Autonomous selfing is altered by pollination in delayed-selfing species Gentianopsis paludosa (Gentianaceae)

• Published in: Revista brasileira de botânica 2022-12, Vol.45 (4), p.1319-1326
• Main Authors: Hou, Qinzheng, Zhao, Xiang, Duan, Meiling, Zhang, Yiping
• Format: Article
• Language: English
• Subjects: Artificial pollination; Biomedical and Life Sciences; Botany; Flowers; Gentianaceae; Gentianopsis paludosa; Life Sciences; Longevity; Plant reproduction; Plant reproductive structures; Plant Systematics/Taxonomy/Biogeography; Pollen; Pollination; Reduction; Reproduction; Reproductive Biology - Original Article; Seed set; Stamens; Stigmas (botany); Viability
• ISSN: 1806-9959; 0100-8404; 1806-9959
• DOI: 10.1007/s40415-022-00848-7

Delayed selfing, promoted by reduction in herkogamy has been widely reported as a reproductive assurance mechanism. However, the effect of pollination on the delayed-selfing mode has received less attention. Gentianopsis paludosa (Gentianaceae) has an obvious delayed-selfing mode on the northeast of Qinghai–Tibetan Plateau. In this study, we monitored effects of hand pollination on changes in herkogamy (distance from stigma to anther), pollen viability and stigma receptivity. Furthermore, we examined flower longevity and seed set under different treatments to assess the effect of pollination on reproduction. The results showed that hand pollination significantly shortened the flower longevity of G. paludosa , thereby stimulating rapid growth of stamens to ensure the completion of male function (pollen removal). The rapid growth of stamens leads to a significant reduction in herkogamy, thus shortening the time for autonomous self-pollination. However, G. paludosa showed the typical delayed-selfing mode after artificial pollination, because the flower longevity and selfing time were shortened simultaneously. In addition, pollination reduces the interference to outcrossing pollen by inhibiting the viability of selfing pollen. Meanwhile, reducing the selfing pollen viability can also allocate limited resources to ovule and seed development to improve reproduction. Therefore, we concluded that the G. paludosa can adapt to a changing pollination environment by controlling the development of internal flower organs and adjusting the time of delayed selfing. Also, this study supported the hypothesis that delayed selfing might be evolutionarily stable at a local scale.