摘要 :
El epíteto específico tuberosas fue utilizado por primera por Salzmann en el listado de unos exsiccata (cf. Flora 10(2): 95, 1827), pero no iba acompanado de descripción alguna y resultó, por tanto, ser un nom. nucí. Posterio...
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El epíteto específico tuberosas fue utilizado por primera por Salzmann en el listado de unos exsiccata (cf. Flora 10(2): 95, 1827), pero no iba acompanado de descripción alguna y resultó, por tanto, ser un nom. nucí. Posteriormente, ha sido validado por Trinius en el rango varietal [Holcus lanatus var. tuberosus Salzm. ex Trin. in Mem. Acad. Imp. Sci. Saint-Pétersbourg, Ser. 6, Sci. Math., Second Pt. Sci. Nat. 5(2): 86 (1840)] al describirlo con la siguiente frase: "fe, Radice tuberosa, panícula 1-1 1/2 - pollicari: Holcus tuberosus Salzm! p.86". Pero la publicación de Trinius parece no haber sido muy conocida, ya que otros autores como Ball (J. Linn. Soc., Bot. 16: 708 (1878), Steud., Syn. Pl. Glumac. 1: 14, 1855) o Maire (Fl. Afrique N. 2: 226, 1953), lo utilizan sin mencionar a Trinius. Todos ellos, en cualquier caso, se basan siempre en los exsiccata de Salzmann, por lo que podrían ser consierados como homotípicos.
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Anthoxanthum alpinum Lceve & Lceve has been described as a diploid perennial distributed in northern Eurasia and the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid Anthoxanthum odoratum L. have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to use different approaches to assess the relationships between close congeners, such as the pair A. odoratum/A. alpinum. Macromorphological, micromorphological, and molecular data were gathered and analysed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Different cluster analyses were performed to study the relatedness between individuals and populations. Subsequently, a principal components analysis was computed on the basis of macromorphological quantitative traits, and principal coordinates analysis was used to analyse qualitative, micromorphological, and random amplification of polymorphic DNA (RAPD) data. An analysis of molecular variance was applied to the molecular data, and the genetic differentiation between samples was measured using the FST estimator. The results showed that the geographical origin was more important than the ploidy level in explaining the relatedness between specimens and populations. Moreover, a strong correlation was found between the micromorphological traits and environmental parameters. The results of the analyses do not support the assignment of a specific taxonomic rank to A. alpinum....
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Anthoxanthum alpinum Lceve & Lceve has been described as a diploid perennial distributed in northern Eurasia and the high mountains of central and eastern Europe. Difficulties in finding reliable morphological differences between this taxon and the widespread tetraploid Anthoxanthum odoratum L. have resulted in taxonomists treating them as conspecific, despite the cytological differentiation. The purpose of this study was to use different approaches to assess the relationships between close congeners, such as the pair A. odoratum/A. alpinum. Macromorphological, micromorphological, and molecular data were gathered and analysed for 14 populations representing both taxa from Scandinavia and the Iberian Peninsula. Different cluster analyses were performed to study the relatedness between individuals and populations. Subsequently, a principal components analysis was computed on the basis of macromorphological quantitative traits, and principal coordinates analysis was used to analyse qualitative, micromorphological, and random amplification of polymorphic DNA (RAPD) data. An analysis of molecular variance was applied to the molecular data, and the genetic differentiation between samples was measured using the FST estimator. The results showed that the geographical origin was more important than the ploidy level in explaining the relatedness between specimens and populations. Moreover, a strong correlation was found between the micromorphological traits and environmental parameters. The results of the analyses do not support the assignment of a specific taxonomic rank to A. alpinum.
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This study provides evidence for frequent and multiple invasions of New Zealand's native grasses by exotic cereal and pasture viruses. Fifteen native and three exotic grasses from 29 North Island and six South Island sites were su...
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This study provides evidence for frequent and multiple invasions of New Zealand's native grasses by exotic cereal and pasture viruses. Fifteen native and three exotic grasses from 29 North Island and six South Island sites were surveyed for the presence of viruses using enzyme-linked immunosorbent assay (ELISA). Barley yellow dwarf virus and Cereal yellow dwarf virus (BYDV, CYDV: Luteoviridae) and Cocksfoot mottle virus (CoMV, Sobemovirus) are widespread throughout New Zealand. CoMV, previously considered to have a natural host range restricted to Dactylis and Triticum, was detected in Poa anceps, P. cita, Festuca novae-zelandiae, and Chionochloa rubra. New virus host reports include BYDV-PAV in Microlaena stipoides and Dichelachne crinita; BYDV-MAV in P. cita, F. novae-zelandiae and Hierochloe redolens; and CYDV-RPV in P. cita and M. stipoides. Nominal logistic regression analyses showed a correlation between the presence of exotic grass species and virus incidence. Host range experiments for BYDV-PAV and CoMV were performed with selected native and exotic grasses, and the results are discussed in context of the field-survey findings.
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This study provides evidence for frequent and multiple invasions of New Zealand's native grasses by exotic cereal and pasture viruses. Fifteen native and three exotic grasses from 29 North Island and six South Island sites were su...
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This study provides evidence for frequent and multiple invasions of New Zealand's native grasses by exotic cereal and pasture viruses. Fifteen native and three exotic grasses from 29 North Island and six South Island sites were surveyed for the presence of viruses using enzyme-linked immunosorbent assay (ELISA). Barley yellow dwarf virus and Cereal yellow dwarf virus (BYDV, CYDV: Luteoviridae) and Cocksfoot mottle virus (CoMV, Sobemovirus) are widespread throughout New Zealand. CoMV, previously considered to have a natural host range restricted to Dactylis and Triticum, was detected in Poa anceps, P. cita, Festuca novae-zelandiae, and Chionochloa rubra. New virus host reports include BYDV-PAV in Microlaena stipoides and Dichelachne crinita; BYDV-MAV in P. cita, F. novae-zelandiae and Hierochloe redolens; and CYDV-RPV in P. cita and M. stipoides. Nominal logistic regression analyses showed a correlation between the presence of exotic grass species and virus incidence. Host range experiments for BYDV-PAV and CoMV were performed with selected native and exotic grasses, and the results are discussed in context of the field-survey findings.
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Pollen grains of 57 species (representing 42 genera) of the Chloridoideae have been investigated using light, scanning and transmission electron microscopy. Two aperture patterns and nine exine patterns are distinguished using SEM...
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Pollen grains of 57 species (representing 42 genera) of the Chloridoideae have been investigated using light, scanning and transmission electron microscopy. Two aperture patterns and nine exine patterns are distinguished using SEM and TEM. These are categorized into five pollen types. Two pollen types are previously not recorded in Gramineae. A key for the identification of these pollen types is presented. Generally, pollen characters have limited systematic value in recognizing taxa at generic level or above in the Chloridoideae. An evolutionary trend is proposed that awaits verification by further systematic study. Pollen characters can be used as indicators for the areas of origin and distribution of the Chloridoideae.
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Based on multivariate analyses, a new dioecious species of Poa from the Punecla and Altoandina phytogeographical provinces of Argentina is described. This species is most similar to Poa calchaquiensis of Poa section Dioicopoa. The...
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Based on multivariate analyses, a new dioecious species of Poa from the Punecla and Altoandina phytogeographical provinces of Argentina is described. This species is most similar to Poa calchaquiensis of Poa section Dioicopoa. The ligule length, plant size, and glabrous pistillate anthoecia distinguish Poa nubensis. A key for identification and illustrations are also included.
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Inflorescence structures of 81 species and two subspecies (representing 61 genera) of the Chloridoideae have been investigated using stereo microscopy (SM). Inflorescences of the Chloridoideae are true polytelic inflorescences. Th...
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Inflorescence structures of 81 species and two subspecies (representing 61 genera) of the Chloridoideae have been investigated using stereo microscopy (SM). Inflorescences of the Chloridoideae are true polytelic inflorescences. Thirteen inflorescence subtypes are distinguished based on modes of the truncation and the homogenization. These are categorized into four basic inflorescence types. A key for the identification of these inflorescence types is presented. Generally, inflorescence characters have definite systematic value in recognizing supra-generic taxa in the Chloridoideae. Twelve processes have been identified as responsible for inflorescence diversification that awaits verification by further systematic study.
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An evolutionary pathway leading to acrotonous, 2-flowered spikelets of Panicoideae has been suggested elsewhere, which involves apical reduction of many-flowered mesotonic spikelets. Current phylogenies of the grass family show a ...
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An evolutionary pathway leading to acrotonous, 2-flowered spikelets of Panicoideae has been suggested elsewhere, which involves apical reduction of many-flowered mesotonic spikelets. Current phylogenies of the grass family show a sister relationship between Panicoideae and Centothecoideae. A survey of spikelet structures occurring among centothecoid grasses shows that some representatives of this group have intermediate morphologies which are consistent with that hypothesis. Chasmanthium and Bromuniola have many-flowered spikelets with a barren proximal floret, whereas Thysanolaena, Gouldochloa and Gynerium represent a series of apical reductions leading to 2-flowered spikelets. Moreover, many-flowered spikelets with 1-3 proximal male flowers followed by several female-fertile ones occur in Puelioideae, one of the early-diverging clades of the Poaceae. This fact suggests that some "panicoid" characters may have evolved long before the radiation of the Panicoideae took place.
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Среди Роеае и Aveneae, для которых характерны кариотипы с основным хромосомным числом х = 7, имеются роды, у которых х снижено до 6, 5...
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Среди Роеае и Aveneae, для которых характерны кариотипы с основным хромосомным числом х = 7, имеются роды, у которых х снижено до 6, 5. 4, и даже 2. В частности, необычно низкое число хромосом (2п = 4, х =2) обнаружено у Zingeria biebersteiniana (Aveneae) и Colpodium versicolor (Роеае). Для того чтобы исследовать происхождение необычного двухромосомного генома Colpodium и Zingeria, были секвенированы внутренние транскрибируемые спейсеры ITS1 и ITS2 и гены S.SSpPHK Colpodumversicolor и некоторых других представителей Aveneae и Роеае. Сравнительный анализ последовательностей ITS1 и ITS2 выявил низкое генетическое расстояние (p-distance) между последовательностями рДНК Colpodium versicolor и Zingeria biebersteiniana и обнаружил статистически высоко вероятную монофилию этих родов. Это позволяет предположить, что редукция числа хромосом до 2п = 4 имела место у общего предка Zingeria и Colpodium.
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Bamboos are generally tall, erect and woody arborescent grasses. They are mainly distributed in the tropical and subtropical regions of the world. Bamboo grows three times faster than most other plants species. Bambusa tulda belon...
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Bamboos are generally tall, erect and woody arborescent grasses. They are mainly distributed in the tropical and subtropical regions of the world. Bamboo grows three times faster than most other plants species. Bambusa tulda belongs to Poaceae familyand the subfamily Bambusoideae. Bambusa tulda also known as Indian timber bamboo is an evergreen in nature. Its shoots contain high nutritional contentsand polyphenols which show medicinal properties to cure cardiovascular diseases and some types of cancer High demand for edible bamboo shoots of Bambusa tulda in many Asian ethnic groups has led to the need for developing intensive bamboo farming. The present studies based on survey done at New Forest, Forest Research Institute (FRI), Dehradun (Uttarakhand) India, the minimum leaf size (LxB) of Bambusa tulda is 19 x 2and maximum leaf size 21 x 2,Clum height of B, tuldais (LxB)~ 15–20 and height of clum sheath(LxB) is 30 x 30.
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