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41.
T Shimizu T Takahata M Kato 《Nippon juigaku zasshi. The Japanese journal of veterinary science》1990,52(2):191-197
Both Mycoplasma gallisepticum (MG) and M. synoviae (MS) antigens prepared for the routine haemagglutination inhibition (HI) test were diluted and absorbed to the separate pieces of durapore membrane for the measurement of dot-immunobinding (DIB) titers of test sera. Besides, durapore strips bearing both antigens were employed for a DIB test with chicken sera definitely diluted 100-fold. Shortening of reaction time of chicken sera with antigens as well as with the secondary serum markedly eliminated non-specific DIB reactions exhibited at low dilutions although the same condition was not so effective on the elimination of non-specific reactions among rabbit hyperimmune sera. Rapid and specific development of DIB antibody which continued at high titer up to 1:640 for 10 weeks postinoculation was proved in the sera of SPF chickens inoculated with MG or MS, while DIB titers of sera from uninoculated chickens remained 1:20 or lower. Non-specific reactions, which occurred in the routine serum plate agglutination test with a part of sera from the inoculated chickens, were not exhibited in the DIB as well as in the HI test with the same sera. Results of the DIB test with serum samples from 287 conventionally reared chickens definitely diluted 100-fold coincided with the results of HI test at a level of 90% with MG and 89% with MS antigen. This technique seems to be useful for a rapid, simple and specific diagnosis of avian mycoplasmosis. 相似文献
42.
Fifteen lines of Brassica napus were resynthesized via ovule culture through 24 interspecific crosses between four Brassica oleracea and three Brassica campestris accessions. The degree of success in the interspecific crosses was significantly influenced by maternal genotypes. The interspecific hybrid production rate (HPR) varied with combinations from 0 to 76.9%, with a mean HPR of 24.7% for the crosses with B. campestris as the female parent and 6.9% for the crosses with B. oleracea as female parent. Twenty‐four crosses between seven natural and six resynthesized B. napus gave, on average, 10.3 seeds per pod, and ranged from 1.2 to 22.0 seeds per pod, depending on genotypes of both parents. Resynthesized lines of B. napus showed high erucic acid content and variable content of linolenic acid, ranging from 3.4% to 9.9%. The fatty acid composition in hybrid seeds between natural and resynthesized B. napus was dominated by the embryo genotypes; an additive mode was shown for erucic acid and positive over‐dominance for linolenic acid content. 相似文献
43.
Summary Mitochondrial DNA (mtDNA) diversity has been determined in apple landraces and cultivars, based upon restriction fragment length polymorphisms (RFLPs) for several mitochondrial genes. Our analysis includes three cultivars, Golden Delicious, McIntosh and Delicious, which represent the various patterns of mtDNA polymorphisms previously described (Ishikawa et al., 1992). A total of five RFLPs were detected, allowing classification of the apple genotypes into four cytoplasmic groups: GroupI, Golden Delicious-type; GroupII, McIntosh-type; GroupIII, Delicious-type; and Group IV, Dolgo Crab-type. European landraces and cultivars were assigned to Groups I, II, and III, while chinese crab apples were placed in either Group III or IV. 相似文献
44.
The effect of genome composition and cytoplasm on petal colour was studied in Brassica. Three accessions of yellow‐petalled B. rapa (2n= 20, AA) were crossed with a white‐petalled B. oleracea var. alboglabra (2n= 18, CC) and with three cream‐yellow‐petalled B. oleracea var. gongylodes (2n= 18, CC) to produce resynthesized B. napus (2n= 38, AACC or CCAA) and sesquidiploids (2n= 29, AAC or CAA). Petal colour was measured with a Hunter automatic colour difference meter. The results revealed that petal colour in Brassica is controlled by nuclear genes and by cytoplasmic factors. Additive and epistatic gene effects were involved in the action of nuclear genes. When crosses were made between yellow‐petalled B. rapa and white‐petalled B. oleracea var. alboglabra, significant additive, epistatic and cytoplasmic effects were found. White petal colour was partially epistatic over yellow petal colour. When crosses were made between yellow‐petalled B. rapa and cream‐yellow‐petalled B. oleracea var. gongylodes, only epistatic effects were detected. Yellow petal colour was epistatic over cream‐yellow. 相似文献
45.
Simplified culture method of detached ears and its application to vernalization in wheat 总被引:3,自引:0,他引:3
Summary The effects of the addition of sulfurous acid into culture solution and of cold treatment of the solution were examined to simplify the culture of detached wheat ears. In the simplified method, detached ears could be cultured at room temperature on the liquid medium containing 100 g/l sucrose and 0.075% sulfurous acid without any sterilization. The immature seeds in detached ears cultured by this method were treated with low temperature or with chemicals known to have vernalizing effect. The chemical treatment did not affect the chilling requirement of immature embryos, although photoperiodic response and narrow-sense earliness were reduced by kinetin and trypsin. The low temperature treatment drastically affected the chilling requirement, and fully vernalized mature seeds having normal germinability were obtained by treating the detached ears in culture with low temperature from 10 days after anthesis. 相似文献
46.
Summary Nucleus substitution of Brassica japonica (2n=20) with Raphanus sativus (2n=18) was carried out by means of repeated backcrossing of Brassicoraphavus (2n=37) to R. sativus as a pollen donor. In the course of nucleus substitution, chlorophyll deficiency appeared. Plants with more than 28 chromosomes, like their parents, had green leaves and those with 24 to 26 chromosomes had yellowish green ones. Almost all plants with 18 to 23 chromosomes showed yellow or whitish yellow. The R. sativus with B. japonica cytoplasm (2n=18) was obtained after four successive backerosses. The completely substituted R. sativus showed the same fertility as the true R. sativus used as a recurrent parent. It is assumed that the chlorophyll deficiency is caused by disharmony between the B. japonica cytoplasm and the R. sativus nucleus. The chlorophyll deficiency is discussed in comparison with male sterility or other characters which sometimes occur in alloplasmic Raphanus and Brassica species. 相似文献
47.
A method to make the hourglass worm gearing with the property of mismatchedpoint contact has been proposed.The worm and the hob of the worm gearing is generated by a coneand a straight line located on the cone respectively. The basic principle of the worm gearing has beenanalysed. The formulas for calcultating the machining parameters has been obtained. And the toothcontact of the worm gearing has been investigated.The result shows that this worm gearing could getopint contact well. 相似文献
48.
Makiko Chono Hitoshi Matsunaka Masako Seki Masaya Fujita Chikako Kiribuchi-Otobe Shunsuke Oda Hisayo Kojima Shingo Nakamura 《Breeding Science》2015,65(1):103-109
In the wheat (Triticum aestivum L.) cultivar ‘Zenkoujikomugi’, a single nucleotide polymorphism (SNP) in the promoter of MOTHER OF FT AND TFL1 on chromosome 3A (MFT-3A) causes an increase in the level of gene expression, resulting in strong grain dormancy. We used a DNA marker to detect the ‘Zenkoujikomugi’-type (Zen-type) SNP and examined the genotype of MFT-3A in Japanese wheat varieties, and we found that 169 of 324 varieties carry the Zen-type SNP. In Japanese commercial varieties, the frequency of the Zen-type SNP was remarkably high in the southern part of Japan, but low in the northern part. To examine the relationship between MFT-3A genotype and grain dormancy, we performed a germination assay in three wheat-growing seasons. On average, the varieties carrying the Zen-type SNP showed stronger grain dormancy than the varieties carrying the non-Zen-type SNP. Among commercial cultivars, ‘Iwainodaichi’ (Kyushu), ‘Junreikomugi’ (Kinki-Chugoku-Shikoku), ‘Kinuhime’ (Kanto-Tokai), ‘Nebarigoshi’ (Tohoku-Hokuriku), and ‘Kitamoe’ (Hokkaido) showed the strongest grain dormancy in each geographical group, and all these varieties, except for ‘Kitamoe’, were found to carry the Zen-type SNP. In recent years, the number of varieties carrying the Zen-type SNP has increased in the Tohoku-Hokuriku region, but not in the Hokkaido region. 相似文献
49.
Three apple (Malus×domestica) cultivars and 11 Malus accessions have been investigated by the probe hybridization method on their mitochondrial DNA (mtDNA). The gene probes used were: coxI, coxII, atpA, atp6, and atp9. Our results revealed enough variation to characterize ten mtDNA haplotypes among the Malus genotypes examined. The taxonomic and phylogenetic implications of mtDNA polymorphism are also discussed. 相似文献
50.
Seventy-two accessions covering six varieties of Cucumis melo were characterized by using 35 morphological characters with emphasis on shelf-life, and the relationships between shelf-life
and related characters was investigated. Principal component analysis (PCA) revealed that development period of plant and
fruit, size of seed and fruit, shelf-life, stem hair, flesh juiciness, netting, abscission of peduncle, rapid yellowing of
epidermis at maturity, Brix value, and color of flesh and epidermis etc. were the principal characters to discriminate melon
accessions examined in the present study. According to the scatter diagram, vars. acidulusand makuwa, both of which belong to the Oriental melon, are closely related because of their short growth duration, small seed, thin
pericarp and poor shelf-life, while American cantaloupe (var.reticulatus) and European cantaloupe (var. cantalupensis) are rather closely related due to their climacteric fruit with orange flesh, slipped peduncle and rapid yellowing of epidermis
at maturity, which is closely related with their shelf-life. PCA also indicated that var. saccharinus was closer to var. inodorus than to the other varieties, due to their requirement of long period for development, large size of seed and fruit, and half-
or non-slipped peduncle. Shelf-life of melon fruit was significantly correlated with the following characters: quality of
flesh, size of seed and fruit, abscission of peduncle, development periods of plant and fruit, rapid yellowing of epidermis
at maturity, Brix value and color of flesh and epidermis. Accessions with good shelf-life were mostly found in vars. saccharinus and inodorus.
This revised version was published online in July 2006 with corrections to the Cover Date. 相似文献