論文 - 真田 篤史
-
Atsushi Sanada and Shinsuke Agehara
plants 12 2023年01月
担当区分：筆頭著者 記述言語：英語 掲載種別：研究論文（学術雑誌）
Tryptophan is a precursor of indole-3-acetic acid (IAA), which is the major auxin involved in the regulation of lateral root formation. In this study, we used a scanner-based rhizotron system to examine root growth and morphological responses of soybean (Glycine max, ‘Golden Harvest’) seedlings to exogenous tryptophan. Seeds were sown directly in the rhizotron filled with field soil. Tryptophan was applied at 1.9 and 3.8 mg plant−1 by soil drenching or foliar spray. Canopy and root projected area were monitored by analyzing canopy and rhizotron images using ImageJ software. Seedlings were sampled at the first trifoliate stage, 18 days after sowing (DAS), and root morphology was determined by analyzing washed root images using WinRHIZO software. According to contrast analysis, when all tryptophan treatments were pooled, tryptophan application increased canopy and root projected area by 13% to 14% compared with the control at 18 DAS. Tryptophan application also increased root dry matter accumulation by 26%, root:shoot ratio by 24%, and secondary root number by 13%. Tryptophan applied by soil drenching also increased root length and surface area of fine roots (<0.2 mm diameter) by 25% and 21%, respectively, whereas it slightly inhibited primary root elongation. The efficacy of tryptophan soil drenching in stimulating root formation became greater with increasing the application rate. These results suggest that exogenous tryptophan induces auxin-like activities in root development. Soil drenching of tryptophan appears to be an effective strategy in improving the establishment of soybean. Importantly, this strategy is easily implementable by commercial growers with no negative side effect.
-
根箱とImageJを用いた迅速かつ安価なダイズ （Glycine max） の根および地上部の生育評価手法の確立 査読あり 国際共著
揚原 晋輔, 真田 篤史
根の研究 29 ( 1 ) 5 - 19 2020年03月
担当区分：最終著者, 責任著者 記述言語：日本語 掲載種別：研究論文（学術雑誌） 出版者・発行元：根研究学会
<p>著者らは，根箱のスキャン画像解析に基づいた，非破壊によるダイズ （<i>Glycine max</i>） の根の解析手法を確立した．使用した根箱は，木枠とアクリル板で構成された．本研究の主な目的は，初期生育時における野菜苗の根および地上部の発達を，根箱と，フリーソフトである画像解析ソフトImageJを用いて，迅速かつ安価に評価する手法を確立することであった．ダイズは，根箱に播種後，根とキャノピー画像を経時的に調査し，18日目に抜き取った．根の投影面積は，ImageJと2つの市販ソフト （栽培中の画像はWinRHIZO Tron，抜き取り後の画像はWinRHIZO） で測定された．栽培中にImageJとWinRHIZO Tronで測定した根の投影面積は，単回帰分析の結果，決定係数が0.566～0.751の間を示し，有意な相関関係が認められた．また，ImageJと卓上葉面積計で測定した葉面積は，決定係数が0.678であった．したがって，ImageJの測定値は，栽培中の根の投影面積と葉面積の発達を相対評価する指標として利用しうると考えられた．さらに，WinRHIZO Tronは1つの画像解析に約60分要することがあり，ImageJ （1つの画像解析に対し2～3分） と比べて測定項目は多岐にわたるが多大な時間と労力を要した．抜き取り後にImageJとWinRHIZOで測定した根の投影面積は，単回帰分析の結果，高い決定係数 （0.919） を示し，ImageJでも抜き取り後の根の評価が可能であることを示した．したがって，本研究で用いた根箱とImageJによる画像解析は，ダイズの根および地上部の発達を非破壊的に迅速かつ安価に評価し得ることが示された．</p>
DOI： 10.3117/rootres.29.5
-
Enhancing salinity tolerance in tomatoes at the reproductive stage by increasing pollen viability 査読あり 国際誌
Nasratullah Habibi, Mohammad Yosuf Fakoor, Shah Mahomoud Faqiri, Zarir Sharaf, Mohammad Sadiq Hotak, Nelofar Danishyar, Mohammad Mustafa Haris, Khuwaja Safiullah Osmani, Takashi Shinohara, Naoki Terada, Atsushi Sanada, and Kaihei Koshio
Bionatura 8 ( １ ) 2023年03月
記述言語：英語 掲載種別：研究論文（学術雑誌）
This study was conducted to mitigate the adverse effects of sodium chloride stress on the reproductive parameters of tomatoes. This experiment was conducted in the greenhouse of the laboratory of tropical horticultural science, department of International agricultural development, Tokyo University of Agriculture. The design was a factorial CRD (completely randomized design) with five sodium chloride (0 mM, 50 mM, 100 mM, 150 mM, and 200 mM) treatments and four primings (0 MPa, 0.4 MPa, 0.8 MPa, and 1.2 MPa) treatments. Micro-Tom seeds were soaked in polyethylene glycol (PEG6000). Salinity was applied through irrigation water when the first flower bloomed. Reproductive-related parameters such as the number of flowers per plant, pollen viability, pollen germination, pollen tube length, number of fruits per plant, fruits size and yield per plant were measured. It was observed that salinity affected the tomato plants severely during the flowering stage, and many flowers did not bear fruit due to the decrease in pollen viability. In addition, electrolyte leakage increased under salt stress, while priming decreased this parameter. Priming improved the number of flowers, pollen viability, and fruits per plant. The best priming treatments were 0.8 MPa and 1.2 MPa for promoting and enhancing tolerance in the reproductive stage.
-
Naoki Terada, Kalara Dissanayake, Chiharu Okada, Atsushi Sanada and Kaihei Koshio
horticulturae ９ ( 367 ) 2023年03月
記述言語：英語 掲載種別：研究論文（学術雑誌）
Fertilization is essential for the optimal growth and development of crops; however, the amount of fertilizer can cause positive or negative effects depending on its rate. In addition, the culti-vation system plays a significant role in determining vegetative growth and fruit quality. Therefore, the objectives of this study were to examine the Micro-Tom response to different fertilization rates (first experiment), and to assess the effect of three different cultivation systems on its growth, yield, and fruit quality (second experiment). The fertilization rates used were (A) no fertilizer application control, (B) 0.026 g L−1, (C) 0.052 g L−1, (D) 0.13 g L−1, (E) 0.26 g L−1 standard, (F) 0.52 g L−1, and (G) 1.3 g L−1, and the cultivation systems were conventional, organic, and hydroponic. The results of the first experiment showed that plant growth and yield of Micro-Tom were highly influenced by the fertilization rate and Micro-Tom recorded the highest yield at 0.52 g L−1. In terms of the second experiment, the hydroponically grown Micro-Tom tended to accumulate amino acid, while organic and conventional systems showed more accumulation of sugars and organic acid; the highest yield was recorded in the hydroponic system. The yield obtained in the hydroponic systems was more than double that of the soil cultivation methods. The findings of this study can contribute to promoting the organic and hydroponic cultivation of tomatoes.
-
Influence of the Hypobaric Method in Physicochemical Fruit Quality Traits of Yellow and Purple Passion Fruit Stored in Cold Temperature 査読あり
Viera William, Shinohara Takashi, Sanada Atsushi, Terada Naoki, Koshio Kaihei
The Horticulture Journal advpub ( 0 ) 2023年
記述言語：英語 出版者・発行元：The Japanese Society for Horticultural Science
<p>Passion fruit (<i>Passiflora edulis</i>) is a tropical fruit that can be consumed fresh or processed. It is a typical respiratory climacteric fruit which is highly perishable because of the loss of water that causes dehydration and thus shrinkage, affecting the fruit appearance; in addition, some quality traits such as fruit weight, firmness and vitamin C content can also be influenced. Therefore, this fruit has a short shelf life. Storage in low temperatures has been assessed to extent the passion fruit shelf life remaining its fruit quality traits; however, information about the application of the hypobaric method in this fruit is null. The objective of this research was to evaluate the physical and chemical characteristics of the yellow and purple passion fruit under hypobaric storage conditions in low temperature. Results showed the hypobaric method had a positive effect in decreasing fruit weight loss, declining the loss of firmness, and reducing the degradation of vitamin C during the storage period. It decreased the evolution of ethylene which is positive to delay fruit senescence, and the production of CO<sub>2</sub>. Finally, it was the only method which avoids the shrinkage completely in the purple passion fruits (‘Gulupa’, ‘Summer Queen’, and ‘Ruby Star’) and showed minor shrinkage in ‘POR1’ (yellow passion fruit). This method is considered as a promising technique to improve fruit storage.</p>
DOI： 10.2503/hortj.qh-081
-
Estimating irrigation water amounts for tomato cultivation using observed meteorological data in Djibouti 査読あり
WATANABE Fumio, SUZUKI Shinji, MOHAMED Tabarek Ismael, JITSUNO Masataka, OHSHIMA Hiroyuki, SANADA Atsushi, SHINOHARA Takashi, ABDALLAH Abdillahi Houssein
Journal of Arid Land Studies 32 ( S ) 95 - 99 2022年12月
記述言語：英語 掲載種別：研究論文（国際会議プロシーディングス） 出版者・発行元：The Japanese Association for Arid Land Studies
<p>Irrigation is essential for crop cultivation in arid and semi-arid areas with limited rainfall and water resources. Efficient and effective use of water resources is required and saving irrigation water is important. Djibouti is a very dry region with annual rainfall of about 150 mm and an average annual temperature of 28.6°C. Due to such meteorological conditions, water resources depend mostly on groundwater, and this makes water extremely scarce. Therefore, water saving in agricultural sector is indispensable. This study aims at promoting effective and efficient use of irrigation water in Djibouti. The appropriate irrigation water amounts for tomato cultivation were estimated using CROPWAT provided by FAO and observed meteorological data at Ali Farren farm in Djibouti. The conditions required for calculating the amounts of irrigation water were medium loam soil based on the laboratory results of soil particle size test, and the tomato cultivation period from October to March according to the local farmers. The result showed that the average monthly reference evapotranspiration was 5.7 mm/day annually. Reference Evapotranspiration was maximum in July and August with 8.4 mm/day and minimum in December with 4.6 mm/day. The amount of irrigation water from October to March was about 476 mm which corresponds to the local tomato cultivation period.</p>
-
William Viera, Takashi Shinohara, Atsushi Sanada, Naoki Terada, Lenin Ron and Kaihei Koshio
horticulturae 8 2022年08月
記述言語：英語 掲載種別：研究論文（学術雑誌）
Seed is a fundamental tool to carry out breeding processes and for the propagation of the crops; however, seed propagation generally has low and irregular germination. Passion fruit (Passiflora) species are economically important for Ecuador, which is the main exporter of passion fruit concentrate in Latin America. Ecuadorian farmers propagate new plants by seeds to establish new passion fruit orchards or to extend their cultivated area. The objective of this research was to determine the differences in germination and seedling development with the application of priming methods in five genotypes of passion fruit belonging to three different taxa that are of commercial use in Ecuador. The genotypes used were: INIAP 2009 and P10 (P. edulis f. flavicarpa), Gulupa (P. edulis f. edulis), and local germplasms POR1 (P. edulis f. flavicarpa) and PICH1 (P. maliformis). The priming methods were: water (control), hydrogen peroxide at 15%, potassium nitrate at 1%, PEG 6000 at−1.2 MPa, and gibberellic acid at 500 ppm. The results showed that there was a genotype-response depending on the priming method. Nevertheless, Polietilenoglicol (PEG 6000) could be considered as a promising method to encourage seed germination and promote seedling growth in the Passiflora species. More research regarding the use of this compound has to be carried out in order to determine in depth the physiological processes related to its functions to improve seed germination as well as production of vigorous seedlings.
-
William Viera, Takashi Shinohara, Iván Samaniego, Naoki Terada, Atsushi Sanada, Lenin Ron and Kaihei Koshio
plants 11 2022年03月
記述言語：英語 掲載種別：研究論文（学術雑誌）
There are several species of passion fruit grown in South America. However, there is a lack of information about the mineral content in their pulp. Thus, the objective of the present research was to determine the mineral content in the pulp of different germplasms of passion fruit [Passiflora edulis f. flavicarpa (INIAP 2009 and P10), P. alata (Sweet passion fruit), P. edulis f. edulis (Gulupa) and Passiflora sp. (Criollo POR1 and Criollo PICH1)] grown in Ecuador and to determine their relationship with relevant fruit quality traits. The results showed that high Mg content was associated with less peel thickness, soluble solids was negatively related to K and B content, and vitamin C was negatively related to S content. INIAP 2009 had high titratable acidity and fruit weight but low N and Na; P10 showed the highest contents of N, K, Na, Mn and fruit weight but less P, Mg, and Fe; sweet passion fruit showed high S, Zn, Cu, soluble solids, and peel thickness but low K, Ca, B, and titratable acidity; Gulupa had high Mg, B, and Zn but low S, Fe, and Mn; Criollo POR1 showed high N and Fe but low Zn; and Criollo PICH1 showed high P, Ca, Mg, and Cu but low soluble solids and peel thickness. These results provide additional information on passion fruit germplasm grown in Ecuador and constitutes a reference for further breeding programs.
-
Abdelazize Eljiati, Imtiaz Ahmed, Naoki Terada, Atsushi Sanada, Kaihei Koshio
Atlas Journal of Biology 2022 752 - 758 2022年03月
記述言語：英語 掲載種別：研究論文（学術雑誌）
After pollination, aborted date fruits known as tri-carpel or shiss, remain on the bunch in most of the varieties and exert a competition on fruits for water and nutrients. In Sukkary, they drop down at the end of kimri stage, while remain on ‘Khlass’ until the harvest. Most of them remain as bisr and little turns into tamr that is not appreciated in the date market. They can only be used as paste that has low price compared to dates. In an attempt to get rid of shiss, we sprayed Ethephon at different concentrations on bunches of ‘Sukkary’ and ‘Khlass’ after fruit-set, at hababook stage. Beside the shiss drop, undesirable fruit drop also occurs. We are looking for the optimum Ethephon concentration where shiss dropped more than fruits. In ‘Khlass’, the Ethephon concentration 800 ppm showed the highest shiss drop (81%) together with a fruit drop of 20% that occurs at the same time, while in ‘Sukkary’, the concentration of 600 ppm was the best by giving a shiss drop equal to 44 % together 12% fruit drop. We consider that the concentration of 800 ppm at hababook stage is the ideal concentration to generate optimum drop in shiss with reasonable percentage of fruit drop. We, therefore highly recommend a trial with this concentration on ‘Sukkary’ as well.
DOI： 10.5147/ajb.vi0.229
-
Phytochemical Composition and Antioxidant Activity of Passiflora spp. Germplasm Grown in Ecuador 査読あり 国際誌
William Viera, Takashi Shinohara, Iván Samaniego, Atsushi Sanada, Naoki Terada, Lenin Ron, Alfonso Suárez-Tapia and Kaihei Koshio
plants 11 2022年01月
記述言語：英語 掲載種別：研究論文（学術雑誌）
Tropical fruits are in high demand for their flavor and for their functional composition because these compounds are considered nutraceuticals. Passion fruit production is of economic importance to Ecuador; however, several Passiflora species are grown and each has to be analyzed to identify their phytochemical composition. In this study, the polyphenol, flavonoid, carotenoid, vitamin C, sugar and organic acid contents were determined. Six different Passiflora spp. germplasms were analyzed, coming from Passiflora edulis f. flavicarpa, Passiflora alata, Passiflora edulis f. edulis and unidentified Passiflora species (local germplasm). Measurement techniques included reflectometry for vitamin C, spectrophotometry for antioxidant compounds and HPLC for sugars and organic acids. Data were analyzed by principal component analysis, correlation and analysis of variance. Results showed that INIAP 2009 and P10 showed a high amount of polyphenols, antioxidant activity and citric content. Sweet passion fruit had the lowest vitamin C content while Gulupa showed the highest content. In terms of the local germplasm, POR1 showed the lowest content of flavonoids while PICH1 had high flavonoid and carotenoid content. Polyphenols were the main compounds that influenced antioxidant activity. This phytochemical information adds value to passion fruit as a nutraceutical source.
-
Kiyotaka OHO, Nasratullah HABIBI, Trizhia Marie Bool SILVA, Naoki TERADA, Atsushi SANADA, Takashi SHINOHARA, Hiroshi GEMMA, Kaihei KOSHIO
Journal of ISSAAS 28 ( 1 ) 34 - 50 2022年
記述言語：英語 掲載種別：研究論文（学術雑誌）
Jaboticaba is a sub-tropical fruit native to Brazil, that is cultivated in South America and Southeast Asia etc. One of the barriers for commercializing this fruit is the difficulty in distinguishing the fruit maturation stages and the fruit cannot be kept on the tree for a long time due to rapid maturation. This study aimed to understand the comprehensive maturation mechanism and make use of maturation indicators to determine the harvesting time. The primary metabolites were analyzed at three different maturation stages using high performance liquid chromatography (HPLC) and gas chromatography - mass spectrometry (GC-MS) as a data driven research. Metabolite analysis revealed the amount and the changes in individual metabolites and metabolic pathways such as the tricarboxylic acid cycle (TCA cycle), anaerobic respiration, shikimate pathway, and γ- aminobutyric acid (GABA) shunt in the process of fruit maturation. Based on the metabolome analysis, acetaldehyde and ethanol might be effective maturation indicators because these compounds changed more rapidly than sugars or organic acids. Thereafter, the physicochemical changes, including acetaldehyde and ethanol, were investigated during fruit development. The results showed that acetaldehyde and ethanol increased sharply from the ripe to overripening fruit, which could be used as the maturation indicators.
-
EFFECTS OF SALINITY ON GROWTH, PHYSIOLOGICAL AND BIOCHEMICAL RESPONSES OF TOMATO 査読あり 国際誌
Nasratullah Habibi, Naveedullah Sediqui, Naoki TERADA, Atsushi SANADA, and Kaihei KOSHIO
Journal of ISSAAS 27 ( 2 ) 14 - 28 2021年
記述言語：英語 掲載種別：研究論文（学術雑誌）
Salinity stress creates serious problems for tomato production in dry climate regions like Southeast Asia. Two sets of experiments were conducted, where the initial experiment was on effects of salinity on seed germination and seedling characteristics in the laboratory and the second experiment was to evaluate the effects of salinity on growth, physiological and biochemical responses of tomato. These experiments were carried out in the greenhouse of the Laboratory of Tropical Horticulture Science in Tokyo University of Agriculture during 2020 and 2021. Tomato (Solanum lycopersicum L. cv. Micro-Tom) was used as plant material and sodium chloride was used as salt. The experiment was designed in complete randomized design with 4 salt treatments (50, 100, 150, and 200 mM), and control (no sodium chloride). In the initial experiment, it was found that the germination rate, shoot and root length were significantly reduced under saline conditions. In the second experiment, the seeds were first grown in vermiculite, and 3-4 leaf seedlings were transplanted into a hydroponics system where the saline treatments were applied. It was observed that salinity, at the rates tested, decreased plant height, root length, the number of flowers, photosynthetic rate, transpiration rate, and stomatal conductance, but it increased leaf temperature. Moreover, sugars decreased under salinity, while organic acids, MDA and proline content increased. Proline and MDA are produced in response to salt stress. Accordingly, fruit yield was reduced under salinity as compared to control.
-
PHYSIOLOGICAL STUDY ON TOMATO FRUIT TO KEEP FRESHNESS UNDER HIGH-TEMPERATURE CONDITIONS 査読あり 国際誌
Gulbuddin GULAB, Mohammad Mustafa HARIS, Naoki TERADA, Atsushi SANADA, Hiroshi GEMMA, and Kaihei KOSHIO
Journal of ISSAAS 26 ( 1 ) 17 - 28 2020年
担当区分：責任著者 記述言語：英語 掲載種別：研究論文（学術雑誌）
This paper studied the possibility of high-temperature storage of green mature tomato fruit. First, green mature tomato fruit were stored at 25, 31, 33, 35, and 37 0C for 17 days and thereafter shifted to 25 0C to check the effect of storage temperature on fruit freshness before and after shifting to 25 0C. In another experiment, tomato fruit were harvested at green mature stage and stored at 33 0C for 0 (control), 5, 10, 20 and 30 days, thereafter shifted to 25 0C to investigate the effect of high-temperature storage on fruit freshness before and after shifting to 25 0C. This research was conducted at Tokyo University of Agriculture, Japan from 2017-2019. Fruit color development, weight loss, fruit firmness, ethylene production, CO2 release, Brix, sugars, organic acids, 1-amino cyclopropane-1-carboxylic acid (ACC) content, and ACC oxidase (ACO) activities were measured as freshness indices. The possibility of longer storage of green mature tomato fruit under high temperature was discussed, which might well contribute to facilitate the harvesting operation in the summer season in developing countries, like Southeast Asian countries.
-
GROWTH, QUALITY AND CAPSAICIN CONCENTRATION OF HOT PEPPER (CAPSICUM ANNUUM) UNDER DROUGHT CONDITIONS 査読あり 国際誌
Mohammad Mustafa HARIS , Trizhia Marie SILVA, Gulbuddin GULUB, Naoki TERADA, Takashi SHINOHARA, Atsushi SANADA, Hiroshi GEMMA and Kaihei KOSHIO
Journal of ISSAAS 26 ( 1 ) 100 - 110 2020年
担当区分：責任著者 記述言語：英語 掲載種別：研究論文（学術雑誌）
Drought stress is a major production constraint for fruits and vegetable crops in arid and semi-arid regions. This study was conducted to investigate the effect of drought stress on growth, quality and capsaicin concentration of hot pepper. The study was conducted from March 2017 to September 2018 in the greenhouse of Laboratory of Horticultural Science in Tokyo University of Agriculture (TUA). Germinated seeds were grown in a seed tray and were transplanted in plastic pots at 3 to 4-leaf stage. Drought stress treatments initiated after the first anthesis (26 days after transplanting) with moderate (7 days interval irrigation), severe (9 days interval irrigation) and control (daily watering). Results showed that capsaicinoids, sugars accumulation and ethylene production rate in response to drought stress increased significantly compare to daily irrigated. Fruits harvested at 36 and 45 days after anthesis accumulated higher concentration of glucose, fructose and sucrose in response to moderate and severe stress than daily irrigation. Whereas, capsaicin and dihydrocapsaicin content in fruits harvested at 36 and 45 DAA showed a significant increased under severe and moderate stress. The present findings revealed that drought stress will affect capsaicinoids, sugar and organic acid accumulation of hot pepper fruits and might alter the primary and secondary metabolites.
-
FRUIT GROWTH PATTERN IN DATE PALM (Phoenix dactylifera) ‘SUKKARY’ AND ‘KHLASS’ VARIETIES 査読あり 国際誌
Abdelazize ELJIATI, Anass ROUIFI, Trizhia Marie Bool SILVA, Naoki TERADA, Atsushi SANADA and Kaihei KOSHIO
Journal of ISSAAS 26 ( 2 ) 54 - 65 2020年
記述言語：英語 掲載種別：研究論文（学術雑誌）
The growth physiology of date palm (Phoenix dactylifera) ‘Sukkary’ and ‘Khlass’ was determined. This research sought to study the fruit growth pattern of these two varieties and to elucidate the different growth phases of the fruits to better manage thinning, water and nutrient supply of the crop. These were done using the following fruit parameters: weight, volume, length and width. When regressed against fruit weight, all other mentioned parameters had a high determination coefficient. The fruit patterns of bunch cut thinning method were compared with non-thinned fruits and surveyed for an alternative to hand thinning in order to improve fruit size. It was suggested that bunch cutting at the time of pollination and keeping of 12 fruits per spikelet are better alternatives to hand thinning. These alternative methods improved better fruit size in ‘Sukkary’ (17.4 g) compared to hand thinned fruits (16.2 g) and to non-thinned fruits (13.7g).
-
A Field Study on the Production, Trade and Post-Harvest Handling of Tomato Fruit in Eastern Afghanistan 査読あり
GULAB Gulbuddin, ABDIANI Saidajan Attiq, TERADA Naoki, SANADA Atsushi, GEMMA Hiroshi, KOSHIO Kaihei
Tropical Agriculture and Development 64 ( 1 ) 7 - 12 2020年
担当区分：責任著者 記述言語：英語 掲載種別：研究論文（学術雑誌） 出版者・発行元：Japanese Society for Tropical Agriculture
<p>In Afghanistan, urbanization, population increase, climate change, the application of chemical inputs, hybrid seeds, greenhouse and processing technologies, trade activities and other facilities have brought about great changes in production and the consumption rate of vegetables, especially in the case of tomato. A field survey on the production, trade and post-harvest handling of tomatoes was conducted in Eastern region of Afghanistan, using questionnaires. The interviewees were agricultural organizations, producers, traders, consumers and university professors. The objective of the survey was to evaluate the tomato production, trade, and the post-harvest handling process in the area, and it was found that the availability of quality inputs such as hybrid seeds and fertilizers had a great impact on the yield and quality of the fruit as well as the post-harvest technology on the prevention of fruit loss. According to the results, the SWOT (Strengths, Weaknesses, Opportunities, and Threats) matrix was summarized. Based on the findings, we hope to improve the pre-and post-harvesting activities in order to increase the income of stakeholders through better agriculture practices and a reduction of loss.</p>
DOI： 10.11248/jsta.64.7
-
Etyhlene evolution and premature drop in passion fruit (Passiflora edulis x P. edulis flavicarpa) 査読あり
Takashi SHINOHARA, Mizuki USUI, Ayaka SABANAI, Atsushi SANADA, Daizou IGARASHI, and Kaihei KOSHIO
Tropical Agriculture and Development 63 ( 3 ) 105 - 112 2019年09月
記述言語：英語 掲載種別：研究論文（学術雑誌）
-
エチオピア国中央部リフトバレー地域の火山灰土の熱伝導率と熱拡散係数が地温に及ぼす影響 査読あり
鈴木伸治・飯塚圭子・真田篤史・伊藤博武・渡邉文雄
沙漠研究 29 ( 3 ) 91 - 101 2019年
記述言語：英語 掲載種別：研究論文（学術雑誌）
エチオピア国のリフトバレー（地溝帯）周辺には，火山灰土が分布している．土地管理が不適切であったために， この地域は森林伐採とそれに続く土壌荒廃に見舞われている．そのためこの地域の土壌は強い日射にさらされるように なったが，地温環境についてはよく知られていなかった．火山灰土壌は一般の鉱物質土壌に比べ，特異的な物理性を示 すことから，筆者らは，エチオピアリフトバレーの火山灰土地帯も特徴的な温度環境を示すという仮説を立てた．本研 究の目的は，エチオピアリフトバレーの土壌の熱的性質（熱伝導率と熱拡散係数）を調べ，それらが地温に及ぼす影響 について検討することである．測定の結果，エチオピアリフトバレーの土壌は，固相の熱伝導率が低いこと，また間隙 率が多いことにより，非火山灰土に比べて低い熱伝導率を示し，そのため熱拡散係数も低い値を示すことが明らかになっ た．この性質は，日本の火山灰土の熱的性質に類似していた．このことからエチオピアリフトバレー地域の地温環境の 特徴として，強い日射のために地表面では温度が非常に高くなるものの，土壌の熱拡散係数が低いことによって熱が下 層まで伝わらず，下層では地温の日変動が非常に小さくなることが明らかになった．
-
Effect of 1-MCP on ethylene regulation and quality of tomato cv. Red Ore 査読あり 国際誌
Poyesh, D.S., Terada, N., Sanada, A., Gemma, H. and Koshio, K
International Food Research Journal 25 ( 3 ) 1001 - 1006 2018年06月
記述言語：英語 掲載種別：研究論文（学術雑誌）
1-MCP is a new tool for regulating ethylene and preserving the quality of fresh produce. Tomato fruit Solanum lycopersicum cv. Red Ore harvested at green and pink stages was used to examine the effect of 1-MCP on their ethylene production and quality. After treating with 1-MCP for 24 hours, ethylene, ACS, ACC, CO2, color, firmness and weight loss were measured. Differences in ethylene production at mature green and pink stages, might be due to the effect of 1-MCP on ethylene production through changed activity of ACS, result in blocking of autocatalysis (mature green) and autoinhibition (pink stage). The shelf lives were improved in 1-MCP-treated fruit at both stages of harvest as indicated by the decrease in respiration, softening, and weight loss, along with the delay in color change (a-value). Our results newly suggest that 1-MCP treatment can have different affects on tomato ethylene production depending on maturation stages (green or pink), but contribute to prolong the shelf life in both stages of tomato fruit.
-
Bulbil dormancy and formation in water yam (Dioscorea alata L.) 査読あり
Atsushi SANADA, Chuwen CHENG, Hidehiko KIKUNO and Hironobu SHIWACHI
Tropical Agriculture and Development 62 ( 3 ) 109 - 114 2018年05月
担当区分：筆頭著者, 責任著者 記述言語：英語 掲載種別：研究論文（学術雑誌）