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Myanmar indigenous chickens play important roles in food, entertainment, and farm business for the people of Myanmar. In this study, complete mitochondrial D-loop sequences (1232 bp) were analyzed using 176 chickens, including three indigenous breeds, two fighting cock populations, and three indigenous populations to elucidate genetic diversity and accomplish a phylogenetic analysis of Myanmar indigenous chickens. The average haplotype and nucleotide diversities were 0.948 ± 0.009 and 0.00814 ± 0.00024, respectively, exhibiting high genetic diversity of Myanmar indigenous chickens. Sixty-four haplotypes were classified as seven haplogroups, with the majority being haplogroup F. The breeds and populations except Inbinwa had multiple maternal haplogroups, suggesting that they experienced no recent purifying selection and bottleneck events. All breeds and populations examined shared haplogroup F. When 232 sequences belonging to haplogroup F (79 from Myanmar and 153 deposited sequences from other Asian countries/region) were analyzed together, the highest genetic diversity was observed in Myanmar indigenous chickens. Furthermore, Myanmar indigenous chickens and red junglefowls were observed in the center of the star-like median-joining network of 37 F-haplotypes, suggesting that Myanmar is one of the origins of haplogroup F. These findings revealed the unique genetic characteristic of Myanmar indigenous chickens as important genetic resources.  相似文献   
2.
Hybrid composites of epoxy novolac reinforced with short bagasse fibres and short coir fibres were prepared. The mechanical and dynamic mechanical properties of these bagasse-coir hybrid fibres reinforced epoxy novolac composites were investigated with reference to different layering patterns of the composites. The tensile properties of the tri-layer composites are recorded higher than those of the bi-layer composites, whereas the flexural properties of the tri-layer composites are lower than bi-layer composites. The tensile strength of the intimate mix composite is comparable with trilayer composite having bagasse as skin material. The effect of layering pattern on storage modulus (E′), damping behavior (tan δ), and loss modulus (E″) was studied as a function of temperature and frequency. The E′ values of the bi-layer composites are recorded lower than those of tri-layer (bagasse/coir/bagasse) and intimately mixed hybrid composites. The minimum E′ value is obtained for the composites made with coir as skin layer. Bi-layer composite shows maximum damping property. The theoretical modeling showed good correlation with experimental results at above glass transition temperature (T g ), while theoretical model deviates experimental data at lower T g . The Arrhenius relationship has been used to calculate the activation energy of the glass transition of the composites.  相似文献   
3.
In a series of glasshouse and laboratory experiments, lettuce varieties and wild Lactuca species were screened for resistance to the lettuce root aphid, Pemphigus bursarius (Ron.). Several new sources of resistance to P. bursarius development and survival were identified. Extremely high levels of resistance were found in the wild species L. saligna, L. perennis and L. virosa. Resistance was also identified in the lettuce variety Grand Rapids. This resistance is controlled by one or two genes. At least one of these genes is not allelic to the existing Lra gene. Grand Rapids therefore represents a new source of resistance to P. bursarius. This revised version was published online in August 2006 with corrections to the Cover Date.  相似文献   
4.
BACKGROUND: Identification of Bactrocera carambolae Drew and Hancock, B. papayae Drew and Hancock, B. tau Walker, B. latifrons Hendel, B. cucurbitae Coquillett, B. umbrosa Fabricius and B. caudata Fabricius would pose a problem if only a body part or an immature stage were available. Analysis of polymerase chain reaction–restriction fragment length polymorphism (PCR‐RFLP) of cytochrome oxidase I (COI) gene using primers COIR, COIF, UEA7 and UEA10 and restriction enzymes (MseI, RsaI and Alu1) was carried out. The banding profiles in the electrophoresis gel were analysed. RESULTS: The COI gene in six Bactrocera spp. was successfully amplified by COIR and COIF, as well as UEA7 and UEA10, while B. caudata was amplified successfully only by UEA primers. Using COI amplified PCR products and restriction enzymes, distinct banding profiles for B. tau, B. latifrons, B. cucurbitae and B. umbrosa were observed, but not for B. carambolae and B. papayae. However, using UEA7, UEA10 and RsaI, B. caudata could be identified, while B. carambolae and B. papayae might possibly be separated from one another. It was also shown that adult body parts or immature life stages of B. carambolae, B. papayae, B. latifrons and B. cucurbitae produced the same banding profiles as the adults. CONCLUSION: PCR‐RFLP analyses are able to identify positively five Bactrocera species, while B. papayae and B. carambolae might possibly be separated from one another, even if immature life stages or adult body parts are used. Copyright © 2009 Society of Chemical Industry  相似文献   
5.
The medicinal plant Brucea javanica (L.) Merr. (Simaroubaceae) is widely distributed throughout Asia where its bitter fruits have been used in traditional medicine for various ailments. Fifteen C-20 quassinoids were isolated from the fruits of B. javanica and examined for their in vitro antitrypanosomal activities against trypomastigotes of Trypanosoma evansi. Bruceine A, bruceantinol, bruceine C, brusatol, and bruceine B showed strong antitrypanosomal activities with IC(50) values in the range of 2.9-17.8nM, which compared well with the standard trypanocidal drugs diminazene aceturate (IC(50)=8.8nM) and suramin (IC(50)=43.2nM). However, dehydrobruceine A, dehydrobruceine B, and dehydrobrusatol were about 2100, 900, and 1200 times less active, respectively, than bruceine A, bruceine B, and brusatol. The relationship of the structure and antitrypanosomal activity of these quassinoid compounds suggested that the presence of a diosphenol moiety in ring A and the nature of the C-15 side chain are important for their activities against T. evansi. This is the first report on the antitrypanosomal activity of isolated quassinoids.  相似文献   
6.
Microbial-stressed germination of black soybeans leads to generation of a group of oxylipins, oxooctadecadienoic acids (KODEs, including 13- Z, E-KODE, 13- E, E-KODE, 9- E, Z-KODE, and 9- E, E-KODE), and their respective glyceryl esters in addition to glyceollins, a known phytoalexins present in wild and fungi-infected soybeans. Four fungi, Aspergillus niger, Aspergillus oryzae, Rhizopus oligosporus, and white rice yeast ( Aspergillus niger wry), were applied to compare their efficiency on inducing these compounds during black soybean germination. Overall, R. oligosporus, the starter culture used in tempeh fermentation, gives the highest amounts of KODEs and glyceollins. The glyceollins and KODEs were isolated by preparative HPLC, and the structures were determined by (1)H NMR, UV-Vis, and MS spectra. On the basis of the unequal distribution of the KODEs isomers, an enzymatic reaction, instead of a nonenzymatic free radical chain reaction, is responsible for their formations. Together with other oxylipins and glyceollins, the KODEs may contribute to the soybean's defensive response to fungal infection via reaction with protein thiol groups and cell membranes. The stress-germinated black soybeans may be used as ingredients for further processing of novel functional food products with unique nutritional and flavor profiles.  相似文献   
7.
Summary A wide range of cultivated brassica accessions including broccoli, Brussels sprouts, Chinese cabbage, cauliflower, collard, kale and swede material was tested against the cabbage aphid, Brevicoryne brassicae, at HRI, Wellesbourne in the field and laboratory in both 1992 and 1993. In the field, B. brassicae attack was assessed as the proportion of infested plants and the numbers of aphid colonies present. In the laboratory, aphid performance was measured in terms of the pre-reproductive and reproductive period, population increase, and insect mortality. Interpretation of the data was facilitated by plotting sorted accession means against normal order statistics. This statistical approach indicated the spread of variation amongst the accessions and permitted identification of extremes. Partial levels of antixenosis resistance were discovered in red brassicas. Glossy accessions of cabbage and cauliflower possessed antixenosis and antibiosis resistance that lasted throughout the season of crop growth in the field. Other accessions were shown to withstand aphid attack and therefore possessed tolerance. The laboratory studies provided information on mechanisms of antibiosis resistance. The potential value of the different sources of resistance is discussed.  相似文献   
8.
Black soybeans [Glycine max (L.) Merrill] were germinated under fungal stress with food grade R. oligosporus for 3 days and were homogenized and fermented with lactic acid bacteria (LAB) to produce soy yogurt. Fungal stress led to the generation of oxylipins [oxooctadecadienoic acids (KODES) isomers and their respective glyceryl esters] and glyceollins--a type of phytoalexins unique to soybeans. In soy yogurt, the concentrations of total KODES and total glyceollins were 0.678 mg/g (dry matter) and 0.953 mg/g, respectively. The concentrations of other isoflavones (mainly genistein and daidzein and their derivatives) in soy yogurt remained largely unchanged after the processes compared with the control soy yogurt. Germination of black soybean under fungal stress for 3 days was sufficient to reduce stachyose and raffinose (which cause flatulence) by 92 and 80%, respectively. With a pH value of 4.42, a lactic acid content of 0.262%, and a maximum viable cell count of 2.1 x 10 (8) CFU/mL in the final soy yogurt, soy milk from germinated soybeans under fungal stress was concluded to be a suitable medium for yogurt-making. The resulting soy yogurt had significantly altered micronutrient profiles with significantly reduced oligosaccharides and enriched glyceollins.  相似文献   
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