Studies on the Growth Types of Mat Rush : II. Determination of the growth stage exceedingly related to the long stem yield and its difference between tiller type (Asanagi) and elongation type (Shimomasuda-zairai) of mat rush cultivar

摘要

In the previous paper, the authors parted the growing season of mat rush into four stages, i.e. the winter stage, the spring stage, the tillering stage of the long stems and the elongation stage of them. This experiment was carried out to clarify the growth stage exceedingly related to the long stem yield among the three stages of the latter and its difference between two types of mat rush cultivar. And the abilities for tillering and stem elongation at each stage were investigated by means of lowering or raising the soil-water temperature in each stage. And also the relationship between the long stem yield and the growth habitat of tillering :ad stem elongation at each stage was studied. The results are summarized as follows: 1. In both the types of cultivar, tillering was most affected at the spring stage by soil-water temperature, and stem elongation was affected to the same extent among the three stages. During the growing period, tillering of "Asanagi" was not so affected as that of "Shimomasuda-zairai", but stem elongation of "Asanagi" was more affected than that of "Shimomasuda-zairai". 2. The number of stems per a hill at harvest time was closely related to the growing at both the spring stage and the tillering stage of the long stems. The ratio of the number of the long stems to the total number of stems per a hill had much to do with the growing at the elongation stage of the long stems in "Asanagi" and at both the tillering stage of the long stems and the elongation stage of them in "Shimomasuda-zairai". Consequently, the long stem yield was closely related to the growing at both the spring stage and the tillering stage of the long stems in "Shimomasuda-zairai". 3. It was suggested that much attention had to be paid to the degree of the growth at the tillering stage of the long stems in the cultivation of mat rush and the optiaml standard of the growth at this stage was fairly smaller in "Shimomasuda-zairai" than in "Asanagi".