Abstract
When rice plant is low or medium in nitrogen concentration at about 30 days before earing, the top dressing so called "Hogoe" is effective on grain yield. If rice plant is high in nitrogen, however, this top dressing increases susceptibility of plant to pathogens and the fear of damage by unfavorable weather. For this reason, to examine the nitrogen status of plant before this top dressing seems to be very useful. In this experiment, based on previous results that asparagine appeared only when rice plant was high in nitrogen, the author found relationship between the effectiveness "Hogoe" and the nitrogen status of plant assessed by asparagine test. The utilisation of asparagine test as a guide for "Hogoe" should be very hopeful.
