昆虫飞行能力研究进展

昆虫的迁飞导致害虫区域性大规模爆发,给农业带来极大的灾难。研究昆虫的飞行能力将为明确迁飞性昆虫的迁飞规律提供理论参考。本文综述分析了昆虫飞行能力的研究方法及应用范围,详细阐述了影响昆虫飞行能力的主要因素如自身个体间差异、环境、食物胁迫、振翅频率、生殖等及飞行对昆虫的影响,并就昆虫飞行能力研究中存在的问题及未来的研究方向进行了展望。     

真盐生植物盐地碱蓬根系边缘细胞在耐盐中的作用初探

以黄河三角洲潮间带盐地碱蓬种子生成的幼苗为材料,研究了NaCl胁迫对盐地碱蓬生长与根系边缘细胞的影响。盐地碱蓬的第一个边缘细胞几乎与根尖同步产生,当根长达到13mm时,边缘细胞数目达到最大值。NaCl胁迫抑制边缘细胞的活性,但低浓度的NaCl处理增加边缘细胞的数目。低浓度NaCl处理时果胶甲基酯酶（PME）的活性比对照有明显增加,超氧化物歧化酶（SOD）活性随着NaCl浓度的增加呈现先上升后下降的趋势,低浓度NaCl可以增加盐地碱蓬根内过氧化氢酶（CAT）的活性,NaCl处理时间和处理浓度都对过氧化物酶（POD）活性的影响不明显。这些结果表明,盐地碱蓬至少部分通过增加调控活性氧（ROS）水平增加PME活性及根系边缘细胞数目来抵抗NaCl胁迫。     

基于地统计学的黄土高寒区典型林地土壤水分盈亏状况研究

土壤水分是黄土高寒区水循环、地下水补给和植被恢复的关键因素,基于地统计学研究土壤水分空间分布及其盈亏状况,揭示林地土壤水分的空间分布规律、变异特征及空间结构,对于区域植被恢复具有重要价值。以大通县安门滩小流域人工林地作为研究对象,运用地统计学方法对其5月、7月和9月的土壤储水量、林地耗水量和土壤水分盈亏量进行综合分析。研究结果表明:(1)土壤储水量总体表现为9月5月7月,而林地耗水量为7月9月5月,5—7月绝大多数林地的土壤水分呈亏损状态,而7—9月所有林地土壤水分都得到了补充,总体来看,5—9月研究区多数林地的土壤水分有所盈余,土壤储水量、林地耗水量和土壤水分盈亏量均采用指数模型作为最优理论变异函数模型;(2)5月、7月和9月土壤储水量呈南高北低、西高东低的空间分异规律,且西南-东北方向变异较东南-西北方向剧烈;各月林地耗水量在西南-东北方向变异较东南-西北方向剧烈,总体表现为西南部区域低于东北部区域;在5—7月、7—9月和5—9月这三个时期内,土壤水分盈亏量的取值均呈现出东北部区域小于西南部区域的特点。综上,当地土壤水分状况与林地耗水量分布格局并不完全匹配,虽然绝大部分林分能够维持土壤水分收支平衡,但部分山脚处的青杨林地和中部区域的华北落叶松林地出现了土壤水分亏损的现象。为防止林地水分环境恶化,在之后黄土高寒区的植被建设过程中,应适当调整林分配置。     

Genome-wide association study of bronchial asthma in the Volga-Urals region of Russia

Bronchial asthma is a chronic inflammatory respiratory disease caused by a complex interaction of environmental influences and genetic susceptibility. The first genome-wide association study of bronchial asthma discovered a significant association between single nucleotide polymorphisms (SNPs) located within the genomic region 17q12-q21 and childhood bronchial asthma in individuals of European descent. This result was later replicated in a number of independent population samples of European and Asian origin. Here we report the results of the first genome-wide association study of bronchial asthma in the Volga-Urals region of Russia. The study involved 358 unrelated patients with physician-diagnosed bronchial asthma and 369 disease-free control subjects of different ethnicity (Russians, Tatars, and Bashkirs). DNA specimens were genotyped using an Illumina Human610 quad array as a part of the GABRIEL project (EC contract no. LSHB-CT-2006-018996). After QC filtering procedures, a final set of 550 915 SNPs genotyped in 330 patients and 348 controls was tested for association with bronchial asthma. Five markers on chromosome 17q12-21 showed significant association with bronchial asthma (p ≤ 4.79 × 10⁻⁷). The rs7216389 SNP located in GSDMB intron 1 showed the strongest evidence for association (p = 1.01 × 10⁻⁷). Association with childhood asthma (p = 1.97 × 10⁻⁶ for rs7216389) was stronger than with late-onset asthma (p = 1.8 × 10⁻⁴ for rs7216389). A replication study of three SNPs located within GSDMB confirmed association only with childhood asthma. In sum, these results suggest that genetic variants of 17q12–q21 play an important role in susceptibility to bronchial asthma in the Volga-Urals region of Russia.     

Coexistence of nitrifiers, denitrifiers and Anammox bacteria in a sequencing batch biofilm reactor as revealed by PCR-DGGE

Aims:  The bacterial diversity in a sequencing batch biofilm reactor (SBBR) treating landfill leachate was studied to explain the mechanism of nitrogen removal.
Methods and Results:  The total microbial DNA was extracted from samples collected from landfill leachate and biofilm of the reactor with the removal efficiencies of NH₄⁺-N higher than 97% and that of chemical oxygen demand (determined by K₂Cr₂O₇, COD_Cr) higher than 86%. Denaturing gradient gel electrophoresis (DGGE) fingerprints based on total community 16S rRNA genes were analyzed with statistical methods, and excised DNA bands were sequenced. The results of phylogenetic analyses revealed high diversity within the SBBR biofilm community, and DGGE banding patterns showed that the community structure in the biofilm remained stable during the running period.
Conclusions:  A coexistence of nitrifiers, including ammonia-oxidizing bacteria and nitrite-oxidizing bacteria, denitrifiers, including aerobic or anaerobic denitrifying bacteria and Anammox bacteria were detected, which might be the real matter of high removal efficiencies of NH₄⁺-N and COD_Cr in the reactor.
Significance and Impact of the Study:  The findings in this study indicated that PCR-DGGE analysis could be used for microbial community detection as prior method, and the SBBR technique could provide preferable growing environment for bacteria with N removal function.     

Identification of two markers linked to the sex locus in dioecious <Emphasis Type="Italic">Asparagus officinalis</Emphasis> plants

One hundred decamer primers of random-amplified polymorphic DNA were tested on dioecious Asparagus officinalis plants to identify sex-linked molecular markers. One primer (S368) produced two markers (S368-928 and S368-1178) in female plants. These two DNA markers were identified in 30 male and female plants, respectively, and a S368-928 marker was proved to be linked to the female sex locus. The female-linked S368-928 marker was sequenced and specific primers were synthesized to generate a 928 bp marker of sequence characterized amplified regions (SCAR) in female plants, SCAR₉₂₈. SCAR₉₂₈ could be used to correctly screen homozygous mm female plants of A. officinalis. However, results of Southern blot analysis suggest that the hybridization pattern of S368-928 was presented in both sex plants. This text was submitted by the authors in English.     

Comparison of methods for total community DNA extraction and purification from compost

The differences on DNA yield and purity of three different DNA extraction protocols were compared with regard to the use for PCR and other molecular analyses. Total DNA was extracted from compost by the three protocols, and then was purified by spin-bind cartridges after being precipitated by PEG8000. The detection performed on a nucleic acid and protein analyzer showed that all three methods produced high DNA yields. The agarose gel electrophoresis showed that the fragments of crude and purified DNA had a length of about 23 kb. A eubacterial 16S rRNA gene-targeted primer pair was used for PCR amplification, and full length 16S rDNAs were amplified from all the purified DNA samples. After being digested by restriction endonucleases, the restriction map of amplified rDNA showed identical genetic diversity. The products of PCR using primer pair GC341F and 907R were also used for denaturing gradient gel electrophoresis analysis. The results indicated that high-quality DNA was extracted from compost by the three protocols, and each of the protocols is adapted to extract microbial genome DNA from compost expediently and cheaply.     

核苷酸转换因子的特性及其在植物中的研究现状

热激蛋白HSP70是一类细胞必需的具有ATPase活性的分子伴侣。ADP的脱离是HSP70分子伴侣体系能够完成其功能循环的限速步骤,该反应步骤由核苷酸交换因子（NEFs）加速,因此,NEFs是HSP70分子伴侣体系中的一类关键辅助因子。本文总结了有关NEFs的研究成果以及植物NEFs的最新研究进展。     

B型酪氨酸激酶受体的轴浆转运

脑源性神经营养因子(brain-derived neurotrophic factor,BDNF)在发育及成熟的中枢神经系统(central nervoussystem,CNS)中起到举足轻重的调节作用,而其中绝大部分作用由其B型酪氨酸激酶受体(tyrosine kinase receptortype B,TrkB)介导,因此TrkB在神经元中的轴浆转运过程显得尤为重要。本文从动力蛋白、潜在调节分子、细胞骨架蛋白等方面对TrkB轴浆转运分子机制的研究进展进行综述,并就其进一步研究提出一系列的问题与展望。     

滑刃属一新种记述(滑刃目,滑刃科)

2002年从山东省乳山市牛筋草的根际土壤中发现滑刃属1新种,类刷尾滑刃线虫 Aphelenchoides parabrushmucronatus sp.nov,.该虫具有以下特征:雌虫虫体中等;唇区较高,缢缩明显;中食道球卵圆形;生殖系统发育良好,卵母细胞单列,受精囊和后阴子宫囊都含较大的圆形精子;雌虫尾圆柱形,尾端中间具有1试管刷状尾尖突.A.appendurus Singh,1967在形态上与新种相似,区别在于前者有两条侧线,虫体和口针更长,尾巴相对较短(L=720-880μm;stylet=16～17μm;tail=38.4μm).A.seiachicus Nesterov,1973在形态上也与新种相似,区别在于前者虫体更小,口针、尾巴更短(L=370-420μm;stylet=9.5μm;c'=3).