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1.
畜牧业是尼泊尔北部山区的重要生计支柱,提升牧草产量是我国对尼泊尔开展农业技术援助的关键领域。为筛选出适宜尼泊尔北部山区栽培的燕麦品种,于2019年5-10月在尼泊尔热索瓦县郎唐山区对12个燕麦品种（爱沃、太阳神、贝勒1、美达、科纳、林纳、青引1号、青海444、青海甜燕麦、陇燕2号、陇燕3号、Kamadhenu）的物候期、株高、产草量、穗含量、叶茎比和关键营养成分等进行了品比试验。结果表明：美达、科纳、青引1号、青海444、青海甜燕麦和Kamadhenu 6个品种能完成生育期,生育天数在115~141 d,其余多数品种只能达到乳熟期。各燕麦品种的株高为134.8~177.7 cm,其中引进品种太阳神、青海444、青海甜燕麦、美达和林纳的株高较对照品种Kamadhenu高6.3%~20.4%,存在极显著差异（P<0.01）。青海甜燕麦、青海444和美达的干草产量分别达到了14723.0、13491.0和13369.6 kg·hm-2,分别比对照品种Kamadhenu增产36.0%、24.7%和23.6%,差异极显著（P<0.01）。贝勒1、科纳和太阳神的叶茎比分别为0.40、0.38和0.36,是对照品种Kamadhenu的1.50~1.67倍。各燕麦品种的干物质、粗蛋白、总灰分、中性洗涤纤维和酸性洗涤纤维含量变化范围分别为93.5%~95.6%、5.7%~9.9%、4.4%~6.9%、68.2%~78.4%和39.3%~48.7%,其中太阳神的粗蛋白含量是对照品种Kamadhenu的1.57倍,存在极显著差异（P<0.01）。对各燕麦品种的10个农艺性状进行主成分分析及综合评价,结果表明,引进品种青海甜燕麦、美达、青海444和太阳神综合适应性较好,适宜在该地区推广种植。 相似文献
2.
This study was conducted to evaluate incidence and seasonal trends of rabies in dogs and other domestic animals in Bhutan from 1996 to 2009. Time series analysis approach was used to determine the seasonal trend and temporal association between species-specific rabies cases in animals. A total of 814 rabies cases were reported during the 14-year period, of which cattle and domestic dogs accounted for 55% (447/814) and 39% (317/814) of the cases, respectively. The remaining 6% of the cases (50/814) were reported in horses (2%), cats (2%), pigs (1%) and goats (1%). Rabies cases were reported throughout the year with more reports during spring and summer months. The annual patterns of cases were stable from 1996 to 2005, but the incidence increased during 2006 and 2008. Fifty-nine of the 205 sub-districts reported rabies in animals from 1996 to 2009 with increased incidences in the four districts in southern Bhutan, an area located close to the border towns of India. A significant (P < 0.05) positive cross-correlation was observed between the number of cases in dogs and other domestic animals at time lags (months) 1-3 with the highest correlation (r = 0.94, P < 0.05) observed at time lag 0 (same month) indicating that the peak in rabies incidences occur in the same month when both dogs and other domestic animal cases are reported. Regression analysis predicted rabies in other domestic animal when there are reports of rabies in dogs during the previous months. This study provides useful information about the epidemiology of rabies that can be used to plan a rabies control programme in Bhutan. 相似文献
3.
V.R. Monger J.A. Stegeman G. Koop K. Dukpa T. Tenzin W.L.A. Loeffen 《Preventive veterinary medicine》2014
A cross-sectional serological study was conducted in Bhutan between October 2011 and February 2012 to determine the prevalence of antibodies to classical swine fever virus (CSFV), porcine reproductive and respiratory syndrome virus (PRRSV), porcine circovirus type 2 (PCV2), swine influenza virus (SIV) subtype H1N1 and Aujeszky's disease virus (ADV). Furthermore, risk factors for the seropositive status were investigated. 相似文献
4.
Rabies is a serious public health problem in Asia. It causes substantial animal welfare, economic and human health impacts, with approximately 39 000 human deaths each year. Domestic dogs are the main reservoir and source of rabies in Asia. Common constraints for the control of rabies in the countries of Asia include inadequate resources; lack of political commitment to control programs; lack of consensus on strategy; weak intersectoral coordination and inadequate management structure; insensitive surveillance systems; limited accessibility to modern rabies vaccine and supply problems; lack of public awareness and public cooperation; and the existence of myths and religious issues. In this review, we summarize the epidemiology of rabies in both human and animals in each South and South East Asian country, the past and current approaches to control and the prospect for rabies elimination. We conclude that defining the cost of rabies to society and communicating this to decision‐makers might be the key to achieving such an advance. 相似文献
5.
Mani Ram Moktan Georg Gratzer William H. Richards Tek Bahadur Rai Dawa Dukpa Kinley Tenzin 《Forest Ecology and Management》2009
Group selection tree harvest has been proposed as an ecologically sustainable silvicultural technique in mixed conifer forests of the western Bhutan Himalayas. To evaluate this silvicultural technique, we studied the ecological consequences of a group selection tree harvest in mixed conifer forests by assessing 127 circular plots (71 in logged and 56 in unlogged stands) in two forest management units (FMUs). Tree species composition and diversity were similar between logged and unlogged stands. Seedling density and height growth vary by species and were influenced by logging and microsites, with generally taller seedlings found in the logged versus unlogged stands. Early successional shade-intolerant species colonized logged stands. Seedlings growing on bare soil scarified by harvesting had medium vigour while seedlings growing on bryophyte mats showed good vigour in both logged and unlogged stands. Moist sites with a northerly aspect supported profuse conifer seedling regeneration, compared to sites with a dry southerly aspect. Damage to conifer seedlings from herbivore browsing was minimal. Conifer seedling density and height growth was negatively affected by competition from herbaceous vegetation, most notably Salvia officinalis. Group selection tree harvest in southern dry exposures in spruce-dominated stands is silviculturally unsuitable because it alters tree succession. 相似文献
6.
Richard H. Ellis Maryam Nasehzadeh Jean Hanson Yeshi Woldemariam 《Genetic Resources and Crop Evolution》2018,65(2):607-623
Genebanks maintaining seeds for long-term genetic resources conservation monitor seed lots to detect early loss in viability. Monitoring is costly and depletes valuable seed. Three decades of genebank seed germination test results of diverse forage species from 50 legume genera in the International Livestock Research Institute’s medium-term store (circa 8 °C with 5% moisture content) were analysed to determine whether advice on seed monitoring intervals could be derived. Cumulative normal distributions were fitted by probit analysis for each seed lot and compared within each genus. Six patterns of within-genus variation were identified: no detectable trend in germination test results during storage (4 genera); detectable trends, but variable (positive to negative) amongst lots (5); consistent slope of loss in viability amongst lots (17); consistent slope of increase in ability to germinate amongst lots (21); common loss in viability amongst lots (2); common increase in ability to germinate amongst lots (1). Seed lot monitoring intervals for the medium-term store were derived for each of 19 genera with consistent loss in viability across seed lots: three genera provided comparatively rapid deterioration, five met the general expectations for a medium-term store (2–10 years’ maintenance of high viability), whilst 11 provided much better survival. Moreover, 26 further genera provided no evidence as yet of seed deterioration; of these, 22 improved in ability to germinate during storage indicating confounding of hardseededness with viability in germination tests. 相似文献
7.
围封年限对西藏高寒草甸植被特征与土壤养分的影响 总被引：3，自引：0，他引：3
围栏禁牧是高寒草地恢复的重要技术手段之一,但学术界对适宜的围栏年限还存在较大争议。本研究以青藏高原腹地的高寒草甸草地为研究对象,比较分析了退化高寒草甸自由放牧、围封5年、围封7年和围封11年后植物多样性、生物量和土壤理化性质的变化。结果表明:1)相比自由放牧草地,不同年限围封显著提高了退化高寒草甸植物物种丰富度、多样性指数、盖度和地上生物量(P0.05)。不同围封年限之间,围封7年的物种丰富度和多样性指数最高,但与围封5年和围封11年无显著差异(P0.05)。围封5年的地上生物量最高,且与围封11年存在显著差异(P0.05)。2)围封降低了退化高寒草甸土壤容重,显著增加了土壤有机质含量(P0.05)。相比自由放牧草地,不同年限围封提高了高寒草甸土壤全氮、全磷含量。不同围封年限之间,土壤有机质含量随围封年限的增长而增加,土壤全氮和全磷无显著变化(P0.05)。3)总体而言,围封有效恢复了退化高寒草甸的植被与土壤。不同围封年限下,围封5年和7年更有利于退化高寒草甸的植被恢复。 相似文献
8.
This study assessed the sustainability of selection cutting in a community forest (CF) in Bhutan. The harvesting approach differed from cable crane logging operations in an adjacent commercially managed forest by creating much smaller canopy openings. This had many implications for natural regeneration of preferred species. The study was conducted in a late successional broadleaved CF containing 32 genera of tree species dominated by Quercus and Castanopsis and managed for timber, firewood, non-wood forest products and forest grazing. The study was based on a comparison of two forest inventories to assess forest structure and regeneration, a study of stumps to quantify harvesting intensities, and a household survey to quantify livestock holdings and grazing patterns. The study examined different intensities of selection cutting in three blocks of the CF and found that higher intensities of selection cutting did not have a negative impact on: (a) natural regeneration of seedlings and saplings of preferred timber species; (b) the diameter distribution of all species and use categories except for Quercus; (c) the diversity of tree genera; and (d) the percentage of remaining trees with favorable bole shape and form. These results contrasted with findings in the adjacent commercially managed forest. Community management of broadleaved forests with selection cutting appeared to be sustainable and avoid some of the unresolved silvicultural problems associated with commercially managed forests in Bhutan. However more research is needed on the sustainable management of Quercus spp. 相似文献
9.
基于藏北地区饲草缺乏和草地植被退化等问题,开展野生牧草资源的开发利用研究,驯化筛选适宜藏北高寒区种植的优质乡土早熟禾。选取西藏野生的中亚早熟禾（Poa litwinowiana）、渐尖早熟禾（P. attenuata）和冷地早熟禾（P. crymophila）为材料,以国审栽培品种青海冷地早熟禾（P. crymophila cv. Qinghai）为对照,在海拔4 512m环境条件下完成田间种植,分析比较不同早熟禾的生长特性和营养品质。结果显示,随生育期推进,供试材料地上生物量、株高、中性洗涤纤维和酸性洗涤纤维含量呈现逐渐增加的现象,粗蛋白质和粗脂肪含量下降。乳熟期3种材料的地上生物量均显著（P<0.05）高于对照品种,其根系生物量大小排序为渐尖早熟禾>中亚早熟禾>冷地早熟禾>对照;冷地早熟禾的粗蛋白含量显著（P<0.05）高于渐尖早熟禾,渐尖早熟禾的酸性洗涤纤维和中性洗涤纤维含量最低。采用熵权赋值法的灰色系统理论对乳熟期不同早熟禾生产性能及营养品质指标进行综合评价,优劣顺序为渐尖早熟禾>冷地早熟禾（野生种）>中亚早熟禾>青海冷地早熟禾（栽培种）。 相似文献
10.
Guangjie Liu John L. Bernhardt Melissa H. Jia Yeshi A. Wamishe Yulin Jia 《Euphytica》2008,159(1-2):73-82
Recombinant inbred line (RIL) populations of rice are useful genetic sources for map-based cloning of agronomically important
genes. Zhe733 is a high-yielding indica cultivar from China conferring resistance to rice blast (RB), rice water weevil (RWW) and straighthead; whereas Kaybonnet
low-phytic acid 1-1 (KBNTlpa) is a mutant of a tropical japonica cultivar from the US containing low-phytic acid with average yield, and is susceptible to some RB races, RWW, and straighthead.
A 355 RIL F10−11 population derived from the cross of KBNTlpa × Zhe733 was recently released. Simple sequence repeat (SSR) markers were used to evaluate 269 RILs of this population. A
total of 107 polymorphic markers were mapped on all rice chromosomes representing a total of 1,016.3 cM of genetic distance.
Two hundred and thirty-five KBNTlpa × Zhe733 RILs (KZRILs) were clustered into seven groups based on allele frequencies of SSR markers. Twenty-three markers
(21.1%) on chromosomes 3, 6, 7, 9, and 11 were found to favor Zhe733 (χ
2 = 16.8−189.7 and P < 0.01) and five markers (4.6%) on chromosome 1 and 6 were found to favor KBNTlpa (χ
2 = 18.5−46.6 and P < 0.01). Marker segregations were observed to be normal for both parents except 26 (10.2%) KZRILs were found to skew toward
Zhe733 (χ
2 > 15.7 and P < 0.01). Furthermore, the average frequencies of heterozygosity and non-parental alleles per KZRIL were 1.3% (0.0−38.9%)
and 0.4% (0.0−15.0%), respectively. Thirteen heterozygous KZRILs were found at more than five markers loci and nine KZRILs
were found with more than five non-parental alleles representing 5.1 and 3.5% of 255 KZRILs. Overall, this KZRIL population
is a good population with relatively low frequencies of heterozygosity and non-parental alleles, and with relatively low percentages
of skewed markers and skewed KZRILs. The profiles of these SSR markers should facilitate molecular tagging critical genes
controlling yield, RB, RWW, and straighthead resistance. 相似文献