient to fully disinfect the inoculated leaves prior to packaging and refrigerated storage. Viable populations of E. coli and E. coli O157:H7 were confirmed throughout storage, including the final time point at the end of acceptable visual leaf quality. In this study, the ability of low populations of E. coli to survive during production and postharvest operations in selected mini-greens has been demonstrated. However, further field-based trials are needed to expand understanding of the post-contamination fate of enteric bacterial pathogens on leafy vegetables. In summary, this research work provides baseline data upon which to develop food safety preventive control guidance during the production and minimal processing of these crops.

The aim of the present study was to evaluate the usefulness of Brassica rapa var. narinosa for field production in Central European climatic zone in order to introduction of this species to large-scale farming. Chinese flat cabbage cultivars, ‘Tatsoi’ and ‘Misome’, were the object of the 2-year-long field experiment in south Poland, conducted in 2 terms: plantings in the middle and at the end of August, harvests in the middle of September and on the beginning of October (1st and 2nd growing period, respectively). Plants were evaluated for morphological and chemical variability at the transplant stage. The yield and bioactive compounds content in the leaf petioles of mature plants were also studied. Analyses of juvenile plants, conducted before transplanting, showed that ‘Misome’ transplants were greater, but they had less leaves then ‘Tatsoi’. Transplants of both cultivars from the 2nd growing period had greater fresh weight, but the content of dry matter, soluble sugars and carotenoids was lower. Total and marketable yield, rosette mass, L-ascorbic acid and crude fibre content were greater for both cultivars planted in the middle of August and harvested in the middle of September. Leaf petioles of Chinese flat cabbage from the 2nd growing period were significantly richer in dry matter and soluble sugars. Only the level of carotenoids and chlorophylls was not influenced by the growing period. ‘Misome’ gave the greater marketable yield of better structure, and had a higher content of biologically active compounds than ‘Tatsoi’, with the exception of crude fibre. In Central Europe conditions, this cultivar should be recommended for plantings in the middle of August to achieve the best yields of high nutrient content.

Tatsoi (Brassica narinosa L.H. Bailey), also called spinach mustard or spoon mustard, is cultivated for edible greens in Asia. In Korea, this plant has recently become popular as a sprout vegetable that is grown to harvestable size in 5 to 6 days. During April 2012, tatsoi seedlings showing typical symptoms of downy mildew were found in plastic greenhouses in Pyeongtaek City of Korea. Infection resulted in chlorotic areas on the leaves with a white mildew developing on the abaxial surface, and finally led to necrosis of the lesions. Affected sprouts were unmarketable and abandoned without harvesting. A sample was deposited in the Korea University herbarium (Accession No. KUS-F26445). Microscopic examination of fresh material was performed under a light microscope. Conidiophores emerging from stomata were hyaline, 270 to 550 × 10 to 25 μm, straight, and monopodially branched in six to eight orders. Ultimate branchlets were mostly in pairs, flexuous, and 15 to 25 μm long. Conidia were hyaline, subglobose, and 20.5 to 26.5 × 19.5 to 24.5 μm with a length/width ratio of 1.05 to 1.20. These characteristics unequivocally indicate the genus Hyaloperonospora (1). Previously H. parasitica (formerly under Peronospora) has been considered a causal agent of downy mildew on tatsoi (2,4), but the present Korean accession is morphologically distinct from the former species by possessing subglobose conidia with a low length/width ratio. To confirm this morphological difference, amplification and sequencing of the internal transcribed spacer (ITS) region of rDNA of the Korean specimen were performed using procedures outlined by Göker et al. (3). The resulting 874-bp sequence of the region was deposited in GenBank (Accession No. JX401551). A comparison with the ITS sequences available in the GenBank database revealed that it was identical to Hyaloperonospora brassicae found on Brassica oleracea var. italica (EU137726), and showed only one base pair substitution compared to pathogens from B. rapa ssp. pekinensis (JF975613) and B. napus spp. napus (EU049248), but is significantly different from H. parasitica on Capsella bursa-pastoris (AY210988) with a base-pair dissimilarity of about 13%. Therefore, the pathogen found in Korea was confirmed to be H. brassicae. Pathogenicity was demonstrated by shaking diseased leaves onto the leaves of healthy tatsoi seedlings, incubating the plants in a dew chamber at 20°C for 24 h, and then maintaining them in a greenhouse (22 to 26°C). After 3 days, inoculated plants developed downy mildew symptoms from which identical fungi were observed, thus fulfilling Koch's postulates. Control plants treated with sterile water did not develop any symptoms or signs of downy mildew. This is the first report of a downy mildew on tatsoi in Korea, although it has been found in China (2) and Japan (4). To our knowledge, there is no record of tatsoi downy mildew outside East Asia (2,4). References: (1) O. Constantinescu and J. Fatehi. Nova Hedwigia 74:291, 2002. (2) D. F. Farr and A. Y. Rossman. Fungal Databases, Systematic Mycology and Microbiology Laboratory, ARS, USDA. Retrieved from http://nt.ars-grin.gov/fungaldatabases/ July 18, 2012. (3) M. Göker et al. Mycol. Res. 113:308, 2009. (4) M. Satou et al. Annu. Rep. Soc. Plant Protect. N. Jpn. 50:62, 1999.