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1.
分析动物检疫工作现状及存在问题,提出加大经费、人力和物力投入,开展动物检疫法律法规宣传;加快动物检疫申报点建设,优化申报出证服务;做好官方兽医培训,加强检疫人员自身建设;建设畜禽集中交易市场,规范流通领域动物检疫工作等对策措施,为做好动物检疫工作提供参考。  相似文献   
2.
童年时,每到冬季,吃菜便成为困扰人们的大问题,可以长时间存储的大白菜顺理成章地成为每个家庭的当家菜。  相似文献   
3.
绿化苗木在引进、生产和管理中,不正常地发黄、焦枯、落叶,甚至死亡的主要原因包括:水分、空气湿度、土壤酸碱度、营养元素、病虫害、光照、温度及空气污染等因素。针对不同原因采取相应的防治措施。  相似文献   
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土地资源对于一个国家来说是不可或缺的资源,其管理直接影响到人民的生活,所以,其土地方面的管理是不容忽视的。近年来,国家在土地管理上遇到了瓶颈,在其管理措施以及格局等问题上出现了一些新问题。这些问题的出现直接影响国家对土地管理的效率,土地资源的合理利用情况也不容乐观。  相似文献   
6.
为了解芒果、荔枝、龙眼和柑橘四种果树花期蓟马发生种类,对广西境内上述4种果树主产区花期蓟马进行了采集调查。结果表明,4种果树花期分别采集到蓟马6848头、4078头、4427头和3790头,经形态特征结合分子生物学手段鉴定,共有12种蓟马,隶属于锯尾亚目(Terebrantia)蓟马科(Thripidae)5属10种和管尾亚目(Tubulifera)管蓟马科(Phlaeothripidae)1属2种。其中芒果花12种,荔枝花5种,龙眼花6种和柑橘花7种。黄胸蓟马T. hawaiiensis在调查的4种果树花期蓟马中均为优势种,占比分别为38.38%,69.10%,51.66%和48.23%。本研究初步对广西4种主要果树花期蓟马种类组成进行了调查,确立了优势种,为今后蓟马的有效防治提供理论参考。  相似文献   
7.
Improving Drought Tolerance of Rice by Designed QTL Pyramiding   总被引:4,自引:0,他引:4  
Drought is the most important factor limiting rice yields in the rainfed areas of Asia. To overcome the problem, we developed a new strategy 'designed QTL pyramiding' to more efficiently develop drought tolerant (DT) rice cultivars. In the first phase of this strategy, we developed large numbers of introgression lines (ILs) in elite backgrounds using backcross (BC) breeding, each of which carries multiple genomic segments for improved DT from a known donor. Then, we genotyped all ILs with SSR markers to track the genomewide pattern of introgression in the DT ILs of 16 BC populations derived from crosses between 2 recipients (IR64 and Teqing) and four different donors. X^2 tests and linkage disequilibrium analyses of introgression in the DT ILs revealed significant frequency shifts at many loci across the genome and non-random associations at the multilocus level as a result of selection for DT in the ILs, which led us to the discovery of putative genetic networks underlying DT in the ILs. The networks each containing all DT loci detected in ILs from a BC population showed some interesting features.  相似文献   
8.
The modem crop scientist has a large amount of available nucleotide sequence information to identify genes of potential agronomic importance. Using reverse genetic approaches, specific genes can be disrupted, and hypotheses regarding gene function directly tested in vivo. Although a number of reverse genetic methods have been introduced, many are limited in application because they are organism-specific, expensive, transgenic, or only transiently disrupt gene function. However, traditional mutagenesis using chemical mutagens has been widely used as a forward genetics strategy to create many new crop plant varieties at relatively low cost. Mutagens such as ethyl methanesulphonate (EMS) cause stable point mutations and thus produce an allelic series of truncation and missense changes that can provide a range of phenotypes (Greene et al., 2003). TILLING (targeting induced local lesions IN genomes) is a high-throughput reverse genetic strategy that combines traditional mutagenesis and SNP discovery methods (Colbert et al., 2001; McCallum et al., 2000). To identify mutations, target regions of-l.5 kb are amplified with fluorescently labeled gene specific primers. Heteroduplexes are then formed between wild-type and mutant strands, mismatches are cleaved by incubation with a single-strand specific nuclease,  相似文献   
9.
Development of cytoplasmic male sterile (CMS) lines with elongated uppermost internode (EUI) trait provides a genetic option to eliminate the use of GA3 in hybrid rice. During the past two decades, extensive work has been carried out on the subject that resulted in identification of several mutants with EUI trait for use in developing cytoplasmic/thermo-sensitive genic male-sterile lines with complete panicle exsertion (Okuno and Kawai, 1978; Rutger and Carnahan, 1981; Shen et al., 1987; Yang et al., 2000; 2002; Gangashetti et al., 2004). Two recessive genes (eui-1 and eui-2) mapped on chromosome 5 and 10 respectively have so far been reported to control the internode elongation in rice (Librojo and Khush, 1986; Yang et al., 2001; Ma et al., 2004). Considerable progress has been made in China in exploiting 'eur gene for development of hybrid rice parental lines (Yang et al., 2000; 2002; Zhang et al., 2002).  相似文献   
10.
Among the most important Mediterranean annual crops, durum wheat is widely grown in drought-prone areas. Therefore, improving water-use efficiency (WUE) of durum wheat represents a major breeding goal. IDu-WUE (Improving Durum wheat for Water Use Efficiency and yield stability through physiological and molecular approaches) is a collaborative project among public and private research centres in Italy, Spain and WANA (West Asia and North Africa) countries (Morocco, Tunisia, Syria and Lebanon) funded by the European Union aimed at investigating the genetic variation for WUE and yield stability in durum wheat grown in Mediterranean droughtprone areas. During the first year of the project, a number of morpho-physiological traits (e.g. early vigour, flowering time, leaf rolling, number of fertile tillers, etc.), WUE, WUE-related traits (e.g. carbon isotope discrimination, canopy temperature, chlorophyll fluorescence, etc.), yield and its components have been investigated in a RIL population (249 lines) and a collection of ca. 190 durum wheat accessions characterized by a high level of linkage disequilibrium (Maccaferri et al., 2005),  相似文献   
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