Chromosome number and genetic system in several Trifolium species related to T. alexandrinum

Chromosome counts have been done in 12 species of Trifolium, closely related to T. alexandrinum L., and the chiasma frequency in meiosis, pollen fertility, and seedset upon selfing was estimated. In all species, the basic number of chromosomes was 2n=16 arranged in eight bivalents. Two species, T. salmoneum Mout, and T. berytheum Boiss., have 0–7 B-chromosomes in eight out of nine plants examined. The frequency of B-chromosomes was somewhat correlated with pollen fertility. Chiasma frequency ranged between 10.8 and 16.1 per cell with specific and ecotypic differentiation. Except for T. alexandrinum, the species analyzed were completely (or, in a few cases, highly) self-incompatible.Contribution from the Volcani Institute of Agricultural Research, Bet Dagan, Israel. 1970 Series, No. 1677 E. This research was financed by a grant from the U.S.D.A. under P.L. 480, Contract A10-CR-56.     

Cytogenetic studies in Trifolium sp. related to berseem

Summary In a cytogenetic study of five annual Trifolium spp. the genetical relationships between (1) T. scutatum Boiss. and (2) T. plebeium Boiss., and between them and (3) T. carmeli Boiss., (4) T. echinatum M. B. and (5) T. latinum Seb., were studied in intra- and interspecific F₁ and F₂ hybrids. Germination, seedlings development, pollen fertility and chromosome configurations during meiosis and seedset were recorded. All the T. scutatum x T. plebeium F₁ were green, but the hybrids between either T. plebeium or T. scutatum and T. carmeli, T. echinatum or T. latinum were mainly albinos. Those that were green had a very high rate of mortality and the survivors produced many albino seedlings. Pollen fertility was about 60% in scutatum x plebeium F₁s, and one of their eight bivalents was heteromorphic. Hybrids between either of these and T. carmeli, T. echinatum or T. latinum had 30–50% stainable pollen and had several multivalents, suggesting the existence of a system of chromosomal translocations in these species. Seed set was roughly correlated with pollen stainability. The nature of the isolation mechanisms operating between these species is discussed.Contribution from the Volcani Center, Agricultural Research Organization, Bet Dagan, Israel. 1973 Series, No. 186-E. The work reported here was financed by Grant FG-IS-222 from the U.S. Department of Agriculture under P. L. 480.     

Cytogenetic studies in trifolium spp. related to berseem

Summary In order to clarify the interspecific relationships between T. carmeli Boiss., T. echinatum M.B. and T. latinum Seb., numerous F₁, F₂ and BC₁ hybrids of these species were raised, and their growth, pollen fertility, cytology and seedset were determined. T. carmeli was found to differ from both T. echinatum and T. latinum by at least three translocations, and their hybrids were semisterile as to pollen and seedset. T. latinum was more or less interfertile with T. echinatum and hybrids had normal meiosis, except for T. echinatum NYT 1401, whose hybrids with T. latinum were semisterile and evinced major chromosomal changes. Some implications of sterility and chromosomal heterogeneity are discussed. Backcrosses of T. echinatum × T. latinum F₁s to either parent resulted in partial breakdown of the self-incompatibility system found in both parental species and their F₁ hybrids.Contribution from the Volcani Center, Agricultural Research Organization, Bet Dagan, Israel, 1972 Series, No. 2207-E. The work reported here was financed by Grant FG-IS-222 from the U.S. Department of Agriculture under P.L.480.     

Biosystematic studies on the umbellatum-angustifolium complex of the genus Ornithogalum. (Liliaceae). II. Genome characterization and evolution

Chromosome banding techniques (Giemsa and fluorochrome staining) were used to investigate Ornithogalum umbellatum L., O. angustifolium Bor. and 11 related taxa. Nine different basic Q-banding patterns, referred to as genomes, could be recognised. These patterns are indicated by capitals (A–E, P–S). Six of the nine basic genome types can be subdivided into different subtypes. The B genome was found in the two bulbilliferous species, i.e. O. umbellatum and O. angustifolium. It occurs in a number of combinations together with the A, C, D and E genomes. Genome combinations of these five basic types were found in seven species. Six of them share morphological characteristics. These species are: O. monticolum Jord. & Fourr., O. baeticum Boiss., O. angustifolium, O. refractum, Kit., O. umbellatum and O. algeriense Jord. & Fourr. A seventh species, O. platyphyllum Boiss., in which the E genome occurs, can be regarded as an intermediate between this complex and the O. montanum group. Each species is treated extensively; its morphology, geographical distribution, chromosome number and banding patterns are discussed separately. A model of the probable course of the evolution in this complex during the last two glaciation periods is described. In this model attention is paid to ecological differentiation, migration leading to the present distribution patterns, hybridization followed by polyploidization and to fixation, which may be the result of chromosomal rearrangements that prevent regular meiosis. Some cytotypes, formerly regarded as O. umbellatum, are now classified in other species. A second polyploid complex in which these species occur, is probably more widely distributed in south-eastern Europe than is generally thought at present. The species O. exscapum Ten., O. nivale Boiss., O. comosum L., O. collinum Guss. and O. gussonei Ten. p.p. are components of this complex. The delimitation of this complex as a whole and the relationship between its diploid and polyploid components have still to be clarified.     

Crossability analysis in subgenus Tulipa of the genus Tulipa L.

A range of almost 1400 cross combinations has been carried out between 31 species of Tulipa subgenus Tulipa. Most of the sections are well separated reproductively from each other. The designated species aggregates in section Clusianae appeared to be intersterile. Also in section Kolpakowskianae the species, as far as used, cannot be combined. Some crosses between species of section Tulipanum succeeded. The species of sections Eichleres and Tulipa (including the cultivated tulip T gesneriana) could be combined in various ways, although the highest level of seed set was achieved within either section. The crossability data support the current taxonomic division. The level of reproductive isolation between sympatric species is discussed, and the importance of crossability studies for plant breeding in Tulipa pointed out briefly.     

Phylogeny of tall fescue and related species using RFLPs

The wild species of tall fescue (Festuca arundinacea var.genuina Schreb.) represent a wide range of genetic variation and constitute potential germplasm for tall fescue improvement. Our objective was to evaluate genome specificity of the previously-identified DNA probes and to examine the phylogenetic relationship of tall fescue with six related species by using RFLP data. A total of 29 DNA probes from aPstI-genomic library of tall fescue were hybridized toEcoRI-orHindIII-digested DNA of 32 plants from sixFestuca species and fromLolium perenne L. Fifteen probes hybridized to all seven species. The remaining 14 probes showed differential hybridization patterns (i.e., ±), especially at the diploid and tetraploid levels. This hybridization pattern reflected genome divergence in these species. The DNA probes will be useful markers in breeding programs involving interspecific and intergeneric hybridization. Cluster analyses were performed using the average genetic distances calculated with the RFLP data from 53 probe-enzyme combinations. Generally, genotypes from the same species were grouped in the same cluster. These data indicated that tall fescue has a close relationship withF. pratensis Huds. (diploid),F. arundinacea var.glaucescens Boiss. (tetraploid), andL. perenne L. (diploid) and thatFestuca pratensis andL. perenne had the closest degree of relationship.This paper is a contribution of the Missouri Agricultural Experimental Station, Journal Series no. 11,798     

Prospects for interspecific hybridization of Lupinus atlanticus Gladst. with L. cosentinii Guss.

Summary Successful crossing is reported between L. atlanticus Gladst. (2n = 38) and L. cosentinii Guss. (2n = 32), using lines of both species selected for crossability followed by selection of relatively fertile progenies. In one cross, 82E75, from a single F₂ segregating plant, 22 F₃ seeds were obtained. Some other less crossable combinations were completely sterile in the f₁ or F₂. Backcrossing to both parent species was successful, but some crosses gave relatively more seed by using F₂ plants for backcrossing rather than F₂'s. It is concluded that potential exists for introgression of useful genes in both directions.     

Polymorphism and Inheritance of Seed Storage Protein in Sunflower

The data on polymorphism and inheritance of the seed storage protein helianthinin are presented. The results of hybrid analysis indicate that in the annual sunflower Helianthus annuus, helianthinin synthesis is controlled by at least three loci: HelA, HelB, and HelC. Codominant alleles controlling different electrophoretic variants of polypeptides were identified at each of the loci. The HelA locus was inherited independently of HelB and HelC in a series of dihybrid crosses. The frequencies of recombination between loci HelB and HelC estimated in F₂ and BC of two crossing combinations were respectively 21.8 and 19.0%. Segregation of the HelC-controlled variants in the progenies from the crosses of cultured sunflower with annual wild species and forms corresponded to that theoretically expected for Mendelian inheritance. The maternal type of helianthinin inheritance was observed in the progenies from the crosses of inbred H. annuus L. lines with perennial diploid and polyploid HelianthusL. species. Altered expression of the HelClocus was detected in some hybrid combinations. These alterations appeared in early (F₁, F₂) hybrid generations and were similar in different hybrid combinations. They did not depend on the perennial paternal species being more influenced by the maternal genotype and by the mode of obtaining hybrids (in an embryo culture or in the field). These results are explained by genomic shock generated by hybridization of genetically incompatible species.     

Karyological notes on another eight species of Achillea (Asteraceae) from Turkey

The chromosome number and morphology in eight species of the sections Ptarmica (Mill.) W. D. J. Koch, Anthemoideae (DC.) Heimerl, Arthrolepis Boiss., Santolinoideae (DC.) Heimerl and Achillea of the genus Achillea L. (Asteraceae) were investigated using karyological techniques. Sample plants and seeds of A. biserrata M. Bieb., A. fraasii var. troiana Aschers. & Heimerl, A. multifida (DC.) Boiss., A. brachyphylla Boiss. & Hausskn., A. pseudaleppica Hub.-Mor., A. cretica L., A. latiloba Ledeb. ex Nordm., and A. kotschyi Boiss. subsp. kotschyi) were collected from natural habitats in 2003 and 2004. The chromosome number found in seven species was 2n = 18, while only A. kotschyi had 2n = 36. All chromosomes had median point (M), median region (m), and submedian (sm) centromers. In addition, only A. biserrata species had one subterminal (st) chromosome. An increase in asymmetry was not observed in the karyotypes of the species studied. None of the studied species had any B chromosomes.     

Experimental analyses of the evolutionary processes inTrillium

In the Japanese species ofTrillium examined here, every interspecific cross produced healthy F₁ progeny at the rate of about 50 to 60 per cent of the total inborn ovules except forT. hagae. These figures were not appreciably different from those of self-pollinated or sib-mated examples of these species.Trillium hagae, a putative natural hybrid betweenT. kamtschaticum (2n=10) andT. tschonoskii (2n=20), accepted all foreign sources of pollen grains in manual pollination. These and other crossing experiments suggest that no appreciable barrier has developed that might cause interspecific crossability and that they are habitual inbreeders. Despite theri crossability, a very low rate of actual pollen flow was detected by examining electrophoretic phenotypes of seeds taken from sympatric populations of these species.     

A new species of Lathyrus L. (section Cicercula; Fabaceae) from Turkey

A new species, Lathyrus egirdiricus H.Genc & A.Sahin (section Cicercula; Fabaceae), is described from Turkey, with illustrations and taxonomic comments. Characteristics of the species are compared with those of the related species Lathyrus hirsutus L., L. stenophyllus Boiss. & Heldr., L. sativus L., L. cassius Boiss. and L. gorgoni Parl., from which it differs mainly in the shape, length, width and venation of leaflets, length and width of the stipule, flower colour, legume and style length. © 2008 The Linnean Society of London, Botanical Journal of the Linnean Society, 2008, 158 , 301–305.     

GENOME AND KARYOTYPE RELATIONSHIPS IN THE GENUS DENDROBIUM (ORCHIDACEAE). I. CROSSABILITY

A hybridization study was made utilizing 37 species of 10 sections in 41 intra- and intersectional combinations. A total of 721 pollinations was made with 138 fruits harvested; 89 produced viable crosses. Five intrasectional and 20 intersectional combinations resulted in successful hybrids. Among the intrasectional crosses, Phalaenanthe × Phalaenanthe exhibited the highest percentage of fruits and successful crosses while Callista × Callista produced no successful crosses. Eugenanthe × Eugenanthe exhibited low crossability. Among the intersectional crosses, Ceratobium × Phalaenanthe gave the highest percentage of successful crosses, indicating a close relationship between the two groups. Also, there appears to be a fairly close relationship between Latourea and Ceratobium based on crossability. Although the sectional classification of the genus by Schlechter on the basis of vegetative and floral morphology appears to be valid, crossability studies suggest that the Ceratobium and Phalaenanthe sections might be integrated and the Eugenanthe section separated into sections or subsections.     

The in vivo anthelmintic efficacy of some Verbascum species growing in Turkey

Verbascum L. (Scrophulariaceae) species are used for desiccating wounds and as a fish poison in Anatolia as well as for diarrhea and dysentery of animals in several countries. To further evaluate their activity, methanolic extracts obtained from 13 Verbascum species growing in Turkey, including V. chionophyllum Hub.-Mor., V. cilicicum Boiss., V. dudleyanum (Hub.-Mor.) Hub.-Mor., V. lasianthum Boiss., V. latisepalum Hub.-Mor., V. mucronatum Lam., V. olympicum Boiss., V. pterocalycinum var. mutense Hub.-Mor., V. pycnostachyum Boiss. & Heldr., V. salviifolium Boiss., V. splendidum Boiss., V. stachydifolium Boiss. & Heldr. and V. uschackense (Murb.) Hub.-Mor. were evaluated for their in vivo anthelmintic activity. The extracts from V. lasianthum, V. latisepalum, V. mucronatum and V. salviifolum showed the highest inhibitory rates against Aspiculuris tetraptera at 100 mg/kg in mice. Additionally, extracts from V. dudleyanum and V. pterocalycinum var. mutense were found generally highly effective. The remaining species did not show any activity. Results of the present study support the utilization of these plant species employed in Turkish folk medicine.     

HYBRIDIZATION STUDIES WITH SPECIES OF CYNODON FROM EAST AFRICA AND MALAGASY

A collection of 198 accessions of Cynodon from East Africa and Malagasy was grown in uniform nurseries at Stillwater, Okla., and classified morphologically, studied cytologically, and tested for crossability in hybridization studies. The following taxa were recognized: C. arcuatus, C. plectostachyus, C. aethiopicus, C. nlemfuensis var. nlemfuensis, C. nlemfuensis var. robustas, C. dactylon var. aridus, C. dactylon var. coursii, and C. dactylon var. dactylon. The magnitude of barriers to gene flow was estimated by ease of hybridization and by sterility of the hybrids obtained. C. arcuatus and C. plectostachyus are well isolated from all other species in the genus. The others are sufficiently related that they may be intercrossed. The barriers to gene flow vary demonstrably in strength between different combinations of taxa. The magnitude of a barrier required to establish species limits is, perhaps, more a matter of subjective opinion than a scientific conclusion. It was concluded that no completely satisfactory classification of the genus is possible. The system adopted was a compromise between classical morphological concepts of species, the biological concept of species, and pragmatic utility.     

Relative Embryo Growth Rates in the Annual Cicer L. Species

Early embryo growth rates were studied in the nine annual speciesof Cicer L., namely, C. arietinum L., C. bijugum Rech., C. chorassanicum(Bge.) M. Pop., C. cuneatum Rich., C. echinospermum Dav., C.judaicum Boiss, C. pinnatifidum J. and S., C. reticulatum Lad.and C. yamashitae Kit. The number of embryo cells increasedexponentially with time and was log linear in all the species.Species differed in their mean cell doubling time (MCDT). Cicerechinospermum and C. yamashitae had, respectively, the longestand the shortest MCDT which ranged from 9.67 to 16.15 h forthe nine species. Failure of successful interspecific hybridizationbetween C. arietinum and the wild annual species was only partlyexplained by differences in MCDT of the parental species. Relativegenetic closeness still plays the major role in determiningsuccess of interspecific hybridization in Cicer. Chickpea, Cicer, embryo, interspecific hybridization, suspensor     

Features of Crossability, Haploidy and Polyembryony in Hybrid Combinations between Cultivated Barley Hordeum vulgare L. (2n = 14) and Wheat-Rye Substitution Lines Triticum aestivum L., Cultivar Saratovskaya 29/Secale cereale L., Cultivar Onokhoiskaya

The role of individual chromosomes of rye in the manifestation of crossability and seedling development in hybrid combinations between cultivated barley Hordeum vulgare L., cultivar Nepolegayushchii (2n = 14) and five wheat-rye substitution lines Triticum aestivum L., cultivar Saratovskaya 29/Secale cereale L., cultivar Onokhoiskaya (2n = 40 wheat + 2 rye chromosomes). Crossability, which was measured by two parameters—frequency of set grains and frequency of grains with embryos—was shown to be significantly affected by each of the five rye chromosomes examined: 1R, 2R, 3R, 5R, and 6R; the development of barley haploids was affected by rye chromosomes 1R, 3R, and 5R. We were the first to demonstrate that polyembryony could be induced by mutual effects of barley cytoplasm and rye chromosome 1R. Possible mechanisms controlling the development of haploids and twins in hybrid combinations H. vulgare × T. aestivum/S. cereale are discussed. The conclusion is drawn that hybrid combinations between cultivated barley and wheat-rye substitution lines can serve as new models for studying incompatibility mechanisms in distant crosses and genetic control of parthenogenesis.__________Translated from Genetika, Vol. 41, No. 6, 2005, pp. 784–792.Original Russian Text Copyright © 2005 by Pershina, Belova, Devyatkina, Rakovtseva, Kravtsova, Shchapova.     

Endosperm dosage relationships among Lycopersicon species

Summary Accessions of eight Lycopersicon species and five yellow-flowered Solanum species were used as males in crosses with 2x and 4x L. esculentum to observe seed set and progeny ploidy. Species which failed in crosses to L. esculentum were crossed as males to 2x and 4x L. peruvianum. In cases of low seed set, chromosome counts were undertaken to establish the nature of the progeny. Endosperm Balance Number (EBN) relationships were determined for the crossability groups. Results support the basic concept of an L. esculentum crossability complex and an L. peruvianum crossability complex. Within the L. esculentum complex, all EBNs appear identical with a value of 2. Within the L. peruvianum complex, more variability appears to exist. The EBN values of this group are higher, and may be approximately double those of the L. esculentum complex. The EBN of L. peruvianum var humifusum appears to be somewhat lower than other L. peruvianum types. The EBN values of S. lycopersicoides, S. rickii, S. ochranthum and S. juglandtfolium could not be determined experimentally. Differential aspects of Lycopersicon and tuber-bearing Solanum evolution may be interpreted on the basis of endosperm compatibility.Co-operative investigation of the Vegetable Crops Research Unit, U.S. Department of Agriculture, Agricultural Research Service, and the Wisconsin Agricultural Experiment Station     

Phylogeny of the a genomes of wild and cultivated wheat species

Diploid species of the genus Triticum L. are its most ancient representatives and have the A genome, which was more recently inherited by all polyploid species. Studies of the phylogenetic relationships among diploid and polyploid wheat species help to identify the donors of elementary genomes and to examine the species specificity of genomes. In this study, molecular analysis of the variable sequences of three nuclear genes (Acc-1, Pgk-1, and Vrn-1) was performed for wild and cultivated wheat species, including both diploids and polyploids. Based on the sequence variations found in the genes, clear differences were observed among elementary genomes, but almost no polymorphism was detected within each genome in polyploids. At the same time, the regions of the three genes proved to be rather heterogeneous in the diploid species Triticum boeoticum Boiss., T. urartu Thum. ex Gandil., and T. monococcum L., thus representing mixed populations. A genome variant identical to the A genome of polyploid species was observed only in T. urartu. Species-specific molecular markers discriminating the diploid species were not found. Analysis of the inheritance of morphological characters also failed to identify a species-specific character for the three diploid wheat species apart from the hairy leaf blade type, described previously.     

Solution structure of a synthetic peptide corresponding to a receptor binding region of FSH (hFSH-beta 33-53).

The receptor binding surface of human follicle-stimulating hormone (hFSH) is mimicked by synthetic peptides corresponding to the hFSH- chain amino acid sequences 33–53 [Santa-Coloma, T. A., Dattatreyamurty, D., and Reichert, L. E., Jr. (1990),Biochemistry 29, 1194–1200], 81–95 [Santa-Coloma, T. A., and Reichert, L. E., Jr. (1990),J. Biol. Chem. 265, 5037–5042], and the combined sequence (33–53)–(81–95) [Santa-Coloma, T. A., Crabb, J. W., and Reichert, L. E., Jr. (1991),Mol. Cell. Endocrinol. 78, 197–204]. These peptides have been shown to inhibit binding of hFSH to its receptor. Circular dichroism (CD) and nuclear magnetic resonance (NMR) spectroscopy were used to determine the structure of the first peptide in this series, the 21 amino acid peptide hFSH--(33–53), H₂N-YTRDLVYKDPARPKIQKTCTF-COOH. Analysis of CD data indicated the presence of approximately equal amounts of antiparallel -pleated sheet, turns including a -turn, other structures, and a small amount ofa-helix. The major characteristics of the structure were found to be relatively stable at acidicpH and the predominant effect of increased solvent polarity was a small increase ina-helical content. One- and two-dimensional NMR techniques were used to obtain full proton and carbon signal assignments in aqueous solution atpH 3.1. Analysis of NMR results confirmed the presence of the structural features revealed by CD analysis and provided a detailed picture of the secondary structural elements and global folding pattern in hFSH--(33–53). These features included an antiparallel -sheet (residues 38–51 and 46–48), turns within residues 41–46, and 50–52 (a -turn) and a small N-terminal helical region comprised of amino acids 34–36. One of the turns is facilitated by prolines 42 and 45. Proline-45 was constrained to thetrans conformation, whereas proline-42 favored thetrans conformer (70%) over thecis (30%). Two resonances were observed for the single alanine residue (A-43) sequentially proximal to P-42, but the rest of the structure was minimally affected by the isomerization at proline-42. The major population of molecules, containingtrans-42 andtrans-45 prolines, presented 120 NOEs. Distance geometry calculations with 140 distance constraints and energy minimization refinements were used to derive a moderately well-defined model of the peptide's structure. The hFSH--(33–53) structure has a highly polar surface composed of six cationic amino acid (arginie-35, lysine-40, arginine-44, lysine-46, glutamine-48, and lysine-49) and two anionic residues (aspartate-36 and aspartic acid-41). A hydrophobic region in the structure is composed of residues in the antiparallel -sheet and -turn which fold to produce a distorted hairpin. The structure of this domain, together with the protruding and positively charged region in the vicinity of residues 42–45, may mimic the surface of hFSH that binds to the receptor.Abreviations used: hFSH, human follicle-stimulating hormone; PB, 25 mM Na₂KPO₄, 25 mM KH₂PO₄, and 5 mM Mg Cl₂; CD, circular dichroism spectrapolarimetry; NMR, nuclear magnetic resonance spectrometry; COSY, homonuclear correlated spectroscopy; NOESY, 2D nuclear Overhauser effect spectroscopy; HOHAHA, homonuclear Hartman-Han coherence transfer; HMQCHY, reverse-detected heteronuclear multiple shift correlation, one bond; HMBC, reverse-detected heteronuclear multiple bond correlation; S/N, signal to noise ratio; TFE, trifluoroethanol.Dr. Santa-Coloma is on leave of absence from the National Research Council of Argentina (CONICET).