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81.
[目的]了解新疆库米什一处金矿土壤可培养细菌的多样性及建立菌种资源库.[方法]采集库米什金矿土壤样品,采用两种不同培养基(LB,TSB)分离纯化细菌,对其进行形态观察(菌落及细胞)、生理测定、16SrDNA测序和系统进化分析.[结果]从两种培养基上总共得到50株细菌,根据基于16S rDNA的系统进化分析表明,50株菌分别属于3个大类群:厚壁菌门(Firmicutes ),放线菌门(Actinobacteria),γ-变形菌纲(γ-Proteobaeteria),12个属,30个分类单元.其中芽抱杆菌属(Bacillus)为优势细菌种群,占已测种群的63.3;.菌株L10-5与Bacillus foraminis (AJ717382)有96.463;的相似率,可能为潜在新种.[结论]库米什金矿土壤可培养细菌具有较高的多样性,存在潜在新菌种资源,值得进一步研究.  相似文献   
82.
比较了天然林和森林采伐区土壤理化性质,评价了森林采伐对土壤的影响。采集了自然林和邻近的采伐林地三个土层(表层、中层和底层)土壤,对其属性进行了调查。森林土壤颗粒大小分布无显著变化。森林表层土和中层土体积密度存在显著差异。林地内表层土和中层土壤pH、表层土有机质和中层土有效磷均显著高于采伐林地的值。两块林地内可交换Na+和阳离子交换能力没有变化。这些结果表明,两块林地内表层和亚表层土壤变化较明显。森林采伐降低土壤理化性质。  相似文献   
83.
Indigenous perennial grasses are widely distributed in the Arabian Peninsula. Their survival under limited rainfall and grazing suggests a potential role as grassland species and for rehabilitation of degraded rangelands. Forage productivity, seed production and water‐use efficiency (WUE) was determined over 2 years for four indigenous grasses: buffel grass (Cenchrus ciliaris L.), dakhna (Coelachyrum piercei Benth.), da’ay (Lasiurus scindicus Henr.) and tuman (Panicum turgidum Forssk.) together with one exotic species, rhodes grass (Chloris gayana Kunth) in the central region of the United Arab Emirates. Three irrigation treatments were used: R1 (1858–6758 m3 ha?1 year?1), R2 (929–3379 m3 ha?1 year?1) and R3 (464–1689 m3 ha?1 year?1). Buffel grass had the highest dry‐matter (DM) yield under all irrigation treatments. The average DM yield of buffel grass was 14·6 and 15·1 t ha?1 in the 2 years which was significantly higher than that for the other grasses with dakhna having the lowest DM yields. The WUE of 0·7 and 0·8 kg DM m?3 in the 2 years for buffel grass was significantly greater than for the other grasses. Buffel grass showed the highest increase in WUE in both years when the irrigation was reduced from treatment R1 to R3. The results suggest that the desert grasses of the Arabian Peninsula, such as buffel grass, could be useful grass species in reducing the use of scarce irrigation water provided that seed production can be increased.  相似文献   
84.
The aim of this study is to reveal the energy balance of walnut in Central Anatolian Region in Turkey. This study has been conducted at the walnut cultivating facilities during the 2014–2015 production season in K?r?ehir, Konya, Nev?ehir and Ni?de provinces of Central Anatolian Region in Turkey, where walnut cultivation is intense. In the study, a total of 28 walnut cultivation facilities, yielding walnut, have been selected through Neyman method and surveys and observations have been performed in these facilities. The agricultural input energies and output energies used in walnut cultivation have been calculated to define the energy use efficiency. According to the study findings, the energy inputs in walnut cultivation are calculated respectively 17,851.33?MJ ha?1 (74.40%) chemical fertilizer energy, 2229.87?MJ ha?1 (9.29%) fuel energy, 1640.64?MJ ha?1 (6.83%) irrigation water energy, 1539?MJ ha?1 (6.41%) machine energy, 508.02?MJ ha?1 (%2.11) chemical energy, 180.35?MJ ha?1 (0.75%) human labour energy and 43.33?MJ ha?1 (0.18%) farm manure energy. Production outputs have been calculated as 14,679.52?MJ ha?1. Following the energy calculations, the output/input ratio, specific energy, energy efficiency and net energy calculations have been calculated respectively as 0.61, 30.20?MJ kg?1, 0.03?kg MJ?1 and ?9313.02?MJ ha?1. Benefit-cost ratio was calculated as 1.88, by dividing the gross value of production by the total cost of production per hectare in walnut production.  相似文献   
85.
Sternbergia candida is an important endemic bulbous plant with beautiful white flowers. It grows on the rock slopes of Baba mountains under Lebanon Cedars in the Mugla province of Turkey with Mediterranean climate. The plant is vulnerable and endangered due to illegal collection for local and foreign flower industry. Fast developing tourism industry and rapid urbanization has also shown negative implications on its population. The study reports three years successful adaptation results of S. candida in the continental climate of Ankara in the Central Anatolia. Four groups of bulbs based on diameter (>2.45, 2.15–2.44, 1.85–2.14 and <1.84 cm) were collected from its natural habitat during March, April and May 1998 and were evaluated for frequency (%) of emergence, mean number of leaves per plant, mean plant height, frequency (%) of flowering, frequency (%) of fruit setting. mean number of bulbs per plant, and mean diameter (cm) of regenerated bulbs. All categories of bulbs could be multiplied and adapted successfully with variable frequency of fruit setting. However, the highest fruit set was recorded from 2.15–2.44 cm April collected bulbs. This indicated that the bulb diameter and collection time had clear implications on multiplication, propagation and adaptation of the plant.  相似文献   
86.

Background  

The data generated during a course of a biological experiment/study can be sometimes be massive and its management becomes quite critical for the success of the investigation undertaken. The accumulation and analysis of such large datasets often becomes tedious for biologists and lab technicians. Most of the current phenotype data acquisition management systems do not cater to the specialized needs of large-scale data analysis. The successful application of genomic tools/strategies to introduce desired traits in plants requires extensive and precise phenotyping of plant populations or gene bank material, thus necessitating an efficient data acquisition system.  相似文献   
87.
The aim of this study was to investigate fatty acid profiles of different shrimp species caught from deep water and shallow water. The shrimp species investigated in the study were Aristeus antennatus, Aristeomorpha foliacea, Plesionica martia, Parapenaeus longirostris, and Plesionica edwardsi from deep water; and Metapenaeus monoceros, Penaeus semisulcatus, Penaeus kerathurus, and Penaeus japonicus from shallow water.

Fatty acid composition of shrimps varied. The main fatty acids were C18:1n9, C16:0, C25:6n3, C22:5n3, and C18:0. Saturated, monounsaturated, and polyunsaturated fatty acid (PUFA) contents of P. longirostris, P. edwardsi, and M. monoceros were markedly different, respectively. The ratio of n6/n3 of the edible tissue of M. monoceros was found to be 0.795, whereas this value was 0.152 in A. foliacea. Among the species studied, the highest docosahexaenoic acid + eicosapentaenoic acid value was found for P. kerathurus. The levels of PUFAs of shallow water shrimps (ranging from 33.44 to 42.77%) were found to be higher than those of deep water shrimps (ranging from 29.68 to 33.95%). Marine animals in the upper water layers gain nutrition through phytoplankton which provides n-3 PUFA depending on solar energy. Shallow water shrimp species provide a satisfying amount of PUFA.  相似文献   
88.
The aim of this study was to investigate the effects of freezing and frozen storage on protein functionality and texture of squid (Loligo vulgaris), octopus (Octopus vulgaris), and cuttlefish (Sepia officinalis) muscles. Squid, octopus, and cuttlefish samples were cut into pieces of 4 × 4 cm. These pieces were packed in polyethylene bags. The bags were frozen in a blast freezer at ?45°C until the thermal center reached ?18°C. Frozen samples were stored in a deep freezer at ?18°C for 30 days. After freezing and during frozen storage, total soluble protein and water holding capacity decreased and total free amino acid and cooking loss increased in all cephalopod muscles. According to instrumental texture analysis results, freezing and frozen storage affected textural characteristics of squid and cuttlefish but not of octopus. Sensory hardness and chewiness values of all cephalopods increased after freezing, but elasticity values did not change. There were no significant differences between storage days in hardness values of squid and octopus. However, significant differences in hardness values of cuttlefish were observed between the 1st day of storage and the last day.  相似文献   
89.
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