Journal of Weed Science and Technology
Online ISSN : 1882-4757
Print ISSN : 0372-798X
ISSN-L : 0372-798X
Volume 20, Issue 2
Displaying 1-9 of 9 articles from this issue
  • Kozo ISHIZUKA
    1975 Volume 20 Issue 2 Pages 49-54
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    Download PDF (804K)
  • III. The Selective Herbicidal Activity of Oxadiazon
    Yuji KAWAMURA
    1975 Volume 20 Issue 2 Pages 55-60
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    1) Oxadiazon, a herbicide which is active only under the light, showed in a germination test its herbicidal action against barnyardgrass (Echinochloa Crus-galli) was about ten times as strong as against rice plant. In the action to barnyardgrass, the large seeds were higher resistant to the oxadiazon than the smaller ones.
    2) In the germination test of 14 kinds of gramineous plants; corn, wheat, rice and sorghum having large seeds showed an outstanding resistance to oxadiazon compared to the other 10 kinds of which seeds were by far the smaller.
    3) In a test of transplantation to the soil incorpolated with oxadiazon using the rice and barnyardgrass which completely passed the albuminous stage, oxadiazon did not show any selectivity, giving a similar inhibition of leaf elongation and sheath browning to both plants.
    4) In a test of exposure of the germinated rice and barnyardgrass, which were soaked in oxadiazon solution in the dark at the seed stage to the light; when a period of the light exposure was the same, activity of oxadiazon differed very much depending upon the plant growth stage at the time of exposure. Rice plants seemed to be susceptible in later stage than barnyardgrass.
    From the above results, it was found that the timing of exposure to the light of oxadiazon-absorbed plants and the remained albumen level influence largely to the herbicidal activity of oxadiazon.
    Download PDF (786K)
  • IV. Influence of Soil Properties on the Herbicidal Activity of Oxadiazon under Flooded Conditions of Paddy Field
    Koichi HIRAI, Yuji KAWAMURA
    1975 Volume 20 Issue 2 Pages 61-66
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    Using 29 types of paddy field soils collected from public agricultural experiment stations in Japan, both herbicidal activity on barnyardgrass (Echinocloa Crus-galli) and phytotoxicity (the length of browning of leaf sheath) against transplanted rice of oxadiazon were examined.
    1) The herbicidal activity of oxadiazon was significantly correlated with oxadiazon concentration equilibrated in water (adsorption), pH and C. E. C. of soil. The phytotoxicity of oxadiazon was significantly correlated with oxadiazon concentration equilibrated in water, clay content and bulk density (volume weight) of soil.
    2) The herbicidal activity was significantly correlated with the phytotoxicity against transplanted rice; this means that, in the soils in which oxadiazon showed the high herbicidal activity, the influence on transplanted rice also seemed to be large.
    3) Oxadiazon concentration equilibrated in water was significantly correlated with clay content, C. E. C., bulk density of soil, but was not significantly correlated with organic matter.
    4) Although, in the case of the correlation except black volcanic ash soils, organic matter was highly correlated with herbicidal activity, phytotoxicity and oxadiazon concentration. It was showed that organic matter acted an important role for adsorption of oxadiazon.
    5) The adsorptive ability of compost of rice plant, peatmoss, cellulose and bark compost was much higher than that of bentonite, zeeklite and allophane. The adsorptive ability of oxadiazon by organic matters was as follows; peatmoss>bark compost>compost of rice plant>>cellulose. The adsorptive ability by cellulose was remarkably low. The adsorptive ability of oxadiazon by clays was as follows; allophane>bentonite>zeeklite. The difference of them was not remarkable.
    6) The results of 4) explain the reason why there was no observable correlation between oxadiazon concentration equilibrated in water and organic matter content for the different soils used in this study may be interpreted by the difference in adsorption of oxadiazon among the different organic matters contained in the individual soils.
    7) Bulk density of soil, which is significantly correlated with clay and organic matter and can be easily measured, may be an available guideline which shows the practical variation of the herbicidal activity and phytotoxicity of oxadiazon in soil.
    Download PDF (959K)
  • Koichiro KOMAI, Kunikazu UEKI
    1975 Volume 20 Issue 2 Pages 66-71
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    Some polyphenolic substances were found in purple nutsedge tubers at both stages, dormant and non-dormant. The polyphenols isolated were primarily catechol tannin of leucocyanidin and leucocyanidin-glucoside. Phenolic acids detected in the hydrolysis of the phenols with HCl or NaOH were p-coumaric acid, ferulic acid, vanillic acid, p-hydroxybenzoic acid and protocatechuric acid.
    Determining the distribution of catechol tannin in the whole plants, leucocyanidin was high in the mature tubers, seed heads and rhizomes. In nutsedge tubers, leucocyanidin contents increased at the stages of sprouting and of growth proceeded. There was much hither content of leucocyanidin in immature tubers than in mature tubers.
    Download PDF (694K)
  • (1) Herbicidal Characteristics of R-7465
    Norio SHIRAKAWA, Hiromi TOMIOKA
    1975 Volume 20 Issue 2 Pages 71-78
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    These studies were conducted to obtain some information on the properties of a selective herbicide, 2-(α-naphtoxy)-N, N-diethylpropionamide (R-7465) for rice plants. Results obtained were as follows:
    (1) R-7465 inhibited more strongly root growth than stem and leaf growth for both of graminaceous plants (such as Echinochloa Crus-galli Beauv.) and broadleaf plants. The degree of inhibiting activity for root growth was as follows: R-7465>>PCP-na>benthiocarb>>simetryne.
    (2) The activity of R-7465 applied to root was investigated under condition water cultivation. The 50% inhibition of growth was obtained at 5.8ppm of R-7465 to rice, 0.54ppm to sweet corn, 0.25ppm to barnyardgrass and 0.0092ppm to oat.
    (3) The most adequate time of R-7465 treatment was the emerging stage or the needle-leaf stage of barnyardgrass.
    (4) The movement in soil of R-7465 was small, and the downward movement of water of 6cm for two days (3cm per day) gave movement of R-7465 to 1.5cm from soil surface.
    (5) The persistence in soil of R-7465 was confirmed by 50% growth inhibiting effect, the activity persisted for 50-80 days on the treatment of 5g per are and for more than 100 days on the treatment 20g per are.
    (6) The selectivity of R-7465 for rice plant and barnyardgrass was shown apparently in trans-planting paddy field. The treatment of 10-20g per are of R-7465 showed no injury for rice plant and satisfactory control for barnyardgrass.
    Download PDF (871K)
  • (2) The Mixing Effect of R-7465 with Simetryne
    Norio SHIRAKAWA, Hiromi TOMIOKA
    1975 Volume 20 Issue 2 Pages 78-82
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    (1) The synergistic effect of R-7465 and simetryne was recoganized for barnyardgrass. The most adequate combination rate, R-7465 to simetryne was from 2:1 to 2:2.7. On the other hand, the most adequate combination for some weeds, R-7465 to simetryne was 2:1.5.
    (2) The selectivity of the formulated granules which contain both of R-7465 and simetryne (mixing ratio 2:1 and 2:1.5) was examined. In consequence, the treatment of between 6g+3g and 10g+7.5g per are showed the fine control for all of weeds and no injury for transplanted riceplants.
    (3) It was appeared that the persisteace of R-7465-simetryne combination in soil is 100 days for treatment of 6g+3g per are.
    (4) The low rate of R-7465-simetryne, such as 6g+3g to 10g+5g per are, gave no influence for oat, cucumber and crucifer planted after harvest of rice. But the treatment of more than 15g+7.5g per are gave injuries for oat particularly.
    Download PDF (588K)
  • Takeshi NAOHARA, Hisao ISHIKAWA
    1975 Volume 20 Issue 2 Pages 82-86
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    The inhibition of Hill reaction of Chlorella pyrenoidosa was investigated to perform comparative activity-tests of herbicides. Hill reaction of Chlorella cells was completely inhibited at the rate of 1ppm of DCMU at which lebel no growth of Chlorella cells occured.
    Tested compounds which inhibited Hill reaction of Chlorella similarly inhibited Hill reaction of spinach and crabgrass chloroplast at the same dose lebel. It was found that there were close relationships between the herbicidal activity for weeds and inhibitive activity for Hill reaction of Chlorella with tested photosynthesis inhibitors.
    Download PDF (497K)
  • Takahisa SUTO
    1975 Volume 20 Issue 2 Pages 87-88
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    Download PDF (264K)
  • Kunikazu UEKI, Hiroshi HYAKUTAKE, Tadao YAMADA, Katsuyoshi NOGUCHI, Mi ...
    1975 Volume 20 Issue 2 Pages 89-94
    Published: October 25, 1975
    Released on J-STAGE: December 17, 2009
    JOURNAL FREE ACCESS
    Download PDF (840K)
feedback
Top