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91.
西双版纳地区引种的澳洲坚果抗寒性   总被引:2,自引:1,他引:2  
以3年生无性繁殖澳洲坚果10个品种的幼苗为材料.采用电导法和全株冰冻测试法测定西双版纳引种的10个澳洲坚果品种叶片的抗寒力变化.结果表明:10个澳洲坚果品种抗寒力(半致死温度)介于-0.72~2.36℃之间,H2和HY属于低温敏感性相对较弱的L类型,抗寒力较强;HAES900、A16和Special抗寒力较弱,属于低温敏感性较强的H类型;D4、OC、HAES816、A4和D等品种属于抗寒力中等的M类型.  相似文献   
92.
某地一头犬长期消瘦,在一次出现场回来后突然发病,经临床和血液检查分析,确诊为附红细胞体感染,经及时治疗,该犬已痊愈。现将诊疗经过报道如下:  相似文献   
93.
针对黄淮海平原典型中低产土壤砂姜黑土黏粒含量较高,土壤有效水分库容较低,严重限制作物生产的现状,该文采用盆栽试验,研究了不同外源改性物料的添加对土壤持水性能及小麦生理的影响,以期获得农田水分管理过程中的关键参数。盆栽试验设置常规氮磷钾(control,CK),常规氮磷钾配施下的添加秸秆(straw returning,SR)、秸秆碳(straw carbon,SC)和粉煤灰(fly ash,FA)处理,维持土壤相对含水率在80%,培育小麦至抽穗期,开展为期10 d的干旱胁迫试验。结果显示SR和SC处理提高了土壤持水能力,且处理间的差异较小;FA处理因其表面富含大量疏水性结晶矿物,土壤相对含水率下降较快,迟效水含量显著低于其余处理,但土壤速效水含量显著提高。不同改性措施均有提高小麦叶片相对含水率,减轻干旱胁迫的趋势,但在极端干旱胁迫下,FA处理叶片相对含水率不仅明显低于其余处理,且作物体内积累大量丙二醛、过氧化氢等有害物质。田间管理中砂姜黑土相对含水率应维持在38%(SR)、36.5%(SC)和24.5%(FA)以上,当土壤相对含水率低于30.78%(SC)、28.43%(SR)和22.5%(FA)时将会对作物生理产生不可逆的伤害。鉴于秸秆优良的保水性能,粉煤灰“富水,不保水”的特性,秸秆与粉煤灰的配合施用将利于砂姜黑土的改良。相关机制值得进一步研究。  相似文献   
94.
This study was designed to examine the effects of glycinin on growth, digestive ability, immune responses, antioxidant capacity and gene expression levels of golden crucian carp. Golden crucian carp were fed diets containing glycinin at 0, 30, 60, 90 and 120 g/kg, respectively, for 8 weeks. Body weight, weight gain percentage, specific growth rate and feed efficiency ratio were negatively related to the content of glycinin in diet. Activities of protease, acid phosphatase, alkaline phosphatase, lysozyme in hepatopancreas, and activities of catalase, glutathione peroxidase, superoxide dismutase, and total antioxidant capacity in the proximal intestine, mid intestine, distal intestine and hepatopancreas were negatively related to the content of glycinin in diet, whereas malondialdehyde in proximal intestine, mid intestine, distal intestine and hepatopancreas increased directly with the content of glycinin in diet. Furthermore, the relative expressions of TNF‐α and IL‐1β in proximal intestine, mid intestine and distal intestine increased directly with the content of glycinin in diet, whereas the relative expressions of TNF‐α and IL‐1β in hepatopancreas were negatively related to the content of glycinin in diets. The relative expressions of IL‐10 in proximal intestine, mid intestine, distal intestine and hepatopancreas all were negatively related to the content of glycinin in diets. In conclusion, reductions in growth, immunity and antioxidant capacity, intestine inflammation with dysfunction of digestive system occurred in golden crucian carp that fed a diet containing glycinin at 30 g/kg or higher after 8 weeks.  相似文献   
95.
HHNBV是1993年中国对虾暴发性流行病的主要病原之一。从纯化的病毒中提取DNA,用EcoRl限制性内切酶酶切成DNA片段,与PUC18体外重组,建立HHNBVDNA文库。从中筛选出三个重组质粒(5#、8#、9#),它们所插入的片段大小分别为:2.8Kb、0.8Kb、1.6Kb,它们分别用光敏生物素标记成探针,与感染HHNBV的病虾DNA呈阳性反应,以此利用制备的HHNBVDNA探针的高敏感性和特异性来检测虾病。  相似文献   
96.
本实验采用显微微量注射方法,交羊生长激素基因导入中轻地虾受精卵,受精卵发育到蚤状幼体第三期后采样检测。PCR检测结果表明:7个样品共93尾幼体,有3个样品呈出阳性信号,基因转移比率至少在3%以上。同时斑点杂交结果也证明有两个明显阳性斑点。  相似文献   
97.
The effects of starvation on biochemical composition and gametogenesis were investigated in the Pacific oyster Crassostrea gigas. Histological analysis, combined with oocyte examination and measurements of protein, glycogen and lipid levels and RNA/DNA ratio from gonad, adductor muscle and mantle tissue of each sex were performed. In the starved groups, C. gigas showed gonad development, but the progress was delayed during the experiment. Glycogen was the first substrate used by C. gigas for dealing with lack of food. While glycogen was rapidly consumed, protein and lipid contents decreased gradually. A decrease in the RNA/DNA ratio in the starved groups in all the body components was found during starvation, illustrating that RNA/DNA ratio was a valid indicator of nutritional condition in C. gigas. A significant increase in water and ash contents and a corresponding decrease in condition index were observed in the starved groups, showing that the water and ash content and condition index were related to the usage of glycogen, lipid and protein reserves in body composition. During starvation, energy reserves were mobilized for survival and gonad development, but spawning was arrested. The information obtained in this study is useful for broodstock management in the Pacific oyster industry.  相似文献   
98.
选取线粒体细胞色素b (cytochrome b,Cyt b)基因序列作为分子标记,分析了中国沿海棘头梅童鱼(Collichthys lucidus)的种群遗传结构.2019年9-11月在中国沿海9个采样点共采集棘头梅童鱼342尾,共检测到174个单倍型.通过构建单倍型网络连接图和单倍型进化树发现,棘头梅童鱼可分为北方...  相似文献   
99.
The Apostichopus japonicus is a valuable aquaculture species in China. In this study, 51 single nucleotide polymorphisms (SNPs) were identified from expressed sequence tags of sea cucumber using high‐resolution melting. The average observed heterozygosity (Ho) and expected heterozygosity (He) were 0.2462 and 0.2897, respectively. Thirty‐two of these loci were used for estimating the genetic similarity and variation between the five hatchery stocks from China and two wild stocks from Japan. No significant differences in Ho or He were observed between the wild and hatchery populations. The pairwise Fst (which ranged from 0.0119 to 0.0236) and the genetic identity (which varied from 0.9802 to 0.9915) showed no significant differentiation between the wild and cultured stocks. The analysis of molecular variance indicated the source of variation was at the level of “within the populations.” The information on the genetic variation and differentiation in cultured and wild populations of A. japonicus obtained in this study is useful for setting up suitable guidelines for founding and maintaining of cultured stocks and for future genetic improvement by selective breeding.  相似文献   
100.
指出了水质评价是进行水环境容量计算和实施水污染控制规划的重要基础。应用模糊神经网络原理,以某企业污水处理站的检验数据为依据,选择3个评价参数,使用MATLAB函数工具箱编程,建立了T—S模型,经过仿真得出评价结果,研究表明:该方法能正确评价水质的样本,具有较好地客观性和预测性。  相似文献   
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