All issues
Volume 42 (1997 - 199･･･
- Issue 4 Pages 307-
- Issue 3 Pages 189-
- Issue 2 Pages 57-
- Issue 1 Pages 1-
- Issue Suppl Pages 2-
Volume 42, Issue 3
Displaying 1-16 of 16 articles from this issue
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Matsuo Itoh, Satoshi Kobayashi, Katsura Manabe, Michihiko Takahashi1997 Volume 42 Issue 3 Pages 189-196
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSA study was conducted in 1995 to compare the structure of summer weed communities following winter weed control at two different times. The comparison was based on the measurement of vegetative and reproductive organs of constituent species in three orchards in Kagawa and Okayama. At the time the study began, these orchards were dominated by Setaria faberi Herrm. and Digitaria ciliaris (Retz.) Koeler. When winter weeds were controlled in late March, S. faberi became dominant, showing more than 60% relative dry weight (an index of dominance); D. ciliaris was subdominant. By contrast, the plots having had weed control in late April were dominated exclusively by D. ciliaris (about 80% relative dry weight), followed by S. faberi. Seed number of the dominant species, either S. faberi or D. Ciliaris, was greater than that of the subdominant. The relative dry weight was positively correlated to relative density in both species. When the relative density of either species increased, that species became dominant. When S. faberi became dominant after early weed control, its relative dry weight increased proportionately to the increase of relative mean dry weight (an index of plant biomass). S. faberi was significantly greater in weight and length than D. ciliaris at harvest, partly because S. faberi started emerging slightly earlier in April (one leaf stage difference). By contrast, when D. ciliaris was dominant after late weed control, no clear relationship was found between relative dry weight and relative mean dry weight. There was no distinct difference in plant size between S. faberi and D. ciliaris at harvest. These results suggest that S. faberi which emerged after early winter weed control may have dominated the fields by virtue of having suppressed the growth of D. ciliaris. Consequently, the change of dominant species may have been affected both by plant density of each species and by species-interaction.View full abstractDownload PDF (873K) -
Md. Amzad Hossain, Yukio Ishimine, Hitoshi Kuramochi, Hikaru Akamine, ...1997 Volume 42 Issue 3 Pages 197-205
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSTorpedograss (Panicum repens L.) is a perennial rhizomatous weed in 19 crops, orchards, golf courses and fallow lands in tropical and subtropical areas. Twenty seven different herbicides with different characteristics were tested for their herbicidal efficacy on torpedograss on Okinawa island. Diuron, isouron, buthidazole, karbutilate, isoproturon, hexazinone, ametryne, cyanazine, atrazine, primisulfuron-methyl, nicosulfuron, imazethapyr, fenoxaprop-ethyl, haloxyfop, fluazifop-butyl, cyhalofop-butyl, glyphosate, glufosinate, bialaphos, asulam, chlorthiamid, mefluidide, dalapon, quinclorac, prohexadione calcium, sulcotrione and sethoxydim were studied. Among them the following herbicides showed higher efficacy on torpedograss. Hexazinone at 5.0-10.0kg ai/ha controlled 47-60% of shoots, 95-100% of rhizome buds and 48-59% of corms. Glyphosate at 1.5-3.0kg ai/ha controlled 40-67% of shoots, 82-97% of rhizome buds and 62-65% of corms. Glufosinate at 1.5-3.0kg ai/ha controlled 80-90% of shoots, 91-100% of rhizome buds and 49-88% of corms. Bialaphos at 1.5-3.0kg ai/ha controlled 57-67% of shoots, 56-72% of rhizome buds and 25-50% of corms and asulam at 2.0-4.0kg ai/ha controlled 60-87% of shoots, 92-95% of rhizome buds and 90-92% of corms. The experimental results suggested that hexazinone, asulam, glyphosate, bialaphos and glufosinate were effective herbicides for torpedograss control on Okinawa island.View full abstractDownload PDF (860K) -
Kiyoshi Suzuki, Takashi Kume, Tetsuo Takematsu1997 Volume 42 Issue 3 Pages 206-213
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSNovel N-acyl-N-phenyltetrahydrophthalamic acid derivatives were synthesized and their herbicidal activity and selectivity were evaluated by a pot test in a greenhouse.
1. Pre-emergence herbicidal activity and selectivity under paddy conditions.
In the structure of N-acyl-N-phenyl-3, 4, 5, 6-tetrahydrophthalamic acid derivatives, a 3-butyn-2-yloxy group at the 5 position of the aniline moiety (R1) was found to be the major determinant for herbicidal activity toward Echinochloa oryzicola Vasing. and selectivity between rice and Echinochloa oryzicola (Table 1). Introduction of a 3-fluorobenzoyl group (R2) on the amide nitrogen atom significantly decreased the rice phytotoxicity without a concomitant loss of herbicidal activity (Tables 2 and 3). In addition, 2-methoxyethyl esters (R3) showed on equal to or higher activity than the corresponding methyl esters (Table 4). Among the compounds tested, 5 novel N-aryl-N-phenyltetrahydrophthallamic acid derivatives were selected for their strong herbicidal activity and high selectivity. 2. Post-emergence herbicidal activity under paddy conditions.
Post-emergence herbicidal activity toward Echinochloa oryzicola, Rotala indica Koehne., Cyperus difformis L., Scripus juncoides Roxb., Monochoria vaginalis Presl. in water application was evaluated for the selected compounds. Among them, 2-methoxyethyl N-(3-fluorobenzoyl)-N-[4-chloro-2-fluoro-5-(3-butyn-2-yloxy) phenyl]-3, 4, 5, 6-tetrahydrophthalamate (CUH-35) showed the highest activity and effectively controlled these paddy weeds at a dose of 30g a. i./ha except for Scripus juncoides, without adverse effect on transplanted rice (Tables 5 and 6).View full abstractDownload PDF (807K) -
Kiyoshi Suzuki, Takashi Kume, Tetsuo Takematsu1997 Volume 42 Issue 3 Pages 214-220
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSNew N-acyl-N-phenyltetrahydrophthalamic acid derivaties have been found to show a high level of post-emergence herbicidal activity to toward weeds, without injuring soybean.
1. Post-emergence herbicidal activity toward Abutilon theophrasti Medic.
In an attempt to optimize the herbicidal activity of this series of compounds, substitution at the 5 position of the aniline moiety (R1) was found to be the major determinant for enhancing the herbicidal activity while avoiding injury to soybean (cv. Hokai), and the methoxycarbonylmethylthio group appeared to be most effective (Table 1). Alkyl esters mainly showed a higher activity than other aliphatic esters (Table 2). Highest herbicidal activity was obtained with an ethyl moiety at the R2 position. Among the compounds tested, 4 new derivatives (4, 11, 15, 16) were selected for their strong herbicidal activity and superior selectivity.
2. Post-emergence herbicidal activity toward several upland weeds.
Herbicidal activity of these compounds with high performance was investigated for other important weeds in upland fields (Table 3). As a result, it was shown that methyl N-propionyl-N-(4-chloro-2-fluoro-5-methoxycarbonylmethylthiophenyl)-3, 4, 5, 6-tetrahydropthalamate (CUH-38, 11) displayed the strongest activity among the compounds tested (Tables 3 and 4).View full abstractDownload PDF (655K) -
Mitsuhiro Matsuo, Hidejiro Shibayama1997 Volume 42 Issue 3 Pages 221-226
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe distribution of ducksalad, Heteranthera limosa, a naturalized weed in paddy areas of the southern part of Okayama Prefecture, was surveyed in 1995 about 20 years after invasion. The species infested paddy fields at 19 points in 11 districts among 44 points in the 34 districts surveyed. The species occurred mainly in unplanted or partly unplanted rice fields along the Kurashiki River in these 19 points. Areas of distribution were almost the same as those surveyed in the past 20 years. Ducksalad covered more than 80%, at most, of the area of infested paddy fields. The length of the individual plants of the species was larger in unplanted paddy fields or in unplanted areas of rice fields, while the size of the plants infesting among rice hills was smaller due to competition with rice.View full abstractDownload PDF (585K) -
Tetsuro Muraoka, Michiaki Kamoi, Koji Noritake1997 Volume 42 Issue 3 Pages 227-232
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSTo analyse the occurrence of surface soil separation (S. S. S.) in paddy fields, we studied the external appearance of the S. S. S. layer and the changes in the population of associated algal species in the layer.
Furthermore, we studied the role of diatoms (Bacillariophyceae) during the initial stage of layer formation.
The formation of the S. S. S. layer in paddy fields exhibited the following sequence. Firstly, the fine soil particles that accumulated on the soil surface after puddling aggregated rapidly due to the activity of diatoms, leading to the formation of a thin, light brown layer. Secondly, the diatom population continued to increase resulting in further aggregation of soil particles. Furthermore, on this stage, the increase in the photosynthetic activity of algae resulted in the accumulation of oxygen which subsequently led to the floating of the layer. Thirdly, filamentous blue-green algae (Cyanophyceae) i. e. Osillatoria sp. started to grow and then become dominant, conferring a green color to the layer. Finally, due to the large population of blue-green algae soil particles, become more tightly bound resulting in the strengthening of the layer.View full abstractDownload PDF (4977K) -
Mitsuhiro Matsuo, Hidejiro Shibayama1997 Volume 42 Issue 3 Pages 233-239
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe growth of juvenile seedlings and the development of hypocotyl hairs were investigated in Monochoria vaginalis (Burm. f.) Kunth. Experiments were conducted in petri dishes in which M. vaginalis seeds were sown in distilled water or on the flooded soil surface after the breaking of dormancy. Germinated seedlings were collected and investigated at 6, 12, 18, 24, 36, 48, 96, 120, 240 and 360 hours after seeding. Hypocotyl hairs developed from 3 to 4 cell layers in the epidermis of a ring in the basal part of the hypocotyls of these juvenile seedlings. The upper hairs in the hypocotyls elongated mainly horizontally, while the lower ones elongated mainly downward obliquely or vertically. M. vaginalis seeds started to germinate within a few hours, and developed hairs from the hypocotyls of the seedlings 6 hours after sowing of seeds. The number of hairs ranged for 100-120 in each juvenile seedling. The longest hair elongated to about 2.0mm in distilled water at 36 hours, but to about 2.5mm on the flooded soil surface at 120 hours after sowing of seeds. Root hairs developed from seminal roots at 36 hours after sowing of seeds, and the longest hair was. 1.0mm in length, although the diameter was almost the same as that of the hypocotyl hair. Approximately 80% of the seeds in a capsule of M. vaginalis germinated in distilled water, while 5% of the germinated seeds did not develop hypocotyl hairs well, and they were shorter than 1.0mm. Number of hypocotyl hairs of the seedlings did not vary with the culture medium (distilled water, flooded soil, sand, glass beads 0.2mm and 1.0mm in diameter).View full abstractDownload PDF (2118K) -
Hiroaki Watanabe, Mohd. Zuki Ismail, Nai Kin Ho1997 Volume 42 Issue 3 Pages 240-249
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSFimbristylis miliacea (L.) Vahl. is one of the most common annual sedges in direct seeded rice fields in the Muda plain, the largest double cropping area in Peninsular Malaysia. In 1989, a 2, 4-D resistant biotype was observed in a farmer's field in Kampung (Kpg.=village) Gulau where 2, 4-D had seasonally been applied as a single compound since 1975. Response of the resistant plants to 2, 4-D dimethylamine was compared to susceptible plants in a pot experiment (Fig. 1). Resistant plants recovered after the application of 2, 4-D dimethylamine at rates up to 2.78g a. i./m2, equivalent to 32 times the recommended rate, whereas the growth of susceptible plants was strongly affected at a rate of 0.087g a. i./m2, the recommended rate, and completely controlled at 0.17g a. i./m2 (two times the recommended rate) or higher (Fig. 2, Fig. 3). The 50% lethal dose (LD50) of 2, 4-D dimethylamine to resistant plants was 1.89g a. i./m2, which was 29 times higher than the LD50 to susceptible plants. Resistant plants were not distinguishable from susceptible plants in morphological characters of panicle size, spikelet length or form of nut (Table 1). Distribution of resistant plants, detected by treatment of 2, 4-D dimethylamine at a rate of 0.17g a. i./m2, was investigated in 1993 using soil samples from 100 rice fields which were heavily infested with F. miliacea in the Muda plain; resistant plants were detected in five rice fields, but not in the other 95 fields (Fig. 4). It was suggested that 2, 4-D resistant
F. miliacea had not dominated in that area. Proportion of resistant plants in individual fields ranged between 0 to 96% in Kpg. Gulau which was not correlated with the degree of F. miliacea infestation (Fig. 5). Proportion of resistant plants decreased from 85.6% in 1992 to 1.7% in 1994 in a monitored field where herbicide 2, 4-D had not been applied since 1992.View full abstractDownload PDF (2536K) -
Kangetsu Hirase, Daisuke Kishi1997 Volume 42 Issue 3 Pages 250-255
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSProperties of a new labor-saving 1kg granule containing 3 times as much active ingredient as an ordinary 3kg granule were investigated. A 1kg granule of naproanilide containing floating carrier was prepared, and release of the herbicide from the granule in water and its herbicidal efficacy were compared with a commercial 3kg granule. The 1kg granule rose to the water surface 7-15mins after application and dispersed instantaneously. Water temperature played a role, and granules rose to the surface more quickly at higher temperature. Naproanilide concentration in 25°C water into which 1kg granules had been dropped was higher than that with 3kg granules 24hrs after application. The concentration at different water depths were similar each other in both 1kg and 3kg granules. This indicates that although 1kg granules come to surface and 3kg granules remain on the bottom, naproanilide was diffused uniformly from the bottom to the surface. Herbicidal efficacy of 1kg and 3kg granules against Sagittaria pygmaea Miq. was not greatly different, even though the number of 1kg formulation granules applied in the unit area was smaller than that of 3kg granule. This is thought to be due to the higher release of the herbicide from the 1kg granules.View full abstractDownload PDF (1612K) -
Kangetsu Hirase1997 Volume 42 Issue 3 Pages 256-261
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe influence of electric conductivity (EC) and temperature of paddy water on several properties and the herbicidal efficacy of naproanilide 1kg granule containing a floating carrier were investigated. This granule surfaced 7-15mins after application, while an ordinary 3kg granule did not rise to the surface at all. The EC of paddy water affected the surfacing ratio; the ratio was 70% when EC was 100μS/cm, but it was 5% at 800μS/cm. Naproanilide concentration in water was also affected by EC; it was 0.8ppm at 100μS/cm while it was 0.3ppm at 600μS/cm. Water temperature affected surfacing ratio and naproanilide concentration in water also: more than 70% and 1.Oppm, respectively, when water temperature was 25°C, but 0% and less than 0.05ppm at 10°C. There was a correlation between surfacing ratio and naproanilide concentration in water. Herbicidal efficacy against Sagittaria pygmaea Miq. was low at higher EC and at lower water temperature. From these results, the surfacing phenomenon is important for release of naproanilide into water and its herbicidal efficacy.View full abstractDownload PDF (571K) -
Shun Kawaguchi, Yasutomo Takeuchi, Masaru Ogasawara, Koichi Yoneyama, ...1997 Volume 42 Issue 3 Pages 262-267
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSLaboratory experiments were performed to evaluate the effect of germinating rice seeds (Oryza sativa L.) on seed germination of Monochoria vaginalis (Burm. f.) Presl var. plantaginea (Roxb.) Solms-Laub (here-after Monochoria). Rice seeds (cv. Tsukinohikari) promoted the seed germination of Monochoria at all incubating temperatures except 31°C, an optimal temperature for germination of Monochoria in the light. In darkness, although under non-inductive conditions for germination of Monochoria, rice seeds dramatically induced the seed germination at all incubating temperatures. Such stimulative effects of rice seeds were observed with both nondormant and dormant seeds of Monochoria harvested in different years. Furthermore, seeds of all 12 rice cultivars tested in the experiments exhibited a stimulative effect on the seed germination of Monochoria. Ethylene and carbon dioxide released from rice seeds and seedlings seemed to be involved in the promotion of this germination. Stimulative allelochemical (s) in rice seeds or seedlings may also promote the seed germination of Monochoria.View full abstractDownload PDF (669K) -
Tetsuya Kondo, Hiroyuki Enomoto1997 Volume 42 Issue 3 Pages 268-276
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSSeveral ground cover plants were planted in rural levees in Fukui prefecture to control weeds and to improve the visual appearance. Such ground cover species are strong, spread rapidly, form a thick vegetation while producing beautiful flowers. Ajuga reptans is used most frequently among such ground cover species.
In this study, we monitored the speed at which Ajuga reptans covered plots under different planting densities, with and without the use of polyethylene mulch. We also recorded the effect on weed suppression and reduction of manual weeding time.
Weed biomass was gretaer and it took more time to weed plots planted with Ajuga reptans early after planting. This tendency was more evident in plots with a higher density than in those with a lower density. However, once the percentage of the area covered by Ajuga reptans increased, weed biomass and weeding time decreased, particularly in the plots with a higher planting density compared with those with a lower planting density.
For cover percentages of 90% and above, or alternatively ten months after planting, weed biomass was reduced and weeding time was shorter in the Ajuga reptans plots than in the bare plots. Use of polyethyene mulch considerably decreased the weed biomass and weeding time.View full abstractDownload PDF (922K) -
Fan Deng, Akiko Nagao, Ie Sung Shim, Kenji Usui1997 Volume 42 Issue 3 Pages 277-283
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSDEAE Sephacel anion exchange chromatography was used to separate glutathione S-transferase (GST) isozymes in non-treated etiolated rice shoots (4 day-old) and those treated with a combination of pretilachlor [2-chloro-2′, 6′-diethyl-N-(2-propoxyethyl)-acetanilide] and fenclorim (4, 6-dichloro-2-phenylpyrimidine).
Non-treated rice shoots contained isozymes which were active with the following substrates; CDNB: 1-chloro-2, 4-dinitrobenzene (2 isozymes), fenclorim (2 isozymes) and pretilachlor (4 isozymes). Pretreatment of the shoots with a combination of pretilachlor and fenclorim increased the activity of the constitutively-expressed isozymes that exhibited activity with CDNB, fenclorim and pretilachlor. The treatment also induced two new GST(fen) isozymes and one new GST(pret) isozyme.
The results are suggestive of the diversity of GST isozymes in etiolated rice shoots, the selective enhancement of GST isozymes by herbicides and safeners, and safeners conjugated with glutathione, resulting in selective safening action in rice.View full abstractDownload PDF (765K) -
Toshihito Yoshioka, Ken-ichi Shibuya, Shigeru Satoh, Yuji Yamasue1997 Volume 42 Issue 3 Pages 284-288
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSEthylene inhibited the mesocotyl growth of a barnyard grass Echinochloa oryzicola by 20-30% at 0.1Pa or above. In contrast, it promoted that of E. crus-galli var. praticola and paddy field and dryland types of E. crus-galli var. crus-galli by 80, 40 and 28% promotion at 0.001Pa in this order. With E. crus-galli var. formosensis, ethylene promoted or inhibited the mesocotyl growth depending on its concentration.View full abstractDownload PDF (486K) -
Tohru Tominaga, Osamu Watanabe1997 Volume 42 Issue 3 Pages 289-293
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSDownload PDF (433K) -
Yoshiaki KAWANA, Shinichi SHIRAKURA, Motoaki ASAI, Tomoko SHIBUYA1997 Volume 42 Issue 3 Pages 294-298
Published: November 25, 1997
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSDownload PDF (615K)
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