We report here the isolation and characterization of microsatellites, or simple sequence repeats (SSRs), in Brassica rapa. The size-fractionated genomic library was screened with (GA)15 and (GT)15 oligonucleotide probes. A total of 58 clones were identified as having the microsatellite repeats, and specific primer pairs were designed for 38 microsatellite loci. All primer pairs, except two, amplified fragments having the sizes expected from the sequences. Of the 36 primer pairs, 35 amplified polymorphic loci in 19 cultivars of B. rapa, while monomorphism was observed in only one primer pair. A total of 232 alleles was identified by the 36 primer pairs in 19 cultivars of B. rapa, and these primer pairs were examined also in nine Brassicaceae species. Most of the 36 primer pairs amplified the loci in the Brassicaceae species. Segregation of the microsatellites was studied in an F2 population from a cross of doubled-haploid lines DH27 x G309. The microsatellites segregated in a co-dominant manner. These results indicate that the microsatellites isolated in this study were highly informative and could be useful tools for genetic analysis in B. rapa and other related species.

The review of the possibilities to use interspecific hybridisation between Brassica napus and some wild species in the family of Brassicaceae for introduction of resistance to the important fungal pathogens is presented. A large collection of wild relatives as resources of resistance to Leptosphaeria maculans, Alternaria brassicola, A. raphani and Plasmodiophora brassicae has been screened. Successful hybridisation with Brassica napus has been achieved using Brassica elongata, B. fructiculosa, B. souliei, Diplotaxis tenuifolia, Hirschfeldia incana, Coincya monensis and Sinapis arvensis.

The review of the possibilities to use interspecific hybridisation between Brassica napus and some wild species in the family of Brassicaceae for introduction of resistance to the important fungal pathogens is presented. A large collection of wild relatives as resources of resistance to Leptosphaeria maculans, Alternaria brassicola, A. raphani and Plasmodiophora brassicae has been screened. Successful hybridisation with Brassica napus has been achieved using Brassica elongata, B. fructiculosa, B. souliei, Diplotaxis tenuifolia, Hirschfeldia incana, Coincya monensis and Sinapis arvensis.

I examined glucosinolates, trypsin inhibitors (TI), and peroxidase (POD) activity in garlic mustard (Alliaria petiolata) plants growing naturally in Wright State University's Forest Preserve and in a common garden experiment in plants from the same populations conducted in the greenhouse. In the field, first-year plants expressed each defense, but defense levels varied significantly in plants from different sites in the forest. Patterns in site variation were consistent for glucosinolate and POD, but not for TI. The TI and POD levels were increased by mechanical wounding, but glucosinolate levels were unaffected. In the greenhouse, plants expressed each defense at higher levels than in the field, but defense levels did not vary among plants collected from each site in the field. The POD activity was increased by wounding, but glucosinolate and TI levels where unaffected. Plants from each site varied in height and leaf length when measured shortly after transplantation, but site differences substantially diminished after 4 wk. Site-based variation in defense expression in the field, which disappeared in the greenhouse, was presumably related to differences in environmental quality among the sites. Sites were shown to vary in soil moisture content, soil pH, nutrient levels, and presumably light quantity or quality. Despite an apparent lack of genetic variation in defense across sites in the field, the constitutive expression of these three chemical defenses, increases due to wounding, and phenotypic variation across sites could reduce herbivore success on garlic mustard individuals and slow the rate of herbivore adaptation to garlic mustard populations.

Thesis (MSc)--Stellenbosch University, 2002. | ENGLISH ABSTRACT:Several authors regard the subdivision of the large genus Heliophila as unsatisfactory and in need of a detailed taxonomic study. Previous studies on this genus were based exclusively on gross external morphological characters. The present study investigates patterns of variation in Heliophila in order to identify taxonomically informative characters that could be used in the subdivision of this large genus. The study differs from previous studies in Heliophila because, in addition to macro-morphology, it employs micro- morphological (SEM) and palynological evidence to elucidate the subdivisio.n of Heliophila. The study emanates from a taxonomic revision of Heliophila proposed by Sander (1860), in which he subdivided the genus into six sections, based on the variation in fruit characters. Subsequent authors ignored the sections, regarding the generic subdivision as insufficiently supported, hence unsatisfactory . The results of cluster analysis, which are based on all the characters examined in the study (overall variation), propose the subdivision of Heliophila into three main clades: Micromorphological characters of fruits, seeds, and leaves are consistently found to be more congruent with the phenogram than macro-morphological characters of the same organs. This suggests that micro-morphological characters are taxonomically informative in Heliophila and should prove very important in a future phylogenetic classification of the genus. Palynological characters were found to be of limited taxonomic importance in the subdivision of the genus. | AFRIKAANSE OPSOMMING: Verskeie outeurs beskou die onderverdeling van die groot genus Heliophila as onbevredigend, en meen dat dit 'n gedetaileerde taksonomies studie benodig. Vorige studies op hierdie genus het slegs op ekstern morfologiese kenmerke gekonsentreer. In die huidige studie word patrone van variasie in Heliophila ondersoek met die oog op 'n moontlike onderverdeling van die genus, en taksonomies betek~nisvolle kenmerke wat in hierdie verband gebruik kan word, word geidentifiseer. Die huidige stud'e verskil van vorige studies daarin dat, benewens makro-morfologiese kenmerke, dit ook mikro-~rfologiese tegnieke (SEM) en palinologiese kenmerke gebruik om 'n sinvolle subverdeling van Heliophila te probeer vind. Die huidige studie spruit uit 'n taksonomiese hersiening van Heliophila deur Sonder (1860), waarin hy voorstel dat die genus in ses seksies verdeel word op grond van variasie in vrug kenmerke. Hierdie generiese onderverdeling en die voorgestelde seksies is deur latere outeurs as onbevredigend beskou, en is meestal in die literatuur geignoreer. Die resultate van fenetiese analise, wat op alle ingeslote kenmerke gebaseer is (algehele variasie), stel voor dat Heliophila in drie hoof groepe verdeel moet word. Taksonomies belangrike kenmerke wat hierdie onderverdeling ondersteun sluit in blaartipe, variasie in blaar-oppervlakke (SEM), variasie in die aard van die saadhuid (SEM) en variasie in vrugoppervlakke (SEM). Palinologiese en makro-morfologiese kenmerke was van geringe waarde in die onderverdeling van die genus.

Plants are attacked by a broad array of herbivores and pathogens. In response, plants deploy an arsenal of defensive traits. In Brassicaceae, the glucosinolate-myrosinase complex is a sophisticated two-component system to ward off opponents. However, this so-called "mustard oil bomb" is disarmed by a glucosinolate sulfatase of a crucifer specialist insect, diamondback moth, Plutella xylostella (Lepidoptera: Plutellidae). Sulfatase activity of this enzyme largely prevents the formation of toxic hydrolysis products arising from this plant defense system. Importantly, the enzyme acts on all major classes of glucosinolates, thus enabling diamondback moths to use a broad range of cruciferous host plants.

Developmental and physiological studies of roots are frequently limited to a post-germination stage. In Arabidopsis, a developmental change in the root meristem architecture during plant ontogenesis has not previously been studied and is addressed presently. Arabidopsis thaliana have closed root apical organization, in which all cell file lineages connect directly to one of three distinct initial tiers. The root meristem organization is dynamic and changes as the root ages from 1 to 4 wk post-germination. During the ontogeny of the root, the number of cells within the root apical meristem (RAM) increases and then decreases due to changes in the number of cortical layers and number of cell files within a central cylinder. The architecture of the initial tiers also changes as the root meristem ages. Included in the RAM's ontogeny is a pattern associated with the periclinal divisions that give rise to the middle cortex and endodermis; the three-dimensional arrangement of periclinally dividing derivative cells resembles one gyre of a helix. Four- or 5-wk-old roots exhibit a disorganized array of vacuolated initial cells that are a manifestation of the determinate nature of the meristem. Vascular cambium is formed via coordinated divisions of vascular parenchyma and pericycle cells. The phellogen is the last meristem to complete its development, and it is derived from pericycle cells that delineate the outer boundary of the root.

This paper reports on 6-year trials (1992-1998) conducted mainly in the framework of the PrisCA Project, in various environments of Italy, on different species of Brassicaceae capable of producing seeds rich in erucic acid - Brassica carinata, B. juncea, B. rapa, Sinapis alba and Crambe abyssinica - and on species characterized by unusual fatty acids - Calendula officinalis L. (calendic acid), Camelina sativa L. (linolenic acid), Coriandrum sativum L. (petroselinic acid), Cuphea P. Browne (medium chain saturated fatty acids), Euphorbia lagascae Sprengel (epoxyacids), Euphorbia lathyris L. (oleic acid), Eruca sativa L. (erucic acid), Limnanthes alba Hartw. ex Benth (long chain fatty acids), Lepidium sativum L. (oleic and linolenic acid), Lesquerella fendleri (Gray) Wats. (hydroxyacids), Madia sativa Molina (linoleic acid), Oenothera biennis and Borago officinalis (gamma-linolenic), Vernonia galamensis (Cass.) Less. and Stokesia laevis (epoxyacids) - in order to assess their potential for use as industrial crops | Vengono riportati e discussi i risultati della sperimentazione poliennale (1992-1998) condotta prevalentemente nell'ambito del Progetto PRisCA, in differenti ambienti del Paese, su specie diverse di Brassicaceae in grado di produrre semi ricchi di acido erucico - Brassica carinata, B. juncea, B. rapa, Sinapis alba e Crambe abyssinica - e su specie caratterizzate da oli con acidi grassi inusuali - Calendula officinalis L. (acido calendico), Camelina sativa L. (acido linolenico), Coriandrum sativum L. (acido petroselinico), Cuphea P. Browne (acidi grassi saturi a media catena), Euphorbia lagascae Sprengel (epossiacidi), Euphorbia lathyris L. (acido oleico), Eruca sativa L. (acido erucico), Limnanthes alba Hartw. ex Benth (acidi grassi a catena lunga), Lepidium sativum L. (acido oleico e linolenico), Lesquerella fendleri (Gray) Wats. (idrossiacidi), Madia sativa Molina (acido linoleico), Oenothera biennis e Borago officinalis (gamma-linolenico), Vernonia galamensis (Cass.) Less. e Stokesia laevis (epossiacidi) - al fine di valutare la loro possibile utilizzazione come colture industriali

The definitive version is available at www.blackwell-synergy.com | We present a new set of 12 highly polymorphic simple sequence repeat primer sequences for use with Brassica species. These new primers, and four from A.K.S. SzewcMcFadden and colleagues, were tested in four Brassica species (B. rapa, B. napus, B. oleracea and B. nigra). Most primers successfully amplified products within all species and were polymorphic. Due to the risk of gene flow from GM oilseed rape to its wild relatives, hybrid formation in the Brassicaceae is of great interest. We identify six primer pairs as specific to the A, B or C genomes that could be used to identify such hybrids. | Andrew J Lowe, Alexandra E Jones, Alan F Raybould, Martin Trick, Carolyn L Moule, Keith J Edwards

Colour photos. Final web-ready size: JPEG, 72 ppi. Photo 1: 9.7 kb; Photo 2: 14.8 kb; Photo 3: 15.7 kb; Photo 4: 15.1 kb; Photo 5: 11.5 kb; Photo 6: 10.2 kb; Photo 7: 8.71 kb; Photo 8: 10.2 kb; Photo 9: 10.7 kb. Original TIFF file housed at the Dept. of Paraclinical Sciences, Section Pharmacology and Toxicology, University of Pretoria. | DISTRIBUTION: Not usually cultivated as animal feed. Japanese radishes & kale are produced as feed for livestock. When market prices are low or crops are damaged by hail, etc., it is sometimes fed to stock. | BOTANICAL DESCRIPTION: Turnips, radishes, cabbages, cauliflowers, and Brussel sprouts (Brassicaceae) are all vegetables which are produced for human consumption. They do not grow naturally in the wild. The tubers of some are utilised, (turnips, radishes, etc.) , while the leaves and flowers and fruit of others are consumed (cabbages, cauliflowers, etc.). Weeds like wild radish and wild mustard do grow wild. | TOXIC PRINCIPLE: Haemopoietic: • The toxic principle of the Brassicaceae is dimethyl disulphide produced from SMCO. • Dimethyl disulphide reacts with the thiol group of GSH which is then not available to prevent oxidative damage of the red blood cell. • With oxidative damage the haemoglobin is denatured and the protein precipitate as Heinz bodies. • The affected erythrocytes are removed by the RE-system or intravascular haemolysis ensues resulting in haemoglobinaemia and haemoglobinuria. Urogenital: Organic nitriles and glucosinolates are goitrogenic and teratogenic. | SYNDROMES: Heinz body anemia. | SYSTEMS AFFECTED: Haemopoietic and urogenital systems. | CLINICAL SIGNS: Acute: • Haemoglobinuria. Pale, anaemic mucous membranes • Icterus (jaundice) • Diarrhoea • Ruminal stasis Chronic: • Subclinical anaemia. • Ill-thrift. • Poor milk production, poor growth, emaciation. • Infertility. | NECROPSY: Macroscopical findings: Icterus. Anemia – pale mucous membranes, watery blood. Haemoglobinuria and dark pigmented kidneys. Git irritation. | TREATMENT: • Remove feed immediately • Blood transfusion in valuable or stud animals. | PREVENTION: • Brassica’s should be fed only in limited quantities • Feed with other good quality hay, concentrate, etc. • Can slowly increase the percentage of Brassica’s in the ration • Avoid frost damaged plants - may have a higher concentration of the toxic principle. | http://www.library.up.ac.za/vet/poison