Lin Shang-Yang, Di Giusto Bruno, Bain Anthony
Institute of Ecology and Evolutionary Biology, National Taiwan University, Taipei, Taiwan.
Research Center of Sleep Medicine, Taipei Medical University, Taipei, Taiwan.
Sci Rep. 2025 Jan 14;15(1):1936. doi: 10.1038/s41598-025-86135-3.
How does the fig tree Ficus benguetensis protect its investment in the production of figs and pollinating fig wasps against parasitism from non-pollinating fig wasps? This study documents a previously overlooked defense mechanism: fig abscission-the natural shedding of the fig fruit as a defense mechanism. Our bagging experiments showed that both the absence of pollination and high parasitism levels lead to the abortion of F. benguetensis figs, with positive correlations between parasitism levels, increased abscission rates, and decreased pollinator production. Moreover, we found that high parasitism corresponds to shortened fig development periods until abscission, while medium parasitism levels result in fewer pollinators. Our findings suggest that abscission may function as a resource conservation strategy, as most of the tree's investment in the figs occurs post-pollination. This study uncovers for the first time the use of fig abscission as a unique defense against non-pollinating fig wasp parasites, broadening our understanding of plant defense mechanisms within mutualistic interactions.
菲律宾榕如何保护其在无花果和传粉榕小蜂生产上的投入，使其免受非传粉榕小蜂的寄生？本研究记录了一种此前被忽视的防御机制：榕果脱落——即榕果自然脱落作为一种防御机制。我们的套袋实验表明，授粉缺失和高寄生水平都会导致菲律宾榕榕果败育，寄生水平、脱落率增加与传粉者产量减少之间呈正相关。此外，我们发现高寄生水平对应着榕果在脱落前发育周期缩短，而中等寄生水平则导致传粉者数量减少。我们的研究结果表明，脱落可能起到资源保护策略的作用，因为树木对榕果的大部分投入都发生在授粉之后。本研究首次揭示了榕果脱落作为对抗非传粉榕小蜂寄生虫的独特防御机制，拓宽了我们对互利共生相互作用中植物防御机制的理解。
