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Not necessarily all cells of an organism contain the same genome. Some eukaryotes exhibit dramatic differences between cells of different organs, resulting from programmed elimination of chromosomes or their fragments. Here, we present a detailed analysis of programmed B chromosome elimination in plants. Using goatgrass Aegilops speltoides as a model, we demonstrate that the elimination of B chromosomes is a strictly controlled and highly efficient root-specific process. At the onset of embryo differentiation B chromosomes undergo elimination in proto-root cells. Independent of centromere activity, B chromosomes demonstrate nondisjunction of chromatids and lagging in anaphase, leading to micronucleation. Chromatin structure and DNA replication differ between micronuclei and primary nuclei and degradation of micronucleated DNA is the final step of B chromosome elimination. This process might allow root tissues to survive the detrimental expression, or overexpression of B chromosome-located root-specific genes with paralogs located on standard chromosomes., B chromosomes are supernumerary chromosomes exhibiting dramatic differences between different organs in same species. Here, the authors show programmed B chromosome elimination in goatgrass starts at the onset of embryo differentiation by nondisjunction of chromatids, anaphase lagging, and ends with the degradation of micronucleated DNA.

The situation of plant genetic resources in southwestern Georgia is illustrated using the material from a 2010 collecting mission of the Tbilisi Botanical Garden and Institute of Botany and the Leibniz Institute of Plant Genetics and Crop Plant Research (IPK), Gatersleben, after having finished seed reproduction and plant characterization. Despite increased genetic erosion in the region, especially in field crops, 295 accessions of local cereals, vegetables, pulses, spices and medicinal plants could be collected. Variable landraces of winter annual Triticum aestivum L. are still cultivated in several villages of Mescheti, comprising up to six different morphological varieties. Relic crops, such as Linum usitatissimum L. in Džavacheti and Pisum sativum L., Glycine max (L.) Merr. or Brassica oleracea L. var. viridis L. in Atcara could be collected. A tremendous variability of Phaseolus vulgaris L. is grown in the whole area as the main pulse crop.

In western Germany, typical gardens of immigrant families were visited and periodically checked regarding their plant composition and cultivation techniques. A preliminary inventory of the cultivated plants of the Langenberg region south of Bonn is given. Chaerophyllum byzantinum Boiss. and Trachystemon orientalis (L.) G. Don as new crops, recently introduced from the wild flora of Turkey, and their utilization are shortly described. Most gardening immigrants originate from farmers’ families and introduce local knowledge from their native countries. Personal preferences to familiar or local varieties made them transfer the respective seeds or plants and in some cases even wild plants to their new settling areas. Vicinity to German or immigrant gardeners from other nationalities allowed for exchange of seed and experience. This way, German gardens became centers of increasing diversity for horticultural crops within the past few decades.

The recent treatment of Triticum by Mac Key (2005) (broad species concept) is compared to the classical treatment by Dorofeev et al. (1979, English translation expected) (narrow species concept). A detailed infraspecific treatment was abandoned by Mac Key. Following his revision, names for many of the infraspecific taxa become obsolete. This is regarded to be a disadvantage for biodiversity and genetic resources studies. We propose maintaining ×Triticosecale Wittm. as a nothogenus, with ×T. rimpaui Wittm. for octoploid races, ×T. neoblaringhemii A. Camus for hexaploid races and ×T. semisecale (Mac Key) K. Hammer et A. Filat. (new combination) for tetraploid races.

In the grass tribe Poeae a small group of taxa occur with an exceptionally low chromosome number of 2n = 2x = 4 belonging to the closely related genera Colpodium and Zingeria. To understand the formation of polyploids in this group we analyzed the evolution of allohexaploid Zingeria kochii (2n = 12) and its presumable ancestral species. Genomic in situ hybridization demonstrated that Z. kochii evolved from an interspecific hybrid involving species closely related to contemporary Z. biebersteiniana (2n = 4) and Colpodium versicolor (2n = 4) and a third unknown species. Following allopolyploidization of Z. kochii the biebersteiniana-like parental chromosomes underwent loss of ribosomal DNA. No interlocus homogenization of 45S rDNA took place in Z. kochii and phylogenetic analysis showed that C. versicolor contributed its genome to Z. kochii relatively recently. In situ hybridization was particularly effective in understanding the allopolyploid evolution in Zingeria while the analysis of ITS sequences alone would have resulted in a wrong interpretation of the allopolyploid history of the genus.

The continued cultivation of Lupinus pilosus L. as an endemic coffee substitute in the mountain village of Altrei, South Tyrol, located in the Val di Fiemme/Fleimstal valley ca. 24 km south of Bolzano/Bozen, since the middle of the nineteenth century is demonstrable. Former reports of cultivation of Lupinus cosentinii Guss. and L. varius auct., non L. for this purpose in Tyrol could refer to L. pilosus as well. The cultural history of the rare crop is summarized up to its recent revival.

Nuclear DNA amounts of 118 cultivated fonio accessions representing 94 landraces collected from the major growing areas of West-Africa (Benin, Burkina Faso, Guinea, Mali and Togo) and eight accessions of four wild relatives were investigated by Laser flow cytometry. In cultivated species, average 2C-values ranged from 1.848 ± 0.031 pg for Digitaria iburua to 1.956 ± 0.004 pg for D. exilis. In D. exilis landraces the chromosome number was determined at 2n = 36. The closely related wild species D. longiflora and D. ternata showed similar 2C DNA contents of 1.869 ± 0.035 pg and 1.775 ± 0.070 pg, respectively. Distinctly larger genomes were identified for more distant species D. lecardii and D. ciliaris with 2.660 ± 0.070 pg and 2.576 ± 0.030 pg per 2C nucleus, respectively. Intra-specific variations were found to be slight and insignificant, suggesting genome size stability mainly within the cultivated gene pool. These results support the distance of cultivated fonio species D. exilis and D. iburua from D. lecardii and D. ciliaris as well as their close relationships with D. longiflora and D. ternata. Relevance of the results for ploidy level considerations in fonio millets is discussed.

The C-value paradox remains incompletely resolved after >40 yr and is exemplified by 2,350-fold variation in genome sizes of flowering plants. The carnivorous Lentibulariaceae genus Genlisea, displaying a 25-fold range of genome sizes, is a promising subject to study mechanisms and consequences of evolutionary genome size variation. Applying genomic, phylogenetic, and cytogenetic approaches, we uncovered bidirectional genome size evolution within the genus Genlisea. The Genlisea nigrocaulis Steyerm. genome (86 Mbp) has probably shrunk by retroelement silencing and deletion-biased double-strand break (DSB) repair, from an ancestral size of 400 to 800 Mbp to become one of the smallest among flowering plants. The G. hispidula Stapf genome has expanded by whole-genome duplication (WGD) and retrotransposition to 1550 Mbp. Genlisea hispidula became allotetraploid after the split from the G. nigrocaulis clade ∼29 Ma. Genlisea pygmaea A. St.-Hil. (179 Mbp), a close relative of G. nigrocaulis, proved to be a recent (auto)tetraploid. Our analyses suggest a common ancestor of the genus Genlisea with an intermediate 1C value (400-800 Mbp) and subsequent rapid genome size evolution in opposite directions. Many abundant repeats of the larger genome are absent in the smaller, casting doubt on their functionality for the organism, while recurrent WGD seems to safeguard against the loss of essential elements in the face of genome shrinkage. We cannot identify any consistent differences in habitat or life strategy that correlate with genome size changes, raising the possibility that these changes may be selectively neutral.

Eryngium caucasicum was found as a new cultivated vegetable plant in home gardens in northern Iran. Young leaves are used as a cooked vegetable and for flavouring in the preparation of several local foods.

Dispensable, supernumerary (B) chromosomes are found in diverse eukaryotic species. The origin and genetic consequences of B chromosomes have been the subjects of speculation for more than a century. Until now, there has been no molecular evidence that B chromosome DNA is transcribed and there is no unequivocal evidence as to their origin. B chromosomes are considered to be genetically inert although they appear to cause a variety of phenotypic effects. We report that members of one of two ribosomal RNA gene families that are confined to the B chromosomes of a plant, Crepis capillaris, are transcribed—thus providing the first molecular evidence of gene activity on B chromosomes. Sequence analysis of part of the A and B chromosome rRNA genes, together with comparisons with related species, indicates that the B chromosome rRNA genes originate from the A chromosome.

— Agenome size of 2C = 235 Mbp and the chromosomal positions of the 5S and 45S rDNA were determined for the perennial, low-chromosome grass Colpodium versicolor (2n = 4). Based on taxonomical and cytological data we suggested previously that C. versicolor represents a putative donor of one of the two parental genomes of the allotetraploid grass Zingeria trichopoda (2n = 8). To test this hypothesis sequence comparison of the ITS1-5.8S-ITS2 -region (part of the 18S rDNA) and genomic in situ hybridization were performed. Although the ITS1-5.8S-ITS2 sequences of C. versicolor and Z. trichopoda are highly similar, genomic in situ hybridization of Z. trichopoda with labeled genomic DNA of C. versicolor did not result in a subgenome-specific labeling of Z. trichopoda chromosomes. Thus, the contemporary species C. versicolor is a closely related but not the direct ancestor of the allopolyploid species Z. trichopoda.

A general index of the second 25 volumes of 'Kulturpflanze' 1978–1990/'GRACE' (Genetic Resources and Crop Evolution) 1992–2003 is provided. Its predecessor covered the first 25 volumes of the periodical 'Die Kulturpflanze' and appeared in 1977. The index can be considered as a unique source for research in plant genetic resources.

Summary Early floral organogenesis has been investigated in a number of Allium species from various subgenera and sections (A. ramosum, A. angulosum, A. galanthum, A. sphaerocephalon, A. oreophilum, A. cernuum, A. moly). Comparative studies and earlier results show a considerable uniform pattern of the sequence of floral organ inception in the genus as a whole. Fusion of extended filament bases and shifting outwards of the originally inner stamina has been observed in Allium oreophilum after stamina differentiation only. A disturbance of alternation in the androeceum has been detected in Allium kujukense, A. umbilicatum, and A. ferganicum as well. Those configurations and that of Trillium apetalon can be described by the term “obdiplostemony”, applied in a broad sense also to flowers with a perianth, not differentiated into calyx and corolla. According to this definition, mature flowers with two stamen whorls are obdiplostemoneous in the case of an interrupted alternation between androeceum and perianth, with stamina of the outer stamen whorl opposite the parts of the inner whorl of the floral envelope and/or stamina of the inner stamen whorl opposite the parts of the outer whorl of the floral envelope. In the genus Allium obdiplostemony occurs in several subgenera and sections of different flower traits. In the case of Allium oreophilum and A. kujukense however, a special type of obdiplostemony suggests a close relationship.

A joint exploring mission has been carried out by staff members of the Institute of Botany of the Uzbek Academy of Sciences, Taskent and the Institut fur Pflanzengenetik und Kulturpflanzenforschung, Gatersleben, in July/August 1995 to study plant genetic resources in a remote mountainous area of south-western Hissar, Uzbekistan. Subsistence farmers of the Tupalang basin are still growing a great number of landraces and local varieties, which could be investigated for the first time in that area. In total 238 accessions, mainly of cereals, vegetables, pulses, spices and medicinal plants, were collected. Of special interest has been indigenous material of wheat, barley, turnip, chickpea, pea, lentil, small-seeded linseed as well as some wild spices and medicinal plants.

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.

Important papers on taxonomy and evolution of cultivated plants published in 1988 and 1989 were compiled and briefly discussed.

Calamintha nepeta and Micromeria thymifolia have been traditionally used in the Mediterranean area as condiments and medicinal plants for a long time. Whereas in parts of Italy C. nepeta (special recipes have been developed in Lazio and Tuscany) is also an established garden plant showing different evolutionary products and their interaction among each other and the wild progenitor, M. thymifolia is being developed into a new crop plant. Both plants and their uses are described with regard to Italy. There is a marked tendency to broaden the use of condiments and spices which results in new crop plants which have to be documented and elaborated in further studies. Many species of Labiatae are predisposed to use by man and new items can be found even in areas which have to be considered as well studied.

Important papers on taxonomy and evolution of cultivated plants published in 1987 and 1988 were compiled and briefly discussed.

Eine Sammelreise von Mitarbeitern des Instituts fur Botanik Ulan-Bator und des Zentralinstituts fur Genetik und Kulturpflanzenforschung Gatersleben in den Osten der MVR vom Juli/August 1987 galt der weiteren Inventarisierung der Gefaspflanzen dieses Gebiets und den indigenen Wildsippen der GattungAllium L. im besonderen. Uber Verlauf und erste Ergebnisse der Expedition wird kurz berichtet. DieAllium-Pflanzgutproben werden aufgelistet. Fur verschiedene Arten(Allium macrostemon, A. neriniflorum, A. condensatum, A. polyrrhizum, A. mongolicum, A. ramosum) folgen Bemerkungen zur systematischen Stellung, Verbreitung und Standortscharakteristik in der Ostmongolei. Auf Nutzung und Kultur mongolischerAllium-Arten wird abschliesend kurz eingegangen.

Important papers on taxonomy and evolution of cultivated plants published in 1979 and 1980 were put together and briefly discussed.

Important papers on taxonomy and evolution of cultivated plants published in 1983 and 1984 were complied and briefly discussed.

Important papers on taxonomy and evolution of cultivated plants published in 1985 and 1986 were compiled and briefly discussed.

After having finished in 1985 the collection of plant-genetic resources in Western Georgia (the results have been summarized in some tables) joint activities for the collection of indigenous taxa of cultivated plants began for Eastern regions of the Georgian SSR in 1986. The mission took place within the rayon Duseti, which is highly differentiated in geographical respect and stretches beyond the main ridge of the Great Caucasus. Althogether 265 samples could be collected, grain legumes and vegetables represent the most numerous groups but the amount of cereal accessions is not much less; this contrasts sharply with the results from the missions in Western Georgia. The gene-erosion is very advanced in Duseti too, especially for cereals.Triticum carthlicum, T. dicoccon and naked barleys have disappeared within the last decades from the fields. However in isolated settlements the cultivation of old local races ofT. aestivum as well as of barley and rye had been maintained up till now. For breeding purposes and botanically interesting material could be collected also from vegetables, spice plants and grain legumes. Some examples have been shortly characterized.

In continuation of joint activities since 1981 in Western Georgia a further mission for studying and collecting indigenous forms of cultivated plants and their wild relatives has been carried out by staff members of the Institute of Botany, Tbilisi, and the Zentralinstitut fur Genetik und Kulturpflanzenforschung, Gatersleben, in September/October 1985. 445 accessions, mainly of legumes, vegetables, spice plants and maize could be collected in South-western Georgia (Adžaria, area around Boržomi). Gene-erosion is highly advanced for field crops (especially cereals), may be as a result of the specialization to subtropical cultures near the coast and to tobacco, respectively cattle-breeding in higher mountainous regions. But many local races of garden crops are still cultivated now. A large amount of indigenous taxa of cultivated plants, of potential value for plant breeding and botanically interesting, could be obtained. The collection work in the Georgian SSR should be continued.

Auf einer Reise in die westliche Slowakei konnte interessantes Material seltener Kulturpflanzen und Landsorten gesammelt werden (insgesamt 594 Proben, insbesondere Getreide und Leguminosen). Viele dieser Formen sind im Gebiet unmittelbar vom Aussterben bedroht.

Important papers on taxonomy and evolution of cultivated plants published in 1986 and 1987 were compiled and briefly discussed.

Summary Allium sect. Porphyroprason is a monotypic section comprising the species A. oreophilum, a petrophyte of the (sub)alpine belt from the Turkestanian Floristic Subregion with a few further localities in E Anatolia, E Caucasus and Dagestan. It is a summer-ephemeroidal plant which has been described in regard to its growth form, growing rhythm, anatomy (leaves, scape), testa structure and karyology. — The discussion of character relations of the species revealed several hints but morphological, anatomical, chorological and especially serological data advocate most strongly the inclusion of the section into subgen. Melanocrommyum. However it occupies a rather isolated position within this subgenus.

Important papers on taxonomy and evolution of cultivated plants published in 1984 and 1985 were compiled and briefly discussed.

Important papers on taxonomy and evolution of cultivated plants published in 1981 and 1982 were compiled and briefly discussed.

Allium-Arten gehoren zu den regelmasig und traditionell von der mongolischen Bevolkerung genutzten Wildpflanzen, die vor allem als Wurzmittel fur die sonst vorzugsweise auf tierischen Produkten beruhende Kost dienen. Besondere Bedeutung haben dabeiA. altaicum, A. victorialis undA. ramosum, bei denen die Sammlung von Zwiebeln bzw. oberirdischer Pflanzenteile nicht nur fur den individuellen Bedarf, sondern auch fur die Marktversorgung erfolgt. Als Ausgangsmaterial zur Herstellung eines Winterkraftfutters sindA. polyrrhizum undA. mongolicum in den Halbwustengebieten der MVR von hohem wirtschaftlichem Wert. Bei einigen Arten(A. altaicum, A. macrostemon) hat die intensive Nutzung zur Verringerung der naturlichen Bestande gefuhrt.

Das wahrend der Reise in ein Gebirgsgebiet der westlichen Slowakei 1981 (vgl.Kuhn et al. 1982) gesammelte Kulturpflanzenmaterial wird botanisch charakterisiert. Es handelt sich uberwiegend um Landsorten, alte Sortentypen und Kultursippen von oft sehr hoher Variabilitat, deren Anbau meist in raschem Ruckgang begriffen ist. Charakteristische indigene Formen konnten u. a. noch beiTriticum aestivum, Avena sativa, Papaver somniferum, Pisum sativum undPhaseolus vulgaris nachgewiesen werden. Bemerkenswert ist das Vorkommen ausgesprochener Reliktkulturen (z. B.Triticum dicoccon, Secale cereale var.multicaule, Panicum miliaceum, Cicer arietinum, Lathyrus sativus undFagopyrum esculentum). Die Gebirgsregion gehort zum Erhaltungsgebiet autochthoner Kulturpflanzen-Sippen in den Westkarpaten. Das rasche Fortschreiten der Generosion last eine baldige Fortfuhrung der Sammeltatigkeit notwendig erscheinen.

In the summer 1983 the joint activities for the collection of autochthonous material of cultivated plants have been continued in the outermost western regions of Georgia (Abkhazia, Megrelia). Altogether 434 accessions could be obtained, more than one third of them being grain legumes, and one fourth vegetables and spice plants, resp. The remaining part includes mainly maize. Gene-erosion is very advanced especially for cereals and some grain legumes besidesPhaseolus vulgaris for which an astonishing genetic variability could be confirmed within the local material. Some details of the accessions regarding botanical interest and breeding value have been outlined. The collecting work should be continued.

In continuation of recent collecting activities in the Georgian SSR a further mission has been carried out jointly by staff members of the Institute of Botany Tbilissi and the Central Institute for Genetics and Cultivated Plant Research, Gatersleben, in September 1988 for exploration and collecting plant genetic resources. The travel route covered in this year Kachetia (Eastern Georgia), including the Civi-Gomborskij range of Great Caucasus and the foothills of the main ridge bordering the Alazani and Iori river valleys. 318 samples, mainly of grain legumes, vegetables, spice plants and maize could be collected. The material represents variable land-races and indigenous taxa of cultivated plants from this area, which have been listed and characterized shortly for some examples.

Important papers on taxonomy and evolution of cultivated plants published in 1980 and 1981 were compiled and briefly discussed.

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