Fan Baoli, Chen Qian, Zhou Shiyao, Zhang Yanting, Wang Yuwen, Shang Yuntao, Zhang Na, Liu Xiaoying, Wang Zhenying
College of Life Science, Tianjin Normal University, Tianjin, 300387, P.R. China.
Tianjin Key Laboratory of Water Resources and Environment, Tianjin Normal University, Tianjin, 300387, P.R. China.
J Plant Res. 2025 Apr 7. doi: 10.1007/s10265-025-01631-x.
The commercially cultivated garlic varieties are infertile, leading to challenges in conventional hybrid breeding. Xinjiang garlic exhibits visually normal development of both androecium and gynoecium, but most pollen grains are not viable, thus allowing for the identification of flower development-related genes through combined morphological, anatomical, and cytological methods with transcriptome analysis. The inflorescence meristem differentiation of Xinjiang garlic plants was initiated after the 6th-7th leaves emerged, implying the transition from vegetative growth to reproductive growth. With the development of flower organs after bolting, normal pollen mother cell meiosis but no viable pollen grains were detected through triphenyl tetrazolium chloride (TTC) staining. Delayed tapetal degeneration, the gap between the tapetum and the middle layer, and degenerating and aborting anther are visible during anther development. There were 25 differentially expressed MYB genes and 64 flowering pathway related genes at different stages of flower development. The R2R3-MYB genes enriched in Module 22 are involved in the development of the tapetum and pollen. The co-expression network analysis showed that most MYB genes are related to flowering regulatory genes. The expression pattern of MYB35, MYB26, MYB80 and MMD1 may cause delayed degradation of the tapetum, or abnormal development of the pollen wall leading to pollen abortion.
商业化种植的大蒜品种不育，这给传统杂交育种带来了挑战。新疆大蒜的雄蕊和雌蕊在外观上发育正常，但大多数花粉粒没有活力，因此可以通过形态学、解剖学、细胞学方法与转录组分析相结合来鉴定与花发育相关的基因。新疆大蒜植株的花序分生组织在第6-7片叶出现后开始分化，这意味着从营养生长向生殖生长的转变。抽薹后随着花器官的发育，通过氯化三苯基四氮唑（TTC）染色检测到正常的花粉母细胞减数分裂，但没有有活力的花粉粒。在花药发育过程中可见绒毡层退化延迟、绒毡层与中层之间的间隙以及花药退化和败育。在花发育的不同阶段有25个差异表达的MYB基因和64个与开花途径相关的基因。富集在模块22中的R2R3-MYB基因参与绒毡层和花粉的发育。共表达网络分析表明，大多数MYB基因与开花调控基因有关。MYB35、MYB26、MYB80和MMD1的表达模式可能导致绒毡层降解延迟，或花粉壁发育异常导致花粉败育。
