The SWEET (sugars will eventually be exported transporter) family was identified as a new class of sugar transporters that function as bidirectional uniporters/facilitators and facilitate the diffusion of sugars across cell membranes along a concentration gradient. SWEETs are found widely in plants and play central roles in many biochemical processes, including the phloem loading of sugar for long-distance transport, pollen nutrition, nectar secretion, seed filling, fruit development, plant–pathogen interactions and responses to abiotic stress. This review focuses on advances of the plant SWEETs, including details about their discovery, characteristics of protein structure, evolution and physiological functions. In addition, we discuss the applications of SWEET in plant breeding. This review provides more in-depth and comprehensive information to help elucidate the molecular basis of the function of SWEETs in plants.

Hybrid production using lines with cytoplasmic male sterility (CMS) has become an important way to utilize heterosis in vegetables. Ogura CMS, with the advantages of complete pollen abortion, ease of transfer and a progeny sterility rate reaching 100%, is widely used in cruciferous crop breeding. The mapping, cloning, mechanism and application of Ogura CMS and fertility restorer genes in Brassica napus, Brassica rapa, Brassica oleracea and other cruciferous crops are reviewed herein, and the existing problems and future research directions in the application of Ogura CMS are discussed.

Broccoli (Brassica oleracea L. var. italica) is one of the most important vegetable crops cultivated worldwide. The market demand for broccoli is still increasing due to its richness in vitamins, anthocyanins, mineral substances, fiber, secondary metabolites and other nutrients. The famous secondary metabolites, glucosinolates, sulforaphane and selenium have protective effects against cancer. Significant progress has been made in fine-mapping and cloning genes that are responsible for important traits; this progress provides a foundation for marker-assisted selection (MAS) in broccoli breeding. Genetic engineering by the well-developed Agrobacterium tumefaciens-mediated transformation in broccoli has contributed to the improvement of quality; postharvest life; glucosinolate and sulforaphane content; and resistance to insects, pathogens and abiotic stresses. Here, we review recent progress in the genetics and molecular breeding of broccoli. Future perspectives for improving broccoli are also briefly discussed.

Cabbage (Brassica oleracea var. capitata) is a vegetable rich in glucosinolates (GSLs) that have proven health benefits. To gain insights into the synthesis of GSLs in cabbage, we systematically analyzed GSLs biosynthetic genes (GBGs) in the entire cabbage genome. In total, 193 cabbage GBGs were identified, which were homologous to 106 GBGs in Arabidopsis thaliana. Most GBGs in cabbage have undergone negative selection. Many homologous GBGs in cabbage and Chinese cabbage differed in expression patterns indicating the unique functions of these homologous GBGs. Spraying five exogenous hormones significantly altered expression levels of GBGs in cabbage. For example, MeJA significantly upregulated side chain extension genes BoIPMILSU1-1 and BoBCAT-3-1, and the expression of core structure construction genes BoCYP83A1 and BoST5C-1, while ETH significantly repressed the expression of side chain extension genes such as BoIPMILSU1-1, BoCYP79B2-1, and BoMAMI-1, and some transcription factors, namely BoMYB28-1, BoMYB34-1, BoMYB76-1, BoCYP79B2-1, and BoMAMI-1. Phylogenetically, the CYP83 family and CYP79B and CYP79F subfamilies may only be involved in GSL synthesis in cruciferous plants. Our unprecedented identification and analysis of GBGs in cabbage at the genome-wide level lays a foundation for the regulation of GSLs synthesis through gene editing and overexpression.

Main conclusion: Chitinase family genes were involved in the response of Brassica oleracea to Fusarium wilt, powdery mildew, black spot and downy mildew. Abstract Chitinase, a category of pathogenesis-related proteins, is believed to play an important role in defending against external stress in plants. However, a comprehensive analysis of the chitin-binding gene family has not been reported to date in cabbage (Brassica oleracea L.), especially regarding the roles that chitinases play in response to various diseases. In this study, a total of 20 chitinase genes were identified using a genome-wide search method. Phylogenetic analysis was employed to classify these genes into two groups. The genes were distributed unevenly across six chromosomes in cabbage, and all of them contained few introns (≤ 2). The results of collinear analysis showed that the cabbage genome contained 1–5 copies of each chitinase gene (excluding Bol035470) identified in Arabidopsis. The heatmap of the chitinase gene family showed that these genes were expressed in various tissues and organs. Two genes (Bol023322 and Bol041024) were relatively highly expressed in all of the investigated tissues under normal conditions, exhibiting the expression characteristics of housekeeping genes. In addition, under four different stresses, namely, Fusarium wilt, powdery mildew, black spot and downy mildew, we detected 9, 5, 8 and 8 genes with different expression levels in different treatments, respectively. Our results may help to elucidate the roles played by chitinases in the responses of host plants to various diseases.