著者
Ken-ichiro YASUBA Hidehito KUROSAKI Takehiko HOSHI Takashi OKAYASU Yoshiyuki TANAKA Tanjuro GOTO Yuichi YOSHIDA
出版者
Japanese Society of Agricultural, Biological and Environmental Engineers and Scientists
雑誌
Environmental Control in Biology (ISSN:1880554X)
巻号頁・発行日
vol.56, no.3, pp.107-112, 2018 (Released:2018-07-20)
参考文献数
17

A program library for use on open-source hardware was developed in order to construct a low-cost environmental control system for greenhouses. The library facilitated the development of environmental sensing and control devices that conform to the protocols of the Ubiquitous Environment Control System (UECS). The open-source hardware used was the "Arduino Ethernet" and the "Arduino Mega 2560 with Ethernet Shield" microcontroller boards. UECS is a system for controlling greenhouse environments that communicates information via a local area network, and devices utilizing the library that we developed can perform the UECS defined communication tasks automatically. With the help of this library, device developers no longer need to program the communications aspects of the device and can concentrate on programming setting and control logic of the device. The library occupies about 29 kilobytes of the read only memory area of the target board. The library and associated open-source microcontroller boards are powerful tools for developing low-cost environmental control systems.
著者
Tran Duy Vinh Yuichi Yoshida Mitsuo Ooyama Tanjuro Goto Ken-ichiro Yasuba Yoshiyuki Tanaka
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.OKD-114, (Released:2017-11-17)
被引用文献数
14

Blossom-end rot (BER) in tomato has been generally reported as a calcium (Ca)-related physiological disorder influenced by cultivar and environmental factors. In our previous works, we found that different fruit-sized cultivars could share a similar threshold value of water-soluble Ca. In addition, seasonal susceptibility to BER was closely related to fruit growth rate. This study aimed to clarify the effect of fruit growth rate as a dominant factor determining the susceptibility in different fruit-sized tomato cultivars. A large-sized cultivar, ‘Momotaro Fight’, and medium-sized ‘Cindy Sweet’, with different susceptibility to BER disorder, were hydroponically grown with modified Hoagland nutrient solutions consisting of a range of Ca:K (potassium) ratios in four cropping seasons. In spring and summer, BER incidence was more than 60 and 10% in ‘Momotaro Fight’ and ‘Cindy Sweet’, respectively, when plants were fed with low Ca. BER was rarely observed when water-soluble Ca exceeded 0.30 μmol·g−1 FW, and the rate of BER incidence increased with a decrease in water-soluble Ca concentration in both cultivars. Fruit growth rate was much more vigorous in ‘Momotaro Fight’ than ‘Cindy Sweet’, especially in summer. It was significantly favored by the increased temperature and solar radiation in both cultivars. The multiple regression analyses detected a significant effect of fruit growth rate on BER incidence, exclusively in ‘Momotaro Fight’. Together with water-soluble Ca, fruit growth rate explained over 50% of the variation of BER incidence. A vigorous rate of fruit growth can play a more important role in decreasing water-soluble Ca in ‘Momotaro Fight’, and result in severe and frequent BER incidence, compared to ‘Cindy Sweet’. Thus the cultivar difference in the susceptibility to BER is likely explained by the difference in the growth rate of young fruit affecting water-soluble Ca in the distal part of tomato fruit.
著者
Erasmus Kirii Tanjuro Goto Yuichi Yoshida Ken-ichiro Yasuba Yoshiyuki Tanaka
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.MI-148, (Released:2016-05-27)
被引用文献数
1 20

Pungency in peppers is due to the presence of the alkaloid capsaicin and its analogues, collectively known as capsaicinoids. These compounds are only produced in the Capsicum genus and function as deterrents to mammals from consuming the pepper fruits. Pungency in pepper is qualitatively controlled by the Pun1 locus, which encodes a putative acyltransferase enzyme. Mutations in the Pun1 gene result in a loss of pungency, and several Pun1 loss-of-function alleles have been identified in sweet peppers to date (pun11–3). However, variations in pun1 alleles have not been completely elucidated. In the present study, we report a new type of loss-of-function pun1 allele, named pun14, in a Japanese sweet pepper cultivar, ‘Nara Murasaki’ (C. annuum). Sequence analysis at the Pun1 locus revealed that this type of Pun1 allele is caused by a single adenine nucleotide insertion in the second exon region. This insertion is unique to ‘Nara Murasaki’ and is not present in wild-type Pun1. This insertion causes a frameshift mutation and a change in the amino acid sequence, resulting in a truncated protein. The results of gene expression analysis indicated that the expression of Pun1 in ‘Nara Murasaki’ was hardly detectable, while the transcripts of this gene were strongly expressed in a pungent cultivar. In a co-segregation test, the pun14 genotype perfectly co-segregated with non-pungency in 103 F2 population plants of a cross between ‘Nara Murasaki’ and a pungent cultivar. ‘Nara Murasaki’ and a DNA marker to distinguish the pun14 allele will be informative for understanding the domestication process of sweet peppers.
著者
Tadahisa Higashide Ken-ichiro Yasuba Takeshi Kuroyanagi Akimasa Nakano
出版者
一般社団法人 園芸学会
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.MI-010, (Released:2015-02-21)
被引用文献数
3 24

To investigate the mechanism of yield increase by elevated carbon dioxide (CO2) and fogging in Japanese tomato cultivars (Solanum lycopersicum), total above-ground dry matter (TDM), fraction of dry matter distribution to fruit (FDF), and photosynthetic characteristics were measured in 3 Japanese cultivars grown in elevated CO2 with fogging and ambient CO2 without fogging. Fresh fruit yield and TDM were improved by the elevated CO2 and fogging in the 3 Japanese cultivars. Light use efficiency (LUE) was also increased by the elevated CO2 and fogging. No significant decrease in FDF was observed by the elevated CO2 and fogging in 2 Japanese cultivars, ‘Asabiyori 10’ and ‘Junkei Aichi Fast’. Thus, the increase in TDM by higher LUE contributed directly to the yield increase in these 2 cultivars. However, FDF in ‘Momotaro York’ was decreased significantly by the elevated CO2 and fogging. Thereby, the yield increase by the elevated CO2 and fogging was diminished in ‘Momotaro York’ in spite of the increase in TDM. The number of trusses having immature fruit in ‘Momotaro York’ under elevated CO2 and fogging was significantly higher than those of the others, although no increase in the number of trusses having immature fruit was observed in the other 2 cultivars. Although vegetative growth characteristics such as leaf area, LAI, and fresh and dry weights of leaves and stem were increased by the elevated CO2 and fogging, no negative effects such as a change in light-extinction coefficient and a decrease in maximum photosynthetic rate were observed. The elevated CO2 and fogging increased the number of harvested fruit but decreased weight per fruit, namely, fruit size, in the 3 cultivars.
著者
Yuichi Yoshida Nobuyuki Irie Tran Duy Vinh Mitsuo Ooyama Yoshiyuki Tanaka Ken-ichiro Yasuba Tanjuro Goto
出版者
園芸学会
雑誌
Journal of the Japanese Society for Horticultural Science (ISSN:18823351)
巻号頁・発行日
pp.CH-107, (Released:2014-07-04)
被引用文献数
2 14

To understand the factors affecting the incidence of blossom-end rot (BER), the effect of the Ca/K ratio (4/12–12/4, in me·L–1) in nutrient solutions and Ca concentration in fractions in the distal part of young tomato fruits immediately before BER symptoms appear were investigated for three seasons. The rate of BER incidence increased with a decrease in the Ca/K ratio in the supplied solutions in the summer and spring, but little difference was observed in the winter. Ca concentration was highest in winter and lowest in summer, and the concentration in fractions decreased with a decrease in the Ca/K ratio of the solutions. When the results of all three experiments were pooled, among the fractions, water-soluble Ca concentration was found to have the highest significance in the relationship to BER incidence. The risk of BER incidence in rapidly growing tomato increased to a critical level when water-soluble Ca in the distal part of the fresh fruit decreased to less than 0.20 μmol·g–1 FW. Multiple-regression analysis revealed that the concentration of water-soluble Ca, which is predominantly recovering apoplastic or cytoplasmic Ca2+, and total Ca, which has been translocated during fruit development, are significantly affected by solar radiation and Ca concentration in the supplied solution rather than air temperature.
著者
Tadahisa Higashide Akimasa Nakano Ken-ichiro Yasuba
出版者
園芸学会
雑誌
Journal of the Japanese Society for Horticultural Science (ISSN:18823351)
巻号頁・発行日
pp.CH-048, (Released:2014-05-09)
被引用文献数
2 19

To improve the yield of a Japanese tomato (Solanum lycopersicum) cultivar and determine how fruit yield changes as a result of grafting, we investigated the effects of a Dutch rootstock [‘Maxifort’ (S. lycopersicum × S. habrochaites): Mx] on the dry matter (DM) production and fruit yield of Dutch and Japanese cultivars. The Japanese cultivar (‘Momotaro York’: My) grafted onto Mx (My/Mx: scion/rootstock) had significantly higher fresh and dry weights of fruits per unit area than My/My. Fruit fresh weight yield per unit area was highly correlated with fruit dry weight (DW) yield (r = 0.96–0.97, P < 0.001), and DW yield was significantly correlated with total aboveground DM (r = 0.71–0.96, P < 0.001) and with DM allocation to the fruits (r = 0.52–0.75, P < 0.01). Total aboveground DM (TDM) was significantly and highly correlated with light-use efficiency (r = 0.98, P < 0.001). However, there was no significant correlation between light-use efficiency and the maximum photosynthetic rate, stomatal conductance, or the light-extinction coefficient. Although stomatal conductance significantly (P < 0.05) differed between the rootstocks at 57 and 119 days after transplanting (DAT), there was no significant difference in the maximum photosynthetic rate between the scion/rootstock combinations at 57 and 119 DAT. These results indicated that the fruit yield of My could be improved by grafting onto Mx, and that the increases in yield and TDM were mainly determined by the increase in light-use efficiency.