Taxonomic and evolutionary relationships in the genus Vella L. (Cruciferae)

Thirty-two differential characters are numerically analysed for the six existing taxa of the genus Vella L. The closely related monotypic genus Boleum Desv. is also included for comparison. Most of the characters used are morphological, but cariological, ecological and biogeographical aspects have also been studied. The results indicate that four distinct species, one ( V. pseudocytisus L.) with three sub-species, should be distinguished. The new combination V. anremerica (Lit. et Maire) Gómez-Campo (basionym: V. pseudocytisus L. subsp. anremerica Lit. et Maire) and the new name V. pseudocytisus L. subsp. paui Gómez-Campo for V. pseudocytisus L. var. glabrescens Willk., nornen nudum are presented. A key is given to aid identification of these taxa. Their conservation status is also discussed.     

The phylogenetic significance of flavonoids in Crambe L. (Cruciferae)

A total of 21 flavonoid compounds has been detected in 14 species of Crambe. In general, both the sections of the genus and the species can be distinguished easily by their flavonoid patterns. The members of Crambe sections Crambe and Dendrocrambe seem to be the most primitive with their perennial or rhizocarpous habit. They show a diversity of flavonol glycosides, derived from either kaempferol or quercetin. The presumed presence of proanthocyanidins confers an additional primitive character to Crambe section Dendrocrambe. In contrast, members of Crambe section Leptocrambe show a relatively poor pattern where the quercetin glycosides have disappeared. In the case of C. hispanica and C. abyssinica flavonols are completely absent while two flavones, luteolin and apigenin appear in glycosidic form; these are probably the most evolved Crambe species and exhibit an annual habit. A dendrogram exclusively based on data of the presence or absence of flavonoids has been constructed. It is similar to the one that could have been expected from use of morphological data alone, but it does provide some hints on the possible phylogenetic relationships between the species. Flavonoid evidence also supports the hypothesis on an east-west Mediterranean disjunction within the genus.     

Cyanus triumfettii subsp. triumfettii (Compositae) does not occur in the western Carpathians and adjacent parts of Pannonia: karyological and morphological evidence

The pronounced morphological variation of the Cyanus triumfettii group (syn. Centaurea triumfettii s. latissimo) in the western Carpathians and Pannonia has resulted in confusing and contradictory taxonomic treatments. We focus on the taxonomic identity of populations which have been treated as C. triumfettii subsp. triumfettii in this area. Karyological and morphological data were used to compare 47 populations (746 plants) from the western Carpatho–Pannonian area with 8 populations (105 plants) from the type locality of C. triumfettii subsp. triumfettii and its vicinity in the southern part of the western Alps. Chromosome counting and flow cytometry confirmed the diploid level for all analysed populations. Multivariate morphometric analyses revealed a clear separation between Alpine populations and populations in the western Carpathians and Pannonia. The results proved that C. triumfettii subsp. triumfettii does not occur in the western Carpathians and Pannonia. Instead, populations in this area are provisionally treated as C. triumfetti subsp. axillaris , C. triumfettii subsp. dominii and C. triumfettii subsp. strictus . The complex morphological variation of these subspecies is discussed and the need for further taxonomic studies is emphasized.     

Taxonomy and distribution of Poa carpatica in the Western Carpathians

We examined the taxonomic status and distribution of Poa populations from supramontane and subalpine belt of the central Western Carpathians, so far classified as P. nemoralis subsp. carpatica and P. nemoralis subsp. montana. Significant morphological differences from P. nemoralis s. str. as well as combination of shared vs distinct characters allow us to attribute the populations under study to the species P. carpatica (V. Jirásek) Chopyk with two subspecies: P. carpatica subsp. carpatica a P. carpatica subsp. supramontana subsp. nova.     

Melliferous potential of Brassica napus L. subsp. napus (Cruciferae)

Morphophysiological characteristics of oilseed rape flowers, such as features of the nectaries, nectar production, and observations on honey bee visits and honey and seed yield were studied with the aim to evaluate the melliferous potential of this crop as well as its attractiveness to pollinators. Calculation of the theoretical maximal honey yield revealed that the actual amount of extracted honey was much lower than the potential yield, indicating that this bee pasture is underutilized. We found that honey bee pollination increased oilseed rape yield, i.e., seed production, by 12 % compared with the treatment in which pollinators were excluded.     

Myrosinase in Brassicaceae (Cruciferae): III. EFFECT OF ASCORBIC ACID ON MYROSINASES FROM SINAPIS ALBA L. SEEDLINGS

The effect of L-ascorbic acid (AA) on myrosinase activity wasstudied in white mustard, Sinapis alba L. Enzyme extracts wereprepared from different organs of dark- and light-grown seedlings.The highest activation caused by AA was found for myrosinasefrom light-grown primary roots. The activation level was morethan 12 times higher than that of the control. The maximum activationgenerally occurred at 1–10 mM AA, and in the case of myrosinasefrom light-grown hypocotyls even at 50 mM AA. The myrosinasesfrom cotyledons were least affected by addition of AA. To studythe effect of AA on different isoenzymes of myrosinases, theisoenzymes were separated on polyacrylamide gels. When the gelswere incubated in an AA solution, after electrophoresis differenceswere found in the activation of isoenzymes of different myrosinases.     

Tetra-acylated cyanidin 3-sophoroside-5-glucosides from the flowers of Iberis umbellata L. (Cruciferae)

The structures of 11 acylated cyanidin 3-sophoroside-5-glucosides (pigments 1-11), isolated from the flowers of Iberis umbellata cultivars (Cruciferae), were elucidated by chemical and spectroscopic methods. Pigments 1-11 were acylated with malonic acid, p-coumaric acid, ferulic acid, sinapic acid and/or glucosylhydroxycinnamic acids.Pigments 1-11 were classified into four groups by the substitution patterns of the linear acylated residues at the 3-position of the cyanidin. In the first group, pigments 1-3 were determined to be cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the acyl moiety varied with none for pigment 1, ferulic acid for pigment 2 and sinapic acid for pigment 3. In the second one, pigments 4-6 were cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(4-O-(β-glucopyranosyl)-trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the acyl moiety varied with none for pigment 4, ferulic acid for pigment 5 and sinapic acid for pigment 6. In the third one, pigments 7-9 were cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(4-O-(6-O-(trans-feruloyl)-β-glucopyranosyl)-trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which the acyl moiety varied with none for pigment 7, ferulic acid for pigment 8, and sinapic acid for pigment 9. In the last one, pigments 10 and 11 were cyanidin 3-O-[2-O-(2-O-(acyl)-β-glucopyranosyl)-6-O-(4-O-(6-O-(4-O-(β-glucopyranosyl)-trans-feruloyl)-β-glucopyranosyl)-trans-p-coumaroyl)-β-glucopyranoside]-5-O-[6-O-(malonyl)-β-glucopyranoside], in which acyl moieties were none for pigment 10 and ferulic acid for pigment 11.The distribution of these pigments was examined in the flowers of four cultivars of I. umbellata by HPLC analysis. Pigment 1 acylated with one molecule of p-coumaric acid was dominantly observed in purple-violet cultivars. On the other hand, pigments (9 and 11) acylated with three molecules of hydroxycinnamic acids were observed in lilac (purple-violet) cultivars as major anthocyanins. The bluing effect and stability on these anthocyanin colors were discussed in relation to the molecular number of hydroxycinnamic acids in these anthocyanin molecules.     

Cytogenetic studies in Cochlearia L. (Cruciferae). The chromosomal constitution of C. danica L.

Genome analysis has been used to investigate the relationship of C. danica L. to the diploid and tetraploid species in the genus. The results of this analysis suggest that C. danica has the genomic constitution A¹ ₇ A¹ ₇ A² ₇ A² ₇ T₇ T₇. Both A₇ genomes in C. danica are segmentally differentiated from the A₇ genome in C. groenlandica L. and from the similar A₆ genomes in C. pyrenaica DC. and C. officinalis L. but, in hybrids, are capable of some pairing with these genomes. A² ₇ is more distantly related to A₇ and A₆ than is A¹ ₇ and in A₇ some of the differentiation has taken place by reciprocal translocations. A¹ ₇ and A² ₇ still retain enough homology for pairing between them. The T₇ genome has no homology with any of the A genomes but may be derived from an ancestral T₆ genome.     

Studies in the genus Physaria (Cruciferae)

Building upon a taxonomic treatment ofPhysaria published in 1939, an extension of information concerning the genus is presented. Comments on misapplication of the nameP. acutifolia Rydb., a new trichome type forPhysaria, and a high elevation species in Colorado are accompanied by the presentation of four new taxa. These areP. alpina, P. eburniflora, P. lepidota, andP. newberryi var.racemosa.     

Hypersensitivity reaction of Brassica nigra L. (Cruciferae) kills eggs of Pieris butterflies (Lepidoptera: Pieridae)

Summary Some individual plants of the mustard Brassica nigra in lowland California kill eggs of the Crucifer-specialist herbivores Pieris rapae and P. napi by producing a necrotic zone at the base of the egg, thereby apparently desicating it. This is a typical hypersensitivity reaction, but to an atypical stimulus. The eggs can be rescued by maintaining them in a saturated atmosphere. Attempts to demonstrate a bacterial or fungal agent associated with the reaction were unsuccessful.     

Myrosinase in Brassicaceae (Cruciferae): II. MYROSINASE ACTIVITY IN DIFFERENT ORGANS OF SINAPIS ALBA L.

Seeds of Sinapis alba L. were germinated in darkness for 3 dand a part of the etiolated seedlings were transferred to long-dayconditions for 6 weeks. Myrosinase solutions were prepared forcotyledons, hypocotyls, primary roots, leaves, stems, inflorescences,and seeds, and used to hydrolyse sinigrin. Glucose, one of the cleavage products, was determined by fourdifferent spectrophotometric methods, and their usefulness forcalculations of myrosinase activity in crude plant extractsis considered. Specific activity was calculated in relations to protein, andit was found to be about 30% higher in seedlings and also higherin seeds than in adult plants. Of the organs, those with thehighest activity were the hypocotyls and the stems. The differentparts of the plant contained different numbers of isoenzymes,as shown by polyacrylamide gel electrophoresis. Seedlings yieldedtwo, and adult plants four or five isoenzymes.     

Cytogenetic studies in Cochlearia L. (Cruciferae). The origins of C. officinalis L. and C. micacea Marshall

Genome analysis has been used to investigate the evolutionary relationships of the tetraploid species in the genus Cochlearia. The results indicate that both C. officinalis L. (2n=24) and C. micacea Marshal (2n=26) are essentially autotetraploid in origin and that C. scotica Druce is simply a morphological variant of C. officinalis. The chromosomal relationships of the tetraploids to each other and to the diploids in the genus are discussed and the possible routes for the formation of all the species from a single, 2n=12, basic taxon are given. Evidence for the existence of a genic mechanism causing C. officinalis to form only bivalents is given and the mode of evolution of such a mechanism discussed.     

Taxonomy and breeding system in a new species of Scrophularia L. (Scrophulariaceae) from Morocco

A new species of the genus Scrophularia, S. fontqueri Ortega-Olivencia & Devesa, is described for the Western Rif mountains in Morocco. Similarities and differences with the most closely related species (S. auriculata Loefl. ex L. and S. viciosoi Ortega-Olivencia & Devesa) are indicated, and ecological and distribution data are provided. The new species displays a high degree of polyploidy (2n = 56), and has palynological characteristics similar to those of other species in this genus. The new species shows protogynous dichogamy and produces considerable amounts of nectar in both sexual phases. Nectar secretion was maximum during the early hours of the morning. Mean longevity of the flowers was 2.66 days. Both nectar secretion and floral longevity correlated strongly with mean daytime air temperature. Pollination experiments showed that interaction with pollinators is necessary for reproduction, and gametophytic homomorphic self-incompatibility was documented. This feature was confirmed by observation of pollen tubes after hand self-pollination. The seed/ovule ratio was very low.     

Taxonomy of theHieracium alpinum group in the sudeten Mts., the West and the Ukrainian East Carpathians

A taxonomic revision of theHieracium alpinum group (sensu Flora Europaea) in the Sudeten Mts., the West and the Ukrainian East Carpathians is provided. Six species are distinguished in the area studied, viz.Hieracium alpinum, H. halleri, H. augusti-bayeri, H. melanocephalum, H. tubulosum, andH. schustleri. H. alpinum occurs throughout the mountain ranges studied, three other taxa are endemic to the Sudeten Mts. (H. melanocephalum, H. tubulosum, H. schustleri), one is confined to the West Carpathians (H. halleri, in addition to the Alps) and one is endemic to the Ukrainian East Carpathians (H. augusti-bayeri). A diploid cytotype (2n=18) was ascertained inH. alpinum from the Ukrainian East Carpathians and the same chromosome number was found forH. augusti-bayeri. An agamospermous mode of reproduction was confirmed for the triploid cytotype ofH. alpinum, the triploidH. melanocephalum andH. halleri and the tetraploidsH. tubulosum andH. schustleri; the diploid taxa were found to be sexual. Pollen production in diploid taxa is high and pollen grains are homogeneous in size; triploid species, as well as tetraploidH. tubulosum, do not produce polllen; tetraploidH. schustleri has pollen grains of variable size. Data on the ecology and distribution of the species are also given.     

Cytotaxonomy and breeding system of the genusBiscutella (Cruciferae)

Chromosome counts were determined for 46 populations ofBiscutella representing 28 taxa. The genus was found to contain diploid taxa with 2n = 12, 16 and 18, tetraploid taxa with 2n = 36 and hexaploid taxa having 2n = 54.B. laevigata L. s. l. consists of diploid and tetraploid populations which are poorly differentiated morphologically. TetraploidB. laevigata s. l. and hexaploidB. variegata Boiss. & Reuter (s. l.) are characterized by chromosomal instability. The variation in chromosome numbers and the occurrence of polyploidy is discussed in relation to the taxonomy of the genus. An investigation of the breeding system showed that most of the annual species were self-compatible and partly inbreeding and most of the perennial species self-incompatible and, therefore, outbreeding, while one annual species,B. cichoriifolia Loisel., showed both systems.     

The infrageneric classification of biscutella (Cruciferae)

A brief historical taxonomic sketch ofBiscutella is given. Revisionary study of the genus throughout its geographic areas has led to an infrageneric classification. Two subgenera are recognized, one with two sections.     

Taxonomy of the genusBrimeura (Hyacinthaceae)

A taxonomic reevaluation of two little-knownBrimeura taxa,B. fontqueri (Pau)Speta andB. duvigneaudii (L. Llorens)Rosselló et al., has been made.Brimeura fontqueri, described from the Iberian peninsula, has been put into synonymy ofB. amethystina (L.)Salisb., since it could not be distinguished on morphological, anatomical or cytogenetic grounds.Brimeura duvigneaudii, from the Balearic Islands, is closely related toB. amethystina and has 2n=28 chromosomes. It differs from the latter by its naked bulbs lacking dark cataphylls, and its narrower leaves and whitish corollas. Accessory chromosomes are reported for the first time in the genus. Karyological instability (with chromosome numbers ranging from 2n=28 to 42) is reported for a population ofB. fastigiata (Viv.)Chouard. A key to the recognized taxa ofBrimeura is provided.     

Spatial Variation in the Selective Scenarios of Hormathophylla spinosa (Cruciferae)

The effects of multispecific systems containing both mutualistic and antagonistic interacting organisms on the evolution of plant traits have seldom been analyzed. We studied the selection exerted by several species of herbivores and pollinators in three populations of Hormathophylla spinosa (Cruciferae) in the Sierra Nevada (Spain) over 4 yr by using path analyses and structural equation modeling (SEM). The main selective pressures in our study sites were ungulates and pollinators. However, the importance of each kind of interacting organism differed among populations. Our results indicate a selection mosaic among populations of H. spinosa in the Sierra Nevada caused by the spatial variation in the relative importance of different interactions as selective pressures. We found two main selective scenarios, depending on the presence or absence of ungulates. In the populations with low ungulate pressure, there was positive phenotypic selection in flower number per plant and in flower density (mediated by nectarivorous pollinators). In the two populations with high ungulate pressure, there was a strong positive, ungulate-mediated selection in thorn density. Our results suggest that the application of SEM to several populations simultaneously monitored might help to isolate the major selection pressures on local populations and identify potential differences in selection among populations, becoming a useful exploratory approach to study the geographical variation of selection in complex systems.