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1.
Shortleaf pine (n = 93) and loblolly pine (n = 112) trees representing 22 seed sources or 16 physiographic populations were sampled from Southwide Southern Pine Seed Source Study plantings located in Oklahoma, Arkansas, and Mississippi. The sampled trees were grown from shortleaf pine and loblolly pine seeds formed in 1951 and 1952, prior to the start of intensive forest management across their native ranges. Amplification fragment length polymorphism (AFLP) markers were developed and used to study genetic diversity and its structure in these pine species. After screening 48 primer pairs, 17 and 21 pairs were selected that produced 794 and 647 AFLPs in shortleaf pine and loblolly pine, respectively. High-AFLP-based genetic diversity exists within shortleaf pine and loblolly pine, and most (84.73% in shortleaf pine; 87.69% in loblolly pine) of this diversity is maintained within physiographic populations. The high value of unbiased measures of genetic identity and low value of genetic distance for all pairwise comparisons indicates that the populations have similar genetic structures. For shortleaf pine, there was no significant correlation between geographic distance and genetic distance (r = 0.28), while for loblolly pine there was a weak but significant correlation (r = 0.51).  相似文献   

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分子系统学研究将传统梧桐科与锦葵科、木棉科和椴树科合并为广义锦葵科,并进一步分为9个亚科.然而,9个亚科之间的关系尚未完全明确,且梧桐亚科内的属间关系也未得到解决.为了明确梧桐亚科在锦葵科中的系统发育位置,厘清梧桐亚科内部属间系统发育关系,该研究对锦葵科8个亚科进行取样,共选取55个样本,基于叶绿体基因组数据,采用最大...  相似文献   

4.
Miconia punctibullata, a new species of Melastomataceae from Colombia, is described and illustrated. The new species can be distinguished by its scandent herbaceous habit, stems and inflorescences with swollen annular projections below the nodes, punctations with sessile, glandular trichomes on the abaxial surface of the leaf, compound dichasial inflorescences, and bright yellow petals. A key to all species of Miconia with annular stem projections is provided.
Resumen  Se describe e ilustra Miconia punctibullata, una nueva especie colombiana de Melastomataceae, caracterizada por el hábito herbáceo semiescandente, la presencia de proyecciones anulares engrosadas por debajo de los nudos (manicaduras) en tallos y ejes de la inflorescencia, punteaduras con tricomas glandulares sésiles por el envés de la lámina foliar, inflorescencias en dicasio compuesto, y pétalos amarillos. Se incluye una clave para todas las especies de Miconia con nudos manicados.
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5.
Abstract

A two-year study has been conducted in an abandoned Pb/Zn mining site, with the aim of investigating the feasibility of phytoremediation using two native Mediterranean plants (Pistacia lentiscus and Scrophularia bicolor) and of assessing the performance of amendments able to reduce the toxic effects of heavy metals. The amendments used were compost, chemical fertilizer, and zeolites, used singly or in combination. Depending on the amendments applied, the two species showed different mortality rates in the different plots, but all produced an increase in P. lentiscus survival, while S. bicolor survival improved only when amended with zeolite or zeolite + fertilizer. Scrophularia bicolor proved to be a more efficient accumulator than P. lentiscus, especially for Pb uptake. Pistacia lentiscus accumulated metals mostly in the roots. The effect of amendments was to generally reduce the bioavailable metal fraction, especially lead, in the plots amended with compost. Pistacia lentiscus proved to be the most suitable species for phytostabilization and environmental restoration, both for its resistance to metals and high phytomass production. The experiments demonstrate that the use of compost not only encourages this kind of revegetation in degraded areas, but is also an economical option that uses a by-product of solid municipal waste treatment.  相似文献   

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In this tribute, I offer my best wishes to Achim Trebst on his 80th birthday on June 9, 2009. At the invitation of Govindjee, I present here a perspective of some of our joint research during 1970s through 2000s.  相似文献   

8.
African species of Oxyscelio (Hymenoptera: Platygastridae s.l.) are revised. A total of 14 species are recognized, 13 of which are described as new: Oxyscelio absentiae Burks, sp. n., Oxyscelio galeri Burks, sp. n., Oxyscelio gyri Burks, sp. n., Oxyscelio idoli Burks, sp. n., Oxyscelio intensionis Burks, sp. n., Oxyscelio io Burks, sp. n., Oxyscelio kylix Burks, sp. n., Oxyscelio lunae Burks, sp. n., Oxyscelio nemesis Burks, sp. n., Oxyscelio pulveris Burks, sp. n., Oxyscelio quassus Burks, sp. n., Oxyscelio teli Burks, sp. n. and Oxyscelio xenii Burks, sp. n. The genus Freniger Szabó, syn. n. is recognized as part of an endemic African species group of Oxyscelio with incomplete hind wing venation, and Oxyscelio bicolor (Szabó), comb. n. is therefore recognized as the only previously described species of Oxyscelio from Africa. The Oxyscelio crateris and Oxyscelio cuculli species groups, previously known from southeast Asia, are represented in Africa by seven and one species respectively.  相似文献   

9.
Recent evidence shows that the serine protease inhibitor Kazal type 3 (Spink3) has more diverse functions than expected. To gain insight into its function, we analyzed the spatiotemporal expression profile of Spink3, using in situ hybridization (ISH) and a Spink3 ( +/lacZ ) knock-in mouse, in which lacZ was inserted into the Spink3 locus. Spink3 ( lacZ ) expression was first observed in the foregut, midgut, hindgut and the forebrain/midbrain junction region at 9.5 days post coitus (dpc). In the pancreas, Spink3 mRNA was detected at 11.5 dpc, before formation of the typical shape of the exocrine structure of the pancreas. Acinar cell expression was clearly identified by 13.5 dpc. After differentiation of the intestinal tract, Spink3 ( lacZ ) expression was observed in the large intestine at 11.5 dpc, followed by expression in the small intestine at 13.5 dpc, before appearance of intestinal digestive enzymes. Spink3 mRNA and Spink3 ( lacZ ) activity were also detected in other tissues, including the mesonephric tubules and the urogenital ridge at 11.5 dpc, the genital swelling at 13.5 dpc, the ductus epididymis at 17.5 dpc, and the seminal vesicle at 8 weeks. These data suggest that Spink3 may play important roles in proliferation and/or differentiation of various cell types during development.  相似文献   

10.
Rates of net photosynthesis (P N) and transpiration (E), and leaf temperature (TL) of maintenance leaves of tea under plucking were affected by photosynthetic photon flux densities (PPFD) of 200–2 200 μmol m−2 s−1. P N gradually increased with the increase of PPFD from 200 to 1 200 μmol m−2 s−1 and thereafter sharply declined. Maximum P N was 13.95 μmol m−2 s−1 at 1 200 μmol m−2 s−1 PPFD. There was no significant variation of P N among PPFD at 1 400–1 800 μmol m−2 s−1. Significant drop of P N occurred at 2 000 μmol m−2 s−1. PPFD at 2 200 μmol m−2 s−1 reduced photosynthesis to 6.92 μmol m−2 s−1. PPFD had a strong correlation with TL and E. Both TL and E linearly increased from 200 to 2 200 μmol m−2 s−1 PPFD. TL and E were highly correlated. The optimum TL for maximum P N was 26.0 °C after which P N declined significantly. E had a positive correlation with P N.  相似文献   

11.
Two new Colombian species of Magnolia from Antioquia are described and illustrated. Magnolia coronata can be distinguished by a ring of woolly, golden pubescence present in the youngest internodes of the branches. Magnolia jardinensis has numerous punctations on the outermost petals and a woolly, yellowish pubescence. Magnolia chimantensis, a species previously known only from the type locality in Chimantá, Venezuela, is reported for the first time from Santander, Colombia.
Resumen  Se describen e ilustran dos especies colombianas de Magnolia, nuevas para la ciencia, provenientes del departamento de Antioquia. Magnolia coronata se distingue por un anillo de indumento lanoso dorado presente en el entrenudo más joven de las ramillas. Magnolia jardinensis se caracteriza por las numerosas puntuaciones presentes en los pétalos más externos y por la pubescencia lanosa y amarillenta. Se presentan los primeros registros para Colombia, en el departamento de Santander, de la especie Magnolia chimantensis, conocida hasta ahora solamente por la colección del tipo proveniente de Chimantá, en Venezuela.
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12.
Abstract

The large amount of morphological variability within Fritillaria montana Hoppe ex W.D.J. Koch, a southeastern European species described from northeastern Italy, led to the creation of several further taxa: Fritillaria caussolensis Goaty & Pons ex Adoino from southeastern France, Fritillaria orsiniana Parl. from central Italy, Fritillaria intermedia N. Terracc. and Fritillaria pollinensis N. Terracc. from southern Italy. Aiming to test the taxonomic value of these taxa, a biometric study of both herbarium and living specimens of F. montana s.l. is carried out. A total of 22 morphological features were analysed and measured in 417 plants from 46 different localities, including loci classici of all the involved taxa. In addition, typical populations of F. montana, F. caussolensis, F. intermedia, F. orsiniana and F. pollinensis and also several other Italian populations resulted with 2n = 18 chromosomes. We also counted 2n = 27 chromosomes in endotriploid cells of plants from Abruzzo. However, there is no clear‐cut correlation between morphology and karyology. The biometric analysis, together with many observations on fresh material in the field, revealed that F. montana is a single polymorphic species with no infraspecific taxa.  相似文献   

13.
In the present study, the chemical composition of the essential oils from aerial parts of Centaurea grinensis Reuter (K) collected at ?uta Lova, near Senj (Croatia), and aerial parts (L1) and flowers (L2) of C. apiculata Ledeb. collected near Rebro village, near Breznik town, Znepole Region (Bulgaria), both belonging to subgenus Lopholoma (Cass.) Dobrocz, was evaluated by GC and GC-MS. The main components of K were 4-vinyl guaiacol (21.5%), hexadecanoic acid (16.2%), acetophenone (12.5%). Caryophyllene oxide (15.8%) together with sphathulenol (14.5%) and humulene epoxide II (9.4%) were recognized as the main constituent of both the aerial part (L1) and flowers (L2) of C. apiculata. Furthermore, a complete review on the composition of the essential oils of all the Centaurea taxa belonging to subgenus Lopholoma studied so far has been inserted and cluster analysis (PCA) was carried out.  相似文献   

14.
Total extracts and kuwanon G from Morus nigra root bark showed antifungal activity against several phytopathogenic fungi, with minimal inhibitory concentration (MIC50) ranging from 32 to 128 μg/ml and from 16 to 64 μg/ml, respectively. Acetonic extracts inhibited 60% B. cinerea biofilm formation at concentration of 128 μg/ml.  相似文献   

15.
The gilthead seabream is a protandrous seasonal breeding teleost that is an excellent model for studying the testicular regression process which occurs in both seasonal testicular involution and sex reversion. Little is known about the cell types and the molecular mechanisms involved in such processes, mainly because of the lack of appropriate methods for testis dissociation, and testicular cell isolation, culture and functional characterization. We have previously reported that gilthead seabream acidophilic granulocytes infiltrate the testis at post-spawning stage, settle close to the spermatogonia and accumulate intracellular interleukin-1β. In this paper, we report several flow cytometry based assays which allow to establish the role played by gilthead seabream testicular acidophilic granulocytes and permits their quantification. Published: June 29, 2004.  相似文献   

16.
Tourette's syndrome is a lifelong disorder characterized by multiple motor and verbal tics. The present study examined relaxation training and desensitization training as a method of reducing the frequency and intensity of tics and the distress they caused in a young adult diagnosed with Tourette's syndrome. After a period of symptom monitoring the subject underwent 3 weeks of intensive training in relaxation skills and 5 weeks of desensitization training with situational cues previously identified as eliciting Tourette's symptoms. According to self-report monitoring, the experience of symptoms was decreased across 3 global dimensions: distress (48%), frequency (48%), and intensity (50%), and an hourly symptom count (50%). Collateral parental symptom report agreed with an observed decrease across distress (40%), frequency (41%), and intensity (40%). Inspection of data suggests that both components of stress management added to total treatment efficacy.  相似文献   

17.
The genus Mortoniodendron is distributed from southeastern Mexico to Colombia and contains about 18 species of trees and shrubs. The main goal of this study is to describe and compare the leaf architecture and the anatomy of 11 species of Mortoniodendron using cleared leaves and paradermal and transverse leaf sections. All of the species of Mortoniodendron share a simple lamina with an entire margin. The differences among the species include the venation pattern, the relative thickness and course of the secondary veins, the presence or absence of the intersecondary veins, the tertiary vein pattern, the number of branches in veinlets, and the marginal ultimate venation. The leaf anatomy is similar to other species of the Malvaceae s.l.: for example, mucilage cells are common in Mortoniodendron. There are unique attributes of the leaf architecture and anatomy, such as the eucamptodromous venation pattern of M. guatemalense, which facilitates the identification of the species. The species M. palaciosii, M. pentagonum, M. ruizii, M. uxpanapense, and M. sp. nov. share features that suggest that they are closely related.  相似文献   

18.
Abstract

Five populations belonging to three subspecies of Dianthus rupicola Biv. (D. rupicola subsp. rupicola, D. rupicola subsp. aeolicus, and D. rupicola subsp. lopadusanus) and growing in different geographical areas of Sicily were tested for seed germination at various temperatures. All populations showed high germination rates with an optimum temperature between 15°C and 25°C. Efficient seed germination might contribute significantly to the preservation of these subspecies which are currently exposed to several environmental threats.  相似文献   

19.
Hybrids including Hystrix patula, H. duthiei and H. longearistata were obtained and genetic relationships among them were studied. Meiotic pairing in hybrids of H. duthiei × Psathyrostachys juncea (Ns), H. longearistata × Psa. juncea (Ns), Leymus multicaulis (NsXm) × H. duthiei, L. multicaulis (NsXm) × H. longearistata, Elymus sibiricus (StH) × H. patula, Roegneria ciliaris (StY) × H. patula, R. ciliaris (StY) × H. duthiei and R. ciliaris (StY) × H. longearistata averaged 5.76, 5.44, 11.94, 10.88, 10.08, 3.57, 0.46 and 0.90 bivalents per cell, respectively. The results indicated that H. duthiei and H. longearistata had the NsXm genomes of Leymus, while H. patula contained the StH genomes and had a low genome affinity with the StY genomes of Roegneria. Results of genome-specific RAPD assay were comparable with the chromosome pairing data. According to the genomic system of classification in Triticeae, H. patula should be considered as Elymus hystrix L., while H. duthiei and H. longearistata as Leymus duthiei and Leymus duthiei ssp. longearistata, respectively.  相似文献   

20.
Giant bear-dogs of the genera Amphicyon and Ischyrocyon (Carnivora, Amphicyonidae, Amphicyoninae) were the largest carnivorans in North America during middle and late Miocene (17.5–8.8 Mya) with a dental and skeletal morphology that combined features found in living Ursidae, Canidae, and Felidae. This study tests previously proposed models of diet and hunting behaviour of these extinct carnivorans. Relative grinding area (RGA) of lower molars and wear pattern on upper molars suggest that bear-dogs were carnivorous. Amphicyon and Ischyrocyon possessed skeletal features of both ambush (short distal limb segments) and pursuit (caudally bent olecranon process of ulna) living predators. Therefore, bear-dogs probably pursued their prey (mediportal ungulates) for a longer distance but at a slower speed than do living ambush predators. Upon catching up to its prey a bear-dog probably seized it with powerfully muscled forelimbs and killed it by tearing into its ribcage or neck with canines set in a narrow rostrum.  相似文献   

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