Histological observation of ovary culture was made in the reciprocal crosses between diploid Brassica campestris L. ssp. chinensis (L.) Makino and autotetraploid B. campestris L. ssp. (Lour.) Olsson and their control (2x×2x and 4x×4x).
The ovaries were cut from maternal plants four days after pollination and then were soon explanted aseptically in the simple and complex medium with growth regulating substances (IAA, kinetin and gibberellin), yeast extract, tomato juice, casein hydrolysate and coconut milk.
Histological observation of the embryo, endosperm and seed coat was made 11 days after explantation (15 days after pollination). The results showed that the interruption of developing embryo in 4x×2x was due to poor development of the endosperm. Degeneration of embryos in 2x×4x and 4x×4x, was due to the abnormalities of endosperm and due to poorly developed embryos.
The development of embryos and endosperm was little influenced by the medium with the growth regulating substances (IAA, kinetin, gibberellin) and was influenced in the medium added with yeast extract, tomato juice, casein hydrolysate and coconut milk. Tomato juice did not promote development of ovules. The yeast extract and casein hydrolysate promoted development of embryos and endosperm in the crosses of the control (2x×2x, 4x×4x) and 4x×2x. Coconut mlik promoted in the crosses of the control and 2x×4x.
The embryos which developed earliest were three to seven days earlier than those under natural condition in each cross combination. When development of the ovule was later than that found in natural condition, abnormalities of embryo and endosperm were observed.

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Some morphological, cytological and biochemical characteristics of the calluses, derived from tetra- and hexaploid wheat, which were grown on various media, were investigated.
Morphological characteristics: The calluses derived from the two wheat species did not differ in morphology from each other, but growth regulators, in a broad sense, caused great variation. The 2, 4-D, kenetin and adenine sulfate gave a smooth callus, casein hydrolysate produced a congregated globular callus, and IAA and NAA caused root development. Variations in the chromosome number of callus cells did not differ due to the differences in the media used and in the length of the subculture.
Esterase zymogram: Esterase zymograms were analyzed by the gel iso-electro-focusing method. Zymograms of one, four and six days old seedlings after germination differed from each other. Zymograms of calluses which had been subcultured two or three times, became stable and uniform. When 2, 4-D was added to the medium, a callus-specific band appeared four days after germination; that is, one day earlier than the histological change of the root induced by 2, 4-D. Casein hydrolysate caused the instability of band 6 (at pI 6.5) in calluses derived from both wheat species.
Protein profile: Seed protein from T. dicoccum had more acidic fractions than did T. aestivum. Protein profiles of leaves, roots and calluses did not differ between T. dicoccum and T. aestivum. Callus closely resembled roots in this regard.
Amino acid composition of protein: The amino acid composition of protein and free amino acid were analyzed with seeds, calluses grown on different media. Seeds of T. aestivum cv. Chinese Spring showed a higher content of cystine than did T. dicoccum cv. Hokudai. The calluses of Chinese Spring (D callus) grown on a medium with a high concentration of 2, 4-D showed a larger amount of glutamic acid than those grown on the other media. In contrast, the contents of aspartic and glutamic acid decreased when casein hydrolysate was added to the medium. The amounts of amino acids were decreased by the supplement of casein hydrolysate. No cystine could be detected in any callus.

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A new procedure for constructing economic weight free selection index, based on exclusively breeder's intention, is presented. In its derivation the aggregate genotype which is absolutely required in the conventional method was ignored. In this sense this method is completely new and is applicable to the case in which the relative economic weight of each trait is unknown or difficult to assess because of no available standard for the assessment.
The use of the technique to evaluate the breeder's objective whether it is attainable within a given period of time with a given selection intensity is described.
This selection index has a wide application to practical breeding operations, since it includes several conditions of constraints proposed by other workers. The formula for predicting genetic gains in those traits which are not of the breeder's primary objective is also presented.

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Volatile isothiocyanates in seed meals of various cruciferous crops were measured and were calculated as allyl isothiocyanate.
Volatile isothiocyanate was contained in all cultivars examined. Specific differences of volatile isothiocyanate content were statistically significant and seemed to be strongly connected with genome constitution, especially with bb-genome.
The correlation between content of volatile isothiocyanate and oxazolidinethione was high among the species in genus Brassica without B. campestris, being r=-0.936 (p=0.05).
Total content of volatile isothiocyanate and oxazolidinethione, classified genus Brassica according to species, was statistically significant and B. napus, B. juncea, B. carinata and B. nigra seemed to be higher than B. oleracea and B. campestris in total content.
Only in B. oleracea there was significant difference in total content of volatile isothiocyanate and oxazolidinethione among varieties.
In B. napus two interest cultivars, Tokiwa natane and Russian No. 6 natane, were found which exhibited a very low total content of volatile isothiocyanate and oxazolidinethione.
The importance to study thioglucosides in cruciferous plants not only for plant breeding, but also for botany was also discussed.

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The objective of the present study is to observe differences in growth pattern and phenotypic plasticity among wild and cultivated rice strains. Six wild (Oryza perennis) and four cultivated (O. sativa) strains were observed under various conditions. The growth pattern or the pattern of sequential changes of growth rate appeared to be characteristic of the strains. Annual wild strains showed vigorous growth for a short period around the heading time, while perennial wild strains seemed to continue vegetative growth after heading. Cultivars generally had a higher growth rate than the wild strains. In annual wild strains, the elongation of first and second internodes that usually results in heading in other strains took place after heading to lift up the panicles higher. This may help the plants to disperse seeds. They also showed a low elongation rate in the seedling stage, which appeared to be associated with prostrate habit and vigorous root growth. Phenotypic plasticity was measured in terms of standard deviations of mean character values recorded under different conditions (converted into logarithms). In the size of various organs, wild strains, particularly of perennial type, were highly plastic as compared with cultivars, though the latter were more responsive to nutritional conditions in panicle number per plant.

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The effect of genetic and environmental factors on the morphogenesis of the lower molars and the mandible in mice was investigated by the diallel cross of three inbred mouse strains, A/Jax, CBA/Jax, anc C57BL/6Jax.
1. Significant strain differences were observed in the molar size. In the first and second molars (M1 and M2), CBA strain is the largest and A and C57BL strains are of almost equal size, whereas the size of the third molar (M3) is in the order C57BL> CBA>A.
2. The degree of genetic contribution, i.e. heritability between strains, of the size of the lower three molars was estimated. The value was considerably high in M1 (0, 77) and M2(0.86), while it was much lower in M3(0.51).
The variance components were calculated using Wearden's model, being genetic variance as 80%, environmental variance 20% and maternal effect 0% in M1 and M2. In M3, genetic variance was much lower (26%), and maternal effect variance and environmental variance were higher (40% and 34%, respectively), than those in M1 and M2.
3. There is observed no definite trend in the correlation between molar size and one-week weight, while the correlation between molar size and three-week weight is in the order M1<M2_??_M3.
4. The size of the last developing tooth, M3, is most significantly influenced among three molars by environmental factors including the maternal effect on intra-uterine growth and milk yield.
5. The third molar was missing in some individuals of the A and CBA inbred strains and youngs of CBA_??_×A_??_ cross. In these strains, the third molar, if present, is much smaller and more variable in size, and relative size of M3 to M1 and M2 is remarkably smaller than those in C57BL strain.
6. Heritability of the size of the mandible was estimated by the same procedure as in the molars. The value showed a trend to increase with age.
7. The phenomena clarified in this study, i.e. the degree of the genotypic effect, the maternal effect and the environmental effect change with age, were discussed referring to Monteiro-Falconer's study (1966).

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