角倍蚜干母的刺探取食行为分析

本文采用EPG技术监测角倍蚜Schlechtendalia chinensis(Bell)干母在第一寄主植物盐肤木(Rhus chinensis Mill)上的取食行为.获得干母在盐肤木小叶及叶翅上的取食波形7个,分别为np、C(A+B+C)、pd、E1、E2、F、G波.对干母在盐肤木小叶或叶翅上的取食部位组织进行切片...     

中国对虾抗WSSV及其它经济性状的QTL定位初步研究

以中国对虾抗WSSV选育群体第四代雌虾和野生中国对虾雄虾为亲本,采用人工精荚移植方式产生F1代家系,家系内个体姊妹交获得R家系材料,42尾R家系个体采用口饲法进行WSSV（White Spot Syndrome Virus）攻毒实验,获得个体抗WSSV及其它相关数据。构建了中国对虾的AFLP（Amphfied Fragment Length Polymorphism）分子标记遗传连锁图谱。利用MAPMAKER／QTL1．1软件进行了中国对虾体长、全长、体重及抗WSSV性状的QTL（Quantitative TraitsLoci）定位分析,首次实现了中国对虾重要经济性状的QTL定位。在LOD值大于2．0的条件下,共检测到和体长相关的QTL位点1个,与全长相关的QTL位点2个,与体重相关的QTL位点2个,与抗WSSV性状相关的位点2个,分别位于3个连锁群上,位点变异解释率从26．6％-66．9％不等。在其中的1个连锁群上检测到了体重、全长和抗WSSV性状相关的三个QTL位点,1个连锁群上检测到了体重和抗WSSV性状相关的两个QTL位点,1个连锁群上检测到了全长和体长相关的两个QTL位点。表明在中国对虾在此生长阶段,抗WSSV性状和个体大小存在一定程度的正相关关系[动物学报54（6）：1075-1081,2008]。     

Trigonostemons G and H,dinorditerpenoid dimers with axially chiral biaryl linkage from Trigonostemon chinensis

Trigonostemons G and H, two novel dimeric dinorditerpenoids, were isolated from the stem barks of Trigonostemon chinensis. Their planar structures and relative configurations were established by extensive analysis of spectroscopic data. Trigonostemons G and H possess a homodimeric biaryl skeleton obtained from two rearranged chiral nonracemic abietane-type dinorditerpenes through an axially chiral biaryl 11,11′-linkage. Torsional scan and computation of the transition states were carried out to estimate the rotational energy barrier, and the axial chirality (aS) was determined by time-dependent density functional theory (TDDFT) electronic circular dichroism (ECD) calculations. The positive n-π* ECD transitions of the isolated carbonyl chromophore above 300 nm could be used to determine the central chirality of trigonostemon G independently by ECD calculations of the diastereomers.     

Responses of riparian trees to interannual variation in ground water depth in a semi-arid river basin

We investigated the physiological and growth responses of native (Populus fremontii S. Wats. and Salix gooddingii Ball) and exotic (Tamarix chinensis Lour.) riparian trees to ground water availability at the free‐flowing Hassayampa River, Arizona, during dry (1997) and wet (1998) years. In the drier year, all species experienced considerable water stress, as evidenced by low shoot water potentials, low leaf gas exchange rates and large amounts of canopy dieback. These parameters were significantly related to depth of ground water (DGW) in the native species, but not in T. chinensis, in 1997. Canopy dieback was greater in the native species than in T. chinensis when ground water was deep in 1997, and dieback increased rapidly at DGW > 2·5–3·0 m for the native species. Analysis of combined data from wet and dry years for T. chinensis tentatively suggests a similar physiological sensitivity to water availability and a similar DGW threshold for canopy dieback. In 1998, shoot water potential and leaf gas exchange rates were higher and canopy dieback was lower for all species because of increased water availability. However, T. chinensis showed a much larger increase in leaf gas exchange rates in the wet year than the native species. High leaf gas exchange rates, growth when water is abundant, drought tolerance and the maintenance of a viable canopy under dry conditions are characteristics that help explain the ability of T. chinensis to thrive in riparian ecosystems in the south‐western United States.     

黑胸散白蚁分离饲养补充型生殖蚁的产生及羽化分飞行为

对黑胸散白蚁Reticulitermes chinensis Snyder成熟群体进行室内自然条件分离饲养观察,结果表明:单品级分离群体和多品级分离群体均能产生补充型生殖蚁,产生补充型生殖蚁的概率与分离群体内的个体数量呈正相关关系,分离时间和气温对产生补充型生殖蚁的历期影响较大,1、4、6、9月分离的群体产生补充型生殖蚁的历期分别为78.50、46.00、32.17、26.00d,经分析差异显著(P<0.05)。分离群体能迅速产出有翅成虫羽化分飞,在分离后2年就可发育进入羽化分飞的成熟年龄,分离时间对产生羽化分飞的历期有一定影响,6月分离的多品级分离群体产生羽化分飞的历期平均为659.3d。单品级翅芽若蚁分离群体可产生羽化分飞,且存在反季节羽化现象。     

石香薷（唇形科）的胚胎学研究

石香薷(Mosla chinensis Buch.-Ham.ex Maxim.)花药壁发育属双子叶型。花药具4个小孢子囊;腺质绒毡层,细胞具2～4核,有3至数个核仁;初生造孢细胞直接行小孢子母细胞的功能,在小孢子囊中成单列。花粉母细胞减数分裂后胞质分裂为同时型;小孢子四分体呈四面体形,也有左右对称形,成熟花粉具2细胞。胚珠倒生,单珠被,薄珠心,大孢子四分体线形排列,功能性大孢子位于合点端,少数为合点端第二个细胞。胚囊发育属蓼型,珠孔区近卵圆形,比合点区稍短,合点区较狭窄。胚胎发生属柳叶菜型。细胞型胚乳,珠孔吸器为单孢3核,合点吸器为单孢2核。种子无胚乳,种皮由珠被发育。石香薷雌雄配子体的发育、胚胎发生及胚乳形成,与紫苏属的Perilla ocimoides几乎完全一致。不同点仅在于石香薷在2-细胞花粉时,药室内壁细胞切向伸长,壁尚未发生纤维状加厚(P.ocimoides药室内壁细胞径向伸长,胞壁纤维状加厚),珠孔吸器为单孢3核(P.ocimoides为单孢4核)。胚胎学显示石荠苎属与紫苏属有密切的亲缘关系。     

珠颈斑鸠繁殖期占据领域鸣声特征及行为

2003年4～6月,在四川省南充市通过野外观察、录音、室内计算机处理及声谱分析对珠颈斑鸠繁殖期占据领域鸣声特征及行为做了研究。结果表明：珠颈斑鸠有一般占据和召唤配偶共同占据两类鸣声,两类鸣声雌雄不同,但均由3音节组成;其鸣唱具有应答性,且每次在各栖位点的鸣唱顺序大致相同;日鸣唱频次变化大,具3个高峰期;繁殖各时期鸣唱频次变化亦大。     

宣黄连的生态学特征和栽培研究

宣黄连特指主产安徽的短萼黄连,宣黄连系安徽历史名药,由于长期的采集,资源已经极度枯竭。本文报道了宣黄连的生态学特征和栽培研究,研究表明,野生宣黄连种群主要分布在安徽皖南山区,有林下类型和溪边类型两种,其中以林下类型为主。对宣黄连的栽培结果表明,宣黄连最适宜在皖南山区生长,应建立种质苗圃以保护和繁育宣黄连。     

中华双腔吸虫精子发生的超微结构研究

应用透射电镜技术,研究中华双腔吸虫的精子发生,并与其它复殖吸虫进行比较,提出了复殖吸虫精子发生的一般过程,结果显示它与大多数复殖吸虫精子发生的超微结构相似,原始的精原细胞经过次有丝分裂,两次减数分裂成为精细胞,它经过分化,形态变化后成为成熟精子,精子形成共分为六个阶段。其中形成共分为六个阶段,其中有以下首次报道的特征,（１）中央胞持区的生长速度在开始时比鞭毛裂快;（２）在鞭毛与中央胞质区融合前,线     

濒危植物南方红豆杉濒危原因分析

南方红豆杉是我国第三纪孑遗特有树种,为国家1级濒危保护植物,主要分布于在长江流域、南岭山脉以及广东、广西、江西、河南、陕西、甘肃、台湾和山西等省（区）的山地。南方红豆杉分布区的生态环境特征是：热量充足,温暖潮湿。南方红豆杉濒危的主要原因有：（1）种子产生量少,萌发率和幼苗成活率较低（2）种群缺乏较强的竞争力,（3）地理分布的局限性,（4）对生境要求的特殊性和（5）人为破坏严重。此外,针对南方红豆杉濒危现状和原因,还提出了科学保护和可持续利用的对策。