Evaluation for resistance to Pyrenophora tritici-repentis in Aegilops tauschii Coss. and synthetic hexaploid wheat amphiploids

Summary A total of 59 diploid Aegilops tauschii Coss. (syn. Aegilops sguarrosa auct. non L.) and 39 synthetic hexaploid wheat accessions were evaluated for reaction to Pyrenophora tritici-repentis (Died.) Drechs. in a controlled environment, and classified using a disease rating system based on lesion type. 27 Ae. tauschii and 20 synthetic wheats were found to be resistant to tan spot disease. The overall mean disease ratings of Ae. tauschii and the synthetic wheat lines scored on a scale of 1 (resistant) to 5 (susceptible) were 1.80 and 2.38, respectively. Synthetic wheats generally showed a decrease in resistance, although several lines of synthetic wheat expressed a higher resistance than the diploid parents. Five synthetic wheat lines exhibited higher resistance than the standard resistant common wheat cultivar Red Chief.     

Chromosomal interchanges and phylogeny of some accessions of Triticum aestivum subsp. spelta

Summary The occurrence of chromosomal interchanges was studied in F1 hyrids in two diallel schemes, including nine accessions of Triticum aestivum subsp. spelta, originating from Iran, Europe and North Africa, and the common wheat variety Chinese Spring as a reference. Seven accessions of subsp. spelta differed in one translocation from Chinese Spring. The European accession Grey differed in one or perhaps two interchanges from the reference variety, and Iran 417a showed a difference of three interchanges with Chinese Spring. In total six or perhaps seven interchanges were observed. Thus the number of translocation events in subsp. spelta appeared to be low. One translocation was unique and occurred only in the accession from North Africa. Also one accession from Europe, the landrace Schwarzwald, possibly carried a unique translocation. In both diallels an interchange with a relatively low coefficient of multivalent realisation at first meiotic metaphase was observed in most accessions. The two extra translocations in Iran 417a are considered to be the result of more recent translocation events, whereas the possible second translocation in accession Grey showed such a low coefficient of multivalent realisation that its existence could be doubted.     

Prüfung vonAegilops-Arten auf Resistenz gegenPseudocercosporella herpotrichoides (Fron) Deighton

Zusammenfassung 490 Sippen von 21Aegilops-Arten wurden in den Jahren 1980 bis 1982 unter Freilandbedingungen mit künstlicher Infektion auf Resistenz gegenüber dem Erreger der Halmbruchkrankheit des Getreides,Pseudocercosporella herpotrichoides (Fron) Deighton geprüft. Außerdem erfolgte an ausgewählten Sippen die Prüfung der Jungpflanzenanfälligkeit im Phytotron. Unter denAegilops-Mustern erwiesen sich im Freiland 31 Herkünfte als resistent bzw. schwach anfällig. Im einzelnen handelte es sich um Vertreter der ArtenAe. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa undAe. tauschii. Die im Jungpflanzenstadium geprüften 7 Sippen, 3 vonAe. ventricosa und je 1 vonAe. bicornis, Ae. kotschyi undAe. lorentii, waren ebenfalls resistent bzw. schwach anfällig.

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TestingAegilops species for their reaction toPseudocercosporella herpotrichoides (Fron) Deighton

Summary From 1980–1982 490 accessions out of 21Aegilops species were tested in a field trial with artificial infection regarding their resistance toPseudocercosporella herpotrichoides (Fron) Deighton in cereal crops. Simultaneously, selected accessions were checked for their susceptibility in the seedling stage under controlled conditions in the phytotrone. Among theAegilops samples 31 accessions proved to be resistant or only slightly susceptible. This refers toAe. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa andAe. tauschii. The accessions checked in the seedling stage, i. e. 3 ofAe. ventricosa and 1 ofAe. bicornis, Ae. kotschyi andAe. lorentii, showed also resistance or only low susceptibility.

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Aegilops Pseudocercosporella herpotrichoides

1980–1982 . 490 21 Aegilops Pseudocercosporella herpotrichoides (Fron) Deighton. , . Aegilops 31 ; ¶rt; Ae. ventricosa, Ae. triuncialis, Ae. kotschyi, Ae. bicornis, Ae. columnaris, Ae. lorentii, Ae. peregrina, Ae. geniculata, Ae. speltoides, Ae. crassa, Ae. tauschii. , , Ae. ventricosa Ae. bicornis, Ae. kotschyi, Ae. lorentii .

     

Genetic studies on the powdery mildew resistance of winter barley lines derived from Hordeum spontaneum accessions collected in Israel

The genetics of the powdery mildew resistance of 15 Hordeum spontaneum-derived winter barley lines were studied in testcrosses with selected cultivars carrying the MIa12 and MIa13 resistance alleles, in order to identify the inheritance of the resistance and to test for linkage with the MIa locus on chromosome 1H (5). A total of 27 genes were identified. Only one of these genes (in line 1–12 x Dura) could eventually be allelic to a gene previously identified in H. spontaneum Koch. A monofactorial dominant inheritance was identified in the majority of the lines. Three of the tested lines possessed recessively inherited genes and in one line a dominant and a recessive gene were identified. In respect to the reaction of the lines against European mildew cultures, lines with a bifactorially inherited resistance had a broader resistance spectrum than those with a monofactorial inheritance, while lines carrying recessive factors showed a moderately expressed resistance. In three cases a linkage with the MIa locus was found, while in two further lines a possible allelism to this locus was indicated by the absence of recombinant progeny plants. By using more than two isolates for linkage analysis, it was possible to identify additional genes for mildew resistance, reaching a maximum number of four genes in the same line. In some cases, a different inheritance was observed for the resistance of the same line against different isolates. It was assumed that different genes exist, each being effective against a different isolate.     

Differential staining of mitotic chromosomes from inbred lines and hybrids ofZea mays L.

Summary The Giemsa banding patterns of four inbred lines (DB1113, DB1116, WIR44 and WIR27) ofZea mays and their hybrids have been compared. The polymorphism of knob heterochromatin of 4 chromosome pairs allowed to distinguish the 4 inbred lines on the basis of their banding patterns, reflected the evolutionary distance of the inbred lines and provided evidence as to the origin of these chromosomes in hybrids.Sister chromatid differentiation by means of BrdUrd incorporation prior to fluorescence plus Giemsa(FPG)-technique revealed 3.7 SCEs per cell for the hybrid BEKOS 251. Individualization of chromosomes on the basis of their replication patterns or asymmetric bands after application of the same technique was impossible.

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Differentialfärbung mitotischer Chromosomen von Inzuchtlinien und deren Hybriden beiZea mays L.

Zusammenfassung Die Giemsabandenmuster der vier Inzuchtlinien des Maises DB1113, DB1116 (convar.vulgaris) und WIR27, WIR44 (convar.dentiformis) sowie der daraus entstandenen Hybriden SU 10, Kappa und BEKOS 251 wurden untereinander verglichen. Polymorphismen des Knob-Heterochromatins auf vier Chromosomenpaaren (I, VI, VII, VIII) erlaubten die Unterscheidung der vier Inzuchtlinien anhand ihrer Bandenmuster, widerspiegelten den jeweiligen Verwandtschaftsgrad zwischen den Inzuchtlinien und ermöglichten für einige Chromosomen der Hybriden den Herkunftsnachweis.Schwesterchromatidendifferenzierung nach BrdUrd-Einbau und FPG-Färbung ergaben für die Doppelhybride BEKOS 251 3.7 SCEs/Zelle. Die Erfassung von Replikationsmustern oder asymmetrischen Banden zur Charakterisierung individueller Chromosomen war mit dieser Methode nicht möglich.

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Zea mays L.

, , DB1113, DB1116 (convar.vulgaris) WIR27, WIR44 (convar.dentiformis), SU 10, Kappa BEKOS 251. - (I, VI, VII, VIII) , . BrdUrd FPG BEKOS 251 3,7 . .

     

Resistance in Cucurbita pepo and Cucurbita maxima germplasms to cucumber mosaic virus

Summary A total of 384 Cucurbita pepo and Cucurbita maxima accessions were evaluated in growth chambers or glasshouse tests for resistance to cucumber mosaic virus (CMV). Seedlings were mechanically inoculated at the cotyledon stage, and scored for symptoms on cotyledons and true leaves 7 and 18 days after inoculation. Significant variation in resistance was found. A limited number of accessions were free of visual symptoms of infection. One C. pepo accession and thirteen C. maxima accessions showed a high level of resistance. Generally, C. maxima may be considered more resistant to CMV compared to C. pepo. There is no close relationship between origin, fruit morphotypes and CMV resistance in either species. Some accessions (e.g., C. pepo PI 438699; C. maxima PI 176530, PI 265555, PI 368564, PI 500483) could be useful for the future breeding programmes. The C. pepo cvs. Cinderella and Defender F1, previously described as resistant, showed maximum susceptibility to the yellow strain of CMV.Abbreviations CMV cucumber mosaic virus - WMV watermelon mosaic virus - ZYMV zucchini yellow mosaic virus - CYVV clover yellow vein virus - ZYFV zucchini yellow fleck virus     

Genetic diversity in cucumber (Cucumis sativus L.): II. An evaluation of selected cultivars released between 1846 and 1978

Genetic variation among 155 U.S. modern and heirloom cultivars was assessed from assays of 21 polymorphic isozyme loci. Four loci (Fdp-1, Mdh-1, Mpi-1 and Pgd-1) were monomorphic. Multivariate analyses partitioned cultivars into two distinct groups: those released before 1968, and those released after 1968. Cluster analysis produced a dendrogram with 14 nodes and 28 groups. Modern U.S. and European cultivars released after 1968 differed in isozyme frequencies. Isozymic profiles clearly discriminated some cultivars with unique attributes and/or pedigrees [e.g., Windermoor Wonder (USA), Gergana (The Netherlands), Seiram (The Netherlands), Fancy Pak (USA), Dasher 2 (USA), and WI 2757 (USA)].     

Der Einfluß von Wind und Windschutz auf den CO2-Gehalt der bodennahen Luftschicht über Feldkulturen

Zusammenfassung Mit Hilfe des Ultrarotabsorptionsschreibers (URAS) wurde die CO₂-Konzentration in der bodennahen Luftschicht unter dem Einfluß von Wind und Windschutz gemessen. In der Nacht ist die CO₂-Konzentration im Windschutz gegenüber dem Freiland erhöht, da dort die Atmungskohlensäure vor Verwehung geschützt ist. Bei unbewachsenem Boden bleibt jedoch in Lee die CO₂-Konzentration durch Behinderung der Zufuhr aus der Umgebung geringer als in Luv. Für den Verlauf des Aufbaues eines CO₂-Gefälles vom Boden her ist die Höhe der Windgeschwindigkeit bestimmend. Das rasche Absinken der CO₂-Konzentration in den Morgenstunden muß zuerst durch die Photosynthese, die schon kurz nach Sonnenaufgang einsetzt, verursacht werden. Nach Erwärmung der untersten Luftschichten geht dann durch den Vertikalaustausch der größte Teil des während der Nacht angesammelten Kohlendioxyds den Pflanzen für die Photosynthese verloren. Am Tage besteht im Windschutz gegenüber dem Freiland meist ein CO₂-Defizit, das zeitweise durch die erschwerte Erneuerung der Bestandesluft durch Advektion, in erster Linie jedoch durch die stärkere Assimilation der Pflanzen in Lee zustande kommt. Diese Mitteilung wird durch eine weitere ergänzt werden, welche das photosynthetische Verhalten von Pflanzen mit und ohne Windschutz behandelt.

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CO₂-content in the air layer above the ground with crop cultures in open field and under the lee

Summary By means of ultra-red absorption recorder (URAS) the CO₂-concentration of the air near the ground under the influence of wind and wind shelter was investigated. During the night the CO₂-concentration under the lee has been found increased in comparison with open field. Behind a shelter the CO₂ is not so much blown away as outside. Indeed, above soil without any plant growth the CO₂-concentration inside the sheltered area remains lower in consequence of the hindrance of horizontal transport of air. The wind speed is important to the formation of a CO₂-gradient above the ground. The rapid decrease of CO₂-concentration in the early morning must be caused primarily by photosynthesis of plants beginning almost immediately after sunrise. Later on by vertical air movement the greatest part of CO₂, accumulated during the night, is lost for photosynthesis by warming the air near the ground. During the day under the lee there exist mostly a CO₂-deficite in comparison with the open field. This is partly rendered by difficulty of air transport by advection, at first, indeed, by an increased rate of photosynthesis under the lee. The present communication will be continued by a second one concerning the photosynthetic behaviour of plants inside and outside of wind shelter.

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CO₂

, (URAS), CO₂ . CO₂ , , , , , . , , CO₂ , . CO₂ . CO₂ , . , , , , . , , CO₂, , . — .

     

Response of A-genome cotton germplasm to the seedling disease pathogens,Rhizoctonia solani and Pythium ultimum

Summary Approximately two hundred A-genome cotton (Gossypium arboreum L. and G. herbaceum L.) accessions were evaluated for resistance to the seedling disease pathogens Rhizoctonia solani Kühn [Thanatephorus cucumeris (A. B. Frank) Donk], and Pythium ultimum Trow. Susceptibility rating was based on a scale of 1 to 6 where 1 = no symptoms and 6 = dead. Variation was found among A-genome accessions in response to R. solani and P. ultimum, but none were highly resistant to these pathogens. As a group, the A-genome cottons were more susceptible to the pathogens than the G. hirsutum control.Abbreviations STV-A G. hirsutum Stoneville 506 with agar only - STV-NP G. hirsutum Stoneville 506 with non-pathogenic isolate - STV-P G. hirsutum Stoneville 506 with pathogenic isolate - A₁ G. herbaceum - A₂ G. arboreum - GRIN Genetic Resources Information Network     

Einige Bemerkungen zum Internationalen Code der Nomenklatur für Kulturpflanzen

Zusammenfassung Die Benennungssysteme für Kulturpflanzen und Wildpflanzen unterscheiden sich in wesentlichen Grundsätzen. Zu einigen Artikeln (15, 19, 26, 36) des Internationalen Code der Nomenklatur für Kulturpflanzen wird Stellung genommen.

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Summary The naming systems for cultivated plants and wild plants are different in important principles. Some articles (15, 19, 26, 36) of the International Code of Nomenclature for Cultivated Plants are discussed.

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am ¶rt;au . (15, 19, 26, 36) .

     

Evaluation of ‘di Romagna’ and ‘Frenchgrey’ shallots for quality characters connected to bulb colourand volatile oil content and composition

Local landraces of shallot from the Romagna region(Northern Italy) and North-western France, called Scalogno di Romagna and French grey,respectively, have recently been evaluated for morphological,biochemical and molecular characters. These populations appeared very different from common shallots and onions, so were re-classified as Allium oschaninii O.Fedtsch., whereas almost no variability was observed within these types. Four di Romagna and three French accessions were grown in Italy, and further evaluated for quality characters such asbulb colour and volatile oil content and composition. Colour was measured by means of a tristimulus colorimeter. Volatile oil was extracted by hydrodistillation and its components separated and identified by GC/MS. Colour parameters differentiated thedi Romagna from the French greyaccessions. Essential oil composition differed from what has been reported for most other Alliums, by a lower amount of1-propenyl- substituents. No individual oil component allowed a good differentiation of the two geographic origins.However, the French and di Romagna accessions were perfectly separated by the discriminant analysis of oil composition.Minor 1-propenyl- components seemed more critical for discrimination. The shallot types examined seemed biochemically differentiatedfrom Allium cepa. Variation in the examined quality characters was detected both between the two provenances and among the accessions of common geographic origin.     

Genetic diversity of Musa diploid and triploid accessions from the Brazilian banana breeding program estimated by microsatellite markers

Banana (Musa spp.) is one of the most consumed fruits worldwide. Production is based mainly on triploid cultivars, and most genetic improvement programs aim to generate tetraploid hybrids obtained from the crossing of established triploid cultivars with a diploid parent genotype, improved or wild, exhibiting the trait of interest, normally resistance to biotic factors. Microsatellites were used to investigate the genetic variability and relationships between 58 Musa genotypes, including 49 diploids and nine triploid cultivars maintained at the Musa germplasm collection of the Brazilian dessert banana breeding program. Thirty-three primer pairs developed for banana were tested, and nine amplified reproducible and discrete fragments, producing a total of 115 alleles. The average number of alleles amplified per primer was 12.8, ranging from 10 to 15. The diploid genotypes presented the largest genetic variability, demonstrated by the large number of alleles detected, and the low similarity between the clones. The phenetic analysis clustered the triploid cultivars in a separated group, with the exception of the Nanica and Gros Michel cultivars, which showed high similarity with the diploid cultivar Mambee Thu. It was not possible to separate the wild diploid genotypes from the cultivated ones, indicating a common origin of these genotypes. A high proportion of duplicated alleles and/or loci was observed for diploid and triploid genotypes. The information gathered about the similarity between diploid and triploid accessions will help to define potential crosses to maximize the recovery of the typical fruit qualities required in Brazil (AAB, Pome and Silk dessert banana).     

Problems ofPapaver somniferum-classification and some remarks on recently collected European poppy land-races

Summary The principles of formal classification of cultivated plants are discussed with reference toPapaver somniferum. This species can be divided into 3 subspecies-the ancestral wild race ssp.setigerum (Dc.)Corb. and the two cultivated races ssp.somniferum and ssp.songaricum Basil. differing in geographical distribution and characters of the stigmatic lobes. In both of the cultivated races two convars are accepted on the basis of their indehiscent vs. shattering capsules. Varieties are defined according toDanert (1958) using seed- and flower-colours.Poppies, recently collected in parts of central Europe, are classified according to the proposed system. Unlike other crops, very variable land-races of poppies can still be found in this region. About 20 percent of the totally accepted varieties could be found, containing also races from ssp.songaricum and types with shattering capsules. The handling and maintaining of this material in the Gatersleben gene-bank is briefly discussed.

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Probleme der Klassifikation vonPapaver somniferum und einige Bemerkungen zu unlängst gesammelten europäischen Mohn-Landsorten

Zusammenfassung Grundzüge der formalen Klassifikation von Kulturpflanzen unter besonderer Berücksichtigung vonPapaver somniferum werden diskutiert. Diese Art kann in drei Subspecies aufgegliedert werden — die wilde Ausgangssippe ssp.setigerum (DC.)Corb. und die beiden Kultursippen ssp.somniferum und ssp.songaricum Basil., die sich durch ihre geografische Verbreitung und Merkmale der Narbenscheiben voneinander abgrenzen lassen. In beiden Kultursippen werden je zwei Convarietäten unter Zugrundelegung ihres Schließ- bzw. Schüttmohncharakters unterschieden. Varietäten werden nachDanert (1958) anhand der Samen- und Blütenfarben definiert.Die in jüngster Zeit in einigen Teilen Zentraleuropas gesammelten Mohne werden nach dem vorgeschlagenen System klassifiziert. Im Gegensatz zu anderen Kulturpflanzen können in diesen Gebieten noch sehr variable Mohn-Landsorten gefunden werden. Ungefähr 20% der im System aufgeführten Varietäten konnten gesammelt werden, einschließlich einiger Vertreter der ssp.songaricum und von Schüttmohnsippen. Die Bearbeitung und Erhaltung dieses Materials in der Genbank Gatersleben wird kurz diskutiert.

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Papaver somniferum

, ë Papaver somniferum. ë : — ssp.setigerum (DC.)Corb. — ssp.somniferum ssp.songaricum Basil., . (convarietas) — . , (1958) . , , . , ë . 20% , ë , ssp.songaricum . .

     

Vorarbeiten zur monographischen Darstellung von Wildpflanzensortimenten:Agrostemma L.

Zusammenfassung Agrostemma githago ist ein typisches Saatgut-Unkraut, das zu den Segetalarten mit konvergentem Entwicklungstyp gehört; es hat sich in seinen Samenmerkmalen an die von ihm begleiteten Kulturpflanzen, vor allem an Getreide, anpassen können und ist dabei selbst Domestikationsvorgängen unterworfen worden. Dadurch ist es zu Adaptationen gekommen, wie sie vor allem bei der Evolution sekundärer Kulturpflanzen (z. B. Roggen, Hafer) eine Rolle gespielt haben.A. githago kann somit als Modellobjekt zur Untersuchung der Evolutionsvorgänge bei derartigen Kultursippen herangezogen werden.Heute gehört die früher weit verbreitete Segetalpflanze, bedingt vor allem durch bessere Methoden der Saatgutreinigung, vielerorts zu den vom Aussterben bedrohten Arten. Zahlreiche Sippen, besonders von Sammelreisen, werden daher in die Gaterslebener Genbank aufgenommen, und eine umfangreiche Kollektion wurde zusammengetragen, die gegenwärtig etwa 100 Sippen umfaßt. Die Methoden zur Erhaltung dieses Materials, das die Basis für die vorliegenden Untersuchungen bildet, werden dargelegt.In den Jahren 1977 bis 1980 wurden an je 10 Pflanzen jeder angebauten Sippe quantitative Merkmale ermittelt. Es erfolgte die Berechnung der statistischen Kenngrößen (Mittelwert, Varianz, Streuung, Variationskoeffizient, Korrelationsmatrizen) für das gesamte Material und die Einzelsippen. Unter Zuhilfenahme dieser Ergebnisse wurde die GattungAgrostemma revidiert und zwei Arten,A. brachylobum (Fenzl) Hammer (2x =24) undA. githago L. (4x=48), anerkannt, die sich auch anhand morphologischer Merkmale deutlich unterscheiden. BeiA. githago ist die var.linicohim (Terech.) Hammer, mit kleinen, ±glatten Samen, an die Leinkultur angepaßt, und die großsamige var.macrospermum (Levina) Hammer kommt überwiegend im Weizen vor. Innerhalb der var.githago deuten sich weitere Evolutionsrichtungen an, wie die Anpassung an Wicken oder Buchweizen. In neuerer Zeit sind Vertreter dieser Sippe mit relativ kleinen Samen häufiger als Ruderalpflanzen zu finden.Das GaterslebenerAgrostemma-Sortiment bietet gute Möglichkeiten für die botanische Grundlagenforschung und kann gleichzeitig einen Beitrag zum Artenschutz leisten.

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Studies towards a monographic treatment of wild plant collections:Agrostemma L.

Summary Agrostemma githago is a typical seed weed belonging to the segetal species of the so-called convergent evolutionary type; its seed characters are adapted to those of the cultivated species (mainty cereals), which are accompanied by the corn cockle. In the course of cereal domestication the weed has been domesticated too and developed certain adaptations characteristic for secondary cultivated plants (as e.g. rye, oats). Therefore this weed species can be used as a model for studying evolutionary processes in such cultivated species.Today the formerly widespreadA. githago belongs to the species threatened with extinction, mainly due to improved methods for seed cleaning. Therefore different races of this weed mostly gathered by collecting missions are included into the Gatersleben gene bank and a comprehensive collection has been built up comprising now about 100 accessions. Methods for maintaining of this collection are discussed; this material is used as the basis for the present investigations.From 1977 to 1980, quantitative traits of 10 plants of all the cultivated accessions have been recorded. The statistical analysis carried out for every year included the calculation of means, variances, standard deviations, coefficients of variation and correlation matrices for the single accessions and the complete collection. Using these results the genusAgrostemma has been revised and two species are accepted —A.brachylobum (Fenzl) Hammer (2x=24) andA. githago L. (4x=48) — which can be easily distinguished also by morphological characters. WithinA. githago the var.linicolum (Terech.)Hammer with small ±smooth seeds is adapted to flax and the large-seeded var.macrospermum (Levina) Hammer grows mainly in wheat fields. Further evolutionary trends can be traced within the var.githago, e.g. adaptations toVicia spp. or buckwheat. Plants with relatively small seeds nowadays can be found more frequently at ruderal sites.The GaterslebenAgrostemma collection provides good possibilities for the use in basic botanical research and simultaneously for the protection of an endangered species.

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:Agrostemma L.

Agrostemma githago , . , , . , , , (. , ). , . - , , , , , . , , , 100 . , . 1977–1980 . 10 . (, , , , ) , . Agrostemma :A. brachylobum (Fenzl) Hammer (2x=24) A. githago L. (4x=48), . A. githago , ± , var.linicolum (Terech.) Hammer, , var.macrospermum (Levina) Hammer . var.githago , . ( ) . .

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Herrn Prof. Dr. Dr. h. c. mult. H.Stubbe aus Anlaß der 80. Wiederkehr seines Geburtstages gewidmet.     

Untersuchungen zur Stabilität und Vitalität an Systemen balancierter tertiärer Trisomie bei Gerste

Zusammenfassung Bei 112 Linien 25 verschiedener BTT-Systeme erwies sich die genetische Stabilität der Systeme in den meisten Fällen als gut bis sehr gut, gemessen an der Frequenz disom-fertiler Rekombinanten. In speziellen Kreuzungstests ergaben sich Hinweise auf mögliche Stabilitätsstörungen durch Pollentransmission des Zusatzchromosoms nur bei einem von neun geprüften Systemen.Die Vitalität der trisomen Pflanzen bei den verschiedenen BTT-Systemen ist sehr unterschiedlich und von der jeweils vorliegenden Segmentzusammensetzung des Zusatzchromosoms abhängig. Bezogen auf diploide Pflanzen gibt es alle Übergänge von Subletalität bis hin zu annähernd normaler Vitalität. Leistungsfähige BTT-Systeme sind relativ selten und können mit ausreichender Wahrscheinlichkeit nur entwickelt werden, wenn von einer genügend breiten Basis von Translokations-undmsg-Linien ausgegangen wird.

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Studies on the stability and viability in systems of balanced tertiary trisomy in barley

Summary The genetic stability of 112 stocks out of 25 different BTT systems proved to be, in most cases, good to very good, in terms of the frequency of disomic fertile recombinants. There is only rare indication of instability caused by pollen transmission of the extra chromosome: In special crossing tests only one out of nine BTT systems tested showed transmission.The viability of trisomic plants is very diverse in the different BTT systems and depends on the specific segmental composition of the extra chromosome. As compared with normal diploids there are all types of trisomics ranging from sublethal to nearly normal ones. Efficient BTT systems are comparatively rare. They can be developed with good expectation provided a sufficiently broad basis of translocation andmsg lines is used.

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112 25 . - . . - , 9 . . , . , , , msg-.

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Herrn Professor Dr. Dr. h. c. mult.H. Stubbe zum 85. Geburtstag gewidmet.     

Taxonomy and evolution of cultivated plants: Literature review 1982/1983

Summary Important papers on taxonomy and evolution of cultivated plants published in 1982 and 1983 were compiled and briefly discussed.

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Taxonomie und Evolution der Kulturpflanzen: Literaturübersicht 1982/1983

Zusammenfassung Wichtige Arbeiten über Taxonomie und Evolution der Kulturpflanzen aus den Jahren 1982 und 1983 wurden zusammengestellt und kurz kommentiert.

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: 1982–1983

, 1982 1983 . .

     

Zymogram patterns of α-amylase isozymes inEthiopian tetraploid wheat landraces: insight into their evolutionaryhistory and evidence for gene flow

The variation for -amylaseisozymes was analyzed in 71 tetraploid wheat (AABB genome)landraces from Ethiopia, including accessions of Triticumdicoccon Shrank, T.turgidum L., T.durum Desf., T.pyramidale Percival and T.aethiopicum Jakubz., by thin-layerpolyacrylamide gel isoelectric focusing. Four zymogram phenotypeswere obtained from all the materials studied. Except inT. dicoccon, however, thestandard pattern of the durum wheat variety, LD222, was predominant.T. dicoccon showed twozymogram types that differed for the absence or consistently weakactivity of band 18(-Amy-B1)of the malt type. Band 1(-Amy-B3)of the malt type was fixed in T.dicoccon and present in only 10% of thefree-threshing (FT) types. Generally, the resultsindicated that the variation for-amylase isozymes in cultivatedtetraploid wheats, including landraces from secondary centers, is lowpossibly due to the founder effect or as a result of selection. Thedata were useful for inferences about the evolutionary history ofEthiopian wheat landraces. It is speculated thatT. dicoccon was the firstwheat to arrive in the Ethiopian highlands ca.5000 years ago. However, it is not known whether the present day FTEthiopian tetraploid wheat landraces are direct descendants ofT. dicoccon, or whetherthey were introduced independently. The clear differences in-amylase zymogram patterns favor the latterhypothesis. However, the presence of band1 in some of the FT types indicated the occurrence of geneflow between the FT types and T.dicoccon, which may also explain thequantitative nature of spike threshability in these landraces.Possible implications for durum wheat breeding arediscussed.     

Evaluation of Gossypium arboreum L. Germplasm for resistance to thrips

Summary As part of a project to assess the U.S. Asiatic Cotton Germplasm Collection as a source of genes for pest resistance, forty-three accessions of Gossypium arboreum L. were evaluated for resistance to thrips. Thrips, Thysanoptera spp., are a minor, but widespread pest on cotton, G. hirsutum L. and G. barbadense L. Accessions were planted in free-choice field tests in 1988, 1989, and 1990 at the Cotton Branch Experiment Station, Marianna, Arkansas. Damage ratings, based on a scale of 0 (no damage) to 7 (severe damage), were made approximately one month after planting. Relative score was computed by dividing the rating of each accession by the rating of the reference, G. hirsutum Stoneville 506. The relative score averaged over all G. arboreum accessions by year varied with the year, but was less than 100 (relative score for Stoneville 506) in each case. When data were combined for all three years, twenty-five accessions were significantly better than Stoneville 506. Introgression of the better accessions into G. hirsutum is now in progress.Abbreviations NPGS National Plant Germplasm System - STV 506 G. hirsutum Stoneville 506     

The Cuban homegarden ‘conuco’: a perspective environment for evolution and in situ conservation of plant genetic resources

Summary Cuban homegardens are called conucos. On the basis of new case studies additional information is provided about these conucos, their history, composition and importance. They and other gardens of similar type are characterized as suitable environment for in situ conservation and for the continuation of evolutionary processes.     

RAPD and seed coat morphology variation in annual and perennial species of the genus Cicer L.

Molecular and morphological variation of six perennial and five annual species including domesticated chickpea, C. arietinum, were inferred on the basis of RAPD and S.E.M. seed coat features using three outgroup taxa (Lens ervoides, Lathyrus japonica and Pisum sativum). Of the 66 decamer arbitrary primers tested, eight primers revealed 87 informative fragments. Neighbor-joining cluster analysis using Jaccard's coefficient of similarity on the basis of polymorphic fragments indicated a narrow variation in C. arietinum and recognized two major clusters in the genus Cicer. The first one included four species of sect. Monocicer: C. echinospermum, C. arietinum, C. reticulatum and Iranian material of C. bijugum. The second cluster contained annual and perennial species belonging to sections Chamaecicer, Polycicer and Acanthocicer. The character state of morphological and ecological traits on the RAPD phenogram indicated no monophyletic incision. Our results suggested that the high genetic difference between annual and perennial species might be regarded as a rapid speciation of section Monocicer. Reconsideration of traditional classification of sections Polycicer and Acanthocicer is necessary. The Desi and Kabuli types of C. arietinum could not be separately grouped at the DNA level, and the low level of genetic variation of C. arietinum may result from a bottleneck during the domestication process.