Isolation,Identification and Analysis of Serotype and Antibiotic Susceptibility of Pathogenic Salmonella from Chickens

To investigate the situations of predominant strain and antibiotic resistance of pathogenic Salmonella from chickens in Guangxi Zhuang Autonomous region, Salmonella was pre-enriched and isolated from tissues of clinical suspected chickens, and the Salmonella isolates were identified by biochemical test using ID 32E System for the identification of Enterobacteriaceae of VITEK System ATB Expression, serotypes were determined by slid agglutination test, antibiotic susceptibility was analyzed by ATB VET Susceptibility Test Strip of Enterobacteriaceae antibiotics.The results showed that 34 Salmonella strains were obtained from 310 clinical samples, of which 1 strain belonged to A serogroup, 1 to C2 serogroup, 15 to B serogroup, 14 to D serogroup and 3 to untyped serogroup, and S.typhimurium of B serogroup and S.pullorum of D serogroup were the predominant serotypes.All Salmonella isolates were sensitive to meropenem, imipenem, spectinomycine and apramycine, and the resistance rates to chloramphenicol, kanamycine and gentamicine were less than 10%, and the resistance rates to amoxicillin, streptomycine, flumequine, oxolinique, sulfamethizol, tetracycline and nitrofurantoine ranged between 50% and 90%, while the resistance rates to penicilline, oxacilline, fusidique, rifampicine and metronidazole reached to 100%.The results indicated that the serotype distribution of pathogenic Salmonella from chickens exhibited regional characteristics, and S.typhimurium and S.pullorum were the predominant serotypes in Guangxi Zhuang Autonomous region, and antibiotic resistance of Salmonella isolates was very serious which should be highly concerned.     

Cloning and Sequence Analysis of N and M Genes of Avian Infectious Bronchitis Virus Guangxi Strain

To investigate genetic variation of avian infectious bronchitis virus (IBV) in Guangxi province,one strain of IBV was isolated from chicken.Two pairs of primers for amplifying the N and M genes of IBV were designed according to the sequences in GenBank.The N and M genes of the strain were amplified by RT-PCR,and they were proved to be the N and M genes of IBV by cloning,sequencing and compared with reference IBV strains published in GenBank.The results showed that the N gene from the IBV isolate consisted of 1 230 bp,coding 409 amino acids.The M gene from the IBV isolate consisted of 678 bp,coding 225 amino acids.The sequence analysis of N gene showed that it shared 87.2% to 93.3% nucleotide homologies and 90.0% to 94.4% deduced amino acid sequence homologies with IBV strains from GenBank.The M gene sequence analysis showed that it shared 83.6% to 91.0% nucleotide homologies and 82.7% to 92.9% deduced amino acid sequence homologies.The phylogenetic tree analysis showed that it was closely related to BJ and LX4 strains,and were clustered into one group;But with the distant relatives from other strains of IBV.These results suggested that the isolate was a new variant of IBV.     

Bats as the main prey of wintering long‐eared owl (Asio otus) in Beijing: Integrating biodiversity protection and urban management

The loss of biodiversity from urbanized areas is a major environmental problem challenging policy‐makers throughout the world. Solutions to this problem are urgently required in China. We carried out a case study of wintering long‐eared owls (Asio otus) and their main prey to illustrate the negative effects of urbanization combined with ineffective conservation of biodiversity in Beijing. Field monitoring of owl numbers at two roosting sites from 2004 to 2012 showed that the owl population had fallen rapidly in metropolitan Beijing. Analysis of pellet contents identified only seven individuals of two species of shrew. The majority of mammalian prey comprised four bat and seven rodent species, making up 29.3% and 29.5% of the prey items, respectively. Prey composition varied significantly among years at the two sample sites. At the urban site the consumption of bats and rodents declined gradually over time, while predation on birds increased. In contrast, at the suburban site the prey composition showed an overall decrease in the number of bats, a sharp increase and a subsequent decrease in bird prey, and the number of rodent prey fell to a low point. Rapid development of real estate and inadequate greenfield management in city parks resulted in negative effects on the bird and small mammal habitat of urban areas in Beijing. We suggest that measures to conserve biodiversity should be integrated into future urban planning to maintain China's rich biodiversity while also achieving sustainable economic development.     

应对胶合板“双反”调查的分析及思考

我国与美国在林产品国际贸易上一直纠纷不断。继2006年美国对我国林产品进行"337"调查、2010年对我国复合地板"反倾销、反补贴"调查之后,2012年,美国几家胶合板企业联合向美商务部DOC递交了关于启动对中国出口美胶合板产品"反倾销、反补贴"调查的报告。中国林产工业协会及涉案企业经过1年多的努力应诉,终于在美国国际贸易委员会(ITC)终裁环节中获得胜利。围绕美国对我国胶合板产品"反倾销、反补贴"调查胜诉案例,全面分析了"双反"调查提出的背景,简述了我国对胶合板"双反"调查的应诉情况,系统总结了应对"双反"胜诉的原因、获得的经验、产生的影响。并对今后面临问题所应采取的措施进行了深入思考。     

化学除草剂在育苗生产中的应用

采用果尔、除草醚和扑草净三种除草剂分别对落叶松、樟子松和云杉当年播种育苗进行化学除草对比试验,试验共分三次进行,其中出苗前一次、苗期两次,每次设30个样方,5个重复.试验结果表明,出苗前用药效果最好,灭草率果尔为97.6％、除草醚为92.6％、扑草净为94％;苗期两次试验的除草效果分别为:果尔93.6％和89％、除草醚86.3％和83.2％、扑草净91.4％和86.7％;采用化学除草与采用人工除草相比,可分别降低成本81.5％、76.7％和79.7％.     

下辽河平原潮棕壤撂荒地和人工林N2O、CH4排放研究

采用静态箱(暗箱)气相色谱法对下辽河平原潮棕壤撂荒地和人工林N2O、CH4排放进行了为期1年的原位测量,同时测量了土壤温湿度、气温,土壤NO3-N、NH4 -N含量等相关因子.结果表明,在观测期间内人工林地土壤的N2O排放通量明显高于撂荒地.撂荒地是大气CH4的源,而人工林则是CH4的汇.对人工林的观测结果表明,N2哦O排放与CH4排放之间存在负相关关系(R2=-0.351,p＜0.05,n=36);而撂荒地两种气体排放之间无明显相关关系.N2O排放通量和温度变化有很好的相关性.当土壤含水量在200 g/kg以上时,土壤含水量与CH4气体排放具有较好的正相关关系.     

加工番茄系统抗性诱导促生菌的筛选鉴定及其促生防病效果

【目的】 筛选具有诱导番茄系统抗性的促生菌并验证其对加工番茄早疫病、灰霉病的防效,为新疆加工番茄病害的生物防治提供理论依据和菌种资源。【方法】 采用稀释涂布法,分离番茄等作物的根部土壤细菌,以无菌生理盐水和稀释至10⁴倍数未接菌的NB培养基为空白对照,利用发芽实验初筛加工番茄促生菌;用菌株发酵液灌根处理加工番茄幼苗,以清水处理为空白对照,测量叶片中茉莉酸含量,复筛系统抗性诱导菌株,分别挑战接种番茄早疫病、灰霉病病原菌,统计疫情指数和诱抗效果。测定菌株16S rDNA序列,初步进行菌种鉴定。【结果】 共分离到147株细菌,筛选得到19株显著(P<0.05)促进加工番茄种子萌发、增加根长的促生菌,有4株促生菌显著(P<0.05)提高加工番茄叶片中茉莉酸含量,防病验证最终得到3株能同时有效防治加工番茄早疫病、灰霉病的菌株,诱抗防效在27.59%~39.44%。菌株FY10、FY12、FY93鉴定为Bacillus atrophaeus,Pseudomonas wadenswilerensis和Bacillus pumilus。【结论】 获得3株具有系统抗性诱导功能且有效防治加工番茄早疫病、灰霉病的促生菌。     

暖温带马尾松茎干径向变化特征及其对环境因子的响应

探究短时间（月、日）尺度上马尾松生长动态变化及其与环境因子之间的关系,为理解和预测气候变暖对马尾松生长的影响提供科学依据。从2019年6月-2020年5月,通过树干径向生长测量仪（DENDROMETER）和小型气象站,对马尾松茎干年内径向变化和同期环境数据进行连续监测。结果表明:1)马尾松茎干径向日变化呈现昼缩夜胀的基本规律,马尾松茎干半径在8:00-16:00下降到最小值,16:00至次日8:00上升到最大值,年内径向变化范围为-54.4~38.1 μm。2)马尾松月累积茎干径向变化量存在2个峰值,分别出现在6月和9月,为943.3 μm和823.6 μm。3)在非生长季（11月至次年2月）,马尾松日径向变化量与土壤含水量、空气湿度、降水量存在正相关关系（P<0.05）,与VPD存在负相关关系（P<0.01）。在生长季初期（3-5月）,马尾松日径向变化量与空气温度、土壤温度和VPD呈极显著正相关（P<0.01）,与土壤含水量呈极显著负相关。但在生长季中后期（6-10月）,马尾松日径向变化量与空气温度、土壤温度和VPD的相关关系由正转负,与土壤含水量的相关关系由负转正。这种转变主要是因为生长季初期,较高的温度和土壤含水量有利于马尾松日径向变化量的增加,而生长季中后期,过高的温度和较低的土壤含水量则抑制马尾松日径向变化量的增加。研究结果有助于进一步了解暖温带马尾松树木茎干的径向变化及其对环境变化的响应特征,为判断马尾松未来的生长趋势提供科学依据。     

基于隶属函数法对花生综合品质评价初探

为科学评价和充分利用花生新品种,本研究运用隶属函数法对12个花生品种品质的5项主要指标进行了综合分析。结果表明,隶属函数值不低于对照‘花育33号’的品种有3个,分别是‘中花224’、‘云花1号’、‘花育9122’,这3个品种综合品质较优,适宜在北方地区种植推广。其中,‘中花224’油酸含量大于75%且O/L＞10,可作为优质高油酸花生种质资源利用;‘云花1号’粗蛋白含量相对较高,具有较好的营养品质,可作为优质鲜食花生品种;‘花育9122’含油量较高,可作为油用加工型花生品种。     

高配合力籼型光温敏核不育系6022S的选育与应用

6022S系安徽省农业科学院水稻研究所以1892S为母本,与6M022（3M178/9311 F₆）杂交、自交,经5年7代选择育成的籼型光温敏核不育系。该不育系株型紧凑,分蘖力强,抗倒伏性好,不育起点温度低,异交结实率高,配合力强。2019年8月通过安徽省农作物品种审定委员会的鉴定。6022S所配组合表现出熟期适中,株高较矮,粒型较好,抗倒伏,高产优质等特点。