Rosaceae plants comprise numerous fruit crops with huge economic values. The lack of genomic characteristics has largely blocked our understanding about the Rosaceae gene and plastome evolution. Here, we analyzed 121 Rosaceae chloroplast (cp) genomes of 51 taxa from 19 genera, predominantly including the Cerasus plants and their relatives. To our knowledge, we generated the first comprehensive map of genomic variation across Rosaceae plastomes. Protein-coding genes of Rosaceae plastomes were characterized with high proportion (over 50%) of synonymous variants and InDels with multiple triplets. Four photosynthesis-related genes were under Darwin selection, which are unique in woody fruit trees of Rosaceae. We detected considerable variations in genome size among Rosaceae plastomes and observed trivial and obvious structural variation in the examined cp genomes of tribes Pyrodae and Amygdaleae. Phylogenomic analyses and molecular dating highlighted the independent evolution of true cherry, dwarf cherry and relatives. Our findings strongly support to taxonomically treat the monophyletic true cherry group as a separate genus excluding dwarf cherry. High levels of genomic differentiation and distinct phylogenetic relationships implied independent origins and domestication between fruit cherries, particularly between cultivated Cerasus psuedocerasus and Cerasus avium. We further proposed an evolutionary model to elucidate multiple genomic introgression events among true cherries occurring since ~15 Mya. Well-resolved maternal phylogeny suggested that the cultivated C. pseudocerasus might be originated from Longmenshan Fault zone, the eastern edge of Himalaya-Hengduan Mountains, where they have subjected to frequent genomic introgression between its presumed wild ancestors and other close relatives. In conclusion, comparative analyses of plastomes and chloroplast genes detected diverse evolutionary behaviors and divergent adaptive selection in Rosaceae. We provide robust evidences for the independent origins and domestication of fruit cherries.

The composition and content of glucosinolates were investigated in the edible parts (petioles, peel, and flesh) of tuber mustard, bamboo shoots mustard, and baby mustard by high performance liquid chromatography to reveal the association between the different cooking methods and their glucosinolate profiles. Eight glucosinolates were identified from tuber mustard and baby mustard, including three aliphatic glucosinolates, four indole glucosinolates, and one aromatic glucosinolate. Only six of the eight glucosinolates were detected in bamboo shoots mustard. The results show that the distribution and content of glucosinolates varied widely among the different tissues and species. The highest contents of glucosinolates in tuber mustard, bamboo shoots mustard, and baby mustard were found in flesh, petioles, and peel, respectively. The content of total glucosinolates ranged from 5.21 μmol/g dry weight in bamboo shoots mustard flesh to 25.64 μmol/g dry weight in baby mustard peel. Aliphatic glucosinolates were predominant in the three stem mustards, followed by indole and aromatic glucosinolates. Sinigrin was the predominant glucosinolate in the three stem mustards. Sinigrin content in tuber mustard was slightly higher than that in baby mustard and much higher than that in bamboo shoots mustard, suggesting that the pungent-tasting stem mustards contained more sinigrin. In addition, a principal components analysis showed that bamboo shoots mustard was distinguishable from the other two stem mustards. A variance analysis indicated that the glucosinolates were primarily influenced by a species × tissue interaction. The correlations among glucosinolates were also analyzed.