Renge (Astragalus sinicus L.) is not self-sterile and produces self-fertilized seeds easily by artificial self-pollination, but most of seeds set in open fields might have been cross-fertilized by insects. Natural crossing percentages were studied in individual Renge plants and also in populations surrounded by other variety in the field. In a propagation field of normal red-flower variety, white-flower plants and “ever-flowering” plants grown in pots were arranged at the rate of one plant per 3.3m² during ghe glowering period. Then seeds were harvested form the white-flower plants and the eber-flowering plants individually. Characters of each progenty were examined. Because white flower or ever-flowering is recessive to red-flower or nomal type, it is considered that normal or red flower plants in the progenies are cross-fertilized, and crossing percentage of mother plants can be estimated form the ratio of normal type and recessive type the next generation. Average crossing percentage of white-flower and ever-flowering plants were 85.71±5.95 and 87.62 ±7.24, respectively (Table 1 and 2). As the crossing percentage of wheite-flower plants and ever-flowering (red-flower) plants were not so different, it was ^suggested the visiting frequsncies of insects to white-flowers and red-flowers were not defferent. A white-flower variety was cultured in square, 21.8m×21.8m, and a red-flower variety was grown around it and during the flowering period they were open-pollinated. Then seeds were harvesed from the white-flower platns seperated by direction and distance from the red-flower variety (Fig. 1). The crossing percentage of them were examined by the character of their progenies. The results are shown in tables 3 and 4. Difference of crossing percentage was not signigicant in ghe direction, but was significant in the distance. Average crossing percentage in the distance 0-0.9m from red-flower variety was 18.2%m 10, 0% for 1.8-2.7m, 6.6% for 3.6-4.5m, and inside of them, 6.1-4.5%. From the data presented, it was suggested that in natural condition crossing percentage of an individual Renge ploant was high, the fertilizing pollen being brought from its neighbourhood. Methods to protect the new variety from crossing with other varieties in the propagation field were discussed.

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Distribution of polysaccharides and their changes in quantity in shoot apez of a light-sensitive varity, Rikuu No. 20, during the morphogenesis of foliar and floral primordia were investigated by means of “PAS” reaction. Thei purpose of thie study was to get some information about the role of polysaccharides in the physiological process of flower bud differentiation. Throughout the stages of vegetative growth a large amount of polysaccharides was always observed to deposit in node, internode and pith, showing the highest concentration in node. However, when examined closely, they aer confirmed todistrbute as for as in cambium-like zone which situates in the opposite side of the yougest loaf primordium. Such is the localization and the concentration gradient of polyaccharides in shoot apez in the rice plant in its vegetative growth stage. The same localization of polysaccharides is also observed in the early stage of generative growth when whoor apex has already changed into a young ear. As the vegetative growth approaches its end, concentration of polysaccharides in the region of shoot apex increases gradually and reaches their maximum amount in the stage just before the ear differentiation. However, when the differentiation starts, their concentration in the region decreases rapidly. The situation observed here shows that the process in essentially the same in bothe the vegetative and generative development in so for as polysaccharides deposit first in the tissue having meristematic potentiality and then organogenesis follows. From the facts it is easily approved that polysaccharides play an important role in supplying necessary energy and in synthisizing proteins for the prganogenesis that follows. However, to make the inceptive cause of organogenesis flear it is necessary to investigate closely the behavior of proteins in the site of shoot apez during the critical period in which transition from the vegetative to the generative growth occurs, which will be dealt with in the second report.Some reference to the physiological cause of promotion of earing under short-day treatment of the light-sensitive variety, Rikuu No. 20, was made. It has been pointed out that less deposition of polysaccharides in shoot apex in such a variety under short-day than under normal conditions is taken to have an important bearing on the inception of generative organagenesis.

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Ears and awns of barley vary in length. TAKEZAKI⁽¹⁰⁾ made an extensive study on the characteristics of awns and ears in relation to their lengths. Short awns were associated with short or medium ars ; medium-long and long awns with long ears. He classified cultivated barley into eight different types, Ds, Dm₁, Ms, Mm₂, Mm₁, Ml, . Lm₂ and Ll, based on average awn length (i. e. s-5cm, m-8cm, m-10cm and l-15cm) and on average ear length (i. e. D-5cm, M-8cm, and L-11cm). Main varieties cultivated in Tokai-Kinki district were restricted to Mm₁ and Dm₁ types. However, these varieties were different in width of the lateral kernel rows. The ear width varide in the upper, central and lower parts of a spike. In this study, morphological observations of the ear development were made at different stage I to X were made by microscopic tests following INAMURA's method⁽⁵⁾ and the ears from the ear stage X to the heading stage by the use of magniging glass. The results of these observations which have been presented in tables and figures of the text are summerized as follows: 1)Using three varieties bilonging to the same ear type (Mm₁) and one belonging to a different ear type (Dm₁), measurements of the ear width of young ears were made at defferent locations on a spike (upper middle and lower parts) both in main and lateral kernel rows. Also the number of spikelets per ear and the internode length of spikelets were measured. Authors studied these characteristics of young ears in relation to the widths of young ears and other characters. 2)The developmental difference between Mm₁ and Dm₁ appeared during the period between March 20 and ripeness. The varietal difference sithin Mm₁ also appeared during the same period.

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Two strains of Meletha sptcata L. var. crispa BENTH. (crisp mint) grow wild in our country. The one is the strain with 48 shromosomes and the other with 54 chromosomes in somatic cells. There can be found no difference between them morphologically and the one can hardly be distinguished from the other, except for the difference in the number of chromosomes. So the authors tried to analyse the genomes of two strains of M. spicata var. crispa, using M. rotundifolia as an analyser which is one of the species with the least number of chromosom es in the genus Mentha and which is presumed to be a monogenomic diploid species with genome R. The chromosome configurations at MI of PMC's in F₁'s are shown in table 6. Genome for mulae RR-S^oS^o+a₁a₁a₂a₂a₃a₃ and RRS^cS^e were given to the strains of M. spicata var. crispa with 54 and 48 chromosomes respectively. Here, R and S^c are genomes, each composed of twelve chromosomes the former being common to M. rotundifolia and the latter being peculiat to M. spicata var. crispa. While a₁, a₂ and a₃ are supernumerary chromosomes which are semi homoogous and can canjugate with one another autosyndesistically. These chromosomes are presumed to be similar to B-chromosomes which are seen in some cereals, for instance, corn, rye, etc. Hitherto, M spicata var. crispa has been considered to be a naturaliged cariety which had been introduced from Europe. But nothing has appeared in the European literature about this variety. Recently, the authors received a clone of wild mint which had been brought back from Bhutan by S. NAKAO who had travelled there in 1958. This mint was found to be M. spicata var. crispa itself with 48 chromosomes in the somatic cells. So the authors connot frankoy accept the idea that the crisp mint is a cariety of European origin. They suggested that it was required to assumi a cautious attitude to determine the original habitat og this mint.

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For the purpose of studying the effect of selection within a population of the small turnip “Kanamachi”, the heritabilities and the degrees of dominance were estimated for weight, leaf number, neck diameter, root thickness, index of root shape and tap-rot diameter by using the data of biparental progenies within a population (the experimental procedure was the same as Experiment I. of COMSTOCK and ROBINSON, 1952)and the double of regression foefficient of progeny on male parent and on female parent. The degree of dominance was estimated from “a”=√(2(F-M)/M) and σa²/σg² by the method of Comstock et al., It was considered that the heritablilty values estimated were nearly zero weight and root diameter, and were low (5-20 percent) in the other characters except the index of root shape which showed 33-36 percent estimates. The estimates obtained by the three method agreed fairly well. In the root shape, no dominance was observed, but in the others, overdominance was detected by this mithod. Granting that overdominance observed in this experimint is partly caused by overestimation due to the method adopted, it still seems right to conclude that strong dominance effect of genes affects thses chearacters. Finally, in thses characters except index of root shape, the effect of selection cannot be exaected, because hiritability values are very low and degrees of dominance which may be overdominance are fairly higy.

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[in Japanese]

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[in Japanese]

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