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61.
To assess the differentiation of the chloroplast genome in wild and cultivated species of Raphanus , nucleotide sequence polymorphisms were investigated for approximately 2 kbp ranging from trnL (UAA) to psbG in R. raphanistrum and R. sativus . Eighteen plants of wild species, 10 Japanese wild radish plants ( R. sativus ), and 31 cultivated plants were used for sequence analysis. Intraspecific variations of the chloroplast genome were present both in wild and cultivated Raphanus . All three genes investigated ( trnL , trnF and ndhJ ) contained nucleotide substitutions within the genus. Whereas, larger numbers of mutations were observed in the intergenic regions. Using the detected variations, the 59 radish plants were classified into 11 haplotypes, seven of which were unique to wild species. Among the haplotypes, one type corresponded completely with the Ogura male sterile cytoplasm. All the cultivated radishes belonged to one of four types, of which three were also observed in Japanese wild radish. The haplotypes were classified into four groups by cluster analysis, and the distribution in the dendrogram confirmed that cultivated radish has multiple origins. On the other hand, the seven haplotypes uniquely observed in R. raphanistrum were considered as useful materials to provide genetic diversity of cytoplasm for breeding of cultivated radishes. 相似文献
62.
The effective competition is an effective organizational form of the industry in modem market economy. It is a form accompanied with large - scale production and vigor competition. The analysis of effective competition has been the focus that people have paid close attention to it very much all the time. It is a basis of industrial policy, on the basis of the former research, the aufhors bring out 9 indexes according to the actual situation of our country, then take automobile trade as an example, we analyze the automobile trade with principal component. 相似文献
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64.
选取黄土丘陵沟壑区纸坊沟小流域为研究区,利用高精度遥感影像(分辨率0.068 m)和DEM (分辨率0.34 m)数据,结合野外调查,对崩塌、滑塌、滑坡、脱落和陷穴等失稳体进行识别,通过统计学、敏感系数方法,利用识别失稳体数据,分析不同类型失稳体空间分布状况,定量研究不同类型失稳体的影响因子敏感程度,揭示不同类型失稳体的主控因子,进一步阐明流域坡体失稳体的空间分布规律和影响坡体稳定性的主控因子。结果表明:(1)利用高精度遥感影像,获取流域失稳体,主要是以小规模和浅层的脱落、崩塌和滑塌为主,三者面积合计为0.417 km2,占流域总面积的5.04%。(2)评价因子内部中,土壤母质的红黏土、土地利用的天然灌木林地和草地、地貌部位的沟坡、坡度>35°、地形起伏度为0.74~3.34 m是坡体失稳发生的高敏感区域,也是崩塌、滑塌、脱落和陷穴发育共有的敏感区域。(3)影响坡体稳定性主控因子权重由大到小为土壤母质、地形起伏度、坡度、土地利用和坡向。崩塌、滑塌和脱落的主控因子与整体坡体稳定性的主控因子相同,但因子内部权重存在差异。崩塌与整体坡体稳定性影响因子顺序分布一致。滑塌主控因子权重由大到小为土壤母质>地形起伏度=坡度>土地利用>坡向>地貌部位。脱落主控因子权重由大到小为土壤母质>土地利用>地形起伏度>坡度=坡向>地貌部位。滑坡的主控因子为坡度和地形起伏度。陷穴的主控因子权重由大到小为土壤母质>地形起伏度>坡度>坡向。 相似文献
65.
基于线性谱聚类的林地图像中枯死树监测 总被引:1,自引:0,他引:1
【目的】将基于线性谱聚类超像素的方法应用在森林病虫害防治领域,可智能监测无人机森林虫害图像中的枯死树,为森林有害生物的监测工作提供技术支撑。【方法】分别以湖北省受松材线虫与辽宁省受红脂大小蠹侵害的松林无人机图像为试验数据,首先使用线性谱聚类超像素分割算法将图像划分为多个超像素;然后基于枯死树木的颜色特征,初步提取可能为枯死树的超像素区域;最后基于枯死树木与其他干扰地物具有不同的纹理特征,计算超像素的区域密度和缝隙量,利用支持向量机对初步提取的超像素进行分类,从而检测出图像中的枯死树。【结果】基于线性谱聚类超像素和支持向量机的枯死树监测方法可有效排除与枯死树木颜色相近的其他干扰地物,较准确地提取出枯死树木。使用该方法与基于植被颜色指数的阈值分割方法、基于简单线性迭代聚类超像素和随机森林的方法,对35幅受灾松林无人机图像进行试验,并选用交并比、虚警率和漏检率3个评价指标对3种方法进行定量对比分析。结果表明,基于线性谱聚类超像素的方法监测出的枯死树区域最精确,其监测结果与人工检测结果的交并比均值大于58%,且虚警率和漏检率均优于另外2种方法。【结论】基于线性谱聚类超像素的枯死树监测方法能实现松林中枯死树的快速、准确检测及定位。 相似文献
66.
以ArcGIS 10.2.2浮动版为平台,结合实例阐述在宗地结构中用宗地编辑器分割宗地,从宗地结构中导出图层,将图层和从宗地结构中导出的图层加载到ArcMap内容列表中,在ArcMap内容列表中用裁剪面工具捕捉导出图层的端点、折点分割图层,实现林地面积精确分割。认为该方法在林业工作中是一种实用的方法。 相似文献
67.
68.
2010年春季以来,在辽西部分养羊户中的断奶羔羊及育成羊群中出现不明原因的死亡现象,经抗生素等药物进行常规治疗无效,死亡率达12%.临床症状为可视黏膜及皮肤重度黄染并排血红蛋白尿,最后因肝肾功能衰竭死亡;病理剖检变化为肝、肾变性坏死及实质性器官出血性变化为主.通过流行病学调查,并对病死羊进行病理剖检及对饲料真菌毒素的检... 相似文献
69.
Avilés-Nova F Espinoza-Ortega A Castelán-Ortega OA Arriaga-Jordán CM 《Tropical animal health and production》2008,40(7):509-515
Liveweight gain was evaluated in tropical Dorper X Pelibuey lambs under intensive continuous grazing of native grasslands dominated by Paspalum notatum (PN) or Axonopus compressus (AC) in the subtropics of Central Mexico. Two trials were undertaken. Trial 1 lasted 12 weeks with 10 lambs (initial weight 18 +/- 2.57 kg, 3 months old) per treatment in 2002, and Trial 2 for 13 weeks with 8 lambs (initial weight 24.0 +/- 2.0 kg, 4 months old) per treatment. Lambs were weighed once per week, and liveweight change was estimated by linear regression over day of the experiment, using individual regression coefficients as unbiased estimates of daily liveweight change; analysed in a random block design. Lambs on Trial 1 gained 0.061 kg/lamb/day on PN and 0.047 kg/lamb/day on AC (P > 0.05) at an overall mean stocking rate of 25 lambs/ha. In Trial 2, liveweight gain was significantly larger in PN (0.060 kg/lamb/day) than on AC (0.043 kg/lamb/day) (P < 0.05), at a mean stocking rate of 21.5 lambs/ha. It is concluded that intensive continuous grazing of native grasslands in the subtropics of the highlands of Central Mexico enables moderate liveweight gains for weaned lambs during the rainy season; with better results in grasslands dominated by Paspalum notatum. 相似文献
70.
Acacia etbaica Schweinf. and Dichrostachys cinerea (L.) Wight et Arn. are among the common woody browse plants that naturally grow in many arid and semi-arid rangelands in sub Saharan Africa. An experiment was conducted to compare the voluntary dry matter intake, body weight gain, nitrogen balance, carcass composition and sensory attributes of goats supplemented with different levels of A. etbaica and D. cinerea fruits. Average initial body weight of the goats was 20.4 kg (± 0.8SE) and received one of the following fruit supplementation regimes for 120 days (on body weight basis, n = 4 goats per group): (1) Control, no supplement; (2) 0.5% of A. etbaica; (3) 0.5% of D. cinerea; (4) 1.0% of A. etbaica; (5) 1.0% of D. cinerea; (6) 1.5% of A. etbaica; (7) 1.5% of D. cinerea. All groups were allowed to graze/browse during the day. Compared to A. etbaica, D. cinerea fruits contained higher amounts of crude protein (182 vs 135 g/kg DM), metabolizable energy (11 vs 8.4 MJ/kg DM), and in vitro dry matter digestibility coefficient (0.7 vs 0.6). The concentrations of acid detergent fiber (ADF), sulphuric acid solubulized lignin, and tannin (soluble and condensed) were lower (P < 0.05) in D. cinerea than in A. etbaica fruits. A. etbaica fruits, however, contained higher amounts of Na, K, Fe, and Zn concentrations than D. cinerea fruits. Dry matter intake was markedly higher in supplemented groups than in the control group without supplement. Similarly, body weight gain in the control group was negative and lower (P < 0.05) than any of the supplemented groups. During the course of the experimental period (120 days) the group placed in the 1.5% D. cinerea fruit diet gained 2.6 kg whereas the control group lost 2.0 kg. Thus, the difference between these two groups was 4.6 kg, which suggests about 22.5% increment of the goats' initial body weight. N retention was negative for the control group and varied little among the remaining treatment groups. Dressing percent increased with increased level of either type of fruit supplement, the highest (51.8%) being achieved at the 1.5% D. cinerea level. There was no difference in bone tissue across treatment groups. D. cinerea fruit intake also resulted in juicy/watery flavor and tender carcass. D. cinerea fruits appeared to have no adverse effects when included at the highest level (1.5%) and could be collected and stored as dry season supplement to smallholder goats. This study shows that poor farmers can increase goat performance substantially through supplement feeding with wild fruits. Areas in Ethiopia originally set aside for provision of ecological services and biodiversity protection can also be used for wild fruit production and feeding of small stock. The effect of increasing D. cinerea fruits above the 1.5% body weight level should be a focus of future investigation. Further work on deactivation mechanism of tannins is required for A. etbaica fruits included at levels higher than 1.0%. 相似文献