Draga Samela, Palumbo Fabio, Riommi Damiano, Mendes Marta Adelina, Cavalleri Alex, Gabelli Giovanni, Farinati Silvia, Vannozzi Alessandro, Barcaccia Gianni
Department of Agronomy, Food, Natural Resources, Animals and Environment, University of Padova, 35020, Legnaro, PD, Italy.
Department of Biosciences, Università Degli Studi Di Milano, Via Celoria 26, 20133, Milan, Italy.
Plant Cell Rep. 2025 Jun 25;44(7):156. doi: 10.1007/s00299-025-03546-2.
Cytological and molecular investigations in chicory revealed crucial aspects related to female gametophyte development, pollen‒stigma interactions, and self-incompatibility responses. The Asteraceae family, one of the largest of angiosperms, comprises approximately 24,000 species and exhibits considerable variation in reproductive biology. Cichorium intybus (commonly known as chicory) is among the most well-known and widespread species of the family. In addition to its economic and commercial value, chicory is considered one of the most interesting species in its family for the study of sporophytic self-incompatibility (SSI). Information regarding megasporogenesis, megagametogenesis, pollen tube development, and embryogenesis in this species is almost entirely absent in the scientific literature. Using confocal laser scanning microscopy (CLSM), we conducted a detailed investigation of female gametophyte development, providing a comprehensive characterization of the cytological stages involved in megasporogenesis and megagametogenesis. To investigate the dynamics and timing of pollen tube development and pollen rejection, we microscopically examined the interactions between pollen and stigmas in both cross- and self-pollinated plants. The response was similar to those documented in other Asteraceae species with a 'semidry' type of stigma. Integrated RNA-seq analyses further highlighted transcriptional changes during self- and non-self-pollen recognition and led to the identification of potential candidate genes involved in pollen tube development and callose deposition (in the case of self-incompatibility reactions). In parallel, for the first time, we characterized both the embryogenesis process and embryo sac degeneration in a compatible and incompatible crosses, respectively.
对菊苣的细胞学和分子研究揭示了与雌配子体发育、花粉-柱头相互作用以及自交不亲和反应相关的关键方面。菊科是被子植物中最大的科之一，约有24000个物种，其生殖生物学表现出相当大的差异。菊苣是该科中最著名且分布最广的物种之一。除了具有经济和商业价值外，菊苣还被认为是研究孢子体自交不亲和（SSI）的该科中最有趣的物种之一。关于该物种的大孢子发生、雌配子体发生、花粉管发育和胚胎发生的信息在科学文献中几乎完全缺失。利用共聚焦激光扫描显微镜（CLSM），我们对雌配子体发育进行了详细研究，全面描述了大孢子发生和雌配子体发生所涉及的细胞学阶段。为了研究花粉管发育和花粉排斥的动态过程和时间，我们在显微镜下检查了异花授粉和自花授粉植物中花粉与柱头之间的相互作用。其反应与其他具有“半干”型柱头的菊科物种所记录的反应相似。综合RNA测序分析进一步突出了自花和非自花花粉识别过程中的转录变化，并鉴定出了参与花粉管发育和胼胝质沉积（在自交不亲和反应中）的潜在候选基因。同时，我们首次分别对亲和杂交和不亲和杂交中的胚胎发生过程和胚囊退化进行了表征。
