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Volume 37 (1992)
- Issue 4 Pages 267-
- Issue 3 Pages 195-
- Issue 2 Pages 83-
- Issue 1 Pages 1-
- Issue SupplI Pages 2-
Volume 37, Issue 3
Displaying 1-11 of 11 articles from this issue
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Kunihiko Suzuki1992 Volume 37 Issue 3 Pages 195-203
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSDownload PDF (906K) -
Tatsuya Inamura1992 Volume 37 Issue 3 Pages 204-212
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSTuber formation under the control of aerial parts by the application of herbicides was analyzed in relation to the formation and elongation of rhizomes in the water chestnut, Eleocharis kuroguwai Ohwi. The accuracy of the control index, which is the ratio of the product of the number of hills and length of the weed plant in herbicide-treated plots to that in the untreated control plot, was confirmed in relation to the control of propagation. The results are as follows;
1. The regularity of stem development appeared to correspond to a three-whorl phyllotaxis (Fig. 1). The rate of rhizome formation on the stem, which is the ratio of the number of stems forming rhizomes to the number of hills, was affected by the regularity of stem development. The rate of rhizome formation on the weed stems in the inner of the hill was higher, while lower on those in the outer part of the hill (Fig. 2).
2. The rate of tuber formation on the stem, which is the ratio of the number of stems forming rhizomes and tubers to the number of hills, decreased by the inhibition of the stem elongation (Table 2). The length of the rhizomes, which distributed new tubers in the soil layers, decreased by the inhibition of the elongation of the stem (Table 3). The diameter of the new tubers and the weight of each tuber were larger, when the rhizome was longer in the deep soil layers (Table 4).
3. The specific gravity of lately formed tubers which were distributed in the shallow soil layers increased as the time of the tuber formation stage advanced, while that of the tubers in the deep layers of herbicide-treated plots decreased (Fig. 4).
4. The decrease of the specific gravity, which affected the sprouting of tubers, was ascribed to both the delay in tuber formation and reduction of assimilate by the inhibition of the growth of the stem length and diameter at the joint.
5. As mentioned previously, the control index, which was correlated with parameters such as formation, survivorship and sprouting of the tubers in the soil layers, was a suitable criterion of herbicidal activity.View full abstractDownload PDF (1009K) -
Yoko Sato1992 Volume 37 Issue 3 Pages 213-219
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSDegradation of trifluralin by soil bacteria was investigated.
1) Four bacterial strains were isolated from farmland soil treated with trifluralin and their degradation of this substance was evaluated. T-a and T-b strains exhibited weak and remarkable ability to degrade, respectively.
2) These strains were inoculated to a liquid medium and the remaining trifluralin in the broth was determined by gas chromatography (GC) using time intervals. The ratio of trifluralin degraded by T-a and T-b strains was about 20% and 95% after 28 days incubation, respectively.
3) GC-mass spectrometer (GC-MS) analysis of these metabolites revealed six compounds: α, α, α-trifluoro-5-nitro-N4, N4-dipropyltoluene-3, 4-diamine; α, α, α-trifluoro-N4, N4-dipropyltoluene-3, 4, 5-triamine; 2-ethyl-7-nitro-1-propyl-5-(trifluoromethyl)-benzimidazole; 7-amino-2-ethyl-1-propyl-5-(trifluoromethyl)-benzimidazole; α, α, α-trifluoro-5-nitro-N4-propyltoluene-3, 4-diamine and 3, 5-dinitro-4-(propylamino)-benzoic acid.
4) Investigation of the main bacteriological properties identified T-a and T-b strains as Alcaligenes sp. and Moraxella sp., respectively.View full abstractDownload PDF (636K) -
Yoshifumi Takaesu, Kazuko Takaesu1992 Volume 37 Issue 3 Pages 220-225
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThis study was carried out to investigate the incidence and characteristics of naturalized weed species based on vegetation analysis in fields of the main three crops cultivated in Okinawa Prefecture, i. e. sugarcane, pineapple, and vegetables.
1) In the fields of these main three crops there were 60 weed species belonging to 21 families. The largest number of naturalized weed species belonged to the Compositae and they occurred in all the fields, in particular in pineapple fields, followed by Gramineous weeds which were abundant in both sugarcane and pineapple fields, but few in vegetable fields.
2) The naturalized weeds in the sugarcane and pineapple fields, originated mainly from tropical America, while in the vegetable fields they originated mainly from Europe.
3) The ratio of naturalized weeds calculated from data based in the number of weeds appearing with the highest frequency as well as of dominant weeds was higher than that calculated from the total number of weed species observed. Therefore the naturalized species of weeds were chiefly responsible for the heavy damage causedto crops.
4) In the fields of the main three crops, the life form spectrum of Th, Th (w), R5, D1, D2, b among the naturalized weeds, was broader than that of the native ones. Since the ratio of naturalized weed was the highest in the vegetable fields, the life form spectrum of the weeds was affected by that of the naturalized weeds in these fields.View full abstractDownload PDF (631K) -
Keiko Nakatani, Katsuyoshi Noguchi, Tokuichi Kusanagi1992 Volume 37 Issue 3 Pages 226-231
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe effects of photoperiod and temperature during the growing period of mother plants on seed dormancy and germination were investigated in Persicaria vulgaris Webb et Moq..
The seeds for this experiment were harvested 10, 20 and 30 days after flowering, then they were stored at 22°C under dry conditions and at 5°C under wet conditions. Germination tests were carried out at the time of harvest and sequentially during the storage period.
The 1000 seed weight was heavier in the seeds produced under 8 hour day-length conditions compared with the seeds produced under 16 hour day-length conditions. The germination percentage of the former seeds was higher than that of the latter seeds after one month of storage at 5°C under wet conditions. The latter seeds exhibited a stronger light requirement for germination than the former seeds.
The 1, 000 seed weight was heavier in the seeds grown under low temperature (20°C) conditions compared with those grown under high temperature conditions. The germination percentage of the former seeds was higher than that of the latter after one month of storage at 5°C under wet conditions.
It was evident that the dormancy of the seeds produced by the plants grown under short daylength or low temperature conditions could be broken easily.View full abstractDownload PDF (711K) -
Kobkiat Sengnil, Kenji Usui, Kozo Ishizuka1992 Volume 37 Issue 3 Pages 232-238
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSCells tolerant to bensulfuron methyl (BSM) were isolated from a cell suspension culture of Oryza sativa L. cv. Nipponbare by a stepwise selection. Tolerant cells at 10-6 and 10-5M BSM, concentrations which severely inhibited normal cell growth, were selected after culturing in the herbicide-containing medium for 6 and 10 months, respectively, and tested for their tolerance to the herbicide. The tolerant cells showed stable high (>100-fold) tolerance to BSM. The target enzyme, acetolactate synthase (ALS) extracted from both normal and tolerant cells was inhibited by BSM in a concentration-dependent manner. The increase in level of ALS activity with less sensitivity to BSM of the tolerant cells occurred during culture and even after their selection. The extractable enzyme activities were 91% and 48% of untreated normal cells in 10-6M and 10-5M BSM-tolerant cells, respectively. Despite the lower level of extractable ALS activity from tolerant cells, this activity was relatively less sensitive to BSM than that from normal cells. These results suggest that the acquisition of tolerance resulted, at least in part, from the production of ALS with reduced sensitivity to inhibition by the herbicide.View full abstractDownload PDF (733K) -
Tsugio Ezaki, Masafumi Fujihisa, Yoshihiko Imon1992 Volume 37 Issue 3 Pages 239-247
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe purpose of this study was to investigate, mainly from the viewpoint of disaster prevention, the utilization of Zoysia japonica Steud., Cynodon dactylon Pers.×Cynodon transvaalensis Burtt-Davy (Tifton 328), Imperata cylindrica Beauv., Miscanthus sinensis Anderss., Shibataea kumasaca Nakai, Hedera canariensis Willd., Sasaella kogasensis Nakai var. gracillima S. Suzuki and Sasa palmata Nakai var. niijimai S. Suzuki on slopes of river banks and roads.
The authors determined the amount of standing crop, as well as the physical and chemical properties of the soil in the fields where these plants grows.
Shibataea kumasaca Nakai exhibited the longest value for the standing crop among the eight species. The weight of the above-ground parts was 4, 322g/m2 and that of the roots was 4, 099g/0.4m3. The total root length of Zoysia japonica Steud. which was 3, 013m/0.4m3 was the longest among the eight species. The soil of the fields consisted of sand and sandy loam. The pH of the soils ranged from 4.9 to 5.6. No differences were observed between the fields where species of Zoysia japonica Steud. and Cynodon dactylon Pers.×Cynodon transvaalensis Burtt-Davy grows, and the fields with other species based on studies of the soil physical and chemical properties.
The above results indicated that the utilization of Imperata cylindrica Beauv., Miscanthus sinensis Anderss., Shibataea kumasaca Nakai, Hedera canariensis Willd., Sasaella kogasensis Nakai var. gracillima S. Suzuki and Sasa palmata Nakai var. niijimai S. Suzuki was as beneficial as that of Zoysia japonica Steud., Cynodon dactylon Pers.×Cynodon transvaalensis Burtt-Davy.View full abstractDownload PDF (874K) -
Sombat Chinawong1992 Volume 37 Issue 3 Pages 248-250
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSA greenhouse experiment was performed to investigate the effect of water level on activities of oxadiazon, thiobencarb and butachlor to control barnyardgrass. The herbicides were applied to 7 day old seedlings using two water levels: half or full plant height. Twenty days after treatment, all three herbicides showed almost complete control of barnyardgrass in the higher water level when applied at recommended rates (1.0, 2.0 and 1.0kg ai/ha for oxadiazon, thiobencarb and butachlor, respectively) or at half of the recommended rates. In the lower water level, their efficacy was reduced when half the recommended rate was used. Greater phytotoxicity to rice plant was also observed in the higher water level.View full abstractDownload PDF (317K) -
Nobumasa Ichizen, Hitoshi Kuramochi, Makoto Konnai, Hiroshi Takenaga1992 Volume 37 Issue 3 Pages 251-252
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
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Hiroshi Matsumoto, Tohru Tominaga, Tadasi Sumiyoshi, Masumi Ishizaka1992 Volume 37 Issue 3 Pages 253-258
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
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Hiroshi Matsumoto, Tohru Tominaga, Tadasi Sumiyoshi, Masumi Ishizaka1992 Volume 37 Issue 3 Pages 259-265
Published: October 31, 1992
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSDownload PDF (821K)
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