Hiroshi Ehara

Prof. Dr. Hiroshi Ehara

orcid

Research Focus & Metrics

Academic Career Length

28Years (1999-Present)

(Calculated once Scilit publication data is synced: current year − year of first publication + 1)

Representative Publications

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12 December 2019 in Plant Production Science
Verified
Journal Article
Open access
JYJunko Yoshida
Junko Yoshida
NTNorihiko Tomooka
Norihiko Tomooka
TKThet Yee Khaing
Thet Yee Khaing
PSP. G. Sunil Shantha
P. G. Sunil Shantha
HNHitoshi Naito
Hitoshi Naito
HEHiroshi Ehara
Hiroshi Ehara
The genus Vigna contains important crops such as cowpea and mungbean. Wild Vigna showing higher salt tolerance than Vigna crops were screened and their tolerance mechanisms are discussed. Primary screening using 7 Vigna crops and 23 wild Vigna under 300 mM NaCl selected V. luteola, V. marina and V. vexillata. A study under different salt concentrations revealed the highest survival ability of V. marina. Diversity of salt tolerance in each species was revealed using a total of 230 accessions. Growth and physiological responses under 150 mM NaCl were then compared using two selected accessions from each species. The pattern of Na+ accumulation in roots, stems and leaves suggested that V. vexillata (V1) and V. luteola (L8, L9) are ‘Na+ excluder’ type, while V. marina (M1, M4) is ‘Na+ includer’ type. V. luteola (L8, L9) showed the highest dry matter production under control condition and well-maintained shoot dry weight under salt stress. Interestingly, V. luteola (L9) accumulated the highest Na+ in roots (3000 μM g−1) and increased root dry weight under salt stress, which might work as Na+ reservoir restricting Na+ transition to the leaves, leading to the increased photosynthetic rate. V. luteola has great potential in areas where moderate salt damage occurs. V. marina (M1, M4) accumulated Na+ at high level in roots, stem, and leaves. Under salt stress, they increased stomatal conductance, transpiration rate, and photosynthetic rate, which suggested the adaptational regulation of aquaporin gene expression. V. marina will be useful as food, pasture and phytoremediation legumes in highly salt-damaged areas.

26 April 2022 in PLOS ONE
Verified
Journal Article
Open access
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OTOrnprapa Thepsilvisut
Ornprapa Thepsilvisut
PCPreuk Chutimanukul
Preuk Chutimanukul
Sudathip Sae-tanSudathip Sae-tan
Sudathip Sae-tan
HEHiroshi Ehara
Hiroshi Ehara
One of the key components that affects soil productiveness, plant growth, and crop quality is fertilization. The effect of fertilizer, both organic and chemical, on the extremely acidic (pH 4.10) sandy loam soil chemical properties, yield, and quality of white mugwort grown were evaluated in this study. The field experiment arranged in a randomized complete block design, with four replications was conducted in Prachin Buri province, Thailand. There were six treatments, no fertilization (control), chemical fertilizer (25-7-7 + 46-0-0) applied at 187.50 (66.56 N:6.77 P2O5:6.77 K2O kg ha-1) kg ha-1 and applied at 375.00 (133.12 N:13.13 P2O5:13.13 K2O kg ha-1) kg ha-1, chicken manure applied at 3.36, 6.72, and 10.08 t ha-1. After harvesting, application of chicken manure tended to increase soil organic matter compared to the control, however, the application of chemical fertilizer did not show the same effect. The fresh weight of white mugwort increased with the rise in both fertilizer levels. Chicken manure application at 10.08 t ha-1 produced the highest fresh weight at all times. The level of accumulated nitrate was significantly greater when fertilizer rates increased. In addition, the total phenolic content of the white mugwort fertilized with chicken manure was higher than that fertilized with chemical fertilizer. However, there was no association between the DPPH radical scavenging capacity at harvesting times and different fertilization. Based on the results, chicken manure applied at 10.08 t ha-1 gave the best yield and higher total phenolic content of white mugwort, which was probably due to the improved soil organic matter.

3 October 2024 in Horticulturae
Verified
Journal Article
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PCPanita Chutimanukul
Panita Chutimanukul
PPPakin Piew-ondee
Pakin Piew-ondee
TDThanyaluk Dangsamer
Thanyaluk Dangsamer
ATAkira Thongtip
Akira Thongtip
SJSupattana Janta
Supattana Janta
PCPreuk Chutimanukul
Preuk Chutimanukul
Radish (Raphanus sativus L.) is highly nutritious and contains antioxidants that help reduce the risk of diseases. Light is a crucial factor in their growth and the stimulation of secondary metabolite production. Therefore, this study aimed to investigate the effects of light spectra on the development, physiological responses, and antioxidant capacity of radish varieties including cherry belle (CB), black Spanish (BS), hailstone white (HW), Malaga violet (MV), and sparkler white tip (SW) under a controlled environment. Various spectra of red (R), green (G), and blue (B) light were used. The study found that using a combination of red and blue light (3R:1B) resulted in the highest growth in root diameter, fresh weight, and dry weight across all five radish varieties, with values ranging from 1.83 to 4.63 cm, 13.58 to 89.33 g, and 1.20 to 4.64 g, respectively. In terms of physiological responses, the CB and BS varieties showed a higher photosynthetic rate after exposure to mixed red and blue light (1R:3B, 3R:1B). Additionally, adding green light to the red and blue light also enhanced the photosynthetic rate, with statistically significant differences ranging from 3.31 to 3.99 µmol m−2 s−1. The SW variety of radish exhibited an increase in phenolic compounds, flavonoids, and anthocyanins when exposed to light spectra of 1R:1G:1B, 1R:2G:1B, 1R:3G:1B, and 1R:3B. The highest levels of phenolic compounds were 4.67–5.14 mg GAE/g DW, flavonoids were 1.62–1.96 mg Rutin/g DW, and anthocyanins were 1.20–1.58 µg/g DW. However, the antioxidant capacity of five radish varieties under different light spectra did not show significant differences. Thus, the growth, photosynthesis, and antioxidant capacity depend on the optimal light spectrum for each radish variety.

1 August 2023 in Horticulturae
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Journal Article
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OTOrnprapa Thepsilvisut
Ornprapa Thepsilvisut
NSNipawadee Sukree
Nipawadee Sukree
PCPreuk Chutimanukul
Preuk Chutimanukul
DADusit Athinuwat
Dusit Athinuwat
WCWilawan Chuaboon
Wilawan Chuaboon
HEHiroshi Ehara
Hiroshi Ehara
The growing media is one of the significant elements affecting microgreens’ yield and quality. This experiment investigated the possibility of waste utilization instead of employing peat moss to produce sunflower and water-spinach microgreens. The treatments consisted of peat moss (Control), coconut coir dust (CD), leaf compost (LC), food waste compost (FC), CD:LC = 1:1 v/v, CD:FC = 1:1 v/v, LC:FC = 1:1 v/v, and CD:LC:FC = 1:1:1 v/v. The results proved that the highest yield of sunflower microgreens was observed when cultivated in 1:1 v/v of CD:LC media (10,114.81 g m−2), whereas the highest yield of water spinach microgreens was recorded under the treatments of CD, Control, 1:1 v/v of CD:LC, and 1:1:1 v/v of CD:LC:FC media (10,966.67–9800.00 g m−2). The biochemical composition of the microgreens varied within the types. Our findings demonstrated that a tendency of an increase in chlorophyll and carotenoid contents depended on the growth of both microgreens under different growing media. All growing media did not cause excess nitrate residue or pathogenic contamination in both microgreens, namely Clostridium perfringens, Salmonella spp., and Staphylococcus aureus. In contrast, almost all the growing media resulted in a higher population of Bacillus cereus contamination in both microgreens than the standard set limit, except for sunflower microgreens grown in the control and CD growing media. These findings could suggest that the 1:1 v/v of CD:LC and CD media were the most effective growing media for sunflower and water spinach microgreens, respectively, but further cleaning before consumption is recommended to avoid or reduce the foodborne incidences caused by B. cereus in microgreens.

13 October 2023 in Horticulturae
Verified
Journal Article
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PCPreuk Chutimanukul
Preuk Chutimanukul
SSSiripong Sukdee
Siripong Sukdee
OPOnmanee Prajuabjinda
Onmanee Prajuabjinda
OTOrnprapa Thepsilvisut
Ornprapa Thepsilvisut
SPSumalee Panthong
Sumalee Panthong
PCPanita Chutimanukul
Panita Chutimanukul
Hericium erinaceus (Bull.:Fr) Pers. is a medicinal mushroom that has various health benefits and is a rich source of bioactive compounds and antioxidant activity. In recent years, H. erinaceus has been considered for its many medicinal properties and is widely consumed in Asian countries. This work aimed to explore the potential improvement of coconut water utilization in order to promote growth and increase the yield, as well as the enhancement of bioactive compounds and antioxidant activity of H. erinaceus. The application of coconut water at a concentration of 20% (v/v) resulted in the optimal development and production of H. erinaceus. In terms of biological efficiency, it was demonstrated that the 22.09% increase over the control treatment resulted in a higher yield. Moreover, H. erinaceus cultivated from coconut water intake at all concentrations resulted in higher protein content. Additionally, bioactive compounds such as total triterpenoid content and total phenolic content of H. erinaceus were 67.87–89.24 mg Urs/g DW and 16.62–17.39 mg GAE/g DW, respectively, while H. erinaceus grown on a control treatment had the lowest at 56.84 mg Urs/g DW and 14.42 mg GAE/g DW, respectively. Applying coconut water at all concentrations resulted in H. erinaceus IC50 values of 0.58–0.69 mg/mL exhibiting higher DPPH activities than those grown on control treatment IC50 value of 0.77 mg/mL. Therefore, this finding of the study indicated that the utilization of coconut water as a therapy resulted in a significant enhancement in the development, production, and bioactive compounds of H. erinaceus, in comparison to the control treatment.

17 August 2020 in Plant Production Science
Verified
Journal Article
Open access
AAAidil Azhar
Aidil Azhar
DMDaigo Makihara
Daigo Makihara
HNHitoshi Naito
Hitoshi Naito
KAKoki Asano
Koki Asano
MTMai Takagi
Mai Takagi
HEHiroshi Ehara
Hiroshi Ehara
Sago palm (Metroxylon sagu Rottb.) photosynthetic performance was evaluated under drought conditions through leaf gas exchange and chlorophyll a fluorescence measurement. Drought has an impact on sago palm’s leaf gas exchange parameters and its chlorophyll fluorescence of PSII. Stomatal limitations were found to be the main factor limiting photosynthetic activities of sago palm under drought conditions. Photosynthetic rate decreased following the inhibition in the PSII reaction center. Early detection of interference upon the efficiency of the PSII reaction center due to drought stress was recorded by chlorophyll a fluorescence measurement. Graphical abstract /I–light response curve of chlorophyll a fluorescence, C i–intercellular CO2 concentration, E–transpiration rate, Eopt–optimum irradiance, ETR–electron transport rate, ETRmax–maximum electron transport rate, gs –stomatal conductance, I max–maximum irradiance, NPQ–non-photochemical quenching, P N–net photosynthetic rate, P N/I–light response curve of net photosynthetic rate, P N (Imax)–maximum value of P N obtained at maximum irradiance, WUE–water use efficiency, Y (II)–effective quantum yield of PSII, α–asymptotic photosynthetic efficiency, Φ(Icomp-I200)–quantum yield at the range between light compensation point and 200 µmol m−2 s−1 irradiance.