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Volume 36 (1991)
- Issue 4 Pages 307-
- Issue 3 Pages 201-
- Issue 2 Pages 97-
- Issue 1 Pages 1-
- Issue SupplI Pages 2-
Volume 36, Issue 2
Displaying 1-19 of 19 articles from this issue
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Yukio Ishimine1991 Volume 36 Issue 2 Pages 97-108
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Kazuo Chiba1991 Volume 36 Issue 2 Pages 109-117
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSYield loss and growth inhibition in rice due to the competition with Scirpus planiculmis Fr. Schm. plants were analyzed. The results are as follows:
1) A sample of 100g air-dry weight of S. planiculmis plants per m2 at harvest decreased rice yield by approximately 20%. The degree of yield decrease per unit weight of the weed appeared to be considerably high as compared with that caused by the other weed species of paddy fields.
Among the yield components of rice, the panicle number was most seriously affected by the weed, followed by the number of grains per panicle (Fig. 1 and 2).
2) The decrease in the panicle number was ascribed to two mechanisms: 1) suppression of tillering and 2) increase of the number of non-productive stems (Fig. 3).
3) The severity of the weed damage caused by S. planiculmis is due to the fact that weed emergence after transplanting of rice seedlings occurs early and shoots are large immediately after emergence and, furthermore, the RGR at early stages is higher than that of the rice plant (Fig. 11).
4) The rice plant and S. planiculmis compete with each other for both nutrients and light. The competition for nutrients precedes, that for light. However, it is considered that the degree of the damage of the rice plant due to the competition for nutrients with S. planiculmis is higher than that caused by Echinochloa crus-galli (L.) Beauv. var. crus-galli or Cyperus serotinus Rottb. which is associated with the competition for light. Due to the competition with the rice plant, the maximum nitrogen absorption of S. planiculmis at harvesting time was about 5.0kg/10a (Table 2 and Fig. 8).View full abstractDownload PDF (1997K) -
Mamoru Nashiki, Tetsuo Suyama, Ryohei Meguro, Tadashi Kato1991 Volume 36 Issue 2 Pages 118-125
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe current studies were carried out to evaluate the forage nutritive value (in vitro dry matter digestibility and chemical composition) of R. obtusifolius L. that is commonly found in established stands of perennial forage crops in comparison to two forage crops, Festuca arundinacea Schreb and Trifolium repens L. and four weed species, Digitaria ciliaris (Retz.) Koeler, Echinochloa crus-galli L., Malachium aquaticum (L.) Fries and Polygonum longisetum De Bruyn in a grazing pasture composed of a Festuca and Trifolium mixture from June through September (Table 1).
The results are as follows:
1. R. obtusifolius showed the lowest in vitro dry matter digestibility (IVDMD) regardless of the growing stage among the two forage and five weed species, which was ascribed to the low percentages of organic cellular contents (OCC) and cellulase soluble fraction (Oa) in organic cell walls (OCW) as well as the high percentage of acid detergent lignin (ADL) in this species (Table 2, 3). R. obtusifolius showed a high content of crude protein (CP) except from bloom to the fruiting stage in June, with a mean content of 28% (Table 2).
2. R. obtusifolius showed a higher content of minerals except sodium, especially potassium and magnesium comparedto F. arundinacea and other weed species at all the growing stages (Table 4, 5). Regarding mineral imbalances and anti-quality components of R. obtusifolius causing health problems in cattle the Ca/P ratio was rather high and the nitrate-N concentration reached a value of 0.22% resulting in nitrate toxicity in ruminants, since the ratio of K/(Ca+Mg) on a meq basis did not exceed 2.2 it was assumed that the absorption of such forage by ruminants may not lead to grass tetany or hypomagnesemia (Table 6).
3. It is considered that the low digestibility of R. obtusifolius with a low palatability may be responsible for the low nutritive value in spite of the high concentration of CP and minerals for animals, in addition to some toxic components. Also, the large accumulation of minerals in R. obtusifolius resulting from the absorption of a large amount of nutrients in soil enabled it to grow profusely and compete with forage crops and other weeds in the pasture.
On the basis of these results, it is concluded that R. obtusifolius can not replace the use of supplements and should be eliminated in a pasture from the viewpoint of production of high quality forage.View full abstractDownload PDF (874K) -
Kenji Usui, Srisom Suwanwong, Hiroyuki Watanabe, Kozo Ishizuka1991 Volume 36 Issue 2 Pages 126-134
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSNormal carrot cell suspension treated with BSM showed changes in the free amino acid levels. Most of the amino acids either increased or remained constant, but the levels of valine and leucine decreased markedly. The level of isoleucine was significantly unchanged. In BSM-tolerant cells the free amino acid levels were not decreased. Exogenously supplying these three amino acids to normal cells provided the most effective recovery of growth inhibition.
Normal cells treated with GLY showed changes in the free amino acid levels. Most of the amino acids either increased or remained constant. The tolerant cells had higher levels of phenylalanine and tyrosine than that of normal cells. The combination of phenylalanine, tyrosine and tryptophan showed the best recovery of GLY-induced growth inhibition.
In GLU-tolerant cell suspensions, the GLU-treated normal cells had a high level of accumulated ammonia whereas, the tolerant cells did not. GLU-induced growth inhibition was recovered by glutamine incorporation.
Exposure to GLU had no effect on ammonia accumulation in tolerant cells, suggesting that these cells may have an effective mechanism to avoid a high intracellular ammonia level.
Based on these findings, the high level of valine, leucine and isoleucine in BSM-tolerant cells; phenylalanine, tyrosine in GLY-tolerant cells; and glutamine in GLU-tolerant cells may be the result of adequate synthesis supported by overproduction of the target enzyme and/or production of a target enzyme insensitive to the herbicide which is involved in the tolerance mechanism.View full abstractDownload PDF (839K) -
Kenji Terai1991 Volume 36 Issue 2 Pages 135-141
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThis paper offers a demographic treatment of density data acquired between 1977 and 1978 for Rumex obtusifolius L. in grazed grasslands near Sendai city, northeastern Japan. The population density rapidly increased in late spring and summer, and decreased appreciably in autumn (Fig. 1), but the fluctuations in population density were small in comparison with the large number of individuals lost and gained. There was no positive relationship between recruitment and mortality during the study period (Fig. 2). Recruitment was generally high on bare soil areas and at high temperatures during late spring and summer, while the peak in mortality occurred when the pasture was in its most passive growth after summer. There was a different pattern of mortality among the cohorts of individuals established at different times of year (Fig. 4). They had different mortality risks (Fig. 3), and the number of surviving individuals over the period of observation was relatively high in cohorts of earlier emerging individuals when compared with the number of those emerging later (Figs. 5 and 6). Differences in the patterns of mortality depending on age of individuals, time of establishment, presence of associated species, and trampling with grazing behavior were discussed.View full abstractDownload PDF (612K) -
Teruo Terasawa, Shohei Hirose, Hiroomi Asano1991 Volume 36 Issue 2 Pages 142-147
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe effect of conditions of fertilizer applications on the growth characteristics of large crabgrass and common purslane was investigated. Both weeds were grown under two different conditions of fertilizer application, i. e., Nitrogen 0kg/10a (N-0) and 50kg/10a (N-50) during 4 years with one generation a year. Seeds obtained under the above conditions. i. e., seeds of the 5th generation were grown in the N-0 or N-50 plots in order to analyse the effect of past record of fertilizer application on the growth and seed production of the weeds.
1) A large number of growth parameters in the N-50 plot showed higher values than those of the N-0 plot in the test for the 5th generation regardless of past record (Fig. 1, Table 1).
2) After 4 generations under different conditions of fertilizer application. the plant length. stem weight and the number of green leaves of large crabgrass grown under the N-0 conditions showed higher values the plot with a past record of N-0 than in the N-50 plot, in the test for the 5th generation. Subsequently. CRE in the N-0 plot was larger than in the N-50 plot in the 5th generation. No differences in various growth parameters of large crabgrass grown under the N-0 and N-50 application rates were not observed in the N-50 plot. However the growth parameters in common purslane showed large values in the plot with a past record of N-50 (Fig. 1. Table 2).
3) Regardless of the past records of fertilizer application. the individual variations in both weeds in the N-0 plot was increased in the test for the 5th generation. The individual variations for both weeds with the N-0 past record at the 5 th generation were greater under the N-0 conditions than under the N-50 conditions. Such a tendency, however, was not observed in both weeds with past record of N-50 (Fig. 1, Table 3).
4) Growth characteristics of both weeds in relation to the adaptation to the environment were discussed based on the above results.View full abstractDownload PDF (619K) -
Ecological Studies on Environmental Adaptation in WeedsTeruo Terasawa1991 Volume 36 Issue 2 Pages 148-152
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe effect of past record of plant density on the growth and seed production of large crabgrass and common purslane was investigated. Both species were grown under two different plant density conditions, i. e., 5 plants per 1/2, 000a pot as low density in both weeds, 100 plants per pot in large crabgrass and 65 plants per pot in common purslane as high density. Cultivationu nder such conditions was continued for 4 years with one generation a year. Seeds were obtained under the above conditions, i. e., seeds of the 5th generation were grown under low or high plant density conditions.
1) Effect of past record of plant density on the growth parameters was not observed in the case of low plant density conditions in the test for the 5th generation, except for the plant length of large crabgrass (Fig. 1, Table 1).
2) When large crabgrass with different past records of plant density was grown under high plant density conditions, the number of green leaves, the leaf area and seed weight of the plants with a past record of low density were greater than those of the plants with a part record of density. These differences were not observed in common purslane (Fig. 1, Table 2).
3) There were different kinds of individual variations in the past record of growth conditions between both weeds. Although individuals with different reactions to plant density were observed in each plot, the effect of the actual plant density on the growth parameters in the 5th generation was more pronounced than that of the past record of plant density, except for several growth parameters of large crabgrass in all the plots (Fig. 2).View full abstractDownload PDF (562K) -
Hiroaki Watanabe, Masuji Miyahara, Hidejiro Shibayama1991 Volume 36 Issue 2 Pages 153-161
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSField experiments were carried out to investigate the growth and seed production of Scirpus juncoides Roxb. subsp. juncoides in paddy fields transplanted with young rice seedlings. The results obtained are as follows;
1. In a bare paddy field without rice plants, about 9, 700 seeds per plant were produced when the Scirpus seedlings emerged on June 18. More than 3, 000 seeds per plant were produced by the plants which emerged before July 16, although the seed number was smaller when the seedlings emerged later.
2. In a paddy field with transplanted rice, the number of weed seeds per plant was about 100 when the seedlings emerged immediately after rice transplanting on June 18. Heading of S. juncoides was not observed when the seedlings emerged after July 16, thirty-two days after rice transplanting. Most of the seeds were not mature when the seedlings emerged eighteen days after rice transplanting, because the duration of the grain filling period of S. juncoides was insufficient for seed maturation before rice harvesting time. Accordingly it was shown that the plants produced few mature seeds when seedlings emerged more than one month after rice transplanting.
3. The plants emerging from over-wintering buds, which grew more rapidly in the early stage of rice cultivation than those from seeds, produced 1, 500 seeds per plant in the paddy field with rice plants, and 17, 000 seeds per plant in the bare paddy field.
4. The number of seeds of S. juncoides per plant was not different among emergence densities of more than 500 plants per sq. meter. About 65, 000 seeds per sq. meter were scattered on the paddy soil surface at the density of 1, 000 plants per sq. meter. However fewer seeds were produced when the plant emergence density was higher, because the plant density at the rice harvesting time decreased due to competitive pressure.
5. The number of seeds per plant was highly correlated with the foliage air-dry weight, although the values of latter parameter varied with the emergence time and plant density of S. juncoides and the growing conditions in paddy fields.View full abstractDownload PDF (1086K) -
Jeung Joo Lee, Hiroshi Matsumoto, Jong Yeong Pyon, Kozo Ishizuka1991 Volume 36 Issue 2 Pages 162-170
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSSelectivity mechanisms of diphenyl ether herbicide oxyfluorfen ((2-chloro-4-trifluoromethylphenyl)-3′-ethoxy-4′-nitro-phenyl ether) and chlomethoxynil (2, 4-dichlo-rophenyl-3′-methoxy-4′-nitrophenyl ether) in rice (Oryza sativa L.), barnyardgrass (Echinochloa oryzicola Vasing.), sorghum (Sorghum bicolar Moench), corn (Zea mays L.), tomato (Lycopersicon esculentum Mill), cabbage (Brassica oleracea L.), radish (Raphanus sativus L.), cucumber (Cucumis sativus L.), and buckwheat (Fiagopyrum esculentum Moench) were studied. Oxyfluorfen showed higher herbicidal activity to the plants than chlomethoxynil, and the plants absorbed more of the former. However, they metabolized 14C-chlomethoxynil more rapidly than 14C-oxyfluorfen. This greater absorption and lower metabolism of oxyfluorfen by the plants are considered main factors of its higher phytotoxicity.
In oxyfluorfen treatment, rice and corn were more tolerant and absorbed less of the herbicide than other plants. Tomato showed very severe damage and had the highest absorption rate. Degradation of 14C-oxyfluorfen in the plants was very limited. Absorption of oxyfluorfen by the plants is thus possibly one factor of its selectivity.
In chlomethoxynil treatment, rice and corn were more tolerant than other plants and showed the lowest absorption rate. Metabolism of 14C-chlomethoxynil was greatest in rice plants. Rates of absorption and metabolic activity of chlomethoxynil in these plants are considered to relate to its selectivity.View full abstractDownload PDF (825K) -
Toshimi Tanaka, Masami Oyamada1991 Volume 36 Issue 2 Pages 171-175
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSThe effects of paddy soil properties on the herbicidal activity of naproanilide were investigated.
1) The herbicidal activity of naproanilide on Scirpus juncoides Roxb. differed with the type of soil collected from paddy fields in 35 locations in Japan. The I90 ranged from 0.5 to 2.0ppm for the soils collected from 29 locations, while around 4ppm for the soils 4 locations from, HOKKAIDO (NANPOLO), TOCHIGI (UTSUNOMIYA), IBARAGI (USHIKU) and KANAGAWA (FUJISAWA). High carbon content and strong ability to adsorb naproanilide and NOP were the common characters of the 4 soil types.
2) Carbon content, nitrogen content and ability of soil to adsorb naproanilide and NOP were highly correlated with the herbicidal activity of naproanilide.
3) Lightness, hue and saturation of soil color were correlated with the herbicidal activity of naproanilide, and the soil color was correlated with the Kd of adsorption of naproanilide and NOP.
4) It was estimated that the reduction of herbicidal activity of naproanilide in the paddy fields was due to the strong adsorption of naproanilide and NOP by the soil containing a high carbon content. It was suggested that the identification of the soil color was a simple method for estimating fluctuations of the herbicidal activity of naproanilide in paddy fields.View full abstractDownload PDF (545K) -
Keiko Nakatani, Tokuichi Kusanagi1991 Volume 36 Issue 2 Pages 176-182
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
JOURNAL FREE ACCESSFour species of upland weeds, i. e., Chenopodium album L., Polygonum persicaria L., Digitaria adscendence Henr. and Echinochloa crus-galli Beauv. var. praticola Ohwi, were sown in a field at monthly intervals from April through September or October for 3 years from 1983 to 1985, to obtain different emerging time of the weeds.
The period from sowing to heading or flower-bud formation in the weeds sown from April to August was influenced by photoperiodism, unlike that in the weeds sown after September.
The limit of the sowing time for heading or flower-bud formation corresponded to the end of August in D. adscendens and E. crusgalli, and early October in C. album and P. persicaria, and that for seed maturation corresponded to early September in C. album and the end of August for the other three species.
The plant length or stem length and top dry weight of the weeds were reduced by the delay in the sowing time. The degree of reduction was large in C. album and small in P. persicaria.
The amount of seeds in the four species tended to depend on the growth of the top. The weight of the seeds per plant was large in the weeds sown from April through June, but the thousand seed weight of the weeds except for C. album decreased with the delay in the sowing date, though that of C. album increased in the August sowing.
When the sowing date was delayed, the RE (Reproductive Effort) of P. persicaria decreased, while the RE of C. album, D. adscendens and E. crus-galli increased.
In the case of C. album, partition of dry matter production to reproductive organs started at the late growth stage in the May sowing, but at the early growth stage in the August sowing. In the case of P. persicaria, however, the partition to the reproductive organs started at the early growth stage in both May and August sowings. Therefore it was demonstrated that the difference in the partition shift depending on the sowing date led to differences in the RE shift for C. album and P. persicaria.View full abstractDownload PDF (743K) -
Eiji Tanesaka1991 Volume 36 Issue 2 Pages 183-186
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Srisom Suwanwong, Kenji Usui, Kozo Ishizuka1991 Volume 36 Issue 2 Pages 187-190
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Daiichiro Miyajima1991 Volume 36 Issue 2 Pages 190-193
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Toshimi Tanaka, Yoshio Takasawa1991 Volume 36 Issue 2 Pages 194-196
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Tadashi Sumiyoshi, Youichi Sato, Jiro Harada1991 Volume 36 Issue 2 Pages 197-199
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Makoto Numata1991 Volume 36 Issue 2 Pages i-iii
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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Tetsuo Takematsu1991 Volume 36 Issue 2 Pages iv-vi
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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James D. Riggleman1991 Volume 36 Issue 2 Pages vii-xiv
Published: September 02, 1991
Released on J-STAGE: December 17, 2009
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