A chemosystematically significant 6,8,11-trihydroxygermacrane derivative from the New Zealand Apiaceae Anistome pilifera

Roots of Anisotome pilifera yielded typical Apiaceae compounds 6,7-dimethoxy-coumarin 1 and falcarindiol 2, plus the irregular diterpenes anisotomenoic acid 3 and anisotomene alcohol 4. The new germacrane derivative 8-O-senecioyl-6β,8α,11-trihydroxygermacra-1(10)E,4E-diene 5 was also isolated and the structure established by means of high resolution mass spectrometry and 1-D and 2-D NMR spectroscopy. Distribution and chemosystematic significance of 6,8-dihydroxygermacra-1(10)E,4E-dienes and 6,8,11-trihydroxygermacra-1(10)E,4E-dienes are discussed. Additionally, leaves of A. pilifera yielded chlorogenic acid 6 and high amounts of luteolin 7-O-α- -rhamnosyl(1→6)-β- -glucoside 7.     

Breeding and recruitment in a population of the New Zealand starfish Stichaster australis (Verrill)

The annual reproductive cycle of the New Zealand starfish Stichaster australis (Verrill) was determined at Maori Bay on the west coast of Auckland. S. australis has a clearly defined summer breeding season, closely repeated from year to year. Changes in the gonad shown by histological sections confirmed this cycle.S. australis juveniles reared in the laboratory were maintained on Mesophyllum insigne (Foslie) Adey substrata and the growth rates and feeding behaviour of individual starfish were determined. Settlement on the shore was from May to July each year. When the time of spawning is considered this implies a planktotrophic larval life of ≈ 6 months. This is considerably longer than laboratory studies on larval development would suggest.Growth of yearly settlement cohorts on a nursery site on the shore used in conjunction with laboratory results gave a fairly clear picture of growth after settlement. Growth rates followed a typical sigmoid curve, growth being slow initially and becoming more rapid later. The numbers of juveniles recruited to nursery areas vary from year to year but mortality following settlement appears to be low. It was found that juvenile Stichaster australis graze Mesophyllum insigne exclusively until they reach ≈ 0.8 cm in diameter (7–8 months old) when they may occasionally predate juvenile Perna canaliculus (Gmelin). The incidence of carnivorous feeding gradually increases until juveniles are ≈ 2.0–2.5 cm in diameter (15–18 months old) by which time they are exclusively carnivorous on small P. canaliculus. As growth continues juvenile starfish gradually migrate from nursery areas to adjacent reefs where there are dense beds of adult P. canaliculus. Starfish of this species become sexually mature when they reach ≈ 5–8 cm in diameter.     

Domoic acid production by Pseudo-nitzschia australis and Pseudo-nitzschia calliantha isolated from North Chile

The morphology and toxicity of the four ubiquitous species belonging to the genus Pseudo-nitzschia found in mixed blooms of phytoplankton from northern Chilean waters were studied. The phytoplankton samples and cultures obtained were identified by scanning electron microscopy, revealing the presence of Pseudo-nitzschia australis, P. calliantha, P. pseudodelicatissima and P. subfraudulenta. This is the first report of P. calliantha in northern Chile. Toxin analyses using the LC–MS method confirmed the presence of domoic acid in P. australis and P. calliantha. Domoic acid was not detected in cultures of P. subfraudulenta. This study therefore confirms P. australis and P. calliantha as an unequivocal source of domoic acid in Chilean waters. P. australis is probably the most important producer of amnesic shellfish toxin in view of its domoic acid content. However, more research is needed to evaluate the potential for toxin production in P. pseudodelicatissima.     

First artificial hybrid of the eel species Anguilla australis and Anguilla anguilla

Background  

Studies on artificial hybridization of different Anguilla species were conducted recently, i.e. female A. australis with male A. dieffenbachii, and female A. japonica with male A. anguilla. The existence of these artificial hybrids was however not demonstrated by independent genetic methods. Two species - A. anguilla and A. australis - that are phylogenetically close but have different sexual maturation times (12-25 weeks and 6-8 weeks, respectively), were expected to produce favourable hybrids for reproduction studies.     

Pectenotoxin and okadaic acid-based toxin profiles in Dinophysis acuta and Dinophysis acuminata from New Zealand

The major pectenotoxin and okadaic acid group toxins in Dinophysis acuta and Dinophysis acuminata cell concentrates, collected from various locations around the coast of the South Island of New Zealand (NZ), were determined by liquid chromatography–tandem mass spectrometry (LC–MS/MS). PTX2 and PTX11 were the major polyether toxins in all Dinophysis spp. cell concentrates. D. acuta contained PTX11 and PTX2 at concentrations of 4.7–64.6 and 32.5–107.5 pg per cell, respectively. The amounts of PTX11 and PTX2 in D. acuminata were much lower at 0.4–2.1 and 2.4–25.8 pg per cell, respectively. PTX seco acids comprised only 4% of the total PTX content of both D. acuta and D. acuminata. D. acuta contained low levels of OA (0.8–2.7 pg per cell) but specimens from the South Island west coast also contained up to 10 times higher levels of OA esters (7.0–10.2 pg per cell). Esterified forms of OA were not observed in D. acuta specimens from the Marlborough Sounds. D. acuta did not contain any DTX1 though all D. acuminata specimens contained DTX1 at levels of 0.1–2.4 pg per cell. DTX2 was not present in any New Zealand Dinophysis spp. specimens. Although the total toxin content varied spatially and temporally, the relative proportions of the various toxins in different specimens from the same location appeared to be relatively stable. The total PTX/total OA ratios in different isolates of D. acuta were very similar (mean±S.E.: 14.9±1.9), although the Marlborough Sounds D. acuminata isolates had a higher total PTX/total OA ratio (mean±S.E.: 22.7±2.4) than the Akaroa Harbour isolates (8.0). No evidence of azaspiracids were detected in these specimens. These results show that the LC–MS/MS monitoring of plankton for PTX group toxins (e.g. PTX2) and their derivatives (e.g. PTX2 seco acid) may provide a sensitive, semi-quantitative, indicator of the presence of more cryptic OA group toxins (e.g. OA esters).     

种间竞争对香蒲与芦苇生长的影响

为了探究种间竞争对香蒲（Typha domingensis）与芦苇（Phragmites australis）生长的影响,利用根系分隔盆栽试验研究了3种不同分隔方式条件下香蒲与芦苇的种间竞争特性,包括塑料膜分隔（根系完全分隔,无相互作用,无物质交换）、尼龙网分隔（根系部分分隔,无相互作用,有物质交换）和不分隔（根系完全相互作用,有物质交换）,分析了香蒲与芦苇根系形态和地上部生长的变化,探究香蒲与芦苇种间竞争的差异。结果发现（1）在尼龙网分隔和不分隔处理中芦苇具有明显的劣势。与塑料膜分隔处理相比,芦苇的总生物量、植株密度在尼龙网分隔和不分隔处理中分别减少了39.14%、49.41%和82.08%、79.22%,总根长、总根表面积、总根体积分别减少了40.53%、44.84%、62.52%和85.7%、82.45%、89.67%,且均具有极显著差异（P<0.01）;根系分隔方式也影响芦苇的株高、茎粗和叶片数,表现为不分隔 > 塑料膜分隔 > 尼龙网分隔。（2）与塑料膜分隔处理相比,香蒲总生物量在尼龙网分隔和不分隔中虽有增加,但差异不显著,植株密度和株高在尼龙网分隔和不分隔处理中都有增加且具有显著差异（P<0.05）,其总根长、总根表面积、总根体积在尼龙网分隔中分别增加了57.93%、26.5%、8.04%,但在不分隔处理中分别减少了11.57%、14.92%、11.39%（P<0.05）,虽然根系的相互作用对香蒲根系的生长具有促进作用,但植物种间根系相互作用越强,对两者的生长越不利。（3）在不同的分隔方式中,芦苇与香蒲间也存在明显变化。在不分隔处理中,香蒲的生物量和植株密度是芦苇的1.7倍和6.74倍,与塑料膜分隔处理相比增加了6倍,表明芦苇与香蒲根系的完全相互作用,显著削减了芦苇的繁殖生长,增加了香蒲的根系分蘖。（4）通过种间相互作用强度（RII值）分析也表明,尼龙网分隔和不分隔处理下芦苇表现为抑制作用（RII值为负值）,香蒲表现为促进作用（RII值为正值）。香蒲与芦苇互作对芦苇具有抑制作用,说明种间相互作用是能改变植物的适应性和植物群落的繁殖,同时也表明植物根系不仅在吸收土壤中的水和养分中起着关键作用,在种间关系中也起着重要作用。因此利用种间竞争控制植物生长,可以为保护生物多样性和生态系统的功能提供有效的技术支撑。     

新西兰银杏种质资源研究

新西兰位于南半球太平洋南部,介于南极洲和赤道之间,是目前为止南半球唯一一个将银杏作为产业来发展的国家。银杏在新西兰已有100多年的栽培历史,其南岛和北岛的各个城市和地区均栽植有银杏,但主要用作庭院、公园、街道绿化树种零星种植,直到21世纪初才开始被作为一种产业来发展。通过对新西兰的Auckland,Wellington,Hamilton,Hastings等主要城市的银杏种质资源进行广泛调查和定点观测,结果只发现有梅核类、佛指类、马铃类、园子类等四种类型。种核也较小,最大的为2.15g,最小的仅1.44g。本文主要报道了银杏在新西兰的栽培历史、生物学特性、种质资源及发展现状等,以期为中新两国开展在银杏方面的合作提供相关信息。     

Climatic relationships of some New Zealand forest tree species

Abstract. A dataset of some 10 000 plots was used to describe the climatic relationships of 33 widespread New Zealand tree species. Estimates of mean annual temperature, temperature seasonality, mean annual solar radiation, and moisture balance were derived from mathematical surfaces fitted to climate station data. Plots were also categorized into five lithological classes and three drainage classes. Generalized additive models were used to examine species/environment relationships. Mean annual temperature and mean annual solar radiation are most strongly correlated with current tree distributions, followed by moisture balance, temperature seasonality, lithology, and drainage. Most broad-leaved tree species other than Nothofagus spp. reach their greatest levels of occurrence in warm, moist environments with high solar radiation. In contrast, Nothofagus spp. generally reach their greatest levels of occurrence in cooler and/or lower insolation environments, and all have lower levels of occurrence on rhyolitic substrates which have resulted from large-scale geomorphic disturbance, mostly over the past few thousand years. Although coniferous species have widely differing climatic optima, many are biased towards lithological classes characterized either by large-scale geomorphic disturbance or harsh edaphic conditions. The relevance of these results to particular synecological questions is briefly discussed. Continuing adjustments in the range of slow-dispersing Nothofagus spp. are strongly suggested, and the climatic suitability of extensive rhyolitic basins in the central North Island, from which these species are largely absent, is confirmed.     

中国长足兰属(兰科)一新记录

报道了中国兰科植物一新记录, 即筒距长足兰[Pteroceras teres （Blume） Holttum], 并提供了描述与图片。该种与滇南长足兰[P. compressum （Blume） Holttum]相似, 但以花序轴圆柱形; 花黄色, 螺旋状排列; 距的先端囊状, 两侧压扁并多少扭转等特征与之区别。     

A new microsporidium from the oyster Ostrea lutaria in New Zealand

Microsporidium rapuae n. sp. (Microsporida) forms cysts within the connective tissue surrounding the gut epithelium of the oyster Ostrea lutaria. Except for encapsulation of the cysts by fibroblasts no pathogenic effects were observed. Each cyst contained a large number of spores possessing long well-developed polar filaments. This is the third Microspora recorded from Bivalvia (Mollusca), and the first which does not belong to the family Chytridiopsidae (Minisporida).     

城隍竹——福建竹亚科一新种

报道了竹亚科（Bambusoideae）少穗竹属（Oligostachyum Z.P.Wang et G.H.Ye）一新种——城隍竹（O. heterophyllum M.M.Lin）。该新种分布于我国福建西部,它与糙花少穗竹[O.scabriflorum（McClure） Z.P.Wang et G.H.Ye]相似或近缘,但秆小,直径不超过1.5 cm;秆箨淡紫绿色,背面具有瘤基刺毛,无斑点,无白粉,亦无焦边,基部密被细刚毛;箨片直立,基部不收缩;箨舌淡禾秆色;叶鞘被细微柔毛而与后者相区别。     

Nitrogenous preference of toxigenic Pseudo-nitzschia australis (Bacillariophyceae) from field and laboratory experiments

Field and laboratory experiments were designed to determine the differential growth and toxin response to inorganic and organic nitrogen additions in Pseudo-nitzschia spp. Nitrogen enrichments of 50 μM nitrate (KNO₃), 10 μM ammonium (NH₄Cl), 20 μM urea and a control (no addition) were carried out in separate carboys with seawater collected from the mouth of the San Francisco Bay (Bolinas Bay), an area characterized by high concentrations of macronutrients and iron. All treatments showed significant increases in biomass, with chlorophyll a peaking on days 4–5 for all treatments except urea, which maintained exponential growth through the termination of the experiment. Pseudo-nitzschia australis Frenguelli abundance was 10³ cells l⁻¹ at the start of the experiment and increased by an order of magnitude by day 2. Particulate domoic acid (pDA) was initially low but detectable (0.15 μg l⁻¹), and increased throughout exponential and stationary phases across all treatments. At the termination of the experiment, the urea treatment produced more than double the amount of pDA (9.39 μg l⁻¹) than that produced by the nitrate treatment (4.26 μg l⁻¹) and triple that of the control and ammonium treatments (1.36 μg l⁻¹ and 2.64 μg l⁻¹, respectively). The mean specific growth rates, calculated from increases in chlorophyll a and from cellular abundance of P. australis, were statistically similar across all treatments.These field results confirmed laboratory experiments conducted with a P. australis strain isolated from Monterey Bay, CA (isolate AU221-a) grown in artificial seawater enriched with 50 μM nitrate, 50 μM ammonium or 25 μM of urea as the sole nitrogen source. The exponential growth rate of P. australis was significantly slower for cells grown on urea (ca. 0.5 day⁻¹) compared to the cells grown on either nitrate or ammonium (ca. 0.9 day⁻¹). However the urea-grown cells produced more particulate and dissolved domoic acid (DA) than the ammonium- or nitrate-grown cells. The field and laboratory experiments demonstrate that P. australis is able to grow effectively on urea as the primary source of nitrogen and produced more pDA when grown on urea in both natural assemblages and unialgal cultures. These results suggest that the influence of urea from coastal runoff may prove to be more important in the development or maintenance of toxic blooms than previously thought, and that the source of nitrogen may be a determining factor in the relative toxicity of west coast blooms of P. australis.     

Sudden decline of cabbage tree (

Many cabbage trees (Cordyline australis) are dying throughout much of the North Island and the northern South Island of New Zealand. The symptomatology of those dying in urban environments is described, and is concluded to be consistent with the hypothesis that death is caused by a biotic agent entering through a leafy tuft of the branch system. This disease, which has been named Sudden Decline, usually leads to almost total defoliation of affected trees within 2-12 months. Disease incidence has increased linearly at about 11% per annum since 1987/88. Cultivated trees of C. kaspar; C. obtecta and various Cordyline hybrids have also been observed dying with Sudden Decline symptoms. Investigations ai:med at identifying the causal agent are described, and the hypothesis is advanced that a phytoplasma (mycoplasma-like organism or MLO) is the cause. Sudden Decline is contrasted with the widespread ill- health apparent in many pastoral populations of cabbage tree throughout the country. This Rural Decline is characterised by a general loss of branch and leaf vigour and occasional tree death. It is suggested that Rural Decline is a complex disease (decline disease) caused by various biotic and abiotic agents interacting with an ageing population growing in situations where regeneration is prevented. In many pastoral situations Sudden Decline is superimposed on Rural Decline. The ecological implications of Sudden Decline are discussed.     

Environmental correlates of tree alpha-diversity in New Zealand primary forests

Correlations between environment and tree alpha-diversity in New Zealand's primary forests were examined using an extensive quantitative dataset (14 540 plots). Generalised additive models were used to examine relationships between species richness and temperature, solar radiation, root-zone moisture deficit, relative humidity, lithology, drainage, and plot size for all trees (112 species), and separately for broadleaved trees (88 species), conifers (17), and the genus Nothofagus (4). Diversity both for all tree species and for broadleaved trees was predicted to be highest on sites with high temperatures, high solar radiation, and high soil and atmospheric moisture, and on sedimentary and basaltic substrates. Highest conifer diversity was predicted on sites with intermediate temperatures, low solar radiation, high root-zone and atmospheric moisture, and rhyolitic and Quaternary substrates, particularly where drainage was impeded. Highest Nothofagus diversity was predicted for sites combining low temperatures, high solar radiation, high root-zone moisture but low atmospheric moisture, and on granitic substrates. Differences in diversity between the species groups on different lithologies are interpreted as rejecting both the effects of variation in large-scale disturbance histories, and the effects of confounding environmental factors associated with particular substrates. There were also significant interactions between species groups: both broadleaved tree and conifer richness were predicted to be lower on sites where one or more Nothofagus spp. — all of which have marked patchiness in their distribution — are present. Although these results are consistent with the hypothesis that tree diversity is highest on sites conducive to high productivity, history is also indicated as an important determinant of tree diversity in New Zealand.     

Aromatic components of the leaves of the New Zealand lemonwood tree Pittosporum eugenioides

The major aromatic components of the essential leaf oil of the New Zealand lemonwood tree Pittosporum eugenioides are octyl acetate (33%), terpinen-4-ol (13%), decanol (6%) and (Z)-hex-3-enol (5%). These products are responsible for the characteristic Citrus-like aroma which is detected when the leaves are crushed, a phenomenon which provided the species with its common name. The major component of the oil, octyl acetate is also an abundant component of the essential oils of Heracleum and Boswellia species.     

鳞网衣属1中国新记录种

通过对鳞网衣属地衣形态和化学的研究,并结合核基因ITS序列的系统发育分析,报道了采自中国秦岭山区鳞网衣属1中国新记录种——球鳞网衣(新拟)[Psora globifera(Ach.)A.Massal.]。其识别特征为地衣体由密集、重叠鳞片组成,边缘常上翘,具有光泽,无粉霜,老鳞片上表面常具裂纹;子囊盘微凸至半球形,单一或数个簇生。该研究提供了该种基于中国标本的详细描述,并与相似种进行了比较。