All issues
Volume 20 (1976)
- Issue 4 Pages 173-
- Issue 3 Pages 125-
- Issue 2 Pages 51-
- Issue 1 Pages 1-
Volume 20, Issue 4
Displaying 1-9 of 9 articles from this issue
- |<
- <
- 1
- >
- >|
-
Fukusaburo TANAKA1976 Volume 20 Issue 4 Pages 173-176
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSIt is very difficult to discriminate black-wedged and pecky rice grains from healthy unhulled ones. Detection of these infested grains is generally made in hulled rices. However, this method is time-consuming and laborious. In the present experiment, the author attempted to develop a simple and rapid discriminating method of these infested grains and found that when unhulled rice grains were soaked in water for 20∼24 hours, both of the black-wedged and pecky grains could be easily distinguished in a semitransparent white plastic container placed on a light. The results of discrimination were dependent on the water temperature; a high temperature more than 30°C gave a poor result, but constant or varying temperatures in the range from 5° to 25°C gave a satisfactory one. Accelerated water absorption of rice grains in a vacuum chamber may provide a prompt detection of infested grains when required.View full abstractDownload PDF (1828K) -
Yoshito SUZUKI, Katsuyuki YAMAGUCHI, Mikio IGA, Yoshimi HIROSE, Hiroyu ...1976 Volume 20 Issue 4 Pages 177-183
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSSequential data taken on frequency counts of the eggs of Papilio xuthus LINNÉ per tree in a citrus grove were analyzed by the *m-m method (IWAO, 1968) and the process generating the distribution was examined on the basis of field observations on the oviposition behavior of butterflies. The distribution was always contagious and characterised by the values of two parameters, α>0 and β>1 of the *m-m regression. The former value indicated the tendency of a gravid female to diposit a few eggs to a tree per her visit. The latter value reflected the heterogenous conditions among trees. The heterogeneity was partly caused by the variability in the quantity of new leaves from tree to tree. The higher the square value of c.v. in the number of new leaves per tree was, the larger the value of β in the spring sprouting stage became. In the summer and autumn sprouting stages, however, no correlation was observed between the two values. The presence of already-hardened leaves is suggested to uniform the tree conditions in these stages. Spatial distribution of the eggs of P. xuthus in a larger citrus grove is discussed in relation to the possible mechanisms inducing contagiousness.View full abstractDownload PDF (918K) -
Toshio OKU, Juro KOYAMA1976 Volume 20 Issue 4 Pages 184-190
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSIn 1969 the early summer injury of the oriental armyworm, Mythimna separata WALKER, was negligible in Tohoku district, with the exception of a localized infestation on a pasture land, while the next generation insects caused severe damage to rice plants and a few other graminaceous crops extensively over the district in the late summer. It seems difficult to explain this extraordinary increase of the armyworm populations merely by the mutiplication of endemic populations. Examination of synoptic weather maps and wind records from the district during the critical oviposition period of the armyworm indicated that the moth immigration borne on a westerly wind was possible when an atomospheric depression rapidly moved from Kirin province of North China to northern Japan across the Japan Sea in late July. The supposition that the moth immigration occurred on this occasion was supported by baittrap catches of the adults in two localities. Distribution of the outbreak areas suggested that some of the immigrant moth-swarms invaded the eastern provinces across the lower parts of the central mountain-range.View full abstractDownload PDF (984K) -
Yoshiaki KONO, Michihiko SAKAI, Shigeo MORIYA1976 Volume 20 Issue 4 Pages 191-197
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThis study was conducted to examine the action of cartap controlling the infection of rice dwarf disease with special references to the treatment of seedlings in nursery trays prior to the mechanical transplanting. The viruliferous leafhoppers were caged on rice seedlings in nursery trays which had been soaked over night in aqueous solutions of cartap hydrochloride. The treatment with 15ppm reduced the infection to 1/8 of the untreatment. In the treatment with 50ppm, the infection was suppressed almost completely. In these tests about 80% of the insects were poisoned until 6hr following the release. In the transplanted seedlings treated with the 20-ppm cartap solution in the nursery trays, the infection was reduced to 50% of the untreatment, though the rates of heavily poisoned insects did not exceed 15% during 24hr. The probing frequency on the plants decreased even in the insects showing no appearance of the intoxication. Results of other experiments using artificial membranes also supported the effect on the probing activity. It is concluded that the rapid lethal action of cartap and the depressive effect on the transmitting behavior of the leafhopper at sublethal doses account for the reduction of the rice dwarf disease.View full abstractDownload PDF (903K) -
Shigeo MORIYA, Yoichi MAEDA1976 Volume 20 Issue 4 Pages 198-202
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSThe fates of 2-sec-butylphenyl methylcarbamate (carbonyl-14C) [BPMC] and o-cumenyl methylcarbamate (carbonyl-14C) [MIPC] were studied on and in green rice leafhopper. Two strains of the hoppers of different susceptibilities to the carbamate insecticides were used in the present study: Chikugo strain showing the LD50 values of 26.8 (BPMC) and 20.0 (MIPC), and Shinwa strain showing 105.7 and 104.8, respectively. Acetone solution of the 14C-ladelled carbamate was applied topically on the thoracic region of adult females. A rather high rate of penetration was observed, which suggested to be a factor on the fast-acting property of phenyl methycarbamate to the hoppers. The penetration rate, however, showed no difference between Chikugo and Shinwa strains. More than 97% of radioactivity soluble in the organic solvent was due to the intact compound, and its TLC showed little difference between the strains. The concentration of BPMC or MIPC in a whole insect body, calculated from the detected amount, corresponded with I50 value to ChE activity in a susceptible strain of the hoppers. Radioactivity in the water-soluble and unextractable fraction was higher in Chikugo strain in Shinwa strain. It suggest therefore that different metabolism of these methylcarbamates occur between two strains.View full abstractDownload PDF (564K) -
Mitsuo OYAMA1976 Volume 20 Issue 4 Pages 203-207
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSMating and flying abilities of the wild males of Spodoptera litura captured in sex-pheromone traps of dry type were compared with those of the males reared in the laboratory. Mean mating times of the wild- and laboratory-reared males were 6.3±3.7 and 6.8±4.4, respectively, under laboratory conditions. The flying abilities of male moths were examined by recording the durations of flight of the tethered individuals. There was no significant difference between their continuous flying periods, but the wild moths were more active. The recapture rate of the wild males by sex-pheromone traps was significantly higher (33.8%) than that of the laboratory-reared males (5.3%). This difference was increased at the lower temperature. The longevities of wild- and laboratory-reared males were 10.0±7.0 and 17.0±8.2 days, respectively.View full abstractDownload PDF (628K) -
Masaaki YUKINARI1976 Volume 20 Issue 4 Pages 208-211
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESS -
II. Effect of insecticide spray on the growth pattern of aphid population in the glasshouseTetsuo SAITO, Nobuo OGURA, Syun'iti IWAO, Tadashi MIYATA, Hachiro HOND ...1976 Volume 20 Issue 4 Pages 211-212
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSDownload PDF (210K) -
Hideo YAMADA, Tatsuo KOSHIHARA1976 Volume 20 Issue 4 Pages 213-214
Published: December 25, 1976
Released on J-STAGE: February 12, 2009
JOURNAL FREE ACCESSDownload PDF (266K)
- |<
- <
- 1
- >
- >|