Mark–recapture of Cerambyx welensii in dehesa woodlands: dispersal behaviour,population density,and mass trapping efficiency with low trap densities

The longhorn beetle, Cerambyx welensii Küster (Coleoptera: Cerambycidae), is an emerging pest involved in oak decline episodes in dehesa open woodlands. Larvae are xylophagous and cause considerable physiological, mechanical, and structural damages to trees. Chemical and biological control are currently unsatisfactory. Recent research has shown that mass trapping with a high density of baited traps (40 traps ha^?1) could be useful to manage C. welensii populations, although such a trap density was too high to be cost‐effective. In this 2‐year study (2010–2011) we investigated with mark–recapture methods in a large plot (1) the flight dispersal behaviour, (2) the adult population density, and (3) the efficiency of mass trapping at two low trap densities (one or four traps ha^?1). Results indicated that many adults were sedentary (60%) but flying adults displayed a strong propensity to move, both sexes dispersing on average more than 200 m and one male and one female flying at least 540 and 349 m, respectively. Recapture rates were high (0.26–0.35) and population density was estimated to be 6–22 adults ha^?1 with maximum likelihood models. Trapping efficiency ranged 48–61% with no significant effect of trap density or year. We conclude that results were not satisfactory enough to recommend mass trapping with low trap densities as control method for C. welensii and that more research is still required on the technical, ecological, and behavioural factors affecting control efficiency.     

倒卵叶青冈——广西壳斗科一新记录种

报道了广西壳斗科植物一新记录种——倒卵叶青冈,并对倒卵叶青冈的形态进行了补充描述,同时对该种的生存现状进行评价,为这一物种的保护提供基础资料。     

Plant coexistence alters terpene emission and content of Mediterranean species

There is evidence that secondary metabolism may modulate plant interactions and is modified by different biotic stress agents, such as herbivores or pathogens. However, it is poorly understood whether secondary metabolism is altered during competition among plants. The intraspecific and interspecific coexistence of some Mediterranean potted seedlings, namely Rosmarinus officinalis, Pinus halepensis, Cistus albidus and Quercus coccifera was investigated through their terpene accumulation within leaves (except for Q. coccifera, a non-storing species) and terpene emissions (for all species). Competition had both positive and negative effects for both terpene emissions and content, depending on the species a seedling coexisted with. For R. officinalis, terpene concentrations (1.8-cineole and camphor) and terpene emissions (camphene, camphor and overall monoterpenes) were lower when the neighbour species was P. halepensis. For C. albidus, no changes were observed in its content, while the overall sesquiterpene emissions (70% of total emissions) were reduced in all competition conditions, except in intraspecific competition. In the case of P. halepensis, the highest terpene content occurred when it grew with C. albidus, and in intraspecific competition, while its emissions were reduced under these conditions. Only emissions of Q. coccifera showed no significant changes in the different competition treatments.     

壳斗演化的假说及分子系统学和化石证据

壳斗作为壳斗科Fagaceae的重要特征, 其起源、演化和多样性形成长期以来为系统学家们所关注, 有众多的观点和假说。本文在综合这些假说的基础上, 结合分子系统学和大化石证据, 讨论了壳斗演化的规律。研究结果支持壳斗具枝性性质, 来源于二歧聚伞花序最外侧小枝的假说。在比较3个壳斗演化模型的基础上, 根据4种分子系统关系的一致性重建了壳斗的演化历史: 壳斗是单系起源; 水青冈属的2果4裂瓣壳斗是最早分化的壳斗类型, 三棱栎型壳斗是较晚分化的类型; 并支持具有内裂瓣的金鳞果类型壳斗可能与其他横切面为圆形的壳斗有较近的共同祖先。这一结果也得到了多个大化石证据的支持。壳斗科多个分子系统关系的一致性和壳斗化石证据共同证实了壳斗演化的规律是从开裂向裂瓣融合、逐步简化、多向发展; 支持开裂壳斗、坚果三角形、较小、具棱或狭翅是祖征, 融合壳斗、坚果圆形、较大、不具棱是衍征。这些结果为进一步探索壳斗科的演化历史和系统发育提供了新的证据。     

Study on the Convergent Passages of Water Conducting Elements in Secondary Xylem of Fagaceae

Structural variations in the convergent passages of water conducting elements were described in secondary xylem of 70 species of Fagaceae. Two types of water conducting systems were recognized on the ground of water-flow directions. The convergent passages of the longitudinal system mainly exhibited in the forms as perforations between the ends of Vessel elements, lateral wall pitting between the lateral walls of vessel elements, pitting be-tween vessel elements and imperforate tracheary elements, and pitting between imperforate tracheary elements. The convergent passages in the transverse system consisted of pitting between vessel elements and ray cells, pitting between imperforated tracheary elements and ray cells and simple pitting between ray cells. In addition, the roles of vasicentric tracheids and broad rays played in terms of conducting effectiveness and efficiency as proposed by Zimmermann were discussed.     

The Pollen Morphology in Relation to the Taxonomy and Phylogeny of Fagaceae

The present paper deals with the pollen morphology of 103 species belonging to sixgenera-Castanea, Castanopsis, Lithocarpus, Quercus, Fagus and Trigonobalanus in threesubfamilies-Castaneoideae, Quercoideae and Fagoideae. All pollen grains were examinedunder light microscope and scanning electron microscope, and those of some species were ex-amined under transmission electron microscope. The results may be summarised as follows:1. Pollen morphology of Fagaceae, seems to support division of the family into threesubfamilies. Fagoideae, Castaneoideae and Quercoideae.2. Four types of pollen grains are recognized in Fagaceae:1) Fagus-type (representative genus: Fagus): pollen granis are oblate-sphaeroidal,(31.5-39.9) x (35.7 46.2) μm in size, 3(-4)-colporate, peritreme or goniotreme, granulate-ornate under LM., granulate or verrucate under SEM.2) Trigonobalanus-type (T. doichangensis): pollen grains are suboblate-sphaeroidal,(23.1-29.4) ×(25.2-29.4) μm in size, 3-colporate, goniotreme, obscurely granulate-ornateunder LM, densely granulate or verrucate under SEM.3) Quercus-type (Quercus): pollen grains are subspheroidal-subprolate, (21-44.3)× (16.8-39.9) μm in size. 3-colporoidate (-3-colpate), peritreme, crassgranulate or finely-gra-nulate under LM, tuberculate verrucate or spinate under SEM.4) Castanea-type (including Castanea, Castanopsis, Lithocarpus): Pollen grains areprolate-supraprolate, (14.7-23.1)×(10.5-16.8)μm in size; 3-colporate, peritreme, obscu-rely ornate or subpsilate, under LM, rugulose, striate-rugulate or crass-striate under SEM.3. Pollen grains of Cyclobalanopsis age very similar to those of Quercus, and there-fore we support the treatment of Cyclobalanopsis as a subgenus of Quercus.4. On the basis of shape, type of aperture and exine structure, pollen of Trigonobalanusis distinguishable from those of the other genera in Fagaceae and it may be a new type of Fagaceae;5. On the basis of pollen morphology, morphological characters and geological stratification a scheme of phylogeny of Fagaceae is here presented.     

南水青冈属及壳斗科其他属花粉壁超微结构比较研究

对主要分布于南美和新西兰的南水青冈属Nothofagus 花粉外壁的超微结构进行了观察和研究, 同时与壳斗科其他属花粉外壁的结构进行比较,结果表明,南水青冈属花粉外壁的厚度、结构、萌发孔类 型以及花粉外壁表面的纹饰与壳斗科其他属花粉外壁的超微结构存在明显差别。主要表现为：南水青 冈属花粉外壁的柱状层和内层发育差,为颗粒状;基层和覆盖层无分化结构;覆盖层上为刺状纹饰;萌发 孔为5～8沟。壳斗科其他属花粉外壁的小柱发育好,形成明显的柱状层;覆盖层和基层常具一定的结 构;花粉表面较光滑,或为波状、颗粒或瘤状纹饰;内层发育较好;多数花粉具3孔沟,少数为3沟或3拟 孔沟。本研究认为南水青冈属花粉外壁的结构属于较原始类型,支持kuprianova等将南水青冈属独立为南壳斗科。     

Clonal population structure and genetic variation in sand-shinnery oak,Quercus havardii (Fagaceae)

We investigated clonal population structure and genetic variation in Quercus havardii (sand-shinnery oak), a deciduous rhizomatous shrub that dominates vegetation by forming uninterrupted expanses of ground cover over sandy deposits on the plains of western Texas, western Oklahoma, and eastern New Mexico. Isozyme electrophoresis (15 loci coding 11 enzymes) was used to recognize and map clones arrayed in a 2000-m transect (50-m sample intervals) and a 200 × 190 m grid (10-m sample intervals). Ninety-four clones were discovered, 38 in the transect and 56 in the grid, resulting in an estimated density of ～15 clones per hectare. Clones varied greatly in size (～100-7000 m), shape, and degree of fragmentation. The larger clones possessed massive interiors free of intergrowth by other clones, while the smaller clones varied in degree of intergrowth. The population maintained substantial levels of genetic variation (P = 60%, A = 2.5, H(exp) = 0.289) comparable to values obtained for other Quercus spp. and for other long-lived perennials. The population was outcrossing as evidenced by conformance of most loci to Hardy-Weinberg expected genotype proportions, although exceptions indicated a limited degree of population substructuring. These data indicate that despite apparent reproduction primarily through vegetative means, Q. havardii possesses conventional attributes of a sexual population.