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Glucosinolates (GSLs) and GSL-associated genes are receiving increasing attention from molecular biologists due to their multifunctional properties. GSLs are secondary metabolites considered to be highly active in most Brassica species. Their importance has motivated the discovery and functional analysis of the GSLs and GSL hydrolysis products involved in disease development in brassicas and other plants. Comprehensive knowledge of the GSL content of Brassica species and the molecular details of GSL-related genes will help elucidate the molecular control of this plant defense system. This report provides an overview of the current status of knowledge on GSLs, GSL biosynthesis, as well as hydrolysis related genes, and GSL hydrolysis products that regulate fungal, bacterial, and insect resistance in cabbage and other brassicas. [ABSTRACT FROM AUTHOR]

Bacterial fruit blotch (BFB), caused by Acidovorax citrulli, is an economically devastating disease in melon. Molecular characterization of causal strains and identification of sources of resistance are necessary to control this important disease. Many strains of BFB were identified by partial sequencing and documented in GenBank. Recently, there was an outbreak of BFB strain NIHHS15-280 in melon fields (Goksung, Jeonnam, Korea) that severely hampered melon production in Korea. For this reason, we characterized NIHHS15-280 by partially sequencing the 16S rRNA gene using PCR-based markers. The partial sequence of the 16S rRNA gene of NIHHS15-280 was much more similar to A. citrulli strains associated with melon and watermelon hosts than other cucurbit hosts. A PCR-based assay identified the strain (NIHHS15-280) as belonging to A. citrulli group I, which predominantly infects non-watermelon cucurbits (virulent to melon). Thirty-five melon genotypes were screened against NIHHS15-280 in a detached-leaf inoculation assay. The lack of visible disease symptoms 11 days after inoculation in lines PI353814 and PI140471 indicated these to be highly resistant lines, whereas moderate resistance was observed in lines PI420145 and SCNU1154 and cultivars ME6 and ME5. Also, the most resistant lines were corroborated by a fruit inoculation assay. The characterized A. citrulli strain NIHHS15-280 (group I) and identified resistant lines will serve as a valuable resource for further genetic studies and improvement of BFB resistance in melon. [ABSTRACT FROM AUTHOR]

Cabbage (Brassica oleracea var. capitata) is the most popular leafy vegetable; however, its quality as a vegetable depends on its growth stage. Premature bolting triggered by low temperatures leads to a reduction of yield and quality of cabbage. Late bolting is preferred by growers to increase market value, whereas early bolting plants are ideal for quality seed production. Herein, we reported a gene BolPrx.2 annotated as Q9FLC0 in the SwissPort, involved in bolting time variation in cabbage and designed molecular markers to characterize early- and late-bolting cabbage populations and lines. The BolPrx.2 gene encodes a peroxidase domain and has been identified as a candidate showed almost similar effect as the previously reported MADS-box domain-containing FLC genes for controlling bolting time. An insertion/deletion (InDel) variation in intron1 has been identified as a causal factor for variation between late- and early-bolting inbred lines. By using this InDel, we designed molecular markers for characterizing the bolting time variation and validated them with 141 F2 generation plants. These markers predicted about 84% of the variation within the population and commercial lines. Therefore, it could be a potential genetic tool to predict bolting time variation and support marker-assisted back crossing (MABC) programs for developing desired bolting types of cabbage cultivars. [ABSTRACT FROM AUTHOR]