Genome-wide analysis of MADS-box families and their expressions in flower organs development of pineapple ( Ananas comosus (L.) Merr.).

MADS-box genes play crucial roles in plant vegetative and reproductive growth, better development of inflorescences, flower, and fruit. Pineapple is a typical collective fruit, and a comprehensive analysis of the MADS-box gene family in the development of floral organs of pineapple is still lacking. In this study, the whole-genome survey and expression profiling of the MADS-box family in pineapple were introduced. Forty-four genes were identified in pineapple, 39 of them were located on 18 chromosomes and five genes were distributed in five scaffolds. Twenty-two genes were defined as 15 pairs of segmental duplication events. Most members of the type II subfamily of genes had higher expression levels in floral organs compared with type I subfamily, thereby suggesting that of type II may play more crucial roles in the development of floral organs of pineapple. Six genes have significant tissue-specificity expression, thereby suggesting that they may participate in the formation of one or more floral organs. This study provides valuable insights into the role of MADS-box gene family in the floral organ development of pineapple.