Studies on Karyotype of Cephalanthera erecta and C. falcat

The present paper reports karyotype analysis of Cephalanthera erecta and C. falcata from Lushan, China. (1) The karyotype formula of C. erecta is 2n=34=10m+ 14sm+ 10st. C. falcata has two cytotypes: type A is 2n = 34 = 8m + 16sm + 10st, while type B is 2n = 34 = 8m + 22sm + 4st. The type B is a translocation homozygote derived from the type A by chromosomal structural reorganization, which involved a translocation between the short arms of the 1st pair of chromosomes and the long arms of the 3rd pair. The type B is similar to the type A in morphological characterissties. (2)In the light of Stebbins’ classification of karyotypic asymmetry, three karyotypes of C. erecta and C. falcata belong to “3C”. Such an asymmetrical karyotype in a primitive genus like Cephalanthera of Orchidaceae may be of great significancefor a discussion on evolution and deserves a further study.     

Leaf miners: The hidden herbivores

Leaf mining is a form of endophagous herbivory in which insect larvae live and feed within leaf tissue. In this review we discuss aspects of leaf miner ecology, and the current evidence for three hypotheses relating to the evolution of this feeding guild. We also present a summary of the literature coverage relating to these herbivores, which have been relatively poorly studied compared with insects that feed externally such as sap suckers and leaf chewers. The majority of published studies concern leaf miners from the northern hemisphere, with a general focus on those species considered to be agricultural, forestry or horticultural pests. In a more detailed case study, we examine aspects of leaf miner ecology of Australian species. At least 114 species have been recorded as leaf miners in Australia in four orders: Coleoptera, Lepidoptera, Diptera and Hymenoptera. Lepidoptera and Diptera are the most speciose orders of Australian leaf miners; Hymenoptera are represented by a single endemic genus and half of all coleopteran miners are species introduced for biological control. Both the known number of leaf‐mining species in Australia and the known number of hosts have increased in recent years following new targeted surveys. Leaf miners in Australia occur in many habitats and feed on a wide variety of host plants in at least 60 families although most individual species are monophagous. Although much of the research on leaf miners in Australia has focused on species that are commercially important pests or biological control agents, studies on fundamental aspects of leaf miner ecology are increasing. We identify a number of research questions aimed at better understanding the ecology of leaf miners in Australia and elsewhere.     

Oviposition response of scarabaeids: does ‘mother knows best’ about rainfall variability and soil moisture?

Abstract.  The effect of soil moisture on ovipositional preference is studied for four melolonthine scarabaeids, Holotrichia reynaudi , Holotrichia serrata and Dermolepida albohirtum , which are endemic to the semiarid tropics of India ( Holotrichia spp.) and Australia, and Heteronyx piceus , which is endemic to the temperate and subtropical regions of Australia. As predicted by the preference-performance hypothesis, the three tropically adapted species show little or no ovipositional preference for soil moistures between permanent wilting point (−1500 kPa) and field capacity (−10 kPa) under either choice or no-choice conditions in their endemic soils, whereas H.   piceus shows a clear preference to oviposit in drier soils (−1500 to −200 kPa). The ovipositional soil-moisture preferences of D.   albohirtum and H.   serrata are much narrower in geographically adjacent non-endemic soils (between −1500 to −200 kPa) than in their endemic soils. An analysis of daily rainfall determined the rainfall variability within the endemic areas of each species. The semiarid tropics are highly variable, with rainfall at the time of oviposition being a poor predictor of the future rain required for successful larval development, whereas the rainfall in the subtropics is much more reliable. The absence of a clearly preferred soil moisture for oviposition in the tropically adapted species appears to be a life-history strategy that allows these species to live in environments where rainfall is highly variable, and soil moisture at time of oviposition is a poor predictor of future environmental suitability for plant growth, and thus larval survival.     

Phylogenetic analyses suggest a hybrid origin of the figs (Moraceae: Ficus) that are endemic to the Ogasawara (Bonin) Islands, Japan

The Ogasawara Islands are oceanic islands and harbor a unique endemic flora. There are three fig species (Ficus boninsimae, F. nishimurae and F. iidaiana) endemic to the Ogasawara Islands, and these species have been considered to be closely related to Ficus erecta, and to have diverged within the islands. However, this hypothesis remains uncertain. To investigate this issue, we assessed the phylogenetic relationships of the Ogasawara figs and their close relatives occurring in Japan, Taiwan and South China based on six plastid genome regions, nuclear ITS region and two nuclear genes. The plastid genome-based tree indicated a close relationship between the Ogasawara figs and F. erecta, whereas some of the nuclear gene-based trees suggested this relationship was not so close. In addition, the phylogenetic analyses of the pollinating wasps associated with these fig species based on the nuclear 28S rRNA and mitochondrial cytB genes suggested that the fig-pollinating wasps of F. erecta are not sister to those of the Ogasawara figs These results suggest the occurrence of an early hybridization event(s) in the lineage leading to the Ogasawara figs.     

A new species of fern, genus Danaea (Marattiales: Marattiaceae) endemic to Costa Rica

Danaea tuomistoana A. Rojas (Marattiaceae) is described and illustrated as a new species endemic to Costa Rica; it differs from D. crispa Endres et Richb. by a truncate blade, and by the pinnae, which are 2/5-1/2 incised, cuneated at the base and with a flat margin. The range of D. erecta H. Tuomisto & R.C. Moran in Costa Rica is expanded with a new locality in Puntarenas (8 degrees 57'15" N-82 degrees 50'1" W, 1,500-1,580 masl).     

Commensalism used by freshwater crayfish species to survive drying in seasonal habitats

Abstract. Gramastacus insolitus is a very small non-burrowing Australian freshwater crayfish with a restricted distribution, occurring almost exclusively in seasonal habitats throughout its range. It is listed as a threatened species but its strategy for surviving dry periods was unknown. Eight seasonal surveys of crayfish distribution showed that members of G. insolitus were never found at sites that were outside the distribution of two larger burrowing freshwater crayfish species, Geocharax falcata and Cherax destructor. Excavation of 80 burrows of members of G. falcata and C. destructor in three different seasonal habitats in the Grampians National Park, Victoria, Australia, revealed that individuals of G. insolitus found refuge from drying by estivating in cracks and shallow depressions at the side of the main burrow tunnels constructed by larger species. Members of G. insolitus were not found estivating at the surface, such as under fallen wood, nor was it usually found in crayfish burrows unoccupied by the host crayfish. This study indicates that members of G. insolitus are commensal upon larger crayfish species, using their burrows to survive the seasonal drying of their habitat. Conservation strategies for populations of G. insolitus will need to consider co-existing species of burrowing crayfish.     

Phylogenetic and morphological assessment of five new species of Thozetella from an Australian rainforest

During an investigation of saprobic microfungi in leaf litter from an Australian rainforest, five new species of Thozetella, namely T. acerosa, T. boonjiensis, T. falcata, T. gigantea and T. queenslandica, were identified and these are described and illustrated here. The morphology of specimens derived from cultures grown under different conditions and from natural substrata was compared. DNA sequence data of ITS regions within nuclear rDNA confirmed the morphological species concept and indicated that Thozetella species are anamorphs of the ascomycete genus Chaetosphaeria.     

Selection on leaf ecophysiological traits in a desert hybrid Helianthus species and early-generation hybrids

Leaf ecophysiological traits related to carbon gain and resource use are expected to be under strong selection in desert annuals. We used comparative and phenotypic selection approaches to investigate the importance of leaf ecophysiological traits for Helianthus anomalus, a diploid annual sunflower species of hybrid origin that is endemic to active desert dunes. Comparisons were made within and among five genotypic classes: H. anomalus, its ancestral parent species (H. annuus and H. petiolaris), and two backcrossed populations of the parental species (designated BC2ann and BC2pet) representing putative ancestors of H. anomalus. Seedlings were transplanted into H. anomalus habitat at Little Sahara Dunes, Utah, and followed through a summer growing season for leaf ecophysiological traits, phenology, and fitness estimated as vegetative biomass. Helianthus anomalus had a unique combination of traits when compared to its ancestral parent species, suggesting that lower leaf nitrogen and greater leaf succulence might be adaptive. However, selection on leaf traits in H. anomalus favored larger leaf area and greater nitrogen, which was not consistent with the extreme traits of H. anomalus relative to its ancestral parents. Also contrary to expectation, current selection on the leaf traits in the backcross populations was not consistently similar to, or resulting in evolution toward, the current H. anomalus phenotype. Only the selection for greater leaf succulence in BC2ann and greater water-use efficiency in BC2pet would result in evolution toward the current H. anomalus phenotype. It was surprising that the action of phenotypic selection depended greatly on the genotypic class for these closely related sunflower hybrids grown in a common environment. We speculate that this may be due to either phenotypic correlations between measured and unmeasured but functionally related traits or due to the three genotypic classes experiencing the environment differently as a result of their differing morphology.     

Lectotypification of Achillea santolina L. and Achillea falcata L. (Compositae-Anthemideae)

The lectotypes of Achillea chillea santolina L. and A. falcata L. (Achillea sect. Achillea) have been confrmed to be in the Clifford Herbarium. A. santolina L. cannot be retained as the generitype, and the selection of A. millefolium L. instead is confirmed. The species concept of the Linnaean A. santolina did not correspond to the post-Linnaean usage of this name. In most cases, A. santolina L. had been confused with A. wilhelmii C. Koch, but morphological differences separate those two species distinctly. The only extant element of A. falcata L. is found in the Clifford Herbarium, and this specimen corresponds principally to what is considered to be A. falcata today. Deviation in leaf structures is due to this material being of cultivated origin.     

A taxonomic review of the genus Hypocalymma (Myrtaceae)

The genus Hypocalymma endemic to Western Australia and comprising 22 species species including the widely cultivated Swan River Myrtle and Swamp Myrtle, is revised. Nine new species ( H. connatum, H. hirsutum, H, gardneri, H. jessicae, H. melaleucoides, H. serrulatum, H. sylvestris, H. tenuatum and H. uncinatum ), two new subspecies ( H. cordifolium subsp. minus and H. strictum subsp. elongatum ) and one new combination ( H. angustifolium subsp. longifolium ) are described or made. A key to all species is presented for this horticulturally significant genus.     

Associations of leaf miners and leaf gallers with island plants of different residency histories

Aim Introduced plant species are less likely to be attacked by herbivores than are native plant species. Isolated oceanic islands provide an excellent model system for comparing the associations between herbivore species and plant species of different residency histories, namely endemic, indigenous (non‐endemic) or introduced (naturalized or cultivated) species. My aim was to test the prediction that, on isolated oceanic islands, introduced plant species have a lower tendency to have an association with insect herbivores than do endemic and indigenous plant species. Location Ogasawara (Bonin) Islands in the western Pacific Ocean. Methods I examined the presence/absence of leaf‐mining and leaf‐galling insect species on 71 endemic, 31 indigenous, 18 naturalized and 31 cultivated (introduced but not naturalized) species of woody plants from 2004 to 2008. Results Leaf‐mining insect species were found on 53.5%, 35.5%, 11.1% and 16.1% and leaf‐galling species were found on 14.1%, 9.7%, 5.6% and 0% of endemic, indigenous, naturalized and cultivated plant species, respectively. Species of Lepidoptera (moths) and Hemiptera (primarily psyllids) comprised the dominant types of leaf miners and leaf gallers, respectively. Main conclusions The incidence of leaf miners and leaf gallers differed as a function of residency history of the plant species. Introduced (naturalized and cultivated) species were less frequently associated with leaf miners and leaf gallers than were native (endemic and indigenous) species, indicating that the leaf‐mining and leaf‐galling insect species, most of which feed on leaves of a particular native plant genus (i.e. they show oligophagy), have not yet begun to utilize most introduced plant species.     

Do rock endemic and widespread plant species differ under the Leaf–Height–Seed plant ecology strategy scheme?

Westoby (1998) proposed the Leaf–Height–Seed (L–H–S) scheme, i.e. the use of three functional traits, specific leaf area (SLA), plant canopy height and seed mass, to describe plant ecological strategies. In this study, we examine whether endemic species from cliffs and rocky outcrops can be discriminated in a regional Mediterranean flora according to these three traits. First, we conducted a comparison across 13 pairs of rock endemic species and widespread congeners. Second, we performed a canonical discriminant analysis to compare the position in the L–H–S volume of these 13 pairs of endemic and widespread congeners with that of 35 phylogenetically unrelated widespread species taken from the same regional flora. Our results show that rock endemic species only differ from their widespread congeners in their smaller stature. However, when compared with the 35 unrelated widespread species, endemic species are discriminated by higher SLA and taller stature, and thus are not close to the stress‐tolerant pole of ecological strategies (small stature, low SLA), as hypothesized in the literature.     

黄花苜蓿与蒺藜苜蓿对土壤低磷胁迫适应策略的比较研究

土壤有效磷(P)含量低是限制植物生长的主要因素之一。根形态变化和根系大量分泌以柠檬酸为主的有机酸是植物适应土壤P素缺乏的重要机制。以广泛分布于我国北方的重要豆科牧草黄花苜蓿(Medicago falcata)和豆科模式植物蒺藜苜蓿(M. truncatula)为材料, 采用砂培方法, 研究了低P胁迫对其植株生长、根系形态和柠檬酸分泌的影响, 对比了两种苜蓿适应低P胁迫的不同策略。结果表明: 1)低P处理显著抑制了蒺藜苜蓿与黄花苜蓿的地上部生长, 而对地下部生长影响较小, 从而导致根冠比增加。2)低P胁迫显著降低黄花苜蓿的总根长和侧根长, 而对蒺藜苜蓿的上述根系形态指标没有显著影响。3)低P胁迫促进两种苜蓿根系的柠檬酸分泌, 无论是在正常供P还是低P胁迫条件下, 黄花苜蓿根系分泌柠檬酸量显著高于蒺藜苜蓿根系。上述结果表明, 黄花苜蓿和蒺藜苜蓿对低P胁迫的适应策略不同, 低P胁迫下, 黄花苜蓿主要通过根系大量分泌柠檬酸, 活化根际难溶态P来提高对P的吸收, 而蒺藜苜蓿维持较大的根系是其适应低P胁迫的主要策略。     

Variability of phytoplasma associated with few ornamental crop species in Uttar Pradesh,India

Abstract

The economic importance of ornamentals has been advancing significantly in many countries due to continuous international demand. Like other crops, ornamental plants are also affected by a number of pathogens and the phytoplasmas diseases are equally important group of pathogens which is responsible for damaging the different ornamental plant species and thereby affecting their market value. In the present investigation, total 24 symptomatic leaf samples of 8 ornamental plant species (C. roseus, R. rubiginosa, C. variegatum, Z. elegans, J. gendurusa, T. erecta, H. rosa sinensis, J. sambrac) were analyzed which were found positive in nested PCR assays with R16F2n/R16R2 primers. The phytoplasma associated with ornamental plant species collected from different districts of UP in the present investigation are belongs to 16Sr I, II, VI and XIV group.     

鹤山重建植被的几种优势种叶解剖学研究

对南亚热带鹤山恢复植被5种优势种湿地松（Pinus elliottii）,马占相思（Acacia mangium）,大叶相思（Acacia auriculaeformis）,九节（Psychotria rubra）和南洋楹（Albizia falcata）进行了叶解剖学研究。结果显示,变化表现在表皮角质膜的厚度、细胞壁的厚度和形状,叶肉组织中海绵组织和栅栏组织的分化,内皮层维管束的构造等。为以后进一步探讨植被恢复过程中叶解剖结构的变化提供了实验基础。     

An analysis of seasonal dynamics of a mixed population of Daphnia, and the associated cladoceran community

SUMMARY. The dynamics of a mixed population of Daphnia (D. ambigua and D. parvula) are analysed over 9 months in a small eutrophic lake. A spring peak of D. ambigua occurred shortly after ice break-up. Decline of D. ambigua coincided with a high occurrence of sexual reproduction, the appearance of D. parvula which did not become abundant, and a substantial increase in Ceriodaphnia quadrangula . A third cladoceran, Bosmina longirostris , was abundant before and after the period of numerical dominance by D. ambigua , but declined to very low numbers coincident with the increase in D. ambigua.
Estimates of egg hatching rate at various temperatures demonstrate that these three cladocerans have different rate responses to temperature, and that seasonal succession of species is predictable from temperature alone. The importance of temperature versus species interactions in controlling species succession is discussed.     

The Chromosome Numbers of 12 Species in Orchidaceae from China

The present paper reports the chromosome numbers of 12 species in Orchidaceae from China. The results are as follows: Bletilla striata (Thunb.) Rchb. f. 2n= 32, Calanthe discolor Lindl. 2n=40, Calanthe hamata Hand. -Mazz. 2n=40, Cephalanthera erecta (Thunb.) Bl. 2n=34, Cephalanthera falcata (Thunb.) B1. 2n=34, Changnienia amoena Chien 2n=46, Cremastra appendiculata (D. Don) Makino 2n = 42, Dendrobium moniliforme (L.) Sw. 2n=38, Gastrodia elata Bl. n=15, 18, Liparis dunnii Rolfe 2n= 20, Platanthera minor (Miq.) Rchb. f. 2n=42, Pleione bulbocoidioides (Franch.) Rolfe 2n=40.     

西双版纳地区不同植被亚型蚁科昆虫群落研究

研究了西双版纳地区１６各被亚型蚂蚁的特有种、优势种、物种多样性指数、均匀度指数、优势度指数和相似性系数。所采蚂蚁分隶于８亚科６６属２２０种。雨季的季节性十麻蚂蚁物种多样性指数最大,为２．９０８;旱季的茶园中多样性指数最小,为０．１１４。以山地雨林和季风常绿阔叶林蚂蚁物各组成相似性系数最大,为０．３５６;以温暖性叶阔叶林和茶园相似性系数最小,为０．０１７。１６种植被亚型均有特有种,其中半常绿季雨林特     

Patterns of intra- and interspecific association in leaf-mining insects on three oak host species

Abstract. 1. We determined mortality and distributional patterns of leaf miners on three oak host species (Quercus falcata, Q.nigra and Q.hemisphaerica) in northern Florida, U.S.A.
2. Patterns of intra- and interspecific occurrence within leaves, and mortality of five most abundant leaf miner species were analysed as a test of competition.
3. Miners co-occurred on leaves more often that expected by chance (P<0.05) in six of ten possible species combinations and log-linear model analysis showed no negative higher-order interactions.
4. All five miner species had highly clumped distributions between leaves (P<0.01).
5. Leaf miner survival was less than expected for four of five species when co-occurring on leaves with conspecifics than when mining with heterospecifics or alone (P<0.05).
6. We conclude that interspecific competition is unapparent within this leaf miner guild and that intraspecific competition occurs in four of the five major leaf miner species. We discuss leaf miner selection of common leaves, perhaps based on chemical/physical leaf characters, as a cause of intra- and interspecific aggregation.     

Studies on the rust,Maravalia cryptostegiae,a potential biological control agent of rubber-vine weed,Cryptostegia grandiflora (Asclepiadaceae: Periplocoideae), in Australia,III: Host range

Seventy-one plant species, which were selected using a centrifugal phylogenetic method, were screened againstMaravalia cryptostegiae, an endemic rust of rubber-vine (Cryptostegia grandiflora) in Madagascar. All species and variants of the genusCryptostegia proved to be highly susceptible to the rust under optimum greenhouse conditions. Two other species belonging to the same subfamily Periplocoideae,Gonocrypta grevei from Madagascar andCryptolepis grayi from Australia, developed fertile sori but could still be classified as partially resistant, based on the results of a leaf clearing and staining technique. Fifteen assessment categories and 10 susceptibility ratings were designated by analysing both macro- and microsymptoms. Five resistance mechanisms were identified in the non-hosts and these are described and illustrated. Resistance reactions ranged from complete suppression of spore germination on the plant cuticle to restriction of sorus development due to the collapse of rust haustoria. The significance of host range studies are discussed in relation to the use of rust fungi as classical biological control agents of weeds, and specifically the release ofM. cryptostegiae in Australia.