All issues
Volume 22 (1957)
- Issue 4-5 Pages 169-
- Issue 3 Pages 113-
- Issue 2 Pages 65-
- Issue 1 Pages 1-
Volume 22, Issue 3
Displaying 1-13 of 13 articles from this issue
- |<
- <
- 1
- >
- >|
-
Shigeyasu AKAI, Haruka TERASAWA1957 Volume 22 Issue 3 Pages 113-118
Published: 1957
Released on J-STAGE: March 08, 2010
JOURNAL FREE ACCESSIn the present paper, the writers describe the results of the experiments on the varietal difference of the resistance of cucumber to the anthracnose disease. Cucurbita moschata and C. maxima were also used in comparison. 1. The inoculation experiments on mature leaves proved that all the varieties of cucumber used were invaded by the causal fungus. The squashes, however, were not affected by the present disease. Judging from the number of lesions in unit area of the inoculated lea-(_??__??__??__??_), Sekino No. 2(_??__??2??_), Sakata-Pickle, Taiwan-Kema(_??__??__??__??_)and wild cucumber were comparatively resistant, and Su-Yo(_??__??_), Kachu-Zairai(_??__??__??__??_), Nisshi-Aonaga(_??__??__??__??_), and San-To(_??__??_)were susceptible, showing 10-15 times more spots than the former. 2. The varietal difference in the susceptibility was recognized also by inoculating spores on cotyledons. In this case the significant difference was not deteced more clearly than in mature leaves. The cotyledons of Shirokikuza, a variety of C. moschata, was also affected. Mature leaves in this variety. however, were not attacked completely. 3. The degree of developing area of spots in leaves was hardly recognized between the cucumber varieties used. 4. In the expressed sap of cotyledons of every variety the conidia germination was accelerated, and the hyphae entered into the epidermal cells developed well in every variety. In these host tissues any different rea-ction accompaning the necrosis and discoloration of cells was not observed, only showed at first a water-soaked appearance of the spot. From these results, all the cells of the cucumber varieties used may be in a strongly susceptible condition to the anthracnose. 5. The conidia of the causal fungus germinated well in water drops gathered from the surface of cotyledons, showing no difference between the varieties. On the cotyledons of squash the germination and the appressoria formation of conidia were also recognized. 6. The degree of penetrating hypha formation from the appressoria, formed on cotyle-dons of cucumcer, differed significantly among the varieties. Between the degree of penetrating hypha formation and the number of spots per unit area there is a high correlation. This presumably accounts for the difference in the susceptibility of cucumber varieties, and the susceptibility may be attributed to the resistance to the invasion of epidermis.View full abstractDownload PDF (450K) -
H. YASUMORI1957 Volume 22 Issue 3 Pages 119-122
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSThis paper deals with the result of the anatomical investigation on the infection of the anthracnose to cucumber leaves. The resistant and susceptible varieties, Taiwan-Kema and Suyo, were used. On leaves of both varieties. appressoria were formed equally in abundance within 24 hours after the inoculation. In the materials fixed and cut 48 hours after the inoculation, the penetration tube arising from an appressorium was commonly visible, and forced its way into the radial wall of the epidermal cells dissolving the middle lamella. The tip of the penetration tube usually swelled again after it had completed the penetration of the cellulosic wall into the epidermal cell. The chloroplasts of the invaded host cells of both the varieties were collapsed and stained deeply with eosin, when leaves were fixed 94 hours after the inoculation. The macroscopic lesions were formed apparently on leaves 5 days after the inoculation and the invaded host cells collapsed entirely. On both varieties, there was no difference in the thickness of cuticule of leaves and in the morphology of the epidermal cells. The susceptibility in both varieties increased in wounded leaves showing several times the spot number of sound leaves. However, the difference in the spot number between sound and wounded leaves, was equal on both the varieties used. This shows that the wounding gives only a similar number of path ways of the causal fungus to both varieties, and does not remove all the obstacles which resist the pathogenic invasion morphologically.View full abstractDownload PDF (1769K) -
Part I. On the oospore germination and the infection to rice seedlings by the oospore.Satoru TAKATSU, Aki TOYAMA1957 Volume 22 Issue 3 Pages 123-128
Published: 1957
Released on J-STAGE: March 08, 2010
JOURNAL FREE ACCESS1. In the present paper the writers deal with the results of a study on the oospore germination of Sclerophthora macrospora (Sacc.) Thirum., Shaw et Naras., the causal fungus of downy mildew of rice plant, and inoculation tests by oospores. 2. When the infected leaves were kept on soil flooded with water in autumn, the oospores became germinable at the end of January, and remained viable at least until May. The percentage of germination ranged from 4.08 to 0.14 during January to May. However, oospores of the infected leaves left on dry soil showed no germination. If the infected leaves were burried 2cm deep in the soil, slight germination of oosporores was obtained irrespective of the water condition in soil. 3. Germinability of the oospores was noticed after about 2 months when the infected leaves were kept on soil with flooded water in early March, May, and at the end of August, respectively. The mature oospores in the rotted leaves can germinate within 48 hours in distilled water. 4. Crushing of rotted leaves is not a necessary measure for the germination of the oospores with high germinability. 5. Distilled water may be a favorable medium for oospore germination. Soil extract did not promote germination. Tap water used seems to check the germination. Addition of 5×10-2-10-3 percent peptone in distilled water inhibited the germination. 2% sucrose solution rather accelerated the germination, but it retarded slightly the formation of zoosporangia at the tip of germ tubes. 6. The optimum temperature for the oospore germination seemed to lie between 18-20°C, the highest 25-26°C, and the minimum somewhat lower than 10-12°C. 7. In inoculation experiments to rice seedlings using oospores, a consideraby high perce-ntage of the disease incidence may sometimes be obtained. 8. Owing to the present results, the writers consider the oospores to be fairly important infection source to wild grasses in autumn and to the rice seedlings in the nursery stage.View full abstractDownload PDF (1261K) -
VII. Growth of intracellular hyphae of Phytophthora infestans in the living potato plant cells which are resistant or susceptible to the infection of them.Kohei TOMIYAMA1957 Volume 22 Issue 3 Pages 129-133
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSIn the previous paper, it was shown by means of vital staining that the majority of the intracellular hyphae of Phytophthora infestans in cells of a resistant potato variety were still living at an early stage of necrosis of host cell. The present experiments have been carried out, in order to ascertain, furthermore, whether the growth of intracellular hyphae is inhibited or not, before the hyper-sensitive death of host cell. A petiole of potato leaf was cut longitudinally with a razor, and washed with strearning water in order to eliminate the contents of destroyed cells. The cut surface of the petioles, almost all the cells of which were living, was inoculated with P. infestans. Four and 6 hours after inoculation, microscopical sections of the inoculated materials were prepared and fixed with Bouin or Formalin-acetic-alcohol, and then the length of intracellular hyphae was measured with a micrometer. As the hypersensitive death of the host cells, caused by infection with the incompatible race of P. infestans, occurs about 10-15 hours after inoculation, the values thus obtained may indicate the growth rate of the fungus in living cells. In the materials used in the present experiments, penetration took place about 2-2.5 hours after inoculation. The varieties tested were Irish Cobbler (r), Hokdai No. 10 (R1), Hokkai No. 17 (R4), 48005-46 (R4) and 41089-8 (R1R4). These varieties were inoculated with compatible or incompatible races of P. infestans: race 0, race 1, race 4 and race 1, 4. The results obtained are as follows. The differences in the growth rate of the hyphae in the living cells is statistically highly significant between races, but not between varieties. The interaction between varieties and races is not statistically significant. From these results, it may be concluded that, even when the host plant cells show resistance to infection by P. infestans owing to presence of resistant genes R1 and R4, the growth of intracellular hyphae of the pathogen is not inhibited, at least, within about 4 hours after penetration. From the accumulated knowledge in this respect, it seems that the most evident cytological phenomenon having close connection with late blight resistance is the time elapsed from penetration of the fungus to the hyper-sensitive death of a host cell.View full abstractDownload PDF (291K) -
Tadao SHIMIZU1957 Volume 22 Issue 3 Pages 133
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSDownload PDF (74K) -
Part 9. On the physiological properties of amylase (I).Ryutaro SAKAI1957 Volume 22 Issue 3 Pages 134-138
Published: 1957
Released on J-STAGE: March 08, 2010
JOURNAL FREE ACCESSThe purpose of the present experiment is to make clear the physiological properties of amylase of Phytophthora infestans. The stock culture H1 (RaceO) employed in the present investigation is the common race which was isolated from naturally-infected leaves of the variety Irish Cobbler at the Hokkaido National Agricultural Experiment Station. The base medium for the experiments was of the following composition, in gm/l: asparagine, 1. 3; KH2PO4, 0.5; K2HPO4, 0.5; MgSO4·7H2O, 0.5; CaCl2·2H2O, 0.5; glucose, 30.0; FeCl3, 0.001; and thiamine, 0.1ppm. The amylase formation of the fungus has been recognized both in the mycelium and in the culture filtrate, but its activity was weak. The optimum hydrogen-ion concentration for saccharogenic and dextriogenic activities of the enzyme was approximately pH 6.0-7.0 and the optimum temperature seems to lie at 40°C. Saccharogenic and dextriogenic activities of the enzyme in the mycelium were inactivated by heating the mycelial extract at pH 7.0 at 70°Cfor 15 minutes. On the other hand, when the extract of the mycelium was acidified to pH 3.5, held at 40°C for 15 minutes, and neutralized, the dextriogenic activity was almost inactivated, while saccharogenic activity remained in a small degree. From the above results, the writer concludes that the amylase of P. infestans is composed chiefly of α-amylase and contains a small amount of saccharifying enzyme.View full abstractDownload PDF (351K) -
Yukiharu KASHIHARA, Zyun HIDAKA1957 Volume 22 Issue 3 Pages 139-142
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSThe writers studied the effects of tobacco mosaic virus on the yield and quality of tobacco through the different stages of plant growth during the years of 1949, 1950 and 1952. As observed in the different plot of inoculation effected on the day of transplanting, on the 15-th day after transplanting, on the 30th day after transplanting, and the plot of non-inoculation with the virus, the virus registered a reduction of 42%, 38%, 32%, and 10% on the yield and reduction of 61%, 62%, 37% and 15 % in quality when expressed as damage for unit, this reduction represent 77%, 76%, 57%, and 22%, respectively. The difference in the severity of damage between the plot of inoculation on the day of transplanting and that of 15 days after, the yield and quality of tobacco were found to be very adversely affected by the disease, especially when the infection took place soon after transplanting. The virus affects can, therefore, be roughly measured by the plant growth stage at the time of virus infection.View full abstractDownload PDF (989K) -
X.-The Detection of the Plant Hormone.Tatsuo WATANABE1957 Volume 22 Issue 3 Pages 143-147
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESS1. The present paper deals with the results of the experiments which were made to ascertain the existence of plant hormone in dry vaccine B of the rice blast fungus (Piricularia oryzae Cavara 2. The writer used the various kind of cocentration of dry vaccine B as the test solution, and distilled water, 2, 4-D, MCP as the control. The writer could ascertain the existence of minute quantity of the plant hormone in 0.5 % dry vaccine B of the rice blast fungus by Went's Pea Test Method. 3. The existence of the plant hormone (see Fig. 1, 2) was ascertained in the chloroform and ether extracted juice of dry vaccine B by Went's Pea Test Method. 4. The existence of the plant hormone in dry vaccine B was ascertained by the sand culture method (contained dry vaccine B), through the growth ratio (see Table 1) in the length of roots and stems of radishes and up land rice plants, especially, through the abnormal growth (hypertrophy, see Fig. 3 or constricted) of radishes. 5. The paper chromatograph method was used to detect the kinds of plant hormone and it was found out something resembling to β-indol acetic acid (see Table 2, 3). 6. Such plant hormone might be produced by the metabolism of rice blast fungus itself. In case the ricc seed is treated with dry vaccine B, it may be absorbed in the seed and stimulate the cells of embryonal tissues of it. It is presumable that this stimulus has made good effects on the germination of the seeds, and afterward, on the growth, the yield and the percentage of diseases.View full abstractDownload PDF (994K) -
Masaki YAMAMOTO1957 Volume 22 Issue 3 Pages 148-152
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSThe examinations of the living potato leaf midribs at the initial period of infection by Phytophthora infestans by means of phase-contrast and polarization microscopes has made clear the following facts: Under phase-contrast microscope, in early stage of the penetration of the pathogen, the resistant variety shows the occurrence of the protoplasmic strands and the acceleration of the protoplasmic current of the infected cells. The migration of nuclei towards the infected parts was recognized both in resistant and in susceptible varieties. The birefringence in the surrounding parts of the diseased spots in the resistant varieties was recognized apparently under polarization microscope. The double refraction was intensified by the treatment with alcohol and was weakened through the strong dehydration by concentrated glycerin and became weak or retarded by the treatment with 4×10-4M DNP solution. From these results, the writer supposed that the stimulation of energy cycle might be concerned with the acceleration of the protoplasmic movement and the appearance of protoplasmic currents of the infected cells of the highly resistant variety. The possibility of the change of micellar structure within protoplasm by the invasion of pathogen in the resistant varieties was also suggested.View full abstractDownload PDF (2822K) -
3. Auxin formation on the culture grown Exobasidium, Taphrina and Ustilago spp.Shoichi HIRATA1957 Volume 22 Issue 3 Pages 153-158
Published: 1957
Released on J-STAGE: March 08, 2010
JOURNAL FREE ACCESSIn the previous reports the present writer stated that the free-auxin in the tissues of abnormal galls, tumors and blisters caused by Protomyces, Albugo, Exobasidium, rust and sumt fungi was contained in much quantity compared with that of the healthy tissues, and reported on the condition of free-auxin in the tissue and also on the auxin formation in the tissue of Brassica napus infested with Albugo candida. The present article deals with experimental studies on the auxin formation by using the cultures of 15 species of Exobasidium, 5 species of Taphrina and 8 species of Ustilago as indicated in Table 1. The results obtained are summarized as follows. The material fungi were all cultured for 15 -30 days at 23°C. The filtrates of liquid media in which the fungi were grown were concentrated to one tenths at 40°C., and 10 agar pieces of 1×2×2mm. in size were immersed into the filtrates. On the other hand an agar block of 10×6×8mm. in size was cut off from the bottom of the solid culture medium in the test tube, and the contained auxin was made to diffuse on an agar plate (1×6×8mm.) by putting the block upright on it. The quantity of the auxin contained in these materials was measured by applying the Went's Avena-coleoptile method. The experimental results on the auxin formation of the organisms on sucrose-potato medium are given in Table 2. When they were cultured for 15 days on liquid media, they produced larger quantity of auxin than those cultured for 30 days, and the latter frequently showed plus-curvature in the case of Avena-coleoptile test. When the culture was done for 15 days on Czapek's medium containing KNO3 as nitrogen source for the nutriment, several fungi slightly produced auxin as shown in Table 3, and the filtrates of these cultures sometimes slightly showed Gordon and Weber's IAA color reaction, but the growth rate and the auxin formation of the fungi were much less than those in the case of the potato media. The growth rate of the fungi on Czapek's media containing L-tryptophane in substitution for KNO3 was much better than those in the cases of the media described above, and showed deep brown color. In this case every fungi produced auxin in much quantity as shown in Table 3, and the concentrated filtrates positively showed Gordon and Weber's IAA reaction, especially in the cases of the media on which gall- or tumor-fungi were cultured. This fact seems to the writer that these fungi have the ability of producing indole acetic acid. Wolf already demonstrated that Exobasidium gracile and Ustilago zeae produced indol acetic acid on L-tryptophane media. The similar results were also obtained by the writer. On the Czapek's medium containing KNO3, however, several fungi produced auxin in some quantity, and this data was shown to be contrary to the result obtained by Wolf. In the present experiments of the writer it was shown that Ustilago nuda and U. tritici produced auxin in large quantity, and this fact may give some hint on the physiology of parasitism of these fungi.View full abstractDownload PDF (345K) -
Satoshi WAKIMOTO1957 Volume 22 Issue 3 Pages 159-163
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSA simple method for the comparison of bacterial populations from a large number of samples using the host-specific bacteriophage was described. Xanthomouas oryzae No. 60 and its specific phage were used for this purpose. Samples of bacteria are suspended in Ca Vf Ch medium or potato semi-synthetic medium, and added with phage suspensions to make the final concentration of 103-5 per ml. The samples were then incubated under optimum temperatures and under shaking at 80 rpm to propagate the added phage. Three hours later, aliquots were pipetted out from the centrifuged (6000 rpm, 5min.) supernatant and plated with the indicator strain of bacteria, to make plaque countings. It was confirmed that the number of plaques are usually proportional to the number of bacteia initially contained in the sample. This method will be favorably applied for studies on plant resistance against bacterial diseases, effects of bacteriocides, and other subjects, where problems may be dissolved on the basis of bacterial number contained in the plant tissues.View full abstractDownload PDF (391K) -
Yoshito IWATA1957 Volume 22 Issue 3 Pages 164-165
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSThe author collected two kinds of fungi attacking leaves of Aspidistra elatior at Tokyo in 1938. The one was referable to Phyllosticta Aspidistrae Oud., and the other, which produced minute brown spots 1-3mm in diameter, was considered as an undescribed species and the name Macrophoma Aspidistrae n. sp. was assigned to it. The diagnosis is as follows. Macrophoma Aspidistrae Iwata, n. sp. Maculis minutis, rotundatis vel angularibus niternervies, avellaneis centro, fuscis margine, 1-3mm diam. Pycnidiis hypophyllis vel epiphyllis, 1-compluribus in 1 macula, globosis, 60-120μ diam. hypodermicis, cum hiato, quo 15 -30μ magno. Pycnosporiso vatis vel ellipticis, hyalinis, continuis, oleosis, 11-20×6.5-12.5u. Hab. in foliis vivis Aspidistrae elatioris, Tokyo, Japonia (Nov. 21, 1938, Y. Iwata). The type specimen is deposited in the herbarium of National Institute of Agricultural Sciences, Tokyo, Japan.View full abstractDownload PDF (1384K) -
Kenzo SAWAMURA1957 Volume 22 Issue 3 Pages 166-167
Published: 1957
Released on J-STAGE: April 21, 2009
JOURNAL FREE ACCESSSince 1953, a powdery mildew has been observed on the leaves of cabbage plants (Brassica oleracea var. capitata) and mustard (B. juncea) in the greenhouse and gardens at Fujisaki-cho, Aomori, and on rape (B. napus) in the greenhouse at Sapporo, Hokkaido. By inoculation experiments the conidia from cabbage proved to infect these two species of plants (cabbage, rape), but not cauliflower, Japanese radish, tobacco and peas. The mildew found on Japanese radish, rape and Cardamine flexuosa in Japan is reported by Homma (1933) as Erysiphe cichoracearum DC. The present fungus, though its perithecial stage is not yet observed, seems to be identified as E. polygoni DC. Measurements of size and shape of conidia produced on cabbage and the solitary formation of them on conidiophores agree well with Davis' descriptions concerning E. polygoni on Chinese cabbage in U.S.A (1928). The shape of germ tubes of conidia also belongs to the polygoni type (Hirata, 1942, '55).View full abstractDownload PDF (821K)
- |<
- <
- 1
- >
- >|