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31.
香菇数量性状的相关性分析和主成分分析   总被引:9,自引:0,他引:9  
对110个香菇杂交菌株16个数量性状进行表型、遗传和环境相关性分析及主成分分析。由分析结果可知,单菇鲜重与有关单菇的其他5个性状在表型、遗传和环境等3个方面都存在极显著的正相关,与菇数存在3种极显著的负相关,与CMC酶活性、木聚糖酶活性分别呈显著和极显著遗传负相关。鲜菇总重与出菇期和原基期呈极显著的表型和遗传负相关,与菇数、两种菌丝生长速度及菌盖厚度呈极显著的遗传正相关。结果表明,在香菇育种工作中,菌丝生长速度和酶活性,可以作为对单菇性状和鲜菇总重进行选择的间接指标之一。主成分分析结果表明,16个性状可以缩减为6个主成分,按方差贡献率大小分别命名为单菇、发育、产量、酶活、原基和转色因子,6个主成分的方差累积贡献率为80.75%。在香菇育种中,可以按照育种目标对上述主成分因子或其分量进行单独选择。  相似文献   
32.
迁徙水鸟保护对生物多样性保护具有重要意义。开展水鸟种群数量和幼鸟比例监测,对科学评估其种群变化趋势、制定长期保护策略具有重要价值。长江中下游湿地是东亚-澳大利西亚迁徙路线上重要的水鸟越冬区之一。本研究采用野外同步调查等方法对该区域87个湿地的亟需保护和具有代表性的10种大型越冬水鸟,其中雁形目6种,分别是鸿雁Anser cygnoides、豆雁A.fabalis、灰雁A.grus、白额雁A.albifrons、小白额雁A.erythropus和小天鹅Cygnus columbianus;鹤形目4种,分别是白鹤Leucogeranus leucogeranus、白枕鹤Antigone vipio、灰鹤Grus grus和白头鹤G.monacha,进行了长期监测(2003—2019年冬季),并结合相关文献,评估其种群变化趋势、幼鸟比例和死亡率。研究结果如下:(1)2005—2019年3种水鸟(豆雁、灰雁和灰鹤)的种群数量呈上升趋势,7种水鸟(鸿雁、白额雁、小白额雁、小天鹅、白鹤、白枕鹤和白头鹤)种群数量呈下降趋势;(2)种群趋势下降组(N=7)和上升组(N=3)的幼鸟比例均值在2016—2...  相似文献   
33.
调查湖北黄冈黄州龙王山渐尖毛蕨在不同生境条件下的种群密度和盖度。采用相邻格子法计算渐尖毛蕨种群分布的偏离系数,并进行t检验,判断种群分布类型;应用双项轨迹方差法分析种群格局规模。结果表明,渐尖毛蕨种群呈集群分布,形成的斑块直径大小约为3.0~3.5 m,且随着干扰的减少,斑块数目呈现少→多→少,其大小呈现大→小→大的变化趋势。  相似文献   
34.
For dendroclimatological Blue Intensity (BI) studies based on earlywood (EW) or latewood (LW) information, a demarcation between the two is necessary, which can be difficult to establish for species where the transition is subtle. Often, a percental value k is used that calculates an EW/LW boundary value for each tree ring individually based on the difference between maximum and minimum absorption. Several laboratories and authors have used different values for k (e.g. k = 30 % or k = 50 %), while wood anatomical and visual studies suggest that k is on the order of 80 %. Here, we test how different settings of k, and thus different definitions of the EW and LW proportions of a tree ring, influence the dendroclimatic potential of derived time series. To this end, we correlate instrumental temperature measurements with tree ring chronologies that are based on EW and LW information (e.g. EW absorption (EWBI), LW absorption (LWBI)), where the EW/LW proportion is varied by setting different values for k. The tree ring samples utilized are 30 cores of spruce (Picea abies) trees from a high-elevated site (ca. 1700 m a.s.l.) in the northern Alps, Austria. Overall, we achieve high correlations between temperature data and our tree ring chronologies. Regarding the stability of the climate signal under different k values, the results show that absorption intensity based parameters (ΔBI, EWBI, LWBI) are only mildly influenced by different settings of k, while width based parameters (EW width, LW width) show a larger dependence on k. LW width, for instance, was stronger correlated with temperature, the smaller the LW was chosen (and thus the higher k was set). Based on our results and the wood anatomical definition of the EW/LW boundary, we suggest that k = 80 % may be a good choice for future studies. However, since this is only a case study from one site, careful screening of the respective data set regarding an appropriate k value must accompany each dendroclimatological study.  相似文献   
35.
To investigate insecticide resistance and dynamic changes of carboxylesterase polymorphism in mosquitoes with time in the Culex pipiens complex (Diptera: Culicidae), nine field mosquito populations were collected in China. The resistance levels of fourth-instar larvae to organophosphate (dichlorvos, parathion, and chlorpyrifos), carbamate (fenobucarb and propoxur), and pyrethroid (permethrin, deltamethrin and tetramethrin) insecticides were determined by bioassay. Larvae had more resistance to organophosphate insecticides than to carbamate insecticides. A low but significant resistance was observed for carbamate insecticides. The resistance to pyrethroid insecticides varied from sensitive to high. Starch gel electrophoresis revealed the presence of the overproduced esterases B1, A2B2, A8B8, A9B9, B10 and A11B11. The frequency of each overproduced esterases varied depending on its regional localities. Compared with published surveys, the C. pipiens complex, which exhibited a high polymorphism of applied esterase alleles in China, showed dynamic evolution over time under local specific insecticide selection. The results are discussed in the context of recent alterations to insecticide campaigns, and in the evolution of resistance genes in Chinese C. pipiens populations.  相似文献   
36.
土荆芥提取物对玉米象的触杀与熏蒸活性   总被引:2,自引:0,他引:2  
测定了土荆芥(Chenopodium ambrosioidesL.)4种溶剂(100%乙醇、丙酮、乙酸乙酯和石油醚)提取物对玉米象Sitophilusz eamais Motschulsky的触杀和,蒸活性。4种溶剂提取物在6.494mg/cm2浓度下对玉米象的触杀效果:48h后100%乙醇提取物和石油醚提取物的校正死亡率均达100%;丙酮提取物次之,为92.31%;乙酸乙酯提取物最低,为64.10%,但72h后达94.17%。4种溶剂提取物对玉米象的,蒸活性:72h后0.50mg/mL浓度处理下校正死亡率为98.73%~100%。  相似文献   
37.
记述我国地谷蛾亚科Meessiinae1新纪录属——黑地谷蛾属Epactris Meyrick,1905及1新纪录种——短黑地谷蛾E.alcaea Meyrick,1924。首次记述了该属外生殖器特征,并研究和讨论了短黑地谷蛾的雌性外生殖器变异。研究标本保存在南开大学生命科学学院昆虫标本室。  相似文献   
38.
The effect of surfactants on fluorescein isothiocyanate (FITC)-bovine serum albumin (BSA)-hypochlorite (ClO(-)), FITC-human serum albumin (HSA)-ClO(-), FITC-ovoconalbumin (OVA)-ClO(-), FITC-hemoglobin (Hb)-ClO(-) systems were investigated with chemiluminescence method by the reversed phase flow injection. It was found that the chemiluminescence (CL) intensity of each system was increased greatly in the presence of cationic surfactants. Cethyltrimethylammonium bromide (CTAB) is the optimal surfactant of these systems. The optimal conditions of the CL reaction and the optimal concentration of CTAB were examined and the function of cationic surfactant CTAB on the CL reaction was also discussed.  相似文献   
39.
以甘蓝型油菜( Brassica napus L.)品种‘Westar’和‘Topas’为材料,通过超微结构观察和荧光定量PCR技术对油菜胚胎发育早期油体的发生、油体蛋白及脂肪酸合成转录因子基因的表达情况进行分析。结果显示:油体出现在油菜胚胎发育早期,在授粉9 ~ 11 d后(球形胚时期)的胚体和胚柄中均存在直径小于0. 5 μm的油体;荧光定量实验结果表明,除 BnCLO3 的表达量在整个胚胎发育阶段无明显变化外,其他油体蛋白基因 Oleosins 、 Steroleosins 和 BnCLO1 的表达量在心形胚时期就明显增多并持续增长;脂肪酸合成转录因子 BnLEC1 、 BnL1L 、 BnWRI1 和 BnFUS3 在胚胎发育阶段,基因表达规律均呈先上升再下降的趋势,但达到最高值的时间存在差异,其中 BnLEC1 最早, BnL1L 其次, BnWRI1 和 BnFUS3 较晚。研究结果表明甘蓝型油菜在球形胚时期出现油体,其结构蛋白和转录调控因子基因的表达自心形胚开始明显增多。  相似文献   
40.
《Phytomedicine》2014,21(12):1708-1716
PurposeAntrodia camphorata (AC), a highly valued polypore mushroom native only to Taiwan, has been traditionally used as a medicine for the treatment of food and drug intoxication, diarrhea, abdominal pain, hypertension, skin itching, and cancer. In this study, both of solid-state-cultured AC (S-AC) and wood-cultured AC (W-AC) were evaluated the anti-inflammatory effects on hyperoxia-induced lung injury in NF-κB-luciferase+/+ transgenic mice.MethodsThe homozygous transgenic mice (NF-κB-luciferase+/+) were randomly assigned to four groups for treatment (n = 6) including Normoxia/DMSO group, Hyperoxia/DMSO group, Hyperoxia/S-AC group, and Hyperoxia/W-AC group. After 72 h of hyperoxia, we examined the bioluminescence images, reactive oxygen species (ROS), the mRNA and protein expression levels of inflammation factors, and histopathological analyses of the lung tissues.ResultsHyperoxia-induced lung injury significantly increased the generation of ROS, the mRNA levels of IL-6, TNF-α, IL-1β and IL-8, and the protein expression levels of IKKα/β, iNOS and IL-6. Pulmonary edema and alveolar infiltration of neutrophils was also observed in the hyperoxia-induced lung tissue. However, treatment with either S-AC or W-AC obviously decreased hyperoxia-induced generation of ROS and the expression of IL-6, TNF-α, IL-1β, IL-8, IKKα/β and iNOS compared to hyperoxia treatment alone. Lung histopathology also showed that treatment with either S-AC or W-AC significantly reduced neutrophil infiltration and lung edema compared to treatment with hyperoxia treated alone. To find out their major compounds, eburicoic acid and dehydroeburicoic acid were both isolated and identified from S-AC and W-AC by using HPLC, MS, and NMR spectrometry.ConclusionsThese results demonstrated that methanolic extracts both of S-AC and W-AC have excellent anti-inflammatory activities and thus have great potential as a source for natural health products.  相似文献   
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