By screening about 1700 soybean strains using sodium dodecyl sulfate polyacrylamide gel eledtrophoresis, two strains were found to have low levels of 7S-subunits (α, α' and β) : the amounts of α- and β-subunits in Mo-shi-dou (Gong 503) soybean seeds were about one half to one third of those found in normal soybean seeds, and the α'-subunit was not detected in Keburi soybean seeds. Mo-shi-dou (Gong 503) and Keburi soybean seeds were found to have high 11S/7S ratio, or 2. 59 and 1.61 respectively, compared with an average value of 1.12 of those of the four normal strains, Amsoy, Norin No.2, Sakagami No.2 and Raiden, by the disc gel electrophoresis. However, the two mutant strains showed similar levels of protein content compared with those of the normal strains. This indicates that it should be possible to increase 11S/7 S ratio without decreasing the protein content in soybean seeds. The average amount of the total sulfur-containing amino acids (cystine+methionine) of the two mutant strains was about 1.2 times higher than that of the four normal strains.

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The application of generation advancement in the presence of undesirable repulsion linkages was investigated based on the probability that promising genotypes are included in the F_t (t〓2) population with a given total breeding cost in F₂ to F_t generations. It was concluded that a breeding system incorporating early selection in the F₂ and F₃ is superior to the delayed selection system where segregating populations are generation-advanced until F₄ or later generations without selection.

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Kiyosawa's differential varieties for rice blast races and IKEHASHI's set representing major types of indica rice varieties in IRRI were evaluated for ability of these varieties to differentiate Philippine fungus isolates. The results indicate that the KIYOSAWA's and IKEHASHI, s sets were not suitable for differentiating Philippine isolates, although the KIYOSAWA's differential varieties are suitable for differentiating Japanese isolates and have single genes for blast resistance. However, the KlYOSAWA's differential varieties may be tentatively useful to differentiate rice blast races in a country which does not have suitable differential varieties. Reactions of Tongil added in the tests supported the assumption that Tongil had Pi-a, Pi-b and Pi-t.

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To determine the basic medium suitable for embryo culture, the growth response of embryos to different cultural condition was examined in Japanese garden iris, Iris ensata. Embryos which were isolated from ovules at about 60 days after pollination were explanted onto various cultural media (Table 1) in test tubes under aseptic condition, and were grown at about 20°C under continuous illumination. Sixty days after inoculation, germination rate, dry weight, plant height and root length were examined, and the followlng results were obtained. Nitsch's inorganic medium containing 2% sucrose and O.4-0.6% agar and being ad justed at pH 4-5 was the best as the basic medium for embryo culture of I. ensata. In all the supplements added to the basic medium, 30 ppm peptone and 5ppm gibberellin were the most effective for the growth and the germination of embryos, respectively, but these additions were not necessarily essential to embryo culture.

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Twelve Species of Brassica and allied genera collected from different ecological niches by thc second auther were grown in sand culture with Arnon's nutrient solution supplemented with 0.00M, 0.05M and 0.1M NaCl. Leaf photosynthetic rate was reduced in plants applied with NaCl, but the degrees of reduction were different among species. The degree of reduction in the species collected from the coast was slight, on the other hand, the inland species showed a remarkable reduction in leaf photosynthesis.

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The sucker-producing characteristics and their genetic variations were studied by measuring the number and dry weight of leaf axil suckers, classified here as ground and upstalk suckers, of 130 flue-cured and Japanese domestic air-cured tobacco cultivars grown in randomized block design with two replications in 1979. Data obtained from this study showed the range from 0.3 to 8.5 ground suckers per plant, from 0.10 to 8.42g per plant for their dry weight, from 2.1 to l0.7 upstalk suckers per plant and 0.62 to 23.47g for their dry weight. Matsukawa, Perevi, MC and other 27 cultivars produced many ground suckers, and BY 103, Virginia 115, Shiroenshu and other 28 cultivars produced a few ones. Cash, Consolation 402, Perevi and other 3 cultivars produced many upstalk suckers, and Odaruma, Virginia 115, BY 101 and other 8 cultivars produced a few ones. Varietal correlations among four characters, that is, the number and dry weight of ground and the upstalk suchers were of appreciable value. Heritabilities calculated from the analysis of variance were 0.784. for the number of ground suckers, 0.873 for the dry weight of ground suckers. 0.732 for the number of upstalk suckers and 0.676 for the dry weight of upstalk suckers.

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Principal component analysis of the data for 11 characters of 89 cultivars sampled at random from a large collection of Asian origin has reconfirmed the previous assertion by the junior author that the Indica-Japonica diferentiation of rice cultivars is recogni-zable on the basis of character-association patterns, although there is no key character discriminating between the two types. The probability of misclassification by a single character ranged from about 3 percent by the potassium chlorate resistance of seedling to about 40 percent by the length/width ratio of spikelets. Discriminant functions combining 3 or 4 character values gave lower probabilities of misclassification, although there still remained a few intermediate forms having recombined characteristics. The F₁ sterility relationships were almost useless for the purpose of classification. About a half of the total character variance among the cultivars was attributable to Indica-Japonica differenti-ation. The normalized genetic identity between the two types was estimated to be 0.62 from data for 28 alleles at 12 Ioci. A great number of genic differences seem to be involved in the Indica-Japonica differentiation.

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A new equipment for micro-malting was devised in 1978, by modifying the equipment which had been made in 1967 (KAWAGUCHI 1973). Features of the new equipment are as follows : 1) it enables to perform throughout steeping process and germination process with one tank, 2) the sample container is put quietly in the tank, and the germinating barley grains are turned and mixed by hands once or twice a day, 3) malting for 40 samples of 250g barley, 126 samples of 40g or 308 samples of 15g per one round becomes practicable with the new equipment, 4) all sorts of sample containers are cylindrical, 5) an automated separate start system in steeping process according to the water uptake speed is adopted to achieve the synchronized start in germination at 43-44% steeplng degree (Fig 1). Above 4) and 5) are new features added to the new equrpment made in 1978 In experiment (1), the relationships between steeping degree and malt quality were examined to know suitable steeping degree at each malting type(250g, 40g or 15g malting), using one variety as materrals As steeping degree increased from about 42% to 45 or 46%, the majority of the components of malt quality changed significantly, but malt extract in 250g and in 40g malting did not change significantly (Fig 2, Table 1) In 40g and 15g malting, root loss was high and malt yield was moderately low Therefore, it is considered to be suitable to adopt lower steeping degree (about 43%) in these two malting types than that (44-45%) in 250g malting type

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On the resistance to bacterial leaf blight, caused by Xanthomonas campetris pv. oryzae (Ishiyama 1922) Dye 1978 of Japan, the mode of inheritance and allelic relationships of the genes in three resistant IRRI rice verieties IR28, IR 29 and IR30 were studied. Analysis of the F₁ and F₂ populations from the crosses between the IRRI varities and susceptible Japanese varieties Toyonishiki, Todorokiwase and Kinmaze revealed that in these IRRI varieties two major genes controlled the resistance to the bacterial groups I and V, and these two genes linked very closely with a recombination value of 2.1% Evidences from allelism tests indicated that these genes were located on the identical loci with two known genes of Kogyoku, Xa-1 and Xa-kg respectively. Howvever, the IRRI varieties were different from Kogyoku in the response of resistance at seedling stage. Hence, it was concluded that those genes should be treated in distinction from Xa-1 and Xa-kg. These results suggest that the gene of the IRRI varieties resistant to bacterial group I and the gene resistant to bacterial group V are multiple alleles at Xa-1 and Xa-kg loci, respectively. The former gene was designated as Xa-1^h and the latter gene as Xa-kg^h. The significance of these newly-discovered genes was discussed from the standpoint of breeding for bacterial leaf blight resistance.

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