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1.
Genetic diversity estimates in Cicer using AFLP analysis 总被引:2,自引:0,他引:2
Amplified fragment length polymorphism (AFLP) analysis was used to evaluate the genetic variation among cultivated chickpea and wild Cicer relatives. In total, 214 marker loci were assessed, of which 211 were polymorphic (98.6%) across the 95 accessions that represented 17 species of Cicer. The genetic variation within a species was highest in C. pinnatifidum followed by C. reticulatum and lowest in C. macracanthum. Three main species groups were identified by UPGMA clustering using Nei's pair‐wise distance calculations. Group I included the cultivated species C. arietinum, C. reticulatum and C. echinospermum. Within this group, C. reticulatum accessions were clustered closest to the C. arietinum cultivars ‘Lasseter’, ‘Kaniva’ and ‘Bumper’, supporting the hypothesis that C. reticulatum is the most probable progenitor of the cultivated species. Cicer bijugum, C. judaicum and C. pinnatifidum were clustered together creating group II. Group III contained all nine perennial species assessed and two annual species C. yamashitae and C. cuneatum. The genetic distance detected between group I and group III (0.13) was equivalent to the genetic distance detected between group I and group II (the primary and annual tertiary species, respectively; 0.14). This indicated that the perennial tertiary species may be as valuable for increasing variation to incorporate novel germplasm in the cultigen as the annual tertiary species. 相似文献
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Do Thi Thanh HUONG Vidya JAYASANKAR Safiah JASMANI Hisako SAIDO-SAKANAKA Andrew J. WIGGINTON Marcy N. WILDER 《Fisheries Science》2004,70(3):518-520
4.
Son Truong NGUYEN Masaharu MOTOKAWA Tatsuo OSHIDA Hideki ENDO 《The Journal of veterinary medical science / the Japanese Society of Veterinary Science》2016,78(2):187-198
Southeast Asia is a region of high biodiversity, containing species of plants and animals that are yet to be
discovered. In this region, bats of the subfamily Kerivoulinae are widespread and diverse with six species
recorded in Vietnam. However, the taxonomy of the Kerivoulinae in Asia is complicated. In our study, we used
diagnostic characters and multivariate analysis to determine morphological differences between the genera
Kerivoula and Phoniscus. We showed that the two genera are distinguishable
by the size of second upper incisors, the shape of skull, nasal sinus, canines, second upper and lower
premolars. In addition, the two genera can be osteometrically separated by measurements of the braincase
height, interorbital width and shape of anterior palatal emargination. Our data clearly revealed the
morphological variations in the skull shape of Kerivoula hardwickii in Vietnam. This suggests
a possible separation into three morphotypes, representing cryptic species supported by statistical
differences with wide variation in skull shape, size and teeth. These results demonstrated Kerivoula
hardwickii can be separated three subspecies, and the result will serve as the basis for the future
assessment and classification of this group in Southeast Asia. 相似文献
5.
Townsend KM Hanh TX O'Boyle D Wilkie I Phan TT Wijewardana TG Trung NT Frost AJ 《Veterinary microbiology》2000,72(1-2):69-78
A total of 36 tonsil swab samples were collected from healthy swine prior to slaughter at the abattoirs in Can tho and Tien giang provinces of Southern Vietnam. The presence of Pasteurella multocida in these samples was detected by the combination of direct cultivation and isolation, mouse inoculation and the polymerase chain reaction (PM-PCR). P. multocida was detected in 16 samples by PCR, with 17 strains ultimately isolated. All samples were negative for serogroup B by HSB-PCR and conventional serotyping, with isolates identified as A:3, D:1 or D:3. In addition, all samples were determined to be negative for the P. multocida toxin (PMT). Characterisation of isolated P. multocida by REP-PCR and biotyping revealed nine distinct REP profiles and seven biotypes among the 17 isolates. Some correlation was seen with P. multocida isolated from a previous Australian outbreak of acute swine pasteurellosis, and those isolated from fowl cholera outbreaks in Vietnamese poultry. 相似文献
6.
Xiaoxi Zhang Zengwen Liu Bochao Zhu Yuanhao Bing Nhu Trung Luc Liangzhen Du Zhenhua Zhu 《林业研究》2016,27(3):525-532
The productivity of Robinia pseudoacacia (R.p.) pure forest usually declines at the late growth stage, and reforming it into mixed forests could be a promising way to resolve this problem. When choosing a suitable tree species that can be mixed with R.p., the interspecific relationship is an important issue. Therefore, we gathered the autumn litter fall from R.p. and 10 other species from the Loess Plateau of China were mixed in dual species litterbags (R.p. + each other species) and buried them in soil for a 345 days lab decay incubation. We measured the litter mass loss and nutrient contents to determine whether the nutrient release was affected by mixed species litter decomposition. The impacts of mixed litter decomposition on macro-elements release were more obvious than on micro-elements. The litters with similar substrate quality might show variable impacts on nutrients release in mixed decomposition. The C loss and release of nutrient was improved by descending order when R.p. litter was mixed with Hippophae rhamnoides, Ulmus pumila, Populus simonii, Larix principis-rupprechtii and Quercus liaotungensis (Q.l.). But, except for Q.l., only the other species were recommended as suitable mix-plants for R.p. since promoting a high turnover of the nutrient in the litter compartment and a rapid availability for tree. 相似文献
7.
Kang-Seuk Choi Soo-Jeong Kye Ji-Ye Kim Thanh Long To Dang Tho Nguyen Youn-Jeong Lee Jun-Gu Choi Hyun-Mi Kang Kwang-Il Kim Byung-Min Song Hee-Soo Lee 《Tropical animal health and production》2014,46(1):271-277
Newcastle disease virus (NDV) causes significant economic losses to the poultry industry in Southeast Asia. In the present study, 12 field isolates of NDV were recovered from dead village chickens in Vietnam between 2007 and 2012, and were characterized. All the field isolates were classified as velogenic. Based on the sequence analysis of the F variable region, two distinct genetic groups (Vietnam genetic groups G1 and G2) were recognized. Phylogenetic analysis revealed that all the 12 field isolates fell into the class II genotype VII cluster. Ten of the field isolates, classified as Vietnam genetic group G1, were closely related to VIIh viruses that had been isolated from Indonesia, Malaysia, and Cambodia since the mid-2000s, while the other two field isolates, of Vietnam genetic group G2, clustered with VIId viruses, which were predominantly circulating in China and Far East Asia. Our results indicate that genotype VII viruses, especially VIIh viruses, are predominantly responsible for the recent epizootic of the disease in Vietnam. 相似文献
8.
Partho Pratim Debnath Nguyen Dinh-Hung Suwimon Taengphu Vuong Viet Nguyen Jerome Delamare-Deboutteville Saengchan Senapin Chadag Vishnumurthy Mohan Ha Thanh Dong Channarong Rodkhum 《Journal of fish diseases》2022,45(1):77-87
Sixteen countries, including Bangladesh, have reported the presence of tilapia lake virus (TiLV), an emerging tilapia pathogen. Fish polyculture is a common farming practice in Bangladesh. Some unusual mortalities reported in species co-cultivated with TiLV-infected tilapia led us to investigate whether any of the co-cultivated species would also test positive for TiLV and whether they were susceptible to TiLV infection under controlled laboratory experiments. Using 183 samples obtained from 15 farms in six districts across Bangladesh, we determined that 20% of the farms tested positive for TiLV in tilapia, while 15 co-cultivated fish species and seven other invertebrates (e.g. insects and crustaceans) considered potential carriers all tested negative. Of the six representative fish species experimentally infected with TiLV, only Nile tilapia showed the typical clinical signs of the disease, with 70% mortality within 12 days. By contrast, four carp species and one catfish species challenged with TiLV showed no signs of TiLV infection. Challenged tilapia were confirmed as TiLV-positive by RT-qPCR, while challenged carp and walking catfish all tested negative. Overall, our field and laboratory findings indicate that species used in polycultures are not susceptible to TiLV. Although current evidence suggests that TiLV is likely host-specific to tilapia, targeted surveillance for TiLV in other fish species in polyculture systems should continue, in order to prepare for a possible future scenario where TiLV mutates and/or adapts to new host(s). 相似文献
9.
This paper describes the characteristics of data about wood and wood-processing products published in Vietnam. The characteristics
include inconsistency of data published by major data sources, lack of necessary data, and irregular publication frequency.
Reasons are identified for the existence of the above characteristics of data for the wood and wood-processing industries,
including recent changes in the functions of state statistical organizations and unclear concepts of data published. These
characteristics create difficulties for researchers and policy-makers working at the Ministry of Agriculture and Rural Development
for analysing policies and establishing supply targets for the wood and wood-processing industries in 5-year economic plans.
To improve the statistical system, co-operation between state organisations and the information network (e.g. computers and
internet connection) requires strengthening. 相似文献
10.
Magnetic fields (MFs) have been applied for the first time in orchid micropropagation. Protocorm-like bodies (PLBs) – approximately 3 mm in diameter – first derived from leaf segment culture of Phalaenopsis Gallant Beau ‘George Vazquez’, were subcultured every 2 months, and served as initial explants. The proliferation of Phalaenopsis PLBs in liquid medium in the Miracle Pack® culture system was affected by the action of different intensities and polarities of MFs: 0.1, 0.15 and 0.2 Tesla (T) at North (N) and South (S) poles. The MF of 0.1 T – S resulted in the greatest fresh weight of regenerated PLBs. The average number of neo-PLBs formed per clusters in the PLB treated by MF: 0.1–0.2 T was decreased compared to the control exposed to natural MF (5 × 10−6 T). The proliferation of PLBs under 0.15 T – MF at both N and S poles for 2 and 7 weeks demonstrated that a longer duration of exposure to an MF of 0.15 T, regardless of the polarity, resulted in greater biomass of newly formed PLBs and smaller average number of newly formed PLBs. The S pole of MF had stronger effects on Phalaenopsis PLBs proliferation than the N pole did in all treatments. 相似文献