A method how to assess the distribution ratio of net photosynthate was mathematically derived and adopted in an analysis of shading effect on photosynthate distribution in Fagopyrum esculentum, Helianthus annuus, Vicia faba, Phaseolus aureus and Cryptotaenia canadensis var. japonica. 1. In general, photosynthetic system (F) increases its dry weight proportionally to individual plant weight (W) in the initial growth stage, but it decreases its growth rate with progressing W growth. This was formulated as F=μW/(1+νW), where μ and ν are constants. Then, the distribution ratio (δ=dF/dW) of photosynthate to F was derived as δ=μ/(1+νW)2. 2. As to the plant growth in the shading experiments μ and ν were obtained by using the C-D rule24), and the δ-W relation was derived from the above formula. In Ph. Aureus δ was independent of W, and in the other species it decreased with increasing W. The depression of δ with shading was evident in F. esculentum, H. annuus and V. faba. A shade plant, C. canadensis var. japonica has the highest δ values in the 75% light and its δ values were hardly depressed with shading. The trend of change of the distribution ratio with increasing W and shading can indicate nicely the shade tolerability of plants.
A tonophilic fungus reported in a previous paper1) was compared with Eurotiumhalophilicum. A new form of Eurotium halophilicum is proposed for the fungus (Fig. 1). The fungus needs culture media hypertonicized by adding more than 40% sucrose or 15% sodium chloride for its normal growth (Figs. 2 and 3, Table 1). Cultural aspects obtained from these experiments recorded in Table 2 and Fig. 4 suggest that the fungus is tonophilic rather than halophilic. The author wishes to express her sincere thanks to Dr. Yosio Kobayasi of the National Science Museum, Tokyo, Prof. Hiroharu Indoh of Tokyo University of Education and Prof. Torao Ohtsuki of Ochanomizu University for their kind and helpful advice, and also to Prof. Clyde M. Christensen of University of Minnesota for his courtesy in supplying the author with his original strain.
From the culture medium of Penicillium islandicum, malonic acid was isolated by Yamamoto and later 3-hydroxyphthalic acid by Gatenbeck. However, these acids could not be detected in the present experiments. Among several organic acids excreted into the culture medium, the substance which is responsible for the pH-change of culture medium was identified paper- chromatographically as gluconic acid, which seems to have no direct bearing on the biosynthesis of mycelial pigments.
1) The observations of the chromosome number and the karyotype were carried out on some species of two tribes, Inuleae and Heliantheae. 2) The numbers of the somatic chromosomes were counted in two species of Inula, one species of Gnaphalium, one species of Wedelia, and one species of Bidens. 3) It is clearly shown that most of the species in the genus Gnaphalium have the basic chromosome number, b=7. 4) Though some karyotypical similarities were found between Inula ciliaris and Inulasalicina var. asiatica, some karyological differences were also recognized. 5) It may be considered that the karyotype of the Inula salicina var. asiatica was resulted by the structural change in the karyotype of the Inula ciliaris.
1) The observations of the chromosome number and the karyotype were carried out on five species of the genus Senecio and Ligularia. 2) The chromosome numbers of S. pseudo-arnica, L. angusta and L. hodgsonii are here reported for the first time. 3) The chromosome numbers of the most species of genus Ligularia appear to be hexaploids of a basic number of ten, and diploid number fifty eight with a basic number of twenty nine which may be derived from thirty, is found in L. angusta and L. hodgsonii. 4) A karyological similarity can be found in S. nemorensis and S. cannabifolius. These two species have rather symmetrical karyotypes, suggesting to be phylogenetically primititve. 5) In spite of the similarity in the external morphology between S. pseudo-arnica and S. pierotii, these species have respectively a characteristic karyotype. 6) On the basis of the karyotypical data obtained, the relationship between Senecio and Ligularia was discussed.