Ploidy and transcriptomic analyses of reproductive tissues in Alfalfa

Alfalfa, a widely cultivated forage crop, holds significant importance as a model species for legume forage crops due to its exceptional qualities in terms of yield quality and quantity. Its natural occurrence of unreduced gametes and tetraploid accessions within the Medicago sativa complex makes alfalfa an ideal candidate for studying sexual polyploidization processes and their applications in plant breeding. This research focused on determining the ploidy levels and analyzing the transcriptome of reproductive whorls in alfalfa plants resulting from different crosses. Ploidy levels were determined using flow cytometry, and tetraploid individuals were identified in both BSP and USP populations. RNA-seq analysis was performed to explore gene expression patterns in various developmental stages of reproductive whorls. Differential gene expression analysis revealed that the pollinated flower stage had the highest number of differentially expressed genes, indicating its crucial role in reproductive processes. Several genes associated with the negative and positive regulation were discovered suggesting their potential roles. This study enhances our understanding of ploidy determination, gene expression patterns, and the molecular mechanisms underlying reproductive processes in alfalfa. The findings have implications for alfalfa breeding and improvement programs by offering insights into the genetic regulation of plant reproduction. Further research is necessary to validate the functions of the identified genes and uncover their specific roles in reproductive processes.