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Metabolomics is developing toward an integral component of functional genomics approaches. The large structural diversity of plant metabolites requires different analytical techniques for broad metabolite analysis. In addition, new bioinformatics tools and databases are necessary for data analysis and storage. This chapter describes the resources available for comprehensive analysis of plant secondary metabolites focusing on Arabidopsis thaliana and Brassica species. In particular, a platform for non-targeted profiling of semi-polar plant metabolites based on liquid chromatography coupled to mass spectrometry is described. [ABSTRACT FROM AUTHOR]

Brassica oleracea is one of the most important species of the Brassicaceae family because the species includes some of the most economically important vegetables in the world. Common heading cabbage and cauliflower are the most widely grown crops of this species, but broccoli is also now emerging rapidly as a world vegetable. The wide center of origin for this species is the Mediterranean Basin, and primitive forebears of our modern B. oleracea crop forms have been cultivated and selected for several millennia. Undoubtedly, the diverse array of wild forms found in this species and other very closely related species played very important roles in stimulating the occurrence of morphological variation within and among the B. oleracea crops as they underwent development. In the years following the rediscovery of Mendel΄s work, many scientists studied the underlying genetic factors controlling the divergent morphologies within the species. This was of interest not only from a basic scientific standpoint, but also due to the practical necessity of understanding the complex sets of genes that combine and give rise to a specific crop form like heading cabbage or cauliflower. This knowledge is crucial in moving genes between crops in the process of breeding improved varieties. Secondary plant metabolites have emerged as key components of crops within this species because they appear to contribute added-value to the various crops by conferring intrinsic healthful effects on populations that consume these vegetables. Among the various components believed to confer a chemoprotective effect in B. oleracea, glucosinolates, and isothiocyanates have received the most attention in recent years and are considered in detail herein. The study of B. oleracea genetics has been greatly advanced during the modern era of gene study at the molecular level. Although the species has presented challenges, scientists focused on these crops are now mapping genes to specific chromosomes and the genome is well on its way to being sequenced. As knowledge advances at the molecular level, a fuller understanding of gene sequences and there relations to morphology, disease resistance, phytochemical make-up, and other important traits are being realized in B. oleracea. [ABSTRACT FROM AUTHOR]

Brassica crops are grown worldwide for oil, food and feed purposes, and constitute a significant economic value due to their nutritional, medicinal, bioindustrial, biocontrol and crop rotation properties. Insect pests cause enormous yield and economic losses in Brassica crop production every year, and are a threat to global agriculture. In order to overcome these insect pests, Brassica species themselves use multiple defence mechanisms, which can be constitutive, inducible, induced, direct or indirect depending upon the insect or the degree of insect attack. Firstly, we give an overview of different Brassica species with the main focus on cultivated brassicas. Secondly, we describe insect pests that attack brassicas. Thirdly, we address multiple defence mechanisms, with the main focus on phytoalexins, sulphur, glucosinolates, the glucosinolate-myrosinase system and their breakdown products. In order to develop pest control strategies, it is important to study the chemical ecology, and insect behaviour. We review studies on oviposition regulation, multitrophic interactions involving feeding and host selection behaviour of parasitoids and predators of herbivores on brassicas. Regarding oviposition and trophic interactions, we outline insect oviposition behaviour, the importance of chemical stimulation, oviposition-deterring pheromones, glucosinolates, isothiocyanates, nitriles, and phytoalexins and their importance towards pest management. Finally, we review brassicas as cover and trap crops, and as biocontrol, biofumigant and biocidal agents against insects and pathogens. Again, we emphasise glucosinolates, their breakdown products, and plant volatile compounds as key components in these processes, which have been considered beneficial in the past and hold great prospects for the future with respect to an integrated pest management. [ABSTRACT FROM AUTHOR]