Showing papers by "Rural Development Administration published in 2002"

AFLP analysis of diploid species in the genus Vigna subgenus Ceratotropis

Abstract: A representative set of germplasm of genusVigna subgenus Ceratotropis specieswas used to analyze genetic diversity using amplified fragment lengthpolymorphism (AFLP) methodology. The germplasm was selected based onmorphological diversity and geographic origin and includes 18 out of the 21species in the subgenus Ceratotropis. Genetic diversitywithin and between taxa was measured using information generated by AFLP bandpolymorphism from which Jaccard's similarity coefficient and nucleotidediversity were estimated. The data were also used to generate phenograms tovisualize relationships among analyzed accessions. All species in sectionsCeratotropis and Aconitifoliae arewell separated. However, most of the species in sectionAngulares show a high level of similarity suggesting a lowlevel of genetic differentiation. In section Angulares onespecies, V. trinervia, is welldifferentiated from the other species and represents a separate evolutionarybranch between section Ceratotropis and other species insection Angulares. The relationships between the newlydescribed species V. aridicola,V. exilis, V.nepalensis and V.tenuicaulis and other species in the subgenusCeratotropis are described for the first time based on AFLPdata.

Some Biochemical Evidence on the Selective Insecticide Toxicity between the Two Aphids, Aphis citricola and Myzus malisuctus (Homoptera: Phididae), and Their Predator, Harmonia axyridis (Coleoptera: Coccinellidae)

Abstract: This experiment was carried out to compare the differences in biochemical enzyme activity on the selective insecticide toxicity between the two species of aphid, Aphis citricola van der Goot and Myzus malisuctus Matsumura, and their predator, Harmonia axyridis Pallas Esterase activities between the two species of aphids and between the two stages of H axyridis were significant different Glutathione S-traasferase (GST) activity toward 1-chloro-2, 4-dinitrobenzene (CDNB) was much higher than 1, 2-dichloro-4-nirobenzene (DCNB) in all species tested No DCNB conjugation was detected in A citricola and M malisuctus The predator, H axyridis, had much higher GST activity than the preys, A citricola and M malisuctus GST activity toward CDNB in H axyridis adult was highest, even 62-fold higher activity than H axyridis larva M malisuctus had much higher GST activity than A citricola The degree of acetylcholinesterase (AChE) inhibition by phosphamidon among all three species tested was significantly varied The concentration of phosphamidon required for 50% AChE inhibition was lowest in H axyridis larva, while highest in M malisuctus There fore, elevated GST activity and target-site insensitivity may be largely associated with the differential susceptibility between larva and adult of H axyridis However, differential susceptibility between A citricola and M malisuctus may be due to other various biochemical mechanisms responsible for the multiple selective toxicity, including elevated GST activity and target-site insensitivity

Relationship between heterosis and genetic divergence in ‘Tongil’‐type rice

Abstract: Improving grain yield and quality of'Tongil'-type rice (indica/japonica) continues to be a major breeding objective in Korea. In this study, genetic divergence among 13 'Tongil'-type rice cultivars was evaluated and the relationship between genetic distance and hybrid performance in all possible nonreciprocal crosses between them assessed. The 78 F 1 hybrids together with the 13 parents were evaluated for eight traits of agronomic importance, including yield, in a replicated field trial. The 13 parents were examined for DNA polymorphism using 71 microsatellite or simple sequence repeats and 46 random decamer oligonucleotide primers. A total of 319 polymorphic variants were generated and, based on the polymorphism data, genetic distances (GDs) ranged from 0.021 to 0.437. Cluster analysis based on GDs revealed associations among cultivars which was in agreement with the pedigree data. Heterosis was observed in hybrids for most of the traits, and yield exhibited the highest heterosis among the eight traits examined. The correlation values of GDs with F 1 performance were mostly non-significant, except for yield, culm length and spikelets per panicle. The correlations of GDs with midparent and better-parent heterosis were not significant enough to be of predictive value. These results indicate that GDs based on the microsatellite and random amplified polymorphic DNA (RAPD) markers may not be useful for predicting heterotic combinations in 'Tongil'-type rice and support the idea that the level of correlation between hybrid performance and genetic divergence is dependent on the germplasm used.

Cryopreservation of Citrus aurantifolia seeds and embryonic axes using a desiccation protocol.

Abstract: The desiccation and freezing tolerance of seeds, with and without testas, and embryonic axes of Citrus aurantifolia were investigated Seeds were desiccated with silica gel, under the laminar air flow cabinet or by placing them on a laboratory bench Whatever the desiccation method employed, survival before and after cryopreservation was higher for seeds without testas When freezing intact seeds, the highest survival percentage (413 %) was achieved after desiccation to 73 % moisture content (fresh weight basis) on the laboratory bench Survival of seeds cryopreserved without testas could reach up to 85 % after desiccation under the laminar air flow cabinet or on the laboratory bench, corresponding to moisture contents of 71 and 45 %, respectively After desiccation with silica gel, survival reached a maximum of 600 %, for a seed moisture content of 33 % Survival of control embryonic axes was high (80-100 %) whatever the sucrose concentration in the preculture medium and the duration of the desiccation period After cryopreservation, no survival was noted with embryonic axes, which had not been precultured nor desiccated Survival of non-desiccated embryonic axes after cryopreservation increased progressively in line with increasing sucrose concentrations in the preculture medium, from 75 % with 01 M sucrose to 775 % with 07 M sucrose Survival of desiccated and cryopreserved embryos was always high, whatever the preculture treatment and desiccation period, ranging from 558 % to 925 %

BAN103, a pollen-preferential gene, from Chinese cabbage and its promoter activity.

Abstract: We isolated and characterized a pollen-preferential gene, BAN103, from Chinese cabbage and analyzed the activity of its promoter. The BAN103 cDNA and genomic clone that contained the full-length gene were sequenced. The BAN103 gene is a single copy in the Chinese cabbage genome, and divided into three exons by two introns. The deduced sequence of 68 amino acids showed a homology with the Brassica oleracea pollen coat protein, as well as several cold-induced proteins. BAN103 transcription was restricted in anthers, but not in pistils, sepals, or non-reproductive tissues. Its transcription is also regulated developmentally. It was first detected after microspore releasing; it increased until the pollen matured. The BAN103 gene promoter was fused with a GUS structural gene. This recombinant plasmid was transformed to Chinese cabbage and tobacco. The GUS expression was detected pollen-preferentially in transgenic tobacco plants. The pollen-preferential activity of this promoter was retained within 176 bp from the translation start codon. The GUS transcription and translation were not coincident in transgenic tobacco pollen. GUS transcripts appeared just after microspore release, and that translation started as the pollen began to dry in mature anthers.

Dermal pharmacokinetics of the insecticide furathiocarb in rats

Abstract: The pharmacokinetics of furathiocarb were studied in vivo in male Sprague–Dawley rats following dermal treatment. HPLC and post-column derivatization were used for the analysis of furathiocarb and its metabolites (carbofuran, 3-hydroxycarbofuran and 3-ketocarbofuran). Carbofuran and 3-hydroxycarbofuran were detected in plasma and urine rather than furathiocarb. 3-Ketocarbofuran, another potential metabolite, was not observed in any sample. The concentration of carbofuran was higher than that of 3-hydroxycarbofuran in plasma, but the reverse was the case in urine. The corresponding area under the plasma concentration–time curve, Tmax, and Cmax values of carbofuran and 3-hydroxycarbofuran for 1500 mg kg−1 doses were 2.4–8.0 mg equiv h ml−1, 12 h and 0.1–0.4 mg equiv ml−1, respectively. T1/2 was calculated only for 3-hydroxycarbofuran (28 h). Two metabolites were excreted in a dose-dependent manner without saturation. © 2001 Society of Chemical Industry

Scientific basis for establishing country CH4 emission estimates for rice-based agriculture: A Korea (south) case study

Abstract: Methane emission inventory, based on several experimental results regarding the effect of water management, application of organic matter, cultural method, and rice type with field growth duration on methane emission factors was established for Korea specific conditions. Annual methane emission was estimated to be 410 Gg CH4in 1990 and 345 Gg CH4 in 1999. This annual emission estimated as a Korean specific modification is an average of 17.6 and 32.9%, lower than the OECD default value and maximum scaling of the IPCC default, respectively. This Korean modified average is 4.5 times higher than the minimum scaling of IPCC default.

Change in weed control studies of rice paddy fields in Korea

Abstract: This paper was reviewed on the research status of weed control according to cultivating patterns of rice in Korea. Weed control study in a nursery bed was chiefly carried out to control the species of barnyardgrass at the times of machine transplanting. Propanil and nitrofen were applied successfully in wet-nursery beds, and chlornitrofen and pyrazolate/butachlor were also successfully applied in protected semi-irrigated rice nursery beds in the 1970s. Sequential application of herbicides in the mid-1980s has resulted in the end of hand weeding. In machine transplanting, basic research such as the selection of herbicides was conducted in the early 1970s, and its related research including crop injury, seedling age, and reaction of cultivars were done in the late 1970s to early 1980s. Effects of the continuous application of herbicides and its methods of labor saving for rice cultivation were studied in the mid to late 1980s. When the rice planting methods were newly established, such as transplanting when seedlings were 10-days-old and direct seeding from the early 1990s, weed control research relating to herbicides was carried out (e.g. herbicide registration, crop injury, water management, appropriate application time, and neighboring application with insecticide). Weed control for the dill seeding of fields in wetted and reclaimed saline land have been experimented with, particularly in terms of the physio-ecological characteristics and the control of problematic weeds, and the resistance of weeds to herbicides was also investigated systematically.

The genus Pseudococcus (Westwood) (Sternorrhyncha: Pseudococcidae) of Korea

Abstract: Four species of Pseudococcus (Sternorrhyncha: Pseudococcidae) from Korea were reviewed with redescriptions and illustrations of adult females. Among them, two species, P. cryptus Hempel, 1918 and P. dendrobiorum Williams, 1985, are reported for the first time from the Korean Peninsula, and one species, P. longispinus (Targioni Tozzetti, 1867), is newly known from South Korea. A key is given for the adult females.

Identification of RAPD and SCAR markers linked to the flesh adhesion gene F in peach (Prunus persica (L.) Batsch

Abstract: SummaryFlesh adhesion to the stone in peach (Prunus persica (L.) Batsch) fruits can be categorized into three groups: freestone, semi-clingstone and clingstone. Flesh adhesion is known to be determined by a single gene pair F/f with the freestone dominant to clingstone. Bulked segregant analysis and randomly amplified polymorphic DNA (RAPD) analysis were performed to detect markers linked to the F/f gene using an F1 progeny of clingstone `Yumyeong' (ff) 3 freestone `Baekhyang' (Ff). Four dominant coupling-phase RAPD markers linked to the gene, designated as OPB051300, OPD20580, OPI071050 and UBC4391400 were identified from 578 10-mer primers examined. The co-segregation of the four markers and the F/f gene was verified using the 95 individuals of the F1 progeny of `Yumyeong' 3 `Baekhyang'. The RAPD markers OPB051300, OPI071050 and UBC4391400 were found to be located at 2.2, 4.4 and 1.1.cM, respectively, on one side of the F/f locus and the marker OPD20580 at 11.8.cM on the other side. Two RAPD markers OPB...

Composition for inhibiting HIV activity extracted from Paecilomyces sp. (Tochu-kaso) J300

Abstract: The present invention relates to a composition form inhibiting HIV activity comprising the extract of Paecilomyces sp. (Tochu-kaso) J300. More particularly, the present invention relates to a composition for inhibiting HIV activity comprising 3-[5-(methoxy-ethyl)-3,6dioxo-piperazine-2-yl]propionic acid represented by Formula 1 and 4-methyl-2-[(pyrolidine-2-carbonyl)-2-amino] pentanoic acid represented by Formula 2 that are extracted from Paecilomyces sp. (Tochu-kaso) J300; and to a medical composition and food composition containing the same.

Dietary sorbose failed to ameliorate hyperglycemia in alloxan-injected diabetic mice

Abstract: Abstract Kita, K., Kitayama, Y., Nagao, K., Hwangbo, J., Furuse, M. and Okumura, J. 2002. Dietary sorbose failed to ameliorate hyperglycemia in alloxan-injected diabetic mice. J. Appl. Anim. Res., 21: 49–55. The influence of dietary sorbose on body weight change, food intake and hyperglycemia in alloxan-injected diabetic mice was examined. Body weight of alloxan-injected diabetic mice was markedly decreased by feeding a sorbose diet. The lower food intake of mice given sorbose was observed from day 2 of experiment. Analysis of covariance to assess the effect of alloxan injection on the relationship between food intake and body weight change except the influence of different dietary sugar was conducted. It showed that only when mice were fed the diet containing sorbose, body weight change could be explained by the difference in food intake caused by alloxan injection. Blood glucose concentration in alloxan-injected diabetic mice was not decreased by feeding the sorbose diet to the level of intact normal mice given sucrose. In conclusion, dietary sorbose failed to ameliorate hyperglycemia in alloxan-injected diabetic mice.