著者
Yuya Mochizuki Tiejun Zhao Wataru Kanematsu Takashi Kawasaki Takeshi Saito Akio Ohyama Akimasa Nakano Tadahisa Higashide
出版者
The Japanese Society for Horticultural Science
雑誌
The Horticulture Journal (ISSN:21890102)
巻号頁・発行日
pp.UTD-055, (Released:2019-04-11)
被引用文献数
4

To clarify the effect of ultrafine bubbles (UFBs) on the growth of tomato seedlings, we investigated elongation growth and dry matter production by analysing growth under different assimilation conditions and by modelling. The leaf area enlargement rate of plants grown with UFB nutrient solution increased and the specific leaf area (SLA) decreased at 18 days after sowing (DAS) relative to those grown without UFB solution. Thus, UFBs increased both leaf area and leaf thickness. UFB significantly increased the relative growth rate (RGR) and net assimilation rate (NAR) at 18 DAS, but there was no significant difference in SLA, RGR, and NAR between treatments at 25 DAS. These results were used to model plant growth with and without UFB treatment. In a second experiment, UFB treatment increased aboveground dry weight under a low-assimilation condition, but had no significant effect under a high-assimilation condition. Our model supported these results. It was also implied that UFB treatment affected leaf area expansion, but not dry matter production. Although the values predicted by the model were slightly lower than observed, it was possible to predict the effect of UFB treatment on plant growth with high accuracy.
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
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.