Chromosome numbers and ploidy levels of<Emphasis Type="Italic"> Paspalum</Emphasis> species from subtropical South America (Poaceae)

Somatic chromosome numbers of 131 accessions belonging to 55 Paspalum species from subtropical South America have been determined. All species had x = 10 as a basic chromosome number, except P. almum which had x = 6. Six ploidy levels were found among species with tetraploidy as the most frequent condition. New diploid and octoploid counts were reported. For Paspalum lilloi and P. glabrinode (both 2n = 2x = 20), and for P. ellipticum, P. erianthoides, P. ovale and P. remotum (all 2n = 8x = 80) sporophytic chromosome numbers are presented for the first time. Records that differ from previously reported counts are given for the following species: P. paucifolium (2n = 2x = 20), P. ceresia (2n = 6x = 60), P. conjugatum (2n = 6x = 60), P. alcalinum (2n = 6x = 60) and P. aff. arundinellum (2n + 1 = 5x + 1 = 51). These chromosome data are discussed in light of ploidy-level variation and implications for breeding systems within and among species.     

Karyotypic studies in wild germplasm of <Emphasis Type="Italic">Arachis</Emphasis> (Leguminosae)

The karyomorphology for eight diploid species of Arachis belonging to three sections has been described for the first time, Sect. Extranervosae: A. macedoi (2n = 20m) and A. retusa (2n = 14m + 6sm); Sect. Heteranthae: A. sylvestris (2n = 16m + 4sm); Sect. Procumbentes: A. chiquitana (2n = 18m + 2sm); Sect. Arachis: A. cruziana (2n = 18m + 2sm), A. herzogii (2n = 18m + 2sm), A. simpsonii (2n = 20m) and A. williamsii (2n = 20m). A pair of satellited chromosomes was observed in all species. A chromosomes were found in A. chiquitana, A. herzogii and A. simpsonii. Karyotypic differences between sections were observed, but not enough to establish a characteristic karyotype pattern for each section. However, the species may be differentiated by the presence of A chromosomes, the type and position of satellites, and the karyotype formulae. These results are discussed with regard to karyotype evolution in Arachis to contribute to understanding the role of chromosome changes in the evolution of the genus.     

Collection and evaluation of the genus <Emphasis Type="Italic">Lilium</Emphasis> resources in Northeast China

Northeast China is known as an important distribution region of the genus Lilium, with ten native species reported among the 55 species found in the whole country so far. This paper is about the distribution, collection, classification and evaluation of the Lilium germplasm collected from this area. The accessions were identified and classified into six species and three variants, including Lilium lancifolium Thunb., L. pumilum DC., L. dauricum Ker-Gawl, L. cernuum Komar., L. amabile Palib., L. distichum Nakai, L. concolor Salisb. var. buschianum (Lodd.) Baker, L. concolor Salisb. var. megalanthum Wang et Tang, and L. leichtlinii Hook. f. var. maximowiczii (Regel) Baker. Nevertheless, the species L. callosum Sieb. has not been collected by now. Chromosome counts showed that L. lancifolium was triploid (2n = 3x = 36) and the other species were diploid (2n = 2x = 24). Besides L. distichum, chromosome number variations were observed in the root-tip cells among the other eight species. Haploid cells (2n = x = 12) were discovered in L. lancifolium. B-chromosomes were observed in L. lancifolium, L. dauricum, L. pumilum, L. concolor var. buschianum and L. concolor var. megalanthum. The analytic hierarchy process was employed to evaluate ornamental characteristics and potential utilization of nine identified species. It seemed that L. lancifolium, L. cernuum, L. pumilum and L. concolor var. buschianum had better ornamental value and utilization potential than others.     

Diversity analysis of <Emphasis Type="Italic">Acacia tortilis</Emphasis> (Forsk.) Hayne ssp. <Emphasis Type="Italic">raddiana</Emphasis> (Savi) Brenan (Mimosaceae) using phenotypic traits,chromosome counting and DNA content approaches

Acacia tortilis (Forsk.) Hayne ssp. raddiana (Savi) Brenan (Family Fabaceae; subfamily Mimosoideae) is a pioneer tree of dry areas. In spite of its several uses, there are no any published studies which deal with genetic diversity of Acacia tortilis (Forsk.) Hayne ssp. raddiana (Savi) Brenan in Tunisia. For this reason, here we study its genetic diversity with morphometric (only in Tunisian populations), chromosome counting, and cytometric (in Tunisian and Ziambabwean populations) approaches. Morphological field studies of four Tunisian populations (Bouhedma, Haddej, Hajeb and Gtar, respectively, designated as A, B, C, D) of A. tortilis (Forsk.) Hayne ssp. raddiana (Savi) Brenan using a general linear model (ANOVA) revealed statistically highly-significant differences between populations for all examined characters (P < 0.0001). Significant differences were found also between genotypes for the majority of morphological traits (P < 0.0001) except the width of 10 pods (laP), weight of 10 pods (Wt) and seed number of 10 pods (Sn) (P ≥ 0.110). The variability in the tree, pod and seed characters can be exploited for agro-industrial purposes. The DNA amount and chromosome numbers of populations Umguza and Gwaii River from Ziambabwe and of Tunisian populations A, B, C and D were determined. Tunisian populations had 2C nuclear DNA contents of 2.95–3.03 pg, and were shown to be tetraploid (2n = 4x = 52), whilst the two Ziambabwean populations had 1.39–1.40 pg and were diploid (2n = 2x = 26). It is suggested that the Tunisian populations are paleotetraploids, adapted to the more-arid local conditions.     

Karyotype and genetic relationship based on RAPD markers of six wild buckwheat species (<Emphasis Type="Italic">Fagopyrum</Emphasis> spp.) from southwest of China

Karyotypes of six wild buckwheat species from Sichuan Pan’xi Regions of China were investigated in present study. This study will help in understanding evolutionary mechanisms and relationships among the taxes in this section. The karyotypes of three species, F. densovillosum, F. gracilipes var. odontopterum and F. gracilipes are being reported for the first time. F. esculentum, F. cymosum, F. tataricum and F. densovillosum are diploid while F. gracilipes var. odontopterum and F. gracilipes are tetraploid, 2n = 4x = 32. At diploid level, the variation of the buckwheat chromosome karyotypes is bigger; however, on the tetraploid level, it shows a higher similarity. The karyotype evolutionary trend of buckwheat indicated that F. densovillosum seemed to be more advanced than F. gracilipes var. odontopterum and F. gracilipes. F. densovillosum, F. gracilipes var. odontopterum. and F. gracilipes were found more closely related genetically whereas F. tataricum clustered into a separate group. F. esculentum and F. cymosum clustered together in one separate group.     

Karyotype characterization reveals an up and down of 45S and 5S rDNA sites in <Emphasis Type="Italic">Crotalaria</Emphasis> (Leguminosae-Papilionoideae) species of the section Hedriocarpae subsection Macrostachyae

The genus Crotalaria is one of the largest within the family Leguminosae-Papilionoideae, with more than 600 species. However, few karyotypes have been described. In the present paper, five species belonging to the section Hedriocarpae were studied (subsection Machrostachyae), in order to better understand chromosomal evolution in Crotalaria. The results reveals that all species presented 2n = 2x = 16 with symmetrical karyotypes, and slight differences in the chromosome morphology. A secondary constriction was identified at short arm of the pair 1. The 45S rDNA was mapped in the secondary constriction and adjacent heterochromatin (NOR-heterochromatin) and a minor site was identified in C. ochroleuca. The 5S rDNA was mapped linked to 45S rDNA at chromosome 1 short arm in all species. Additional sites for 5S rDNA were identified in C. pallida, C. striata and C. mucronata. Heterochromatin blocks around the centromeres are not CMA⁺ neither DAPI⁺. The karyotypes of the subsection Macrostachyae are characterized by an inversion at chromosome pair one in relation to previous specialized floral species analyzed. Additional sites of 45S and 5S rDNA were assumed to be a result of transposition events by different ways. The results suggest heterochromatin differentiation and the position of ribosomal genes indicates chromosomal rearrangements during evolution. Karyotype characteristics corroborate the morphological infrageneric classification.     

Seed dimorphism,chromosome number and karyotype of the amphicarpic species <Emphasis Type="Italic">Trifolium argentinense</Emphasis> Speg.

Amphicarpy, a specialized form of dimorphism where fruits and seeds are formed in underground and aerial flowers, has been reported in only ca. 50 flowering plants. Trifolium argentinense Speg. is an amphicarpic legume species that occurs in native pastures of Southern Brazil. Data on seed dimorphism, chromosome number and karyotype of the species are presented for the first time. T. argentinense is diploid, with 2n = 2x = 16. Chromosome size range from ca. 2.8 to 1.6 μm, the karyotypic formula is 3 metacentric + 1 satellite-bearing metacentric + 3 acrocentric + 1 subacrocentric and a TCL (total complement length) of 18.10 μm. All the subterranean, but around 70% of the aerial legumes formed seeds. Subterranean seeds were larger and heavier (2.1 mm and 0.0029 g, respectively) than the aerial ones (1.8 mm and 0.0016 g, respectively). As a follow up to this work, we plan to characterize aerial and subterranean-seed-derived plants regarding aspects such as growing rate, height, leaf size and forage production, as well as to determine the exact mode of reproduction of T. argentinense by pollination experiments and the use of molecular markers.     

Karyotypic studies on <Emphasis Type="Italic">Campanumoea</Emphasis> (Campanulaceae)—endemic to China

Radix Campanumoeae (C. javanica Bl.) has been used in Miao herbal medicine to treat neurasthenia and consumptive disease for hundreds of years. Though Radix Campanumoeae shows great potential for utilization in medical studies, this herb crop has not been cultivated industrially in China. Many species in the Campanumoea genus are similar in phenotype; therefore, a karyotypic study would prove useful for clearly distinguishing Radix Campanumoeae from related species within the same genus, for germplasm preservation and for breeding Radix Campanumoeae. 10 accessions of four species in this genus and 5 accessions in 5 relative genera from SCSB were used for karyotype determination. The results showed a karyotype of 2n = 16 = 2m + 12sm + 1st in Campanumoea, and a karyotype of 2n = 18 = 6 m + 12sm in Cyclocodon. Based on the chromosome number and the karyotypic formula, we suggest that the Campanumoea genus can be divided into two genera, which is in agreement with results observed from pollen morphology and from homological usage in Chinese herbal medicine. The chromosome length in C. javanica subsp. javanica and C. javanica subsp. japonica Makino, ranged from 2.24 to 1.38 μm and 2.04 to 1.31 μm, respectively; and their haploid sets were almost identical (13.15 and 13.16 μm, respectively). This indicates that chromosomal rearrangements occur within chromosomes IV, V and VII without a net gain or loss of genetic material.     

Cloning and characterization of novel low molecular weight glutenin subunit genes from two <Emphasis Type="Italic">Aegilops</Emphasis> species with the C and D genomes

Four novel low molecular weight glutenin subunit genes (designated as AmLMWm1, AcLMWm1, AcLMWm2 and AcLMWm3) were isolated and characterized from the genomic DNA of two Aegilops accessions, AmLMWm1 from Aegilops markgrafii (Greuter) K.Hammer (2n = 2x = 14, CC), AcLMWm1, AcLMWm2 and AcLMWm3 from Aegilops cylindrica Host (2n = 4x = 14, CCDD). The coding regions of AmLMWm1, AcLMWm1, AcLMWm2 and AcLMWm3 were 1,092, 1,119, 912 and 936 bp in length, encoding 39,168, 40,297, 31,961 and 33,396 Da LMW-GS, respectively. In order to confirm their authenticity, these LMW-GS genes were successfully expressed in E.coli. The four novel genes belong to LMW-m types and, according to the first and seventh cysteine positions, were further classified as types III, I, IV and V, respectively. Among these novel genes, AmLMWm1 and AcLMWm1 possessed a longer repetitive domain (20 and 22 repeats) than common LMW-GS genes, which was considered to be associated with good dough quality of wheat. Phylogenetic analysis showed C and D genomes of Aegilops involved in this study had LMW-GS loci similar to those of the A, B, and D genomes in common wheat.     

Variation for stomatal characteristics and water use efficiency among diploid,tetraploid and hexaploid Iranian wheat landraces

Wheat is one of the most important crops in the world. Its study has involved anatomy, ecology, physiology, molecular biology, biotechnology, and cultivation. Knowledge of the relationship of diploid, tetraploid and hexaploid wheat with stomatal characteristics and water-use efficiency is spare and is subject to argument. The present study was aimed to examine different characteristics of stomata in 28 Iranian landraces belonging to the species Triticum monococcum (2n = 2x = 14), Triticum durum (2n = 4x = 28) and Triticum aestivum (2n = 6x = 42), respectively and investigated a possible relationship between these characteristics and water use efficiency by pot cultivation experiments. The results revealed large variation among landraces as well as between the different species for stomatal frequency and size. The diploid wheat species had the highest stomatal frequency and the lowest stomatal length and width. The hexaploid species had a lower stomatal frequency than the tetraploid species. A highly significant relationship was noted between the value of those traits on the adaxial and abaxial surfaces of the leaf. The ratio of adaxial to abaxial values appeared to be constant for a given species. Both stomatal frequency and size were associated with ploidy level, but also with the nature of the constituting genomes of the species. A highly significant negative association was found among accessions between stomatal frequency and size. As a consequence, the variation for stomatal area per unit leaf area was less than for the other traits. Diploid and hexaploid wheat have significantly higher water use efficiency, compared to tetraploid wheat. No clear association was found, however, between water use efficiency and stomatal characteristics.     

Recombination around the <Emphasis Type="Italic">P</Emphasis> locus for long glume phenotype in experimental introgression lines of <Emphasis Type="Italic">Triticum aestivum</Emphasis> – <Emphasis Type="Italic">Triticum polonicum</Emphasis>

A set of experimental introgression lines of Triticum aestivum L. cv. Novosibirskaya 67 (N67)—Triticum polonicum L. line IC 12196 was developed using a small-scale bulk breeding method. The linkage map in chromosome 7A was constructed using F₂ hybrids of N67/IC12196 and 34 microsatellite markers. The P gene was flanked by the centromeric markers, Xgwm890 (18.6 cM) and Xbarc108 (20.0 cM) on the long arm of chromosome 7A. Among 124 introgression lines, 118 lines were hexaploid (2n = 6x = 42), and 6 were tetraploid (2n = 4x = 28). Among hexaploid accessions, 68 were long-glumed, whereas 50 were normal-glumed. Thirty-four polymorphic microsatellite markers were scored for either the N67 alleles or IC 12196 alleles in 124 introgression lines derived from N67/IC 12196. The UPGMA dendrogram showed five clusters; Cluster 1 mainly contained hexaploid introgression lines with long glumes. Although the alleles around the P locus were recombined with IC1296 alleles, the distal end of the chromosome contained N67 alleles. Cluster 2 mainly contained normal glumed, hexaploid introgression lines. These predominantly had the N67 alleles on the long arm of chromosome 7A and the short arm proximal to the centromere. Cluster 3 contained long-glumed, hexaploid wheat lines with relatively high level of recombination. Cluster 4 contained non-parental alleles. Cluster 5 contained the group of tetraploid wheat lines. These tetraploid lines have IC12196 alleles on both arms of chromosome 7A. The frequency spectrum of parental alleles and chromosomal blocks among introgression lines suggested that T. aestivum – T. polonicum hybridization can rapidly give rise to a new landrace due to selective introgression of the P gene.     

Karyotypic variation in <Emphasis Type="Italic">Nicotiana</Emphasis> section Suaveolentes

Nicotiana section Suaveolentes (Solanaceae) currently includes 28 species and subspecies that are endemic to Australasia and the South Pacific and one African species, N. africana. The section is monophyletic and of allotetraploid origin, but relationships among the species in it and its diploid progenitors are poorly understood. Here we report chromosome numbers for 20 of the 29 taxa from the Suaveolentes, including a count for one recently proposed species for which no number has previously been available. Many of the published chromosome numbers for the Suaveolentes are confirmed in this study. However, six counts were different from the published numbers including n = 15 for N. maritima and N. suaveolens, which is a new chromosome number for the genus. Nicotiana goodspeedii and N. rotundifolia were n = 16, and the same number was found in the suggested species N. sp. ‘Corunna’. Nicotiana suaveolens contains polyploid races of n = 32 and here we report the probable existence of an n = 31 race as well. Karyotypic variation within species and within the section is apparently much greater than previously thought and further investigation is warranted.     

Development and identification of a wheat-<Emphasis Type="Italic">Psathyrostachys huashanica</Emphasis> addition line carrying HMW-GS,LMW-GS and gliadin genes

Psathyrostachys huashanica Keng, in the family Poaceae, subtribe Triticeae is an endangered and endemic species of China. It is characterized as Shaanxi, drought tolerant and fungus and disease resistant. In this paper, a wheat (Triticum aestivum L.)—P. huashanica disomic addition line “H9021-28-5” was developed using cytogenetics methods including SDS–PAGE, A-PAGE, and GISH. These investigations revealed that the chromosome number and configuration of “H9021-28-5” were 2n = 44 = 22 II. The mitotic and meiotic GISH analysis indicated that “H9021-28-5” contained 42 wheat chromosomes and a pair of P. huashanica chromosomes. The SDS–PAGE and A-PAGE analysis showed that “H9021-28-5” carried the HMW-GS, LMW-GS and gliadin genes of P. huashanica. The results suggest that these storage protein genes of P. huashanica had been transferred into common wheat. Development of this new germplasm is significant for enriching and improving wheat resources of storage proteins genes, and for continuing to exploit the advantageous genes of P. huashanica.     

CMA staining analysis of chromosomes in several species of Aurantioideae

Fluorochrome staining with chromomycin A₃ (CMA) was used to characterize and compare the CMA banding patterns of chromosomes of 17 species from 13 genera of Aurantioideae, which is one of the seven subfamilies of Rutaceae. All species used in this study had 2n = 18 chromosomes. These chromosomes were classified into five types based on the number and position of CMA-positive bands; B: one telomeric and one proximal band, C: two telomeric bands, D: one telomeric band, E: without bands and Dst: type D with a satellite chromosome. Each species possessed two or four types of chromosomes and unique CMA banding patterns. The CMA banding patterns were 6D + 12E in Clausena anisata (Willd.) Hook. f.,1C + 3D + 14E in Murraya koenigii (L.) Spreng., 1C + 11D + 6E in Murraya paniculata (L.) Jack, 1B + 1C + 10D + 6E in Merrillia caloxylon (Ridl.) Swing., 1C + 9D + 7E + 1Dst in Paramignya lobata Burkill, 2C + 5D + 11E in Severinia buxifolia (Poir.) Tenore, 5D + 13E in Hesperethusa crenulata (Roxb.) Roem., 16D + 2E in Citropsis gabunensis (Engl.) Swing. et M. Kell, 14D + 4E in Citropsis schweinfurthii (Engl.) Swing. et M. Kell, 8D + 10E in Atalantia monophylla DC., 1C + 3D + 14E in Atalantia ceylanica (Arn.) Oliv., 2D + 16E in Atalantia roxburghiana Hook. f., 18E in Swinglea glutinosa (Blanco) Merr., 2D + 16E in Aegle marmelos (L.) Corr., 4D + 14E in Afraegle paniculata (Schum.) Engl., 2B + 2D + 13E + 2Dst in Feronia limonia (L.) Swing. and 3B + 9D + 6E in Feroniella oblata Swing. The advanced genera in each tribe and subtribe such as Merrillia and Feroniella showed heterochromatin (CMA-positive bands) rich chromosome configuration in general. Swinglea glutinosa without heterochromatin rich chromosome, which is considered to be the most primitive chromosome configuration, seems to be the key genus for clarifying the evolution of the tribe Citreae.     

Cytological and genetic mapping of the gene for four-awned phenotype in <Emphasis Type="Italic">Triticum carthlicum</Emphasis> Nevski

A striking feature of Triticum carthlicum Nevski (2n = 4x = 28, AABB genome) is an awn-like appendage on the glume, so all the spikelets appear four-awned. From the word “tetraaristatus” (four-awned), the locus was named “t” to distinguish it from the b ₁ locus on chromosome 5A and b2 locus on chromosome 6B for awn formation. The aims of present study was to determine the chromosomal location of the t locus in tetraploid wheat T. carthlicum, and (2) to assess linkage relationships of t, Rht12 using microsatellite markers in T. carthlicum. Combined cytological evidence and microsatellite mapping showed that t was located on the chromosome 5AL. The alignment of the gene was Xgwm291–(6.4 cM)–t–(6.7 cM)–Xgwm410 in F₂ of T. carthlicum #521/LD222, and Xhbg219–(12.4 cM)–t–(5.1 cM)–Xgwm410–(6.2 cM) –Rht12 in F₂ of ANW 16C/#521 on the 5AL. The t locus was different from b1 locus, because it was known that the semi-dwarf Rht12 gene was completely linked with b1 gene. We discussed that the four-awned phenotype of T. carthlicum was introduced from Triticum aestivum L. ssp. carthlicoides.     

Production and cytogenetics of trigeneric hybrid involving <Emphasis Type="Italic">Triticum</Emphasis>, <Emphasis Type="Italic">Psathyrostachys</Emphasis> and <Emphasis Type="Italic">Secale</Emphasis>

Trigeneric hybrids may help establish evolutionary relationships among different genomes present in the same cellular-genetic background, and also offers the possibility to transfer different alien characters into cultivated wheat. In this study, a new trigeneric hybrid involving species from the Triticum, Psathyrostachys and Secale was synthesized by crossing wheat-P. huashanica amphiploid (PHW-SA) with wheat-S. cereale amphiploid (Zhongsi 828). The crossability of F₁ hybrid was high with 35.13%, and the fertility was 41.95%. The morphological characteristics of F₁ plants resembled the parent Zhongsi 828. The trigeneric hybrids pollen mother cells (PMCs) regularly revealed averagely 19.88 univalents, 9.63 ring bivalents, 3.97 rod bivalents, 0.60 trivalents and 0.03 tetravalents per cell. Multivalents consisted of trivalents and tetravalents can be observed in 52.7% of cells. A variation of abnormal lagging chromosome, micronuclei and chromosome bridge were formed at anaphase I and telophase II. The mean chromosomes number of F₂ progenies was 2n = 46.13, and the distribution range was 42–53. GISH results revealed that most F₂ plants had 6–12 S. cereale chromosomes, and only 0–2 P. huashanica chromosomes were detected. The results indicated that S. cereale chromosomes can be preferentially transmitted in the F₂ progenies of trigeneric hybrid than P. huashanica chromosomes. A survey of disease resistances revealed that the stripe rust resistance from the PHW-SA were completely expressed in the F₁ and some F₂ plants. The trigeneric hybrid could be a useful bridge for the transference of P. huashanica and S. cereale chromatins to common wheat.     

Geographical distribution of wild <Emphasis Type="Italic">Daucus</Emphasis> species in the natural grasslands of the Argentinian pampas

Three wild carrot species have been reported in the argentinian flora: Daucus montanus Humb. et Bonpl. ex Schult., D. montevidensis Link ex Sprengel and D. pusillus Michx. There is a discrepancy among authors about the distinctive morphological traits of the last two species; thus, it is difficult to ascertain if they are truly two distinct taxa. Based on the available literature and in the search of a paradigmatic site, four collection trips were carried out in 2004 and 2005 in Buenos Aires and Southern Entre Ríos provinces. Populations were sampled at 30 sites, and local environmental parameters and associated plant species were recorded. Morphological observations and chromosome counts were carried out on 10 plants/population. Three morphological phenotypes were distinguished: one in 18 populations, all with 2n = 2x = 18, and two in the remaining 12, with 2n = 2x = 22 or aneusomaty (2n = 2x = 20, 22). Populations of the first phenotype were assigned to wild D. carota and the rest, tentatively, to D. pusillus (D. montevidensis?), till further evaluations are carried out in test sites to verify this tentative conclusion.     

Karyotype Variation within Some Natural Populations of Sulla (Hedysarum coronarium L., Fabaceae) in Algeria

As a part of the characterization and the valorization of plant genetic resources of fodder and pastoral interest in Algeria, a cytogenetic study was undertaken for nine natural populations of Hedysarum coronarium L. originating from North-East Algeria. The chromosomic characterization was realized throughout the mitosis, the C-banding and the meiosis analysis. Ecological factors (altitude and rainfall) of the originating environment of the different populations were considered in this study. Six Algerian populations present the stable chromosome number, usually observed in this species (2n = 16), whereas three others present two numbers. The first number (2n = 2x = 16), previously cited by other authors throughout the world, and the second one (2n = 2x = 18) is newly observed within Hedysarum coronarium L. Both mitotis ans meiosis confirmed these numbers. The chromosomes are median and the karyotype is primitive in terms of form and size. The C-banding method showed off three types of bands (telomeric, intercalary, centromeric). The originating environment seems to have an effect on the existing variability in Hedysarum coronarium L.     

Inheritance of the branching in hybrid populations among tetraploid wheat species and the new branched spike line 166-Schakheli

The new branched spike form of wheat was synthesized from a cross between a complex wheat line 171ACS {[(T. durum Desf. × Ae. tauschii Coss.) × S. cereale L. ssp. segetale Zhuk.] × T. aestivum L. ‘Chinese Spring’} (2n = 6x = 42, AABBDD) and durum wheat variety T. durum Desf. ‘Bereketli-95’ (2n = 4x = 28, AABB). This branched spike form is distinguished significantly from the other branched spike forms known so far. Later on basis of these plants have been developed the branched spike lines. This study was aimed to generate the segregating populations from reciprocal (F₁–F₃) and backcross (BC₁F₁–BC₁F₃) crosses between one of such lines—166-Schakheli (2n = 4x = 28, AABB) and tetraploid wheat species (T. polonicum L., T. turanicum Jakubz., T. durum Desf.) for revealing the inheritance character of this branching trait and study meiotic behavior in reciprocal (F₁, F₂) and backcross (BC₁F₁) progenies. Results showed that this trait is controlled by a single recessive gene despite certain irregularity against Mendelian law in F2 generations and does not depend on gene dosage, i.e., number of chromosomes.     

New data and phylogenetic placement of the enigmatic Old World lupin: <Emphasis Type="Italic">Lupinus mariae</Emphasis>-<Emphasis Type="Italic">josephi</Emphasis> H. Pascual

Lupinus mariae-josephi H. Pascual is an intriguing lupin species recently discovered in the Mediterranean region. New data from seed coat micromorphology, cytology, and DNA sequences were generated in order to extend our knowledge on this species and to examine its evolutionary relationships within Lupinus. This species shows morphological similarities with the Mediterranean smooth seeded species of sections Micranthi and Lutei. It shares the same chromosome number 2n = 52 with the latter Old World taxa, but also with unifoliolate lupins from Florida. Besides, L. mariae-josephi exhibited a seed coat micromorphology “intermediate” between the rough and the smooth seed coat types. Phylogenetic analyses using ITS and ETS nrDNA spacers, and the LEGCYC1A locus supported L. mariae-josephi as a distinct Old World line, placed out of the Scabrispermae, but without clear placement amongst the Mediterranean smooth-seeded lineages. Unexpectedly, LEGCYC1A data revealed phylogenetic affinities between L. mariae-josephi and L. villosus, a unifoliolate North American lupin that might have experienced a reticulated evolutionary process. All together, the data underline the phylogenetic interest of L. mariae-josephi in Lupinus and the need of additional investigations in order to definitely elucidate its enigmatic status. Moreover, as L. mariae-josephi is one of the rare Old World lupins strictly restricted to poor basic soils, it opens new perspectives of ecological and agronomic interests in the wide areas of poor calcareous soils in the Mediterranean region.