Journal of Weed Science and Technology
Online ISSN : 1882-4757
Print ISSN : 0372-798X
ISSN-L : 0372-798X
Search
Advanced search
OR
Browse
Search
Volume 55, Issue 2
Displaying 1-9 of 9 articles from this issue
Show all abstracts
    • |<
    • <
    • 1
    • >
    • >|
President's Message
Reports
  • Variation in wheat cropping systems affects wild oat (Avena fatua) demogra-phy:an experimental evaluation using pots
    Motoaki Asai, Yasuhiro Yogo
    2010 Volume 55 Issue 2 Pages 55-61
    Published: 2010
    Released on J-STAGE: August 27, 2010
    DOIhttps://doi.org/10.3719/weed.55.55
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    A factorial experiment was conducted under outdoor conditions from September 1999 to June 2001 to assess the effects of winter wheat cropping systems on the demography of wild oat (Avena fatua L.), a problematic weed in winter cereals. The simulated cropping system, and in particular tillage, significantly affected the number of wild oat plants per pot. The number of wild oat plants increased under a summer till-autumn till system, whereas plant number decreased under a summer no-till system. When no-till in summer was followed with no-till in autumn, wild oat disappeared in certain plots by June 2001. The decrease in the number of wild oat plants under a summer and autumn no-till system was likely to be related to the advanced emergence induced by no-till leading to relatively reduced survival. Application of calcium cyanamide prior to seeding of wheat increased wheat ear number and wild oat panicle number. Under a summer no-till system, the number of wild oat plants increased with calcium cyanamide application, indicating stimulation of emergence. These results suggest that tillage regime can have a strong effect on wild oat demography in winter wheat fields, indicating that integrated control of wild oat should include no tillage throughout summer and autumn.
    View full abstract
    Download PDF (985K)
  • Control effects of soil-applied herbicides in soybeans sprayed over wheat-residue mulch
    Soichi Nakayama, Keiko Nakatani, Hideo Hamaguchi
    2010 Volume 55 Issue 2 Pages 62-68
    Published: 2010
    Released on J-STAGE: August 27, 2010
    DOIhttps://doi.org/10.3719/weed.55.62
    JOURNAL FREE ACCESS
    Show abstractHide abstract
    To determine the effectiveness of 11 soil-applied herbicides in no-till double-cropping soybeans after wheat, we studied the control effects of these herbicides sprayed over wheat-residue mulch. First, we evaluated the effect of rainfall treatments (0-4mm), which were applied 24hr after herbicide application, on the control effects of prometryn-metolachlor (PM) sprayed over 4,000kg/ha of wheat straw at 0.8+1.2kg a.i./ha in 1,000L/ha of water. PM controlled Amaranthus patulus Bertoloni effectively (>99%) under all rainfall treatment conditions including no rainfall and no significant difference (p=0.40) was observed in the number of surviving A. patulus plants between the different rainfall treatments. On the basis of the results of the first experiment, we conducted the second experiment under no-rainfall condition to determine the control effects of the 11 herbicides on A. patulus and barnyard millet. The herbicides were sprayed over 6,000kg/ha of wheat straw at the respective maximum registered doses in soybeans in 1,000L/ha of water. Wheat straw considerably inhibited the control effects of simazine and diuron on the test plants remarkably (64.5% and 54.7% in wheat-residue plots versus 98.8% and 100% in no-residue plots, respectively). The other nine herbicides controlled the test plants effectively (>99%); however, in the case of some herbicides, significant differences (p< 0.05) were observed in the number of surviving plants between residue plots and no-residue plots. Therefore, we concluded that simazine and diuron were less effective than the other nine herbicides in the case of no-till soybeans.
    View full abstract
    Download PDF (838K)
The Society Award Lectures
Note
    • |<
    • <
    • 1
    • >
    • >|
feedback
 Top