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991.
通过对合肥市房地产价格现状的调查与分析,本文认为合肥房地产价格总体呈上涨的趋势,但增幅上可能趋缓;只有政府各单位部门多方面的努力和合作,才会使合肥房价更加合理,房产市场更加有序。  相似文献   
992.
Journal of Plant Diseases and Protection - Chickpea Ascochyta blight caused by Didymella rabiei is one of the most important fungal diseases affecting yield and seed quality negatively in Turkey....  相似文献   
993.
California privet (Ligustrum ovalifolium Hassk.) plants exhibiting leaf yellowing, witches’ broom, dieback and decline symptoms were observed for two years (2010–2011) in three gardens at Adana region (Turkey). DNA isolated from symptomatic and healthy plants was used to amplify 16S rDNA fragments by direct and nested-PCR. Phytoplasmas were detected in 21 symptomatic plants, out of 30 samples collected, whilst no PCR amplifications were obtained from asymptomatic plants. BLAST analysis of the 16S rDNA showed that the phytoplasma found in L. ovalifolium from Turkey, denoted as Turkish Ligustrum witches’ broom phytoplasma (TuLiWB), most closely resembled members of group 16SrII (peanut witches’ broom group) and shared up to 92 % sequence identity. Based on in silico 16S rDNA RFLP analysis and automated calculation of the pattern similarity coefficient, TuLiWB showed molecular characteristics different from all previously described phytoplasma species to represent a new taxon. Similar indication also emerged from the phylogenetic tree which allocated it in a novel discrete subclade within the phytoplasma clade. This is the first report on the presence of a phytoplasma affecting L. ovalifolium and whether this novel phytoplasma is the same agent reported as a mycoplasma-like organism (MLO) and associated with witches’ broom disease of Ligustrum in Korea (1989) is yet to be determined.  相似文献   
994.
Fig mosaic virus (FMV), which was described recently, is the only characterized causal agent of fig mosaic disease (FMD). It has six RNA segments and belongs to the Bunyaviridae family. In order to determine the genetic diversity of Turkish FMV isolates, the most common fig cultivars showing FMD symptoms were collected from different fig-growing provinces of Turkey. Nucleoprotein (Np) and Glycoprotein (Gp) gene-specific primers of FMV were used for RT-PCR analysis. According to RT-PCR results, 71 of 90 samples from 20 different cultivars and unknown fig seedlings were found to be infected by FMV. Among them, 41 isolates were sequenced and subjected to phylogenetic analyses based on the partial Gp and Np sequences at the amino acid level by the neighbor-joining method. The isolates showed more than 80% identity with reference FMV isolates (Acc. nos. FM991954.1 and FM864225.2). Based on phylogenetic analysis, the sequences clustered into two main groups for Np and Gp regions. Significant relationships between FMV isolates based on geographic origin and cultivars were not observed.  相似文献   
995.
多功能夹心肥料块养分释放特性研究   总被引:1,自引:1,他引:0  
通过室内模拟淋溶实验,对3种多功能夹心肥料块淋溶液中N、P、K进行测定分析。结果表明:(1)多功能夹心肥料块养分N、K累积淋溶曲线均呈"S"型变化,养分P呈持续平缓上升变化;(2)多功能夹心肥料块养分N、P、K淋溶速度明显低于对照处理,其N、K释放高峰期比对照迟缓,P与对照相当;(3)3种肥料块外包被对N、P、K素的缓释作用分别为树叶>牛粪>草炭、牛粪=树叶>草炭、树叶>牛粪>草炭。  相似文献   
996.
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998.
1. The objective of the study was to investigate the effects of breeder age and egg weight on hatching performance and morphological changes in segments of the small intestine of broiler chicks during a 21 h hatch window.

2. Eggs from Ross broiler breeder flocks aged 29 (young) and 48 weeks (old) were classified as light (LE) or heavy (HE) and incubated at the same conditions. At 475 h of incubation, eggs were checked every 3 h to determine time of external pipping and hatching. The first 42 chicks to emerge from each group were weighed and chick length was measured and 14 chicks from each group were sampled to collect residual yolk and intestine segments. The rest of chicks were placed back in the incubator and chick weight and length were measured individually at 9, 15 and 21 h after chicks hatched. At the end of 21 h, 14 chicks from each group were sampled again and the same procedure was followed.

3. The HE chicks pipped and hatched later than LE, regardless of breeder age. From hatch to the end of the hatch window, chick weight, but not yolk-free chick weight, gradually reduced. Relative residual yolk weight of chicks from both egg weights was similar at hatch, however, yolk sac utilisation was higher for LE chicks during the 21 h post-hatch period. At hatch, jejunum and ileum villus development was very similar for HE and LE chicks but greater development was observed for villus area with an increase in the jejunum villus length, width and goblet cell numbers in HE chicks.

4. The longest jejunum villus and the widest duodenum and jejunum villus were obtained for HE chicks from old breeders indicating that HE chicks from old breeders would have a greater surface area for nutrient absorption.  相似文献   

999.
Water, Air, &; Soil Pollution - The solubility of the gypsum is generally very high in comparison to many other minerals. The surface and groundwater contacting gypsum formations can easily...  相似文献   
1000.
通过对青藏高原东缘甘南碌曲草地最具代表性的披碱草-矮嵩草草地,异针茅-结叶嵩草+密生苔草草地、金露梅-嵩草草地、藏嵩草+裸果扁穗苔草划地,珠芽蓼+线叶嵩草草地,高山柳-嵩草草地,窄叶鲜卑花-嵩草草地和短柄草-密生苔草草地等8个草地类型嫩落植物量动态进行的连续3年定位监测,分析研究结果表明:地上植物量累积动态均符合Logistic曲线,衰减动态符合y=a b/x模式,6-7月是草群地上植物量累积的盛期,产量高峰出现在8月中旬;水、热是制约草地初级生产力的主导环境因子草群粗蛋白,粗脂肪,粗纤维含量与生长季节密切相关,DE、NND动态与地上植物量动态相似。  相似文献   
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