In order to analyze the morphological, physiological and genetical interactions between different cells and tissues in chimeras, we artificially synthesized intergeneric chimeras between radish and red cabbage. As a result, various morphological and physiological interactions were observed. A distinctive new type of chimera with high wax secretion (described as WWW (+wax)) on the leaves was found in the V₁ (vegetatively propagated chimeras from original V₀ plants) revertant type to radish. This new type displayed a large number of flower stalk branches and flowers, and a later flowering date than the usual revertant MMM type. When crossed with control radish, the new type showed a higher pod setting rate than the control and revertant type MMM. Microscopic observation revealed that this new type partially had complex and thicker layers in the palisade parenchyma. Isozyme analysis revealed that the new type shared the parental bands beside its new band. This finding supported the existence of cabbage cells or tissues in the new type and suggested that some interaction between two different cells or tissues had occurred. Pollen fertility observation showed that the periclinal MRR type (LI-LII-LIII layer constitution) showed the lowest pollen fertility, resulting in a lack of seeds in the backcross with control radish. Progenies derived from chimeras crossed with both parents displayed the normal radish or cabbage phenotype during three successive vegetatively propagated generations. Although intergeneric chimeras showed some common characteristics to those of interspecific chimeras, it was more difficult to obtain genetic variation in the progeny.

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Some characters of amphidiploid lines (2n=38 AACC) and sesquidiploid lines (2n=29 AAC) derived from Brassica rapa var. pekinensis (2n=20 AA) and B. oleracea var. capitata (2n=18 CC) were investigated and the effect of the C genome was studied in this report. Characters, such as plant habit, plant height, head height, head type, leaf type, outer leaf wax and midrib type etc. in the sesquidiploid lines were close to those of the respective A genome lines, whereas in the amphidiploid lines they were close to those of the respective C genome lines. C genome showed a significant dosage effect for the characters studied. Appearance of outer leaf and incisions of leaf in the amphidiploid and the sesquidiploid lines were the same as those in the respective C genome lines. Heterosis was found in interspecific hybrids for the weight of total leaves and head leaves. Dosage effect of the C genome was also found for these two characters. With the decrease in the head index, amphidiploid lines and sesquidiploid lines showed an increase in the number and weight of outer leaves and decrease in the edibility rate. Dosage effect of the C genome was detected for the Brix value of the edible parts. Principal component analysis was carried out for 19 characters with the accessions of heading type. Results showed that the first component was mainly related to the morphological characters. The second component was principally concerned with yield. Both the first and second components showed the dosage effect of the C genome genotypes used in this study. Heterosis was found for the second component in the interspecific hybrids.

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Genetic models involved in the characteristics of aerial parts, that is plant height, leaf number and the top (including the leaf, petiole, and crown) weight, were examined in sugarbeet lines (Beta vulgaris L.) for developing a breeding plan. In this study, 5 selfed O-types lines as parent and half diallel crossed F₁ lines were used as materials. Plant height and leaf number on June 29 for the early stage and Sep. 29 for the harvest stage, and top weight at harvest time were measured under direct sowing conditions in the field trial. Diallel analysis related to the genetic variances and parameters was conducted using “DIALL” developed by UKAI (1989). Epistasis was estimated from the analysis of variance for Wr-Vr. Firstly, since the epistasis effects were not conspicuous in all the traits, it appeared that the additive-dominance model fitted to them. Secondly, for the plant height, heterosis including overdominance was evident in all the F₁ and heritability in a narrow sense was low, under 30%. For the leaf number, the additive variance of the leaf number on Sep. 29 was larger than the dominance one, while heritabilities in a narrow sense on June 29 and Sep. 29 were 36.1% and 49.2%, respectively. For the top weight, although the dominance effect was relatively conspicuous, the heritability in a broad sense and in a narrow sense was estimated at 87.4% and 15.4%, respectively. Thirdly, based in the correlation analysis between all the traits, there were positive correlations between the leaf number on June 29 and Sep. 29, and also between the leaf number on Sep. 29 and top weight, while there was a negative correlation between leaf number and root weight. In conclusion, the results showed that the leaf number could be improved more efficiently and effectively than the plant height in sugarbeet. Also for improving the top weight, it is preferable to start breeding based on the leaf number.

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We evaluated the germplasm collection of 21 wild-gladiolus species, which were native to southern Africa. Wide variations were observed in plant height, leaf length, leaf width, number of leaves, tepal color, diameter of floret and number of florets among species. Dwarf species could be suitable for pot culture, and blue gladiolus cultivars might be developed from wild species having blue tepals. More than half of these species (52.3%) produced a good scent. It was considered that some species of these collections could be highly valuable breeding materials. Important information for breeding, such as days to flowering, longevity of florets, days to seed setting and number of seeds per pod in these species, was also obtained in this study. Based on flow cytometric analysis, wild gladiolus species showed a fluorescence intensity 0.9-fold to 3.5-fold higher than that of rice plant. This observation indicated that the genome size of these species showed a wide distribution, and this information might be used for the estimation of hybridity in some cross combinations, though it was difficult to estimate the ploidy of wild species using flow cytometry.

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