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41.
New Potentilla synonyms of the Fragaria species names are discussed and considered to be dispensable. Further unnecessary nomenclatural changes based on the argument to recognize monophyletic but not paraphyletic taxa should be avoided to maintain nomenclatural stability for global communication about plant genetic resources. The new combination Fragaria×rosea (Mabb.) K. Hammer et Pistrick is presented for the hybrid Potentilla palustris (L.) Scop. ×Fragaria×ananassa Duchesne ex Rozier. 相似文献
42.
Jürgen Schultze-Motel Reinhard Fritsch Karl Hammer Peter Hanelt Joachim Kruse Helga I. Maas Harald Ohole Klaus Pistrick 《Genetic Resources and Crop Evolution》1987,35(2):421-439
Summary Important papers on taxonomy and evolution of cultivated plants published in 1985 and 1986 were compiled and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1985/1986
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1985 und 1986 wurden zusammengestellt und kurz kommentiert.
¶rt; : 1985–1986
¶rt; , 1985 1986 . .相似文献
43.
A survey was undertaken in two valleys of the Bumthang area in Central Bhutan to study the morphological diversity, farmers’
knowledge, management practices, yield and income generation potential of the neglected Himalayan Pear (Pyrus pashia Hamilton ex D. Don). For this study a total of 148 Pyrus pashia accessions were collected and 103 households interviewed. Three quantitative and 14 qualitative traits such as colour, size,
shape and texture of fruits and tree habit were used for morphological characterization of the accessions. The results demonstrated
a high morphological diversity within the P. pashia trees. Fruit shape varied widely from globose to pyriform, fruit skin colour from light yellow and glossy to brown and dull.
The observed diversity is likely due to the fact that under farmers’ conditions trees are propagated through seedlings rather
than by grafting. None of the characters were specific and correlated with region or altitude. Distinct local cultivars with
specific characters were absent making it impossible to group the pears morphologically. Interviews revealed low numbers of
trees per farmers, lacking marketability of the fruits and farmers’ subsequent preference for improved varieties as major
obstacles for the in situ preservation of biodiversity in P. pashia in this area. 相似文献
44.
45.
Shallow soil A horizon (topsoil) caused by soil erosion and soil movement from cultivation is known to reduce soil and crop productivity. The reduction may be related to limitation of root growth. A field study was conducted to investigate the effects of topsoil thickness on distributions of root density and growth. Soybeans [Glycine max (L.) Merr.] were grown on plots of Mexico silt loam (fine, montmorillonitic, mesic Mollic Endoaqualfs) with topsoil thicknesses of 0, 12.5, 25.0, and 37.5 cm above the Bt horizons. Root density was measured 60 and 90 days after planting using a minirhizotron video‐camera system. Root density was significantly reduced as topsoil thickness decreased from 37.5 to 0 cm. Mean density and net change of the density across profile between 30 and 60 days of growth had a linear function of topsoil thickness. The reduction and lower activity induced by shallow topsoil were attributed to detrimental properties in the Bt horizons. Root distribution pattern and rooting depth were not significantly affected by topsoil thickness. The roots appeared to be accumulated on the upper layers of the Bt horizons. Roots growing in thicker topsoil were more active than roots growing without topsoil. High soil moisture content during the growing season may mitigate the detrimental effects of shallow topsoil, inhibit root penetration, and enhance root activity. 相似文献
46.
Jürgen Schultze-Motel Reinhard Fritsch Karl Hammer Peter Hanelt Joachim Kruse Harald Ohle Klaus Pistrick 《Genetic Resources and Crop Evolution》1985,33(2):307-324
Summary Important papers on taxonomy and evolution of cultivated plants published in 1983 and 1984 were complied and briefly discussed.
Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1983/1984
Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1983 und 1984 wurden zusammengestellt und kurz kommentiert.
: 1983–1984
, 1983 1984 . .相似文献
47.
Summary In continuation of collecting missions in the last four years a further mission has been carried out in South Italy jointly by staff members of the Istituto del Germoplasma, Bari, and the Zentralinstitut für Genetik und Kulturpflanzenforschung, Gatersleben, in September 1984 for studying and collecting indigenous forms of cultivated plants and their wild relatives. 185 samples, mainly of cereals, vegetables and grain legumes have been collected. The material represents highly variable old land-races; this is especially true for wheat, oats, maize,Brassica spp., french beans and faba beans. In Sicily wildBrassica spp. have been collected and in some places introgression from wild into cultivatedBrassica races could be observed. The results of this mission increase our knowledge concerning the flora of cultivated plants of South Italy considerably and stress the necessity for continuing the exploration of plant genetic resources in this region.
Sammlung von Kulturpflanzen-Landsorten in Süditalien 1984
Zusammenfassung In Fortführung von Sammelreisen der letzten vier Jahre wurde eine weitere Reise in Süditalien gemeinsam von Mitarbeitern des Istituto del Germoplasma, Bari, und des Zentralinstituts für Genetik und Kulturpflanzenforschung, Gatersleben, im September 1984 unternommen, die dem Studium und der Sammlung indigener Formen von Kulturpflanzen und ihrer verwandten Wildsippen diente. 185 Proben, vor allem von Getreiden, Gemüsen und Körnerleguminosen, wurden gesammelt. Das Material besteht aus hochvariablen alten Landsorten, besonders von Weizen, Hafer, Mais, Kohlsippen, Gartenbohnen und Ackerbohnen. In Sizilien wurden Wildkohle gesammelt, und an einigen Stellen konnten Introgressionen von Wildin Kultursippen beobachtet werden. Die Ergebnisse dieser Sammelreise, die unsere Kenntnisse der Kulturpflanzenflora Süditaliens beträchtlich erweitern, unterstreichen die Notwendigkeit zur Fortführung der Exploration pflanzengenetischer Ressourcen dieses Gebietes.
1984
. 1984 . . 185 , , , ; ; , , , , , . , . , , .相似文献
48.
49.
50.
Miguel Esquivel Leonor Castiñeiras Bartolomé Rodríguez Karl Hammer 《Genetic Resources and Crop Evolution》1987,35(2):367-378
Summary After a short introduction into recent collecting activities in Cuba information is provided concerning the joint expedition of the Instituto de Investigaciones Fundamentales en Agricultura Tropical and the Zentralinstitut für Genetik und Kulturpflanzenforschung in the province of Holguín, Eastern Cuba, in February 1986 within the agreement between the Academy of Sciences of Cuba and the Academy of Sciences of the German Democratic Republic. Altogether 249 accessions of vegetables, pulses, cereals and other crops were collected. A remarkable diversity was found inCapsicum andPhaseolus. The material collected is important for breeding purposes.
Sammlung pflanzlicher genetischer Ressourcen in Kuba
Zusammenfassung Nach einer kurzen Einführung in die Sammelarbeit der letzten Jahre in Kuba folgen Informationen über die gemeinsame Expedition des Instituto de Investigaciones Fundamentales en Agricultura Tropical und des Zentralinstituts für Genetik und Kulturpflanzenforschung, die im Rahmen des Abkommens zwischen der Akademie der Wissenschaften Kubas und der Akademie der Wissenschaften der Deutschen Demokratischen Republik im Februar 1986 durchgeführt wurde und in die Provinz Holguín, Ost-Kuba, führte. Insegsamt wurden 249 Proben von Gemüsen, Hülsenfrüchten, Getreiden und anderen Fruchtarten gesammelt. Eine bemerkenswerte Variation wurde beiCapsicum andPhaseolus gefunden. Das Sammelmaterial ist für Züchtungszwecke von Bedeutung.
¶rt; , , , ¶rt; . C 1986 . . 249 , , . Capsicum Phaseolus. .相似文献