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Volume 32 (1966)
- Issue 5 Pages 251-
- Issue 4 Pages 175-
- Issue 3 Pages 109-
- Issue 2 Pages 63-
- Issue 1 Pages 1-
Volume 32, Issue 1
Displaying 1-10 of 10 articles from this issue
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(XV) Recovery from disease due to low temperature in winterYasuo TAHAMA1966 Volume 32 Issue 1 Pages 1-4
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSAs has previously been reported, the mulberry dwarf virus is inactivated or decreases in the affected shoots at temperatures below 15°C during winter, but is not at temperatures above 20°C, whereas in the roots the virus does not decrease even at low temperatures. It was attempted to obtain further information on the cause of recovery of the disease.
Cuttings obtained from diseased plants of Morus alba L. var. Ichinose which had been kept at low temperatures (3°C or natural low temperatures in winter) from November or December to April or May, when grown in a greenhouse, mostly recovered from the disease, whereas diseased cuttings obtained from similarly treated plants of Okinawaguwa (local name of Shimaguwa), Morus australis Poiret, all developed diseased shoots as those kept at higher temperatures (Table 1).
Diseased trees of Morus latifolia Poiret var. Shirome-roso were kept at 3°C from May to June (for 1 month), to July (for 2 months), to August (for 3 months), and to September (for 4 months). When these trees were transferred to a chamber at 30°C, they all developed symptoms on new growth (Table 2). The cuttings obtained from diseased potted trees of Morus alba L. var. Ichinose and Morus latifolia Poiret var. Shirome-roso which had been kept in a chamber at 3°C from July to November, when grown in a greenhouse, all developed diseased shoots in the same way as those kept at natural high temperatures (Table 3).
It is likely that the inactivation of the virus in the shoots was caused by the low temperature and by the dormancy of mulberry tree in winter. Okinawaguwa which did not recover from the disease is an evergreen tree, whereas Morus alba L. var. Ichinose and Morus latifoleia Poiret var. Shirome-roso which recovered in winter are both deciduous trees.View full abstractDownload PDF (918K) -
Yukihisa TANAKA, Hikaru TAGAWA, Keichi TOMARU1966 Volume 32 Issue 1 Pages 5-9
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSMethod for labeling bacteria with radioactive phosphorus (32P) was studied using Pseudomonas solanacearum E.F. Smith, the causal agent of tobacco wilt disease.
Potato sucrose liquid medium (PS) and bouillon medium (B), both added with 1μc/ml of 32P, were compared each other as to the bacterial growth and the uptake of 32P by the bacteria.
The PS culture medium was found to be more satisfactory for the bacterial growth and the uptake of 32P.
The amount of uptake of 32P by bacteria was markedly reduced by the addition of non-radioactive phosphorus (31P) to the PS medium.
The amount of 32P uptake per bacterial cell was less in the higher bacterial concentration of inoculum (108/ml) than that of the lower one (106/ml) in the PS medium for 5 hours at 30°C. In this experiment, a high degree of efficiency of 32P uptake by total bacteria was obtained in culture containing 107 cells per ml for 48 hours at 30°C.
The increase of the 32P uptake per bacterial cell was followed by the increased quantity of 32P in the medium containing from 10-1μc per ml to 10μc per ml, for 48 hours at 30°C.
Preservation of 32P labeled bacteria in three non-radioactive media (water, culture solution for tobacco and PS medium) was examined at 10°C and 30°C.
Generally, the higher rate of release of 32P from the labeled bacteria was shown in the incubation at 30°C and the lowest released rate was shown in the culture solution for tobacco.
The rate of released 32P from labeled bacteria in the culture solution at 30°C was found as follows: after one day-about 1%, 3 days-about 2%, 5 and 10 days-about 3%.View full abstractDownload PDF (615K) -
Influence of amount of nitrogen and potassium on host entry and infection of Helminthosporium oryzaeOsamu HORINO, Shigeyasu AKAI1966 Volume 32 Issue 1 Pages 10-13
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSIn this communication we dealt with the conidial germination and hyphal invasion of Helminthosporium oryzae on or into the leaves of rice plants raised in sand culture with different nutrient solutions.
About 98 per cent of germinated conidia established their invasion through motor cells and the rest through stomatal pore, and no instances invading through other area were recongnized. After the invasion of infection hyphae into motor cells, abundant granular substances were deposited in the cells.
These granular substances were abundant in the cells of plants raised with excess potassium (8K and 3K) or excess nitrogen (6N) and a few in the cells of plant grown in nitrogen or potassium deficiency (1/4N or 1/4K). This granular degeneration of the cells seemed to be an indicative of plant resistant to the fungus, the deficient plant being susceptible to the fungal infection. Although no morphological difference was observed among the fungal hyphae on the tested plants, the infection hyphae seemed to be little narrower in the motor cells showed high glanular degeneration.View full abstractDownload PDF (515K) -
Takken MATUO, Osamu CHIBA1966 Volume 32 Issue 1 Pages 14-22
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSDamping-off of coniferous seedlings, especially the root-rot type of the disease, is mostly caused by several species of Fusarium. The results of idenification of 106 isolates from diseased roots of nursery stocks at various localities in Japan, including 12 isolates from deciduous trees, showed that about 88 per cent of isolates were F. oxysporum and the rest of them were composed of F. solani, F. roseum, and F. lateritium. From these isolates 13 were selected owing to their higher pathogenicity to coniferous seedlings and were examined for their formae speciales by a series of inoculation experiments. It was made clear that all isolates of F. oxysporum were capable of infecting seedlings of Pinus densiflora, Larix leptolepis, Cryptomeria japonica, and Chamaecyparis obtusa, while they were non-pathogenic to any kinds of indicator plants of the other formae speciales of this species. Moreover, the tests also indicated that a possible difference in virulence existed among the isolates; six of tested isolates were most virulent to L. leptolepis and the rest one was more pathogenic to C. japonica and C. obtusa than L. leptolepis. It may be concluded from these results that the former six isolates are classified as F. oxysporum f. sp. pini race 1 and the remaining one as race 2, respectively.
Two isolates of F. solani were identified as F. solani f. sp. radicicola, which frequently showed variable pathogenicity. There found certain differences in the pathogenicity between the isolates of F. roseum and F. roseum f. sp. cerealis, and also between the isolates of F. lateritium and F. lateritium f. sp. mori as well as f. sp. cerealis, but it was difficult, from their variable pathogenicty, to classified them as new formae speciales of these species.
In general, the occurrence of damping-off of coniferous seedlings depends remarkably upon the environmental factors and it seems that many kinds of Fusaria would be able to become causal agents of the disease under favorable environmental conditions for disease development.View full abstractDownload PDF (1755K) -
Shoichi TANAKA, Kazuyoshi HIROSE1966 Volume 32 Issue 1 Pages 23-25
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSJapanese flowering cherry varieties established at three experimental stations in Japan, were indexed for little cherry virus using the sweet cherry indicator variety, Sam. Of the thirty one flowering cherry varietieties tested, thirteen were positive, one was negative, fourteen could not be observed because of defoliation due to weather conditions and shot hole, and three were incompatible with the Sam buds. Similar indexing tests with some of these varieties in the United States did not fully agree. It is postulated that the little cherry virus is more widely distributed in Japan because of the use of vegetatively propagated rootstocks, as compared to the United States which uses rootstocks grown from seed.View full abstractDownload PDF (276K) -
Nakato NAITO, Toshikazu TANI1966 Volume 32 Issue 1 Pages 26-34
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSWhen sown on the surface of distilled water, uredospores of Puccinia coronata Corda begin to swell and then issue projections out of germ-pores. The present paper mainly deals with observations on these morphological changes during the early stage of germination and also describes some distinguishable points between projections and germ-tubes.
The volume of spores becomes about 2 times in approximately 20 seconds after being floated on water drop. Already at this time spores seem to have been physiologically activated and also to have diluted by intake of water their own components contained in high concentration to such a level as having no inhibitory effect for germination process. The rise of volume continues for 20 minutes to reach the maximum-3.3 times the volume of resting spores, and there is a little shrinkage of the original spore with the onset of germ-tube growth. During 8 to 20 minutes of incubation, spores protrude respectively 1 to 6 small projections of “Dome-type”, which are less than 3μ in length. The appearance of projections in questhon is earlier on the half-sphere of a spore in contact with water than on the opposite one, but in their total number there is no difference between both.
One (rarely two) of the projections of a spore changes from “Dome-type” to “Cylinder-type” in 30 to 50 minutes after the first appearance, and it enters into a continuous growth rapidly. The latter type projection differs from the former one not only in a morphological shape but also in the response to air-drying as well as in the sensibility against chemicals. On the basis of these facts the writers considered that “Cylinder-type” projection alone, the length of which is larger than 3μ, should be regarded as a real germ-tube and that “Dome-type” projection would be an intermediate organ growing into a germ-tube.View full abstractDownload PDF (1946K) -
Osamu CHIBA, Shôzô TAKAI1966 Volume 32 Issue 1 Pages 34-39
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSThree poplar clones, Populus deltoides angulata (resistant), P. deltoides missouriensis (susceptible), and P. “Kamabuchi-1” (variable in susceptibility according to the growing season) were inoculated with uredospores of Melampsora larici-populina, incubated for 9 days, and then cuttings from healthy and infected plants were fed with 14CO2 for 20 hours.
In healthy and rusted leaves of these clones, at least six kinds of sugars, sucrose, glucose, fructose, raffinose (?) and two other unidentified sugars, were detected on the autoradio-chromatograms. The specific radioactivity of each sugar generally increased in rusted leaves with a few exceptions, whereas there were remarkable differences in the increasing degree of specific radioactivity among sugar fractions.
Labeling of sucrose, glucose and fructose with 14C from 14CO2 increased by rust infection, and the degree of the increase was conspicuous in P. deltoides missouriensis, while it was insignificant in P. deltoides angulata. A general increase in both total and specific radio-activity of sucrose may suggest the possibility of stimulated photosynthesis in rusted leaves.
The degree of increase in the specific radioactivity of glucose and fructose were almost equal in rusted leaves of P. deltoides angulata, whereas particular increases were observed for glucose in P. deltoides missouriensis and for fructose in P. “Kamabuchi”, respectively. This fact would suggest that in rusted leaves of the latter two clones the disturbance of carbohydrate metabolism incited by rust infection is still continued, and that there are considerable differences between two clones concerning the pathway of carbohydrate metabolism in infected leaves.View full abstractDownload PDF (1188K) -
Si Chong LEE, Shohei MATSUMOTO1966 Volume 32 Issue 1 Pages 40-45
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESS1. Twenty one isolates of rice blast fungus collected from 4 localities in Korea during 1962 and 1963, were differentiated into ten physiologic races on the basis of the reactions of Japanese 12 differential varieties and additional 2 varieties. These races were named tentatively as a, b, c, d, e, f, g, h1, h2, and h3.
2. Races a, d, and f reacted on the Japanese differentials as the Japanese races T-2, N-3 and T-3 respectively. Besides, both races b and h1, c and h2, and e and h3 reacted on the differentials as the Japanese race N-1, N-2 and N-4 respectively. The rest one, out of the ten, race g was similar in the reactions to that which had been reported, but not yet registered in Japan.
3. On the U.S. differentials, races b, c and d reacted as the U.S. races 6, 2 and 4 respectively. Besides, both races f and h1, and e and h3 reacted as the U.S. races 21 and 18 respectively. While, race a showed different reactions from the races reported by United States workers.
4. It was assumed that the race constitution in Korea was similar to that in Japan, according to the reactions of the tested isolates both on the Japanese and United States differential varieties.View full abstractDownload PDF (686K) -
Mode of stylet insertion and infection site of the virusHazime YOSHII1966 Volume 32 Issue 1 Pages 46-51
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESS1. In the feeding of the green peach aphids on the leaf stalk of turnip plants the stylet was observed inserted intercellularly in the direction of the phloem, leaving stylet track or salivary sheath which frequently has many branches. Judged from the manner in which the sheath was formed, the direction of extension of the stylet after penetration by bending the stylet, was either to the left or right but not to up-or downward.
2. The stylet was inserted to the surface of the host plant in nearly all instances at a point between two epidermal cells; from which position it extended intercellularly.
3. Onion epidermal membrane was used for making observations on the sequence of extention of salivary sheath and how the branches were produced.
4. Some considerations were given on saliva comprising both the one watery and water soluble and the other coagulable which formed salivary sheath. Considerations were also given on the role of salivary sheath as a substitute for rostrum.
5. In the cases of non-persistent viruses such as turnip mosaic virus, transmission of the virus is said to be effective by a short feeding period of from 5 to 20 seconds by the aphids, and it is also said that during this brief period the stylet is hardly capable of penetrating through epidermal layer, and under this circumstance, the virus is likely to have been transmitted to the plasmodesmata in the intercellular region between two epidermal cells. This is supported by the author on the basis of the fact that the virus inhibitor in Chenopodium album had no influence upon the effect of inoculation by the aphids, in contrast to the cases of inoculation by rubbing method.View full abstractDownload PDF (1548K) -
Takao SUZUKI, Ikuo SUMINA1966 Volume 32 Issue 1 Pages 52-57
Published: January 30, 1966
Released on J-STAGE: February 19, 2009
JOURNAL FREE ACCESSSpraying with dihydrostreptomycin (Dsm) has been reported to be effective for control of bacterial leaf blight of rice, incited by Xanthomonas oryzae, but occasionally causes reduction of the grain yield. The present experiment showed that, two or three times applications of Dsm to rice plant, including spray at the stage of flowering, caused reduction in the percentage of grains of standard weight, but not in the number of panicles per plant nor number of spikelets per panicle. It was also indicated that Dsmspray at the flowering stage did not effect fertilization, but caused reduction in average grain weight, suggesting a retarding effect on the ripening process of rice grains. Quantitative analysis was made for sugar and starch in the selected organs of rice plant, sprayed with Dsm (1000ppm) at the flowering stage. It was revealed that contents of total sugar, reducing sugar, and starch in the flag leaf of rice plant sprayed, were equal to those of check. Sugar and starch contents in the sheath and culm of plant subjected to spray with Dsm were greater than those of check. In the grains, however, sugar content of the sprayed plant was much greater, and starch was considerably less, than that of check. Accordingly, the difference in sugar content between flag leaf and grain of Dsm-sprayed plant was considerably small as compared with that of checkplant. It is suggested that Dsm-spray may give an inhibitory effect to translocation of sugar from flag leaf to grain and starch accumulation in grain of rice plant.View full abstractDownload PDF (796K)
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