Seedlings of 47 varieties or strains of 16 species of'Triticum, 44 varieties or strains of 19 species of Aegilops, 23 varieties or strains of 6 species of Hordeum, one strain of Hc, ynaldia villQsa, one strain of Avena sativa and 4 selections of Aegilotricum were tested with Puccinia graminis f. sp. Tritici 11. The experimental results are summarized as follows : 1. Among species of Einkorn group of Triticum, three strains, of Triticum monococcum and one strain of T. aegilopoides var. boeticum were susceptible to Puccinia grc, ninis f. sp. Tritici 11, but one strain of Triiicum monococcum (early) was resistant to it. Eight species of Emmer group : Triticum dicoccoides, T. dicoccwa, T. durum, T. turgidum. T. polonicwa, T. persicum, T. pycmidale and T. orienta:le were su:sceptible. Three strains of T'riticum Timopheevi belonging to Timopheevi group weire highly resistant, but one strain of this species was moderately resistant. Five species of Dinkel group : Triticum Spelta, T. vulgare, T. conlrpactum, T. sphaerococcum and T. Macha were susceptible, exc, ept one strain of Triticum vulg ?? e var. graecmn and 2 strains of T. vulgL2;re(Timstein).

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1. This work is one of the studies in which the writers intend to make clear the mode of quantitative inheritance in main crops from the view ppint of breeding. Materials used are the same as those used for the studies of inheritance of the panicle length and culm height in the preceding experiments(SYAKUDO, et. al. 1952-a, b) namely -, the F₁-F₄ generations from the hybnds of "NABESIMA" and "KAlRYO-AIKOKIJHEN-DAIKOKUGATA", which were crossed in 1945 at the plant-breeding laboratory of the Kyoto Univ. The total numbers of lines and individuals ob, served are 467 and 49, 223 respectively. 2, , NABESIMA" is a normal variety showing a medium length of panicles and a medium height of culm with small grains, three dimensions of which are about 5.3mm, 3.0 mm, and 2.1 mm. "KAIRYO-AIKOKUHEN-DAIKOKUGATA" is a dwarfish variety with short panicles, short culm and small round grains, three dimensions of which being 4.5 mm, 3.2 mm and 2.3 mm. 3. The conditions of cultivation and the methods, of investigation are the same as those already, described in the writer's reports (SYAKUDO, 1948-b, 1951). . 4. The progeny test in regard to the grain length was made considering the mean value, standard deviatian, coefiicient of variabilityand the range of variance. The results show that the gene Gr3 and the dwarfish gene D1 determine the grain length. Thus the genotypes of the parents will be assumed as follows:

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1. In the present investigation the chroirlosomes of 3species of genus Secale viz..S. africanum, S. montauum and S. Vavilovii were examined. . 2. The chromosome number of genus Secale was n=7 and 2n=14. 3. The bivalents at the heterotypic metaphase of PMC-s, were ring-and stick-shaped in the 3 species, the former ones being more frequently observed than the latter. 4. At the heterotypic metaphase of PMC-s S.montanum, 14 bivalents were observed rarely (one tiine in 1000 PMC-s). This case ought tobe due to the duplication of 14 univalents at anearly stage of meiotic division in PMC-s5. At the heterotypic metaphase of PMC-s.., of S. Vavilovii, one of 7 bivalents was occasionaly divided into two elements earlier than the others, so that it was observed as two univalents even in metaphase (Figs. 18, 19).The percentage of occurrence of one bivalents being divided onto two elements to ail the number of PMC-s. ibserved was 8.8percent(18 times in 203 PMCs).

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1. Several morphologicai and physiological characters of triploid varieties were compared with diploids. 2. There was no clear difference on the leaf size and shape between triploids and diploids, but triploid leaves were thicker than those of diploids. As a rule every internal tissue of triploid leaves was thicker than diploids. It is evident that triploid leaves had larger stomatas of which the distribution density vias lower, compared with diploids. 3. No difference between both the plants could be recognized on the res.istance to brown blight total nitrogen and tannin content in suminer, the reduced form vitamin C content in winter, and regeneration power in cutting. Triploid varieties was more hardy to cold, and some of them had extremely early growing spring bud. The water reserving ability of triploid leaves isolated from stem was greater than that of diploids in September, but the relation changed to be indifferent. in December. 4. Generally triploid fertility was very low but the difference of fertility between each triploid variety was noticed. The pollen grains of triploids showed high sterility. 5. From progenies of triploids, we discovered one aneuploid plant (2n=44). The characters were same like those of triploids and the meio. sis was proceeded abnormally. 6. With colchicine treatment to the growing point of germinated seeds, some tetraploid plants (2ri=60) were obtained. At present, tetraploid plants are growing slowly and they have, dwarf form.

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It is already shown that the supply of sugar is necessary to induce the vernalization effects. :Herewith, the authors have carried out an expe riment to know the critical duration of supply wheats by using a winter variety "YOKOZAWA"under the concentratibns of 1% and 3% glucose, respectively. Consequently, it was found that the inducing of vernalizationeffects required more than 6 days m the 1%, 4 days m the 3% respectrvely and if the treatment was less than 2 days, there appeared not sign of vernalization effects. But the evidence did not exist enough to show that the vernalization effects were incereased by elongating the duration of sugar supply. The seeds treated with cold temperature during various lengths of period were kept sudcesively in the same condition without air and the infiuence of absence of oxygen upon the induction of vernalization eifects were examined. In this case there was no sign of vernalization effects as shown already by some workers. But as the seeds subjected to the cold treatment of the critical number of days enough to induce vernalization effects stand in the very unstable condition, and yet, this condition tends to be stabilized easily by elongating the duration of cold treatment, it seems to be necessary to, research'the physiological nature of vernalization in consideration of these points.

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1. Irregular behavior of chromosomes, was not found in the meiosis of sterile hybrids ; sexual organs such as ovary and anther were also anatomically normal. 2. During the development of megaspore in sterile hybrids, deterioration, possibl.y in a larger pairt due to the suppression or failure of nuclear division, was found to occur at various stages covering from the first division of the innermost cell of the tetrad until the maturation of embryosac.At the time of heading, there were found, besides normal embryosacs, several kinds of abnormal ones which were varying from those showing only a trace of embryosac cavity to those containing a number of nuclei. 3. Failure of the development of microspore was found to advance after the "second colo-tracting stage" (according to KIHARA'S nomenclature), possibly with the first and second divisions of pollen nucleus. At the time of heading, pollen grains seemed to be classified into three types as (A) normal pollen containing three nuclei, (B) abnormal pollen containing two nuclei, poor in starch content an-d smaller in diameter, and -(C) innert pollen corl.tail.ing one nucieus and irregular in shape. 4. Considering from the above mentioned facts and other phenomena such that ncrmal pollen percentage depends upon the combination of parental varieties and is not dirferent between reciprocal crosses(as reported in the 2nd article of this series), the degenera.tion of gametes in sterile hybrids seems to be due to certain gene conrbinations which might be 'produced by the recombination in meiosis and carried by those gametes themselves. It was assumed as a working hypothesis that a genetial factor, X, w, hich act within germ cells to maintain the normal development, would be duplicated, and thus intervarietal hybrid Xlx2 xxlX2 would be semi-sterile owingto the degeneration of xlx2 gametes. 5. As a first step of gene analysis, two nearly related varieties, 219 (non-glutinous) and 221 (glutinous), and the third variety, 63 (gluti-nous), among thern 219 x 563 was semi-sterile while 221 x563 and 219x221 were free from sterility, were taken as materials, and variety 563 was crossed with the pdllen of Fl and F2s of219 X 221 .

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1. In order to clarify the crossing technique of Genge (Astragalus stjnicus L. ), some experiments have been carried out on the fertilization and the castration method. 2. Genge is a self or cross fertilizing plant in the field, but the fertilization is almost impossible when the plant being isolated from insects ih the wire cage, notwithstanding the stigma being covered with the self pollen grains at the flowering time. 3. The stigma consists of the papillae and the hairs of two kinds surrounding it. As it is supposed that the inner hairs whicn cover the papillae hinder the contact between pollen grains and the papillae, resulting the fertilization in failure, artificial pollination must be handled so as to stick the pollen grains to the papillae dir-ectly. 4. Genge is a proterandry plant and the anther dehisces before the opening of flower in a floret. The duration of high fertilizing ability of the pollen was in the course from the time of anther dehiscence - the previous day of fiower opening -to 3 days after flowering, but that of the stigma was from the opening time to 4 days after then. 5. Three castration methods, viz. stamenspicking before the anther dehiscence, killing of the self pollinated pollen grains by 50% alcohol, and excision of the self pollinated stigma with the petals (keels) and stamens after dehiscence or flowering were compared. As the results, the stamens-picking method shows the highest percentage in fertilization and in such a case that the castration and the pollination must be performed simultaneously it can be accomplished by the use of 50% alcohol method.

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1. It has been assumed by Japanese rice breeders that it is very hard or almost impossible to obtain superior varieties from, highly sterile intersubspeciflc hybrid(japonica X indica) for their high sterility a, nd complicate segregating behaviors. 2. In this report the writers present one example of obtaining some fertile constant new lines of rice from such highly sterile intersubspecific hybrid by bulk method. 3. The F₁ between Murasakimuyozetsuto-japonica type, liguleless, short-grained, non-glutinous, long-awned variety and Koiketsu mochi. indica type, long grained, glutinous, awnless, variety-showed highly vigorous growth habit, but set only 23% fertile grain. 4. The progenies of these F₁ plants were reared in bulk ori the relatively small area less than 1/20 acre from F₂ to F₆ geheration. 5. 45 plants were selected in F₆ population and tested their segregating behavior in F₇ and F₈ generations by pedigree culture. 6. Two families and two single lines were determined to be new constant lines and some characters of these lines such as culm length, ear length, panicle number per plant, fertility, length and breadth of unhulled grain, grain, shape, and endosperm character wre tabulated i.n table 1, 2 and 3, with those of their parents and' F₁ plants. 7. The writers briefiy discussed on the problem of utilization of such sterile intersubspecific hybrid for future rice breeding.

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1. The effect of selections about the course of breeding of the Varieties, CHUGOKU No. 79, N0.80, that were bred by combined. methods of bulk and pedigree was studied. 2. Selections for yellow and green mosaic were cafried by bulk method on the F₂, F₃, F₄ of hybrids progenies to each othe regions, and recognized the effect of selections. 3. Other important charactors were selected by pedigree method after F₅.4. The effects of selections to the time of earing, maturity, resistance to green and yellow mosaic and straw strength were evident, btit the effects of selections to the numbers of ears were not e'ffective. 5. As for the yielding abilities, selections were. made about the numbers of spikelets and fiowers, types of plant in early pedigree generations and the effects of selections were recognized. 6. Two superior varieties were bred with this method, these varieties are not also strong to green and yellow mosaic, but also strong to scab, strong straw, early mattirity and high yeild fit to project.

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The buckwheat is gener, ally a self-sterile plant. However, a few self-fertile plairts are occasionally found in the populations. In the selffertile, Iong-styled plants, pollen grains are much larger than those of normal long-styled l;)lants and are nearly as large as those of shortstyled plants. The stigmas of the self-fertile, long-styled plants are sotnewhat smaller than thos.e of normal long-styled plants. It seems probable that the high self-fertility of the selffertile, long-styled plants is chiefiy due to the large pollen gr, ains. Both plants having large pollen grains only in the anthers and plants havirig large and small pollen grains in varying proportions are iound in the self-fertile, Iongstyled plants. The self-fertility, of the self-fertle, Iohg-styled plants is inherited in the later generations.

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