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Murakami S.,Shizuoka Research Institute of Agriculture and Forestry | Ikoma Y.,Japan National Agriculture and Food Research Organization | Yano M.,Japan National Agriculture and Food Research Organization
Environmental Control in Biology | Year: 2015

We present a detailed study of differences in the fruit ripening stage on the vines and ethylene treatment in the red kiwifruit cultivar 'Rainbow Red' (Actinidia chinensis). We evaluated the fruit quality (core and flesh firmness, soluble solid content (SSC), and titratable acid (TA)); ethylene metabolism; and gene expression of ACS1, ACO3, EIL4, ERF14, and PGB at each stage. Fruits on the vines somewhat softened gradually. SSC increased, and core and flesh firmness as well as TA decreased gradually. However, rapid ethylene production was not observed, and gene expression of ACS1, ACO3, EIL4, ERF14, and PGB was at the basal level at each stage. While the fruit quality following ethylene conditioning, core and flesh firmness, and TA rapidly decreased, SSC and ethylene production rapidly increased. It was confirmed that gene expression of ACS1, ACO3, EIL4, ERF14, and PGB rapidly increased. These results suggested that the ripening of 'Rainbow Red' on the vines is not associated with ethylene.


Murakami S.,Shizuoka Research Institute of Agriculture and Forestry | Ikoma Y.,Japan National Agriculture and Food Research Organization | Yano M.,Japan National Agriculture and Food Research Organization
Journal of the Japanese Society for Horticultural Science | Year: 2014

Premature softening during low-temperature storage is a major issue in the red kiwifruit (Actinidia chinensis Planch.) cultivar 'Rainbow Red'. The objective of this study was to investigate the effect of low temperature on ethylene sensitivity in this cultivar. We demonstrate how ethylene preconditioning at 4°C and 25°C interacted with more rapidly ripening at the lower temperature in 'Rainbow Red' kiwifruit. The expression of ripening-related genes ACS1, ACO3, EIL4, ERF14, and PGB was at the basal level during ethylene preconditioning at 4°C and 25°C, and rapidly increased with ethylene treatment following ripening. These results suggest that low-temperature storage enhances ethylene sensitivity in 'Rainbow Red'. © 2014 The Japanese Society for Horticultural Science (JSHS), All rights reserved.


Kondo T.,Saitama City Institute of Health Science and Research | Watanabe A.,Saitama City Institute of Health Science and Research | Shitara H.,Saitama City Institute of Health Science and Research | Kaburagi Y.,Saitama City Institute of Health Science and Research | And 12 more authors.
Journal of the Food Hygienic Society of Japan | Year: 2013

The effects of processing to produce various types of tea or infusion on the levels of pesticide residues in tea were investigated for three insecticides (chlorfenapyr, pyrimiphos-methyl, and clo-thianidin). Tea plants were sprayed with one of the three pesticides and cultivated under cover. The levels of pesticide residues in tea decreased after processing according to the time and temperature of heating, as well as fermentation. Although significant differences were not observed among the three pesticides in the ratio of decreased of pesticide concentration after processing to green tea, clothianidin, which is a neonicotinoid insecticide and has a lower log P ow value, tended to be transferred more than the other two insecticides into infusions. However, no significant difference in the ratios of clothianidin transferred to infusions was observed among green tea with three different leaf sizes.


Yamamoto S.,Meiji University | Yamagiwa Y.,Shizuoka Research Institute of Agriculture and Forestry | Inaba Z.,Shizuoka Research Institute of Agriculture and Forestry | Handa T.,Meiji University
Acta Horticulturae | Year: 2014

Lilium japonicum and L. auratum are endemic Japanese lilies, and have been used for parents in breeding of oriental hybrid lilies. L. japonicum has pink or white coloured funnel like flowers without spots, and is distributed mainly in the western part of Japan which includes Honshu (main island), Shikoku (west island) and Kyushu (south-west island). L. auratum has larger flowers with white tepals, yellow stripes and red spots, and is distributed on the eastern side of Honshu in Japan. The natural hybridization of these two species occurs only at the edge of their distribution which is on the South of Izu peninsula of Honshu main island. It is suggested that putative hybrids can be classified into three types by their morphological characters; L. japonicum type, intermediate type and L. auratum type, however their genetic structure has not been revealed yet. In this study, six wild populations of these lilies were investigated by morphological and genetic analysis. Principal component analysis by using ten morphological characters revealed large morphological diversity within putative hybrids. Five SSR markers are used for microsatellite analysis, and a Bayesian clustering approach was implemented by Structure analysis. In the Bayesian clustering L. japonicum was assigned to cluster I and L. auratum was assigned to cluster II. Putative hybrids were assigned to cluster I and II. These results indicate that putative hybrid populations consist of introgressed mixture between two species.


Uchiyama T.,Shizuoka Research Institute of Agriculture and Forestry | Ozawa A.,Shizuoka Research Institute of Agriculture and Forestry | Yoo J.,Jangwon Industry Co.
Japanese Journal of Applied Entomology and Zoology | Year: 2013

We investigated susceptibility to 15 insecticides in populations of the smaller tea tortrix, Adoxophyes honmai Yasuda, collected from tea fields in the Makinohara area of Shizuoka Prefecture. In the Shimada-Yui population, the corrected mortality 10 days after treatment with each of three insect growth regulator (IGR) insecticides, tebufenozide, methoxyfenozide, and chromafenozide [diacylhydrazine (DAH) analogs], was lower in 2005 than in 2004. In the case of treatment with lufenuron and flufenoxuron [both benzoylurea (BU) analog IGRs], no clear difference in mortality was observed between 2004 and 2005. In the A. honmai populations examined, seven insecticides-chlorpyrifos, profenofos, chlorfenapyr, methomyl, spinosad, emamectin benzoate, and bifenthrin- showed higher insecticidal effects than the IGRs tested. In addition, the susceptibility of the Shimada-Yui population to DAH and BU IGRs was continuously investigated for 5 years. The LC50 values of the DAH analog tebufenozide showed a rapid annual increase after the start of investigations in 2004, and in 2008 far exceeded the registration dose of 200 ppm. The LC50 values of the DAH analog chromafenozide rose sharply from 2004 to 2005, and in 2005 generally exceeded the registration dose of 50-100 ppm. In contrast, although the LC50 values of the DAH analog methoxyfenozide began to rise after 2004, they still remained below the registration dose of 25-50 ppm in 2008. Increases in the LC50 values of the two BU analog IGRs, lufenuron and flufenoxuron, tended to be smaller compared with those of the three DAH analog IGRs. In the Shimada-Yui population, the resistance ratio of four IGRs-tebufenozide, chromafenozide, methoxyfenozide and lufenuron-showed an exponential upward tendency over the 5 years of the investigation. When resistance ratio values were log transformed, significant positive correlations (p<0.05) were observed between the resistance ratios and elapsed years. The slopes of the regression lines obtained for tebufenozide, methoxyfenozide, lufenuron, were 0.36, 0.17, and 0.14, respectively. Furthermore, on the basis of the slopes of the regression lines, it is estimated that there were 2.3-, 1.5-, and 1.4-fold increases in the resistance of A. honmai to tebufenozide, methoxyfenozide, and lufenuron, respectively.


Tsuchida Y.,Shizuoka Research Institute of Agriculture and Forestry | Masui S.,Shizuoka Research Institute of Agriculture and Forestry | Katai Y.,Shizuoka Research Institute of Agriculture and Forestry
Japanese Journal of Applied Entomology and Zoology | Year: 2013

We examined the effect of agrichemicals on an important predator, Geocoris proteus Distant, which has been observed in Allium crop fields. Adults and 3rd instar nymphs of G. proteus were dipped in 67 pesticide solutions at a practical concentration. As a result, two of ten organophosphorus insecticides, one of four carbamate insecticides, two of six neonicotinoid insecticides, two of six insect growth regulators (IGRs), nine of eleven other synthetic insecticides, all microbial insecticides, all acaricides and all fungicides were determined to be harmless (<30% mortality) to adults and 3rd instar nymphs of G. proteus. The use of these pesticides should be recommended by integrated pest management (IPM) programs to control Allium insect pests, since they are regarded as being compatible with the conservation of G. proteus in the field.


Uchiyama T.,Shizuoka Research Institute of Agriculture and Forestry | Ozawa A.,Shizuoka Research Institute of Agriculture and Forestry
Japanese Journal of Applied Entomology and Zoology | Year: 2015

We investigated the inheritance of tebufenozide resistance in the smaller tea tortrix, Adoxophyes honmai Yasuda, by crossing experiments using resistant (R) and susceptible (S) strains of Shizuoka Prefecture. The lethal concentration 50 values (ppm) of tebufenozide in the R and S strains were 595 and 4.46, respectively. The results of the F1 and F1' strains suggested that resistance to tebufenozide was inherited as an autosomal and incompletely dominanttrait. Furhermore, the results of F2, F2', and backcross strains showed that the resistance was controlled by polygenic factors.


Uchiyama T.,Shizuoka Research Institute of Agriculture and Forestry | Ozawa A.,Shizuoka Research Institute of Agriculture and Forestry
Applied Entomology and Zoology | Year: 2014

We investigated the susceptibility of the smaller tea tortrix, Adoxophyes honmai Yasuda, to diamide insecticides in the Shimada-Yui tea fields in Shizuoka Prefecture, Japan, from 2006 to 2011. By 2011, the insects had developed significant resistance even to concentrations far above the registration concentrations of two diamides, flubendiamide and chlorantraniliprole. The lethal concentration 50 (LC50) values of flubendiamide showed a rapid annual increase from 16.2 ppm in 2007 to 161 ppm in August 2011, exceeding the registration concentration of 100 ppm in 2010 and 2011. The LC50 values of chlorantraniliprole increased sharply from 25.3 ppm in 2010 to 98.8 ppm in August 2011, exceeding the registration concentration of 50 ppm. The LC50 values for flubendiamide and chlorantraniliprole at 10 days after treatment in insects collected in August 2011 were 105-fold and 77.2-fold higher, respectively, than those in a susceptible strain. © 2014, The Japanese Society of Applied Entomology and Zoology.


Takahashi T.,Shizuoka Research Institute of Agriculture and Forestry | Inagaki H.,Shizuoka Research Institute of Agriculture and Forestry | Fukushima T.,Shizuoka Research Institute of Agriculture and Forestry | Oishi T.,Shizuoka Research Institute of Agriculture and Forestry | Matsuno K.,Shizuoka Research Institute of Agriculture and Forestry
Soil Science and Plant Nutrition | Year: 2010

Denitrification of paddy fields is a key process for improving water quality in fields where nitrate concentrations are high. The objective of the present study was to understand the effects of incorporating organic carbon (C) into soil on the denitrification rate of paddy fields in winter. On 11 December 2007, separate paddy field plots were prepared by incorporating 5 Mg ha-1 of rice straw (RS), 11 Mg ha-1 of rice straw compost (RSC) or a control. A field with a high concentration of nitrate in the water (averaging 18 mg N L-1) was irrigated until 29 March. During the experiment, the daily average soil temperature at a depth of 0.05 m ranged between 3 and 15°C. The nitrate concentration in the surface water in the RS plot, where the residence time was 2 days, decreased more than the concentration in the control or RSC plots. The total estimated nitrate removal from each plot in relation to the other plots was RS > RSC = control. Measurements of the soil from each plot on 29 February 2008 showed that incorporation of RS significantly increased the denitrification potential, even at low temperatures (5-10°C). Furthermore, the RS plot contained more dissolved organic C than the control or RSC plots. This result indicates that supplying RS effectively increases denitrification under low-temperature conditions. © 2010 Japanese Society of Soil Science and Plant Nutrition.

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