排序方式: 共有13条查询结果,搜索用时 0 毫秒
1.
2.
M. Ikram Khan Virginia Marroni Sandi Keenan Ian A. W. Scott Suvi L. H. Viljanen-Rollinson Simon Bulman 《European journal of plant pathology / European Foundation for Plant Pathology》2013,136(3):495-507
Botrytis spp. associated with neck rot disease were isolated from New Zealand onions. The fungi were identified using molecular sequences of the ribosomal internal transcribed spacer (ITS) and intergenic spacer (IGS) regions, and the glyceraldehyde-3-phosphate dehydrogenase (G3PDH) gene. Analyses of the sequences showed that the majority of the isolates gathered in 2005–07 were B. aclada. A new high resolution melting analysis (HRMA) assay was developed that allowed fast and simple discrimination between B. aclada and other Botrytis spp. causing onion neck rot in New Zealand. To further verify these results, Botrytis isolates from New Zealand onions, stored in the International Collection of Microorganisms from Plants (ICMP), were also examined. Only a single isolate from the ICMP collection was B. aclada while two isolates were B. byssoidea, one B. squamosa and another closely related to Botryotinia porri. Identification of the remaining Botrytis isolates was more difficult; while IGS and ITS sequences indicated a close relationship to B. allii or B. byssoidea, a previously unreported intron insertion was observed at the 3′ end of the ribosomal small subunit gene in these isolates. No evidence of heterogeneity was observed in the G3PDH gene sequences, as might have been expected of the allodiploid B. allii, but the G3PDH sequence ruled out B. byssoidea as the identity of these isolates. 相似文献
3.
For over a decade, molecular short standardised DNA fragments, termed DNA barcodes, have been developed for species discrimination around the world. As of 2010, the vast majority of barcoding research was biased toward particular taxonomic groups and geographic regions largely because researchers in developed countries were the ones with the resources and capacity to carry out such work. To rectify this, the International Barcode of Life Project was launched with the intent to extend the geographic and taxonomic coverage of the barcode reference library. South Africa committed to this mission in an attempt to catalogue all of its known biodiversity and, possibly, help identify new species. To date, approximately 48 000 South African faunal barcodes are housed in the Barcode of Life Data System (BOLD), which represent only 2.3% of all known South African animal species. Although insects are the best represented in absolute terms, with over 37 000 samples recorded, they are still grossly lacking with just over 1% representation. Much like the global trend, there is a general taxonomic bias, with fish, birds and mammals showing the greatest representation. Moreover, geographic bias is also present, with the Free State province particularly under-represented on BOLD, likely owing to limited human capacity. Although few studies have been published with respect to barcoding, the majority reveal that the cytochrome c oxidase 1 (CO1) gene, used in isolation or in conjunction with other molecular markers, can greatly benefit South African biodiversity research. Several limitations of DNA barcoding are discussed and recommendations specific to South Africa provided. 相似文献
4.
A survey of medicinal plants used by rural communities in the Bustillo Province of the Potosi Department in Bolivia is reported in this article. Fifty-six plant species belonging to 24 families and 46 different genera were included. Their botanical and vernacular names, plant part used, popular medicinal use, forms of preparation and applications of the herbal remedies are given. 相似文献
5.
6.
Paddy and Water Environment - SALIBU technology (rice ratooning modification) is an innovation in rice farming technology allowing ratoon crops to be harvested up to 3.5–4 times annually with... 相似文献
7.
剖腹产是奶牛发生难产时经徒手或器械仍无法助产而实施的一种外科助产手术。传统的卧式剖腹产手术由于在切开子宫拉出胎儿时难免有恶露顺势流入腹腔,虽经反复冲洗和抗炎处理,仍可能引发腹腔感染,影响奶牛康复甚至丧失生产能力而被迫淘汰。笔者从去年以来尝试站立式剖腹产手术3例均取得满意效果,其中2例已配受孕。现将第3例手术经过叙述如下。 相似文献
8.
Goat-keeping in Indonesia is characterized by a stagnant population, intensive production systems, production primarily by smallholders, and a strong product demand. Research is underway to identify production constraints under typical smallholder systems using a farming systems approach.Problem identification has focused on productivity problems and then breaking down the various sources of the productivity gap. Several productivity measures are reviewed and their usefulness for problem identification discussed. Smallholder survey data from selected locations in West Java are then used to identify productivity gaps existing between these farms, larger specialized farms and experiment stations. 相似文献
9.
10.
应用中分辨率遥感数据和地理信息系统改进森林材积和生物量评估策略(英文) 总被引:7,自引:0,他引:7
应用遥感技术、地理信息系统和野外观测数据,评估了热带森林环境下地上生物量和木材蓄积量。用于模拟森林属性的这些数据具有地理特异性和高度的不确定性,因此,这方面需要开展更多的研究工作。选取了16个试样地带1460个样地,测定树木胸径及其他用于评估生物量的其他森林属性。本实验在印尼加里曼丹东部的热带雨林开展。应用现有的胸径-生物量公式来评估地上生物量密度。估测值在研究区修正的GIS地图上重叠显示,计算各种地被物的生物量密度。用样品数据子集表达遥感方法来形成地上生物量和材积线性方程模型。皮尔森相关统计检验采用ETM条带反射率、植被指数、图像变化图层、主成分分析条带、缨帽变换、灰度共生矩阵纹理特征和DEM数据作为预报值。在显著的遥感数据中形成了两个线性模型。为了分析每块地被物总的生物量和材积量,对2000年到2003年卫星ETM图进行了预处理、最大似然估计法分类和主体分析过滤。遥感方法获得的结果表明:材积量为(158±16)m3·hm-2,地上生物量为(168±15)t·hm-2;而野外测定和地理信息系统估计的结果分别是材积量为(157±92)m3·hm-2、地上生物量为(167±94)t·hm-2。用多个瞬间ETM数据评估了从2000年到2003年间的生物量丰富度动态,结果发现这一时期总生物量呈略微的下降趋势。遥感技术评估的生物量丰富度低于地理信息系统和野外测定的结果。前一种测定方法估计2000年和2003年总生物量分别是10.47Gt和10.3Gt,而后一种则估计11.9Gt和11.6Gt。还发现,灰度共生矩阵纹理特征与材积量和生物量之间存在较强的相关性。图7表9参43。 相似文献