Brassicaceae (Cruciferae) Family,Plant Biotechnology,and Phytoremediation

Plants represent a natural environmentally safe way to clean or remediate contaminated sites. Members of the Brassicaceae or Cruciferae plant family have a key role in phytoremediation technology. Many wild crucifer species are known to hyperaccumulate heavy metals and possess genes for resistance or tolerance to the toxic effects of a wide range of metals. Metal uptake, sensitivity, and sequestration have been studied extensively in Arabidopsis thaliana, and a number of heavy metal-sensitive and ion-accumulating mutants have been identified. This species is a likely source of genes for phytoremediation. Within the Brassicaceae, Brassica and other crop species are likely candidates for phytoremediation. There is a wealth of information on the agronomics of the economically important members and biomass production can be extensive. Many of these species are well adapted to a range of environmental conditions. Some species are tolerant to high levels of heavy metals, and there is the potential to select superior genotypes for phytoremediation. They are well suited to genetic manipulation and in vitro culture techniques and are attractive candidates for the introduction of genes aimed at phytoremediation. Biotechnology and molecular biology are valuable tools for studies of metal accumulation and tolerance in hyperaccumulating species and for the transfer of relevant genes into crucifer species suitable for phytoremediation. The purpose of this article is to review the potential use of both wild and cultivated members of the Brassicaceae in phytoremediation.     

Secondary Metabolites of Micromycetes in Plants of the Family Brassicaceae (Cruciferae)

Biology Bulletin - Indirect competitive enzyme immunoassay was used to detect the occurrence of 16 mycotoxins in wild herbaceous plants of the Brassicaceae (Cruciferae) family typical for...     

Chemosystematic studies on certain species of the family Brassicaceae (Cruciferae) in Egypt

The flavonoids of nine selected species belonging to different tribes of family Brassicaceae (Cruciferae) native to Egypt were surveyed, viz. Rorippa palustris, Coronopus squamatus, Eremobium aegyptiacum, Moricandia nitens, Brassica tournefortii, Farsetia aegyptia, Matthiola livida, Anastatica hierochuntica and Sisymbrium irio. Thirty-eight compounds were isolated and identified, which included six flavonol aglycones, 24 flavonol glycosides including 14 flavonol 3,7-diglycosides, one flavone aglycone, three flavone O–glycosides, two glycoflavones and two dihydroflavonoids. A numerical analysis based on a combination of 97 morphological, anatomical and chemical characters revealed two series, two subseries, two clusters and two groups. The interrelationships between the studied species are discussed.     

Cytological studies of Brassicaceae Burn. (Cruciferae Juss.) from Western Himalayas

Cytological studies have been carried out on 12 species of Brassicaceae Burn. on population basis from different geographical areas of Kashmir and Himachal Pradesh in the Western Himalayas. Variable chromosome reports for Barbaraea intermedia (n = 16), Cardamine loxostemonoides (n = 8), Nasturtium officinale (n = 8), Sisymbrium orientale (n = 14) on world-wide basis have been added to the previous reports of these species. The chromosome numbers in seven species as Barbaraea intermedia (n = 8), B. vulgaris (n = 8), Capsella bursa-pastoris (n = 8), Descuriania Sophia (n = 10), Rorippa islandica (n = 8), Sisymbrium strictum (n = 7) and Thlaspi alpestre (n = 7) have been worked out for the first time from India. The meiotic course in the populations of seven species such as Barbaraea intermedia, Capsella bursa-pastoris, Coronopus didymus, Descuriania sophia, Nasturtium officinale, Sisymbrium orientale and S. strictum varies from normal to abnormal while all the populations of two species Barbaraea vulgaris and Sisymbrium irio show abnormal meiotic course. Meiotic abnormalities are in the form of cytomixis, chromosomal stickiness, unoriented bivalents, inter-bivalent connections, formation of laggards and bridges, all resulting into abnormal microsporogenesis. Heterogenous sized fertile pollen grains and reduced reproductive potentialities have invariably been observed in all the meiotically abnormal populations. However, the meiotic course in all the populations of Cardamine loxostemonoides, Rorippa islandica and Thalspi alpestre is found to be normal with high pollen fertility.     

Nomenclatural changes in schizachyrium (Poaceae)

Two morphological variants ofSchizachyrium hirtiflorum are reduced to varietal rank underS. sanguineum. Schizachyrium semiberbe is included as a synonym of the typical variety ofS. sanguineum.     

龙胆科獐牙菜属新分类纲要

獐牙菜属是龙胆科中的一个大属,广泛分布于亚洲、北美洲、欧洲和非洲.本文报道獐牙菜属下的两个新组(sect.Montana和sect.Echinulata)和七个新系(ser.Repentes,ser.Kilimandscharicae,ser.Coombosae,ser.Japonicae,ser.Swertopsis,ser.Pumilae和ser.Abyssinicae).同时对獐牙菜属中的一些类群进行了分类修订,本分类纲要将被獐牙菜属世界专著采用.     

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.     

Cytotype diversity and genome size variation in eastern Asian polyploid Cardamine (Brassicaceae) species

Background and Aims

Intraspecific ploidy-level variation is an important aspect of a species'' genetic make-up, which may lend insight into its evolutionary history and future potential. The present study explores this phenomenon in a group of eastern Asian Cardamine species.

Methods

Plant material was sampled from 59 localities in Japan and Korea, which were used in karyological (chromosome counting) and flow cytometric analyses. The absolute nuclear DNA content (in pg) was measured using propidium iodide and the relative nuclear DNA content (in arbitrary units) was measured using 4,6-diamidino-2-phenylindole fluorochrome.

Key Results

Substantial cytotype diversity was found, with strikingly different distribution patterns between the species. Two cytotypes were found in C. torrentis sensu lato (4x and 8x, in C. valida and C. torrentis sensu stricto, respectively), which displays a north–south geographical pattern in Japan. Hypotheses regarding their origin and colonization history in the Japanese archipelago are discussed. In Korean C. amaraeiformis, only tetraploids were found, and these populations may in fact belong to C. valida. C. yezoensis was found to harbour as many as six cytotypes in Japan, ranging from hexa- to dodecaploids. Ploidy levels do not show any obvious geographical pattern; populations with mixed ploidy levels, containing two to four cytotypes, are frequently observed throughout the range. C. schinziana, an endemic of Hokkaido, has hexa- and octoploid populations. Previous chromosome records are also revised, showing that they are largely based on misidentified material or misinterpreted names.

Conclusions

Sampling of multiple populations and utilization of the efficient flow cytometric approach allowed the detection of large-scale variation in ploidy levels and genome size variation attributable to aneuploidy. These data will be essential in further phylogenetic and evolutionary studies.     

Nomenclatural typifications in polygonum section echinocaulon (Polygonaceae)

The nomenclature and typification of all known species ofPolygonumi sectionEchinocaulon are clarified, and the correct names and synonyms are presented. Lectotypes are selected.     

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.     

Ecuadorian novelties in Blakea and Topobea (Melastomataceae)

Three new species of Melastomataceae (Blakeeae) are described:Blakea subpanduriformis, Topobea adscendens, andT. bullata. All are climbers endemic to the montane forests of the eastern slopes of the Andes in southern Ecuador. In this region, 35% of the Ecuadorian species and 41% of the endemic Ecuadorian species of Melastomataceae occur. The discovery of these three new endemic species underlines the diversity of Melastomataceae occurring on the slopes of the Andes in southeastern Ecuador.     

Nomenclatural changes in Myrteola and Myrceugenia (Myrtaceae)

The following new combinations are made:Myrteola phylicoides (Benth.) Landrum,Myrteola phylicoides var.glabrata (Berg) Landrum,Myrceugenia alpigena var.fuliginea (Berg) Landrum,Myrceugenia ovata var.regnelliana (Berg) Landrum, andMyrceugenia pilotantha var.nothorufa (Legrand) Landrum.     

Nomenclatural changes in Polygonum section Echinocaulon (Polygonaceae)

As a result of comprehensive systematic study onPolygonum sectionEchinocaulon, three new nomenclatural changes are made:P. clarkei stat. et nom. nov.,P. subsagittatum stat. nov., andP. senticosum var.sagittifolium stat. nov.     

Nomenclatural changes in some intermountain penstemons (Scrophulariaceae)

Fifteen new combinations and one new binomial inPenstemon, to be used in a floristic treatment of the genus in theIntermountain Flora, are published herewith.     

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.     

Nomenclatural notes on Rhododendron sparsifolium (Ericaceae)

Based on examination of original material, we demonstrate that the name Rhododendron sparsifolium W. P. Fang was indeed validly published when first published in 1983. Meanwhile, we correct the collectors of two of the three type gatherings listed in the protologue, including the holotype. Furthermore, we propose to reduce R. hejiangense to the synonymy of R. sparsifolium on the basis of morphological comparisons.     

Germination behaviour in populations ofCapsella bursa-pastoris (Cruciferae)

Germination behaviour of variousCapsella bursa-pastoris populations collected from Scandinavia, Middle Europe and the Alps, was tested in unheated, non-illuminated greenhouses (46 populations) and in growth chambers using 5–7 alternating temperature regimes (16 populations). For all populations, the influence of temperature on germination rate is straightforward: the higher the temperature, the greater the germination. Germination capacity, however, may depend on the geographical region. There is also a strong seed age effect on both, rate and capacity of germination. Once dormancy was broken, seeds from all populations were able to germinate over the entire range of temperatures. Some populations revealed a more or less pronounced temperature optimum for germination capacity, others germinated equally well over the entire temperature range. This indicates genetic heterogeneity between populations. However, no correlation between germinability and any environmental pattern was detected. The data indicate thatCapsella bursa-pastoris has adopted a germination strategy which includes a broad temperature tolerance. Germination of wildCapsella plants seems to be regulated by the factors contributing to the inception and breaking of dormancy which depend on pre- and postharvest conditions. Adaptation in germination behaviour inCapsella bursa-pastoris is different from that in other life history traits (flowering behaviour, growth form parameters).