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1.
草地贪夜蛾缅甸虫源迁入中国的路径分析   总被引:11,自引:0,他引:11  
草地贪夜蛾Spodoptera frugiperda(J.E. Smith)对非洲和南亚国家的入侵已对全球粮食安全造成重大影响,该虫2018年年底已在缅甸形成虫源基地,并零星进入中国云南西南部地区。本文利用历史数据分析了缅甸和华南地区春、夏两季(3-8月)925 hPa夜间平均风温场,并模拟预测了缅甸地区草地贪夜蛾在此期间进入中国的迁飞轨迹以及主要降落和波及的地区。结果表明:3-4月盛行的微弱西风不利于远距离迁移,但成虫的自主飞行可形成对云南和广西局部地区的近距离入侵;进入5月份后,随着西南夏季风的加强,云南和广西全境成为缅甸虫源的主要迁入地,并可能波及贵州、广东、海南和湖南等省。因此,4月份之前要重点监控云南和广西地区草地贪夜蛾的发生与为害,此后,应将监控区域扩大至中国中南部地区的各个省份。  相似文献   
2.
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   
3.
在缅甸13个含葡甘聚糖的野生魔芋种中,黄魔芋、白魔芋和红魔芋是当地民众习惯上按色泽进行区分的3类魔芋,每类又各包含几个种。其中, 上缅甸以红魔芋和缅甸白魔芋居多,下缅甸则以黄魔芋和耐热型白魔芋(A. variabilis)为多。缅甸魔芋现仍以野生资源为主,加工品以干片为多,大宗产品出口中国,部分销往日本。因比较优势明显,日本已开始与缅方合作在缅规模化种植弥勒魔芋。  相似文献   
4.
Rodents and weeds are important pests to rice crops in Southeast Asia. The interaction between these 2 major pests is poorly documented. In temperate cereal systems, seeds of grass weeds can be an important food source for rodents and weed cover along crop margins provides important refuge for rodents. In 2012 and 2013, a replicated study (n = 4) in Bago, Myanmar compared 4 treatments (rodents and weeds; no rodents and weeds; rodents and no weeds; no rodents and no weeds) each of 0.25 ha in transplanted rice. Weeds were managed with hand weeding in the wet season, and hand weeding and herbicides in the dry season. Plastic fences were installed to exclude rodents. We examined the weed cover and relative abundance of weed species, rodent damage, rodent population dynamics and rice yield loss caused by rodents and weeds. The dominant rodent species was Bandicota bengalensis. In the dry season, Cyperus difformis was dominant at the tillering stage and Echinochloa crus‐galli was the dominant weed species at the booting stage. In the wet season E. crus‐galli was a dominant weed throughout the season. Damage by rodents was higher in the dry season. There were larger economic benefits for best weed management and effective rodent control in the dry season (258 US$/ha) than in the wet season (30 US$/ha). Concurrent control of weeds in and around rice fields combined with coordinated community trapping of rodents during the early tillering stage and ripening stage of rice are recommended management options.  相似文献   
5.
珠芽魔芋葡甘聚糖含量高、粘度大,适宜缅甸高温高湿热区环境生长。因品种多样、气候适宜、土壤肥沃、降雨充沛、人力成本低、土地廉价等独特优势,日本同行加快了入缅的步伐。本文对中日2国魔芋界在缅甸市场的竞争提出应对建议。  相似文献   
6.
东南亚、南亚地区是世界上重要的稻米产区,稻米在民众饮食生活和国家社会政治中占有重要地位,民众生活中也保存了非常悠久和丰富的稻作文化习俗及稻谷起源神话传说。本文分析了水稻在东南亚、南亚主要国家印度、印度尼西亚、泰国、越南、菲律宾、孟加拉国、缅甸的作用、地位、生产、消费、文化等情况,并指出了印度、印度尼西亚稻文化的主要标志。  相似文献   
7.
[目的]以中老缅(中国-老挝-缅甸)3国接壤地带为例,通过对其土地利用/覆被的演变过程及生态状况的评估,为该区土地资源的合理利用与生态风险的降低防控提供依据。[方法]基于研究区土地利用/覆被遥感影像数据,通过构建土地利用/覆被变化趋势与状态指数等模型,对其2005-2017年的演变过程及生态状况进行测度。[结果]①研究区以林地、耕地为主导,土地利用组合的一致性较强,但作为多国接壤地带,该区土地利用程度存在一定的国别分异;②随时间演进,研究区土地利用的结构及变化幅度均发生了显著的时空及地类分异,其中林地扩张显著,耕地大幅减少而草地及水体的面积变化相对平稳,后6 a的土地利用变化幅度整体高于前6 a;③12 a间,研究区土地利用变化整体呈不平衡状态,各地类间的变化趋势与状态差异较为显著。随时间演进,受林地外延扩张态势减弱等影响,研究区土地利用变化的稳定性有所增强,但各地类间的变化趋势与状态差异略显增加;④2005-2017年,研究区生态状况整体改善,且国别与空间分异有所减小,12 a间,老挝段生态状况整体较优,缅甸段次之,而中国段的生态状况相对较差,生态综合功能高值区与3国交界处间的距离整体减小。[结论]研究区土地利用/覆被的演变过程及生态状况存在一定的国别分异及阶段性变动特征,中老缅3国对其接壤地带生态本底功能的修复与提升工作正不断增强。  相似文献   
8.
2012年10月—2013年1月在缅甸安达曼海域探捕期间,根据随机选取的650尾浅色黄姑鱼Nibea coibor样本生物学数据,对该鱼种的生物学特性进行了分析。结果表明:浅色黄姑鱼全长为138~459 mm,平均全长为243 mm,体长为109~381 mm,平均体长为200 mm,体质量为25~868 g,平均体质量为214g;全长(TL)与体长(BL)的关系式为TL=0.8626BL-8.4845(R2=0.9536),雌、雄个体间全长和体长分布均无显著性差异(P>0.05);体质量(BW)与体长(BL)的关系式为BW=0.0001BL2.713(R2=0.9159);雌性与雄性之比为1.19∶1,性成熟度以Ⅱ期和Ⅲ期为主;摄食等级以2、3级为主,占总样本数的69.69%,摄食等级为1~4的个体平均体长间无显著性差异(P>0.05)。  相似文献   
9.
There is a variety of professions working with village chickens in developing countries, including farmers, veterinarians and chicken traders. People from all these occupations were involved in a participatory rural appraisal to investigate husbandry practices and trade of village chickens in Myanmar. Data were collected in two climatically different regions of the country, in the Yangon and in the Mandalay divisions. The breeding and training of fighting cocks was practised only in the Mandalay division, with well-trained birds sold for very high prices. Apart from this, chickens were raised in both regions mainly for small disposable income and were generally sold when money was needed, in particular during religious festivals. Chicken traders on bicycles, often called ‘middle men’, usually purchase birds from farmers in about 10 villages per day. Several ‘middle men’ supply birds to wealthier chicken merchants, who sell these birds at larger chicken markets. There is in general limited knowledge among farmers about the prevention of Newcastle disease via vaccination. Commercial indigenous chicken production is practised in Myanmar, but family poultry farming dominates indigenous chicken production in the country.  相似文献   
10.
The Great Slaty Woodpecker (Mulleripicus pulverulentus) of South and Southeast Asia, the third largest woodpecker species in the world, is currently in the IUCN Red List category of Least Concern. This woodpecker appears associated with old-growth forests, and the rapid reductions in forest cover and old-growth area in Southeast Asia urged examination of its global population trends. We assessed population densities, tree diameter use by the woodpecker, and logging disturbance at 21 transects in four regions across the range of the species: west Borneo, Lingga Island (Riau Archipelago, Indonesia), Tenasserim (Myanmar), and west-central Myanmar. Transect survey effort was 937 km. We assessed rates of deforestation and loss of old-growth forest in the range of the species from expert review reports. By combining population density and forest cover data sets we calculated the global population trend of the species. We found a preference for large diameter trees by foraging and nesting Great Slaty Woodpeckers, and a reduction of the frequency of such trees in logged forests. Across the four study regions, between old-growth forests and logged forests, densities of Great Slaty Woodpeckers were reduced by 80-94%. Although Great Slaty Woodpeckers occur in 15 countries, ca. 70% of the global population occurs in just four countries (Myanmar, Indonesia, Cambodia, and Malaysia), three of which have high annual rates of deforestation and loss of old-growth forest. Our population calculations show that over the past century at least 90% of the global population of the Great Slaty Woodpecker has been lost. At present 26,000-550,000 individuals remain. The current global decline rate of ca. 59% ± SD 17% in three generations justifies IUCN Vulnerable or Endangered status. Contributing factors to the steep decline rate of the species are a long generation time of 5.9-8.2 years and an association with old-growth, lower elevation forests. The Great Slaty Woodpecker case adds an Asian example to a global pattern of specialized woodpeckers that are associated with old or natural forests.  相似文献   
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