Publications by authors named "Shigenori Okawa"

Article Synopsis
  • - The study explores how herbicide resistance evolves in the weed Monochoria vaginalis, which has five copies of the ALS gene, a target for sulfonylurea herbicides.
  • - Researchers analyzed several populations across Japan for herbicide sensitivity and genetic variations in ALS, discovering over 60 resistant populations with mutations linked to MvALS1 and MvALS3.
  • - The findings suggest that higher expression levels of certain ALS genes (MvALS1 and MvALS3) drive the evolution of resistance, indicating that gene expression plays a crucial role in this process.
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In this study, we propose a method for estimating the risk of agricultural damage caused by an invasive species when species-specific information is lacking. We defined the "risk" as the product of the invasion probability and the area of potentially damaged crop for production. As a case study, we estimated the risk imposed by an invasive weed, Sicyos angulatus, based on simple cellular simulations and governmental data on the area of crop that could potentially be damaged in Miyagi Prefecture, Japan.

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Low irradiance in the early phase of grain filling in rice often results in a low grain yield, but its effects on the partitioning of previously or recently assimilated carbon within the plant or panicle have not been seriously examined. The objective of this study was to demonstrate the effect of shading during the different stages in the early phase of grain filling on the partitioning of previously or recently assimilated carbon among constituent organs and into superior and inferior spikelets of the panicle in rice (Oryza sativa L. 'Sasanishiki') plants using 13C as a tracer.

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