Present study was performed to observe the tegumental ultrastructures by the developmental stages which derived from the experimental life cycle of Spirometra erinacei in laboratory conditions. In SEM view, coracidium was spherical in shape with numerous cilia, and its surface was covered with long cilia, tuberclelike projections with millet-like processes, and small holes. The body surface of procercoid was covered with numerous pointed microtriches except that of frontal pit with stout spine-like ones. However that of cercomer was covered with somewhat sparse blunt-tiped microtriches. Plerocercoids of 3 days old resembled the mature procercoid in shape, and their frontal pits were covered with numerous stout spine-like microtriches. However frontal pit and body surface in more than 5 days old ones were covered with conoid microtriches. On the surface of adult scolex, hairly long filamentous and stout short microtriches were mixedly distributed. Filamentous microtriches were more densely distributed in the anterior portion than in the posterior of scolex. The neck and immature proglottid were covered with only stout short conoid microtriches. In TEM view of coracidia, embryophore and oncosphere were obviously distinguished. The embryophore contained numerous glycogen particles, mitochondria and lipid granules. The cilia on the surface of embryophore rooted in the coracidial sheath, and consisted of 9 pairs of microtubules and 2 core complex. The oncosphere was covered with a thin and unarmed tegument, and was multi-nucleated. The protoplasmic layer of procercoid and plerocercoid consisted of disc-shaped bodies, vacuoles and mitochondria. Their tegumental cells commonly retained a nucleus, granular endoplasmic reticulums and secretory granules. The protoplasmic layer of plerocercoid was more compacted than that of procercoid. From the above results, it was confirmed that the tegumental ultrastructures are something different according to the developmental stages of S. erinacei.
Kim, Kwang-Soo;Park, Won;Lee, Yong-Hwa;Lee, Ji-Eun;Moon, Youn-Ho;Cha, Young-Lok;Song, Yeon-Sang
Korean Journal of Plant Resources
/
v.31
no.1
/
pp.77-85
/
2018
The cultivation area of rapeseed (Brassica napus L.) has been increased for oil production and landscaping purpose in Korea. However, as the color of rapeseed flower is very simple, diversified flower color is necessary to improve landscape effect. Interspecific and intergeneric crosses between rapeseed (Brassica napus) and three Cruciferae crops were performed in order to grow diverse flower color of rapeseed. The silique formation rate of interspecific cross rapeseed with cabbage (B. oleracea L) was relatively high (65.8%) and higher than intergeneric cross with rapeseed and radish (Raphanus sativus L.), rapeseed and Orychophragmus, respectively. During silique developing period after artificial pollination, there were many siliques without seeds due to the failure of fertilization. The average number of seed per silique obtained from cross rapeseed and cabbage, rapeseed and radish, rapeseed and O. violaceus were 0.12, 0.4 and 0.12, respectively. The phenotypes of $F_1$ hybrid plants from cross rapeseed and Cruciferae crops were mostly similar to maternal line, but leaf length and leaf width were increased. The interspecific cross of rapeseed and cabbage generated ivory color of flower which is the medium color of parents, and intergeneric cross of rapeseed and O. violaceus created entities with larger flowers which seems to enhance landscape effect. The fatty acid composition of most hybrid seeds intermediated of the two parents for oleic acid, linoleic acid and linolenic acid, content. Whereas hybrid of rapeseed and radish produced less erucic acid than radish parent.
Lee, Hee-Bong;Choe, Bong-Ho;Lee, Won Koo;Ji, Hee Chuung
Korean Journal of Agricultural Science
/
v.20
no.2
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pp.125-132
/
1993
This study was carried out to understand the relationship between sources and sinks in tillering maize hybrid. A non-tillering hybrid was included as check hybrid, The following treatments were imposed on the two hybrids at tasseling stages: 1) no leaves removed, 2) all leaves removed, 3) leaves above 1st ear node removed, 4) leaves below 1st ear node removed and 5) only 1st ear removed. The experiment was arranged in a split plot with hybrids as main plots and treatments as sub plots. Results obtained were summarized as follows: Plant heights in control were significantly higher in both hybrids than other treatments, No significant differences of plant height were observed among treatments of leaf removal in both hybrids. No significant differences of kernel weights of plant were found between locations of leaf removal, But seed weight of tillering hybrids was about 10 to 15% heavier than that of non-tillering hybrid. Stem weight showed the same tendency as the kernel weights. Leaf removal above the ear node lowered kernel weight significantly up to 60% compared with no leaf removal. The leaf removal below the ear node lowered the kernel weight about 40%. The effects of leaf removal on kernel weight was more serious in the non-tillering hybrid than in the tillering hybrid. Contribution of each part to the total dry matter varied with position of leaf removal. When no leaves were removed, contribution of each part to the total dry matter was great in the order of kernel weight, leaf weight and culm weight. When leaves above the ear node were removed, the contribution of each part to the total dry matter was in the order of culm weight, leaf weight and kernel weight. When leaves below the ear node were removed, the contribution of kernel weight was greater than the contribution of leaf and culm weights.
Objective of this study was to select ectomycorrhizal fungi for black spruce(Picea mariana) inoculation to overcome the growth inhibitory effects of Kalmia angustifolia. Nineteen isolates representing 11 species of ectomycorrhizal fungi were tested for their abilities to grow and form mycorrhizae with black spruce seedlings in the presence of water leachate of leaves of Kalmia. Mycelium growth of 9 isolates were inhibited by the leaf leachate. Colony diameter and biomass of the other 10 isolates were either increased or unaffected under the same conditions. Acidic pH of the culture medium(pH 3 and 4) inhibited some of the fungi, but a combination of acidic pH and the leaf leachate was more inhibitory. Thirteen isolates were able to form ectomycorrhizae with black spruce in presence of 25% leaf leachate in pure culture. Four isolates, Paxillus involutus(NF4), Cenococcum geophilum(GB12), Laccaria laccata(GB23), and E-strain(GB45) formed mycorrhizae more successfully than the others in presence of up to 50% Kalmia leaf leachate. Black spruce seedlings pre-inoculated with these fungi were grown with Kalmia leaf leachate and live Kalmia plants during a four month greenhouse experiment. Abundant mycorrhizae(77-91% of root tips) were developed on seedlings pre-inoculated with P. involutus, L. laccata and E-strain but relatively poor mycorrhization(32% of root tips) resulted with C. geophidum. Over 90% of the short root mycorrhizae were attributed to the inoculated fungi although indigenous mycorrhizae also occurred on most seedlings. Persistence of the mycorrhizae was not affected by living Kalmia plants. Over 80% of the mycorrhizae on seedlings inoculated with P. involutus, L. laccata and E-strain and 53% of the mycorrhizae on seedlings inoculated with C. geophilum were attributable to the inoculant fungi. Control seedlings formed about 45% ectomycorrhizal short roots with indigenous fungi. The L. laccata and C. geophilum inoculated seedlings exhibited enhanced mycorrhizae formation in presence of Kalmia leaf leachate. Mycorrhizae formation with inoculant fungi was 4-15% lower at pH 4 than at pH 5, with the greatest inhibition occurring for L. laccata. Seedlings inoculated with P. involutus had the greatest shoot and root growth followed by L. laccata and E-strain inoculated seedlings. The P. involutus and L. laccata inoculated seedlings were significantly taller with more shoot dry biomass than the uninoculated(control) seedlings. E-strain inoculated seedlings had significantly higher shoot dry biomass and significantly lower number of first order lateral roots compared to the control but other growth parameters such as height, root dry weight and number of short root tips were not significantly different from the control. Seedlings inoculated with C. geophilum were not significantly different from the uninoculated seedlings in any of the growth parameters except for the number of first artier lateral roots which was significantly less than the control seedlings.
Three Pinus densiflora populations as shown in location map (Fig. 1) were studied in 1977. These succeed the population numbers 10, 11 and 12 after the preceeding populations. Following the previous study methods, 20 trees were chosen from each population and the morphological characteristics such as tree forms, branching habit, needle and wood properties were investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 40 to 45. The growth performances of trees of population 10 and 11 was similar, but 12 seemed to be inferior more or less. 2. The ratios of clear bole length was 0.53 in population 12 as the highest but 0.43 for population 10 as the lowest. 3. The population 12 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown length) 1.65 though the mean branching angle indicates almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between populations as shown in Fig. 3 and 4. 5. No inter-population differences in serration density of needle was shown but significant inter and intra-population and individual differences (within population) in number of stomata rows and resin duct. 6. Population 12 shown 0.119 of resin duct index as the maximum. 7. The pattern of diameter growth, analyses based on the width of 10-year-ring segment unit (for example, the 1st segment denotes the width between pith center and 10th year ring and the 2nd one is from 11th to 20th year ring and so on.), was alike among populations as shown in Fig. 9. 8. No significant differences between population in mean summer wood percentages as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 10 and 11 however vice versa in population 12. 9. The fiber length was increased with the increase of age but no differences between populations as shown in Fig. 12.
For screening of autoregulator receptor gene from Streptomyces longwoodensis, PCR was performed with primers of receptor gene designed on the basis of amino acid sequences of autoregulator receptor proteins with known function. PCR products were subcloned into the BamHIsite of pUC19 and transformed into the E. coli $DH5{\alpha}$. The isolated plasmid from transformant contained the fragment of 100 bp, which was detected on $2\%$ gel after BamHI treatment. The insert, 100 bp PCR product, was confirmed as the expected internal segment of gene encoding autoregulator receptor protein by sequencing. Southern and colony hybridizations with the 100 bp fragment as a probe allowed to select a genomic clone of S. longwoodensis, pSLT harboring a 4.4 kb SphI fragment. Nucleotide sequencing analyses revealed a 651 bp open reading frame(ORF) were isolated protein showing moderate homology ($35{\sim}46\%$) with the ${\Gamma}$-butyrolactone autoregulator receptors from Streptomyces sp., and this ORF was named sltR The sltR/pET-17b plasmid was constructed to overexpress the recombinant SltR protein (rSltR) in E. coli BL21 (DE3)/pLysS, and the rSltR protein was purified to homogeneity by DEAE-Sephacel column chromatography, and DEAE-5PW chromatography (HPLC). The molecular mass of the purified rSltR protein was 55 kDa by HPLC gel-filtration chromatography and 28 kDa by SDS-PAGE, indicating that the rSltR protein is present as a dimer. A binding assay with tritium-labeled autoregulators revealed that the rSltR has clear binding activity with a A-factor type autoregulator as the most effective ligand.
Genomic relationship matrix (GRM) was constructed using whole genome SNP markers of swine and genomic breeding value was estimated by substitution of the numerator relationship matrix (NRM) based on pedigree information to GRM. Genotypes of 40,706 SNP markers from 448 pure Landrace pigs were used in this study and five kinds of GRM construction methods, G05, GMF, GOF, $GOF^*$ and GN, were compared with each other and with NRM. Coefficients of GOF considering each of observed allele frequencies showed the lowest deviation with coefficients of NRM and as coefficients of GMF considering the average minor allele frequency showed huge deviation from coefficients of NRM, movement of mean was expected by methods of allele frequency consideration. All GRM construction methods, except for $GOF^*$, showed normally distributed Mendelian sampling. As the result of breeding value (BV) estimation for days to 90 kg (D90KG) and average back-fat thickness (ABF) using NRM and GRM, correlation between BV of NRM and GRM was the highest by GOF and as genetic variance was overestimated by $GOF^*$, it was confirmed that scale of GRM is closely related with estimation of genetic variance. With the same amount of phenotype information, accuracy of BV based on genomic information was higher than BV based on pedigree information and these symptoms were more obvious for ABF then D90KG. Genetic evaluation of animal using relationship matrix by genomic information could be useful when there is lack of phenotype or relationship and prediction of BV for young animals without phenotype.
Sohn, Sea Hwan;Kim, Na Young;Park, Dhan Bee;Song, Hae Ran;Cho, Eun Jung;Choi, Seong Bok;Heo, Kang Nyeong;Choi, Hee Cheol
Korean Journal of Poultry Science
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v.40
no.3
/
pp.263-270
/
2013
The vent sexing and the auto-sexing by using sex-linked traits are general sexing methods of day-old chicks. Currently, the feather sexing which is based on the differences in the feather characteristics at hatching is the representative sexing method of chicken, because the late-feathering is sex-linked trait. The feather sexing can be used if the breed has dominant feathering gene (K) in maternal and recessive gene ($k^+$) in paternal. Therefore it is necessary to identify the association of feathering genes and quantitative traits in chickens. In this study, we investigated the influence of the rate of feathering on productive traits in Korean Native Chicken. In results, there was no significant difference between early-feathering chickens and late-feathering chickens in reproductive performance such as fertility and hatchability. Livability, body weights, egg production, egg weight and egg quality also did not significantly differ between early- and late-feathering chickens. Age at first egg was the only trait of those tested in which significant difference was observed. The early-feathering chickens laid eggs 3 days earlier than late-feathering chicken. As a result, there is no influence of feathering phenotypes on productive performance in Korean Native Chickens. Consequentially, establishing the feather sexing strain is available using the Korean Native Chicken breed without considering of the effect of feathering genes on productive traits.
The early senescence mutant induced from Gihobyeo by $\gamma-ray$ irradiation was determined. The mutated gene expression was identified with comparing the characteristic of original cultivar. The mutant had so similar the morphological characteristics to original cultivar that it couldn't be distinguished until senescence occurred at about 20 days after heading. Suddenly yellow leaves were observed within a few days due to great decreases in total chlorophyll and various carotenoid contents. Transmission electron microscopy showed the formation of starch granules, distortion of fine structure of leaf cell organelles, especially grana structures, and the decrease in grain filled after senescence occurred. But banding patterns of total proteins and isozymes have not show any differences, The early senescence mutant will be very useful for study material not only on physiological and biochemical properties of plant senescence but also on gene expression regulating senescence which gives great influence on yield potential and its stability.
Six natural populations of Pinus densiflora S. et Z. as shown in the location map (Flg 1) were studied during 1978. The numerial pouplation codes, 13 to 18. The results of populations 1 to 12 were reported in previous papers. Following the study methods described before, 20 trees were sampled from each population and morpological characteristics such as stem forms, branching habit needle and wood properties investigated. The results are summerized as follows; 1. The mean stand ages were ranged from 36 to 97 of years. The growth performances of trees of population 14. 15 and 18 was similar, but 13, 16, and 17 seemed to be inferior more or less. 2. The ratios of clear bole length were 0.70 in population 18 as the highest but 0.28 for population 16 as the lowest. 3. The population 17 was considered to be a stand of the coarser branching habit having the crown index (The maximum crown diameter/the crown height) 158 though the branching angles were almost horizontal. 4. The differences were observed in the clear bole length ratios and crown-indices between population as shown In Fig. 3 and 4. 5. As to the serration density, number of stomata row and resin duct; the significant differences exist between individual trees within population and also between populations. 6. Population 18 shown resin duct index 0.119 as the maximum. 7. The patterns of diameter growth, based on the width of 10-year-ring segment unit(for example, the 1st segment denotes the with between pith center and 10th year ring and the 2nd one is from 11th to 20th ring and so on.), were alike among populations as shown in Fig 9. 8. Significant differences between population in mean summer wood percentage as well as in wood specific gravity was observed. The values of wood specific gravity were increased with the increase of ages in population 14, 18 however vice versa in population 13, 15, and 17. 9. The fiber length was mereased with the increased of age but no differences between populations as shown in Fig. 12.
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