Male sterility is an important factor in improving crop quality and yield through heterosis breeding. In this study, we analyzed the transcriptomes of male fertile (MF) and male sterile (MS) alfalfa flower buds using the Illumina HiSeq™ 4000 platform. A total of 54.05 million clean reads were generated and assembled into 65,777 unigenes with an average length of 874 bp. The differentially expressed genes (DEGs) between the MF and MS flowers at three stages of pollen development were identified, and there were 3832, 5678 and 5925 DEGs respectively in stages 1, 2 and 3. GO and KEGG functional enrichment analysis revealed 12, 12, 6 and 12 key branch-point genes involved in circadian rhythm, transcription factors, pollen development and flavonoid biosynthesis. Our findings provide novel insights into the mechanism of male sterility in alfalfa.

雄性不育是通过杂种优势育种提高作物品质和产量的重要因素。在本研究中，我们使用 Illumina HiSeq™ 4000 平台分析了雄性可育 (MF) 和雄性不育 (MS) 苜蓿花蕾的转录组。总共生成了 5405 万条干净的 reads，并组装成 65777 个 unigenes，平均长度为 874 bp。鉴定了花粉发育三个阶段的MF和MS花之间的差异表达基因（DEGs），在第1、2和3阶段分别有3832、5678和5925个DEGs。GO和KEGG功能富集分析显示12、12 , 6 和 12 个关键分支点基因参与昼夜节律、转录因子、花粉发育和类黄酮生物合成。我们的研究结果为苜蓿雄性不育的机制提供了新的见解。