著者

Haruna Yada Chihiro Matsumoto Xiaonan Xie Kazuhisa Kato Hiroki Ikeda

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-356, (Released:2022-03-16)

---

Fruit mass is an important factor for determining the yield of tomatoes (Solanum lycopersicum), with higher mass being an important objective. Most fruit traits, including fruit mass, are quantitative, and numerous quantitative trait loci (QTL) control these traits. Previous studies investigating tomato introgression lines (ILs) revealed several QTLs for fruit yield, and suggested that IL12-1 is a potential line to increase fruit mass. Our aim was to facilitate genetic studies of the diverse characteristics of wild relatives of tomato. Therefore, tomato ILs from a cross between Solanum pennellii and the cultivar S. lycopersicum ‘M82’ were used. ILs that carry a S. pennellii chromosome segment on chromosome 12 of ‘M82’ were evaluated further for fruit mass expansion and regulation. IL12-1-1, a subline of IL12-1, was found to produce large ripening fruits compared with ‘M82’, a phenotype that resulted in increased pericarp thicknesses. To investigate the physiological mechanisms contributing to the increased fruit mass of IL12-1-1, the cell counts of fruit pericarp tissues during fruit development were evaluated. Cell numbers of IL12-1-1 fruit pericarp at 20 days after flowering were higher than those of ‘M82’, a difference that most likely occurred during the cell division phase. In addition, the levels of the phytohormones auxin and cytokinin, which are known to be related to cell division of the fruit tissue, were higher in IL12-1-1 compared with ‘M82’. Therefore, differences in these phytohormones between ‘M82’ and IL12-1-1 may be affected by the number of cells in the pericarp tissues. Expression analysis of Solyc12g005250 (SlKLP) and Solyc12g005310 (SlGH3-15), which are located in the IL12-1-1 region of the S. pennellii chromosome, showed significant differences between ‘M82’ and IL12-1-1 during the cell division phase; a better understanding of IL12-1-1 cellular and molecular features can contribute to the breeding and increased production of tomato crops.

著者

Shuhei IZAWA Nanako NAKAMURA-TAIRA Chihiro MORIISHI Toru YOSHIKAWA Rie AKAMATSU Hiroki IKEDA Tomohide KUBO

出版者

National Institute of Occupational Safety and Health

雑誌

Industrial Health (ISSN:00198366)

巻号頁・発行日

pp.2023-0068, (Released:2023-09-15)

---

Mental health problems are prevalent among the working population and must be resolved. We conducted a web-based large-scale study of workers, including a baseline survey and two follow-up surveys, to investigate the associations between self-care behaviors in daily life (e.g., stress coping, sleep, diet, and exercise), work environment improvements, and mental health among Japanese employees from various industries. In this protocol, we demonstrate the study design and demographic data of the participants in the baseline survey. Invitations to participate in this study were sent to 421,825 internet monitor registrants in February 2022. Overall, 20,000 registrants who met the inclusion criteria participated in the survey. There were large variations in occupations and working styles (e.g., physical work, night work, and teleworking) among the participants, and we also found significant differences between male and female participants in the demographic data. An overview of the survey data suggests that the demographic characteristics of the participants in this study are comparable to those reported in previous studies on Japanese employees. We plan to use these survey data in the future to examine the associations of daily lifestyles and work environments with the mental health of Japanese employees.

著者

Takaya Ishii Miki Suto Natsuki Suzuki Hiroki Ikeda

出版者

The Japanese Society for Horticultural Science

雑誌

The Horticulture Journal (ISSN:21890102)

巻号頁・発行日

pp.UTD-343, (Released:2022-07-14)

---

Onion (Allium cepa L.) is one of the most important vegetable crops in the world, and its cultivation is roughly divided into two types: autumn- (overwinter) and spring-sowing. In this study, we compared the changes in plant growth and bulb development of four short-day and intermediate-day onion cultivars under two years of varying environmental conditions to understand autumn-sowing cultivation and growth characteristics. A comparison of the growth parameters of the four cultivars throughout the growth period revealed that the increase in total leaf number and area, and plant height were almost completely inhibited in winter. In spring, these growth parameters increased rapidly in the early maturing cultivars and reached a plateau depending on the cultivar’s maturity type, as previously shown in spring-sowing cultivation. It is known that AcFT1 and AcFT4 play a key role in the bulb development of cultivated onions. Therefore, we conducted expression analysis of these genes for the four cultivars grown in the field and confirmed that AcFT1 was expressed following the maturity, irrespective of cultivation methods. We also analyzed AcGI expression in leaf blades, and a certain relationship between changes in bulb development and AcGI expression was observed. Correlation analysis of AcFT1 expression and total leaf number and area was conducted, and strong positive correlations were observed. In conclusion, our study demonstrated genetically that leaf number and area are important for inducing onion bulb development.

著者

Hiroki Ikeda Tomoki Shibuya Manabu Nishiyama Yoshihiro Nakata Yoshinori Kanayama

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-015, (Released:2016-09-28)

被引用文献数

21

---

Calcium (Ca2+) concentration, early fruit growth, and expression of Ca2+-movement-related genes were analyzed during early fruit development in the tomato, which is the most important stage regarding the incidence of blossom-end rot (BER), to investigate the physiological mechanisms affecting the occurrence of BER. We used tomato introgression line IL8-3 with a chromosome segment from a wild relative (Solanum pennellii) because this line shows lower incidence of BER compared with the parent cultivar ‘M82’ (S. lycopersicum), as described previously. Ca2+ concentration in fruit and leaves was higher in IL8-3 than in ‘M82’, whereas no significant differences were observed between Ca2+ concentration in roots and stems of ‘M82’ and IL8-3. These results suggested that a Ca2+ transport property is an essential factor for the lower incidence of BER in IL8-3. IL8-3 fruit showed a lower growth rate than ‘M82’, which could result in preventing the occurrence of BER. The expression of genes encoding cation exchangers, Ca2+-ATPases, a Ca2+ channel, and Na+/Ca2+ exchangers, was higher in IL8-3 fruit than in ‘M82’ fruit, suggesting active Ca2+ movement in IL8-3. All results in this study could be related to physiological mechanisms accounting for the lower incidence of BER in IL8-3.

著者

Hiroko NAKAZAWA Hiroki IKEDA Toshio YAMASHITA Ichiro HARA Yuko KUMAI Ginji ENDO Yoko ENDO

出版者

National Institute of Occupational Safety and Health

雑誌

Industrial Health (ISSN:00198366)

巻号頁・発行日

vol.43, no.2, pp.341-345, 2005 (Released:2006-03-17)

参考文献数

19

被引用文献数

17 32

---

The adverse health effects caused by indoor air pollution are termed “sick building syndrome”. We report such a patient whose symptoms appeared in the workplace. A 36-year-old female office worker developed nausea and headache during working hours in a refurbished office. After eight months of seeking help at other clinics or hospitals without improvement, she was referred to our hospital. At that time she reacted to the smells of various chemicals outside of the office building. Biochemical findings were all within normal ranges. Specific IgE antibody to cedar pollen was positive and the ratio of TH1/TH2 was 4.5. In the Eye Tracking Test (ETT), vertical eye movement was saccadic. Her anxiety level was very high according to the State-Trait Anxiety Inventory (STAI) questionnaire. Subjective symptoms, ETT findings and anxiety levels on STAI gradually improved during two years of follow-up. One year after the onset of her illness, the formaldehyde concentrations in the building air ranged from 0.017-0.053 ppm. Even though relatively low, chemical exposure from building materials such as formaldehyde induced a range of symptoms. Also, lack of recognition by superiors and doctors that sick building syndrome might have been the source of her illness coupled with her high state of anxiety may have exacerbated her symptoms and led to the onset of multiple chemical sensitivity. Thus psychosocial factors may contribute to sick building syndrome in the workplace.