Department of Plant Protection, College of Food and Agricultural Sciences, Center for Chemical Ecology and Functional Genomics, Chair of Date Palm Research, King Saud University, Riyadh, Saudi Arabia.
INRAE, Sorbonne Université, CNRS, IRD, UPEC, Institute of Ecology and Environmental Sciences of Paris, iEES-Paris, Université Paris Diderot, Versailles, France.
Mol Ecol. 2021 May;30(9):2025-2039. doi: 10.1111/mec.15874. Epub 2021 Mar 22.
Palm trees are of immense economic, sociocultural, touristic, and patrimonial significance all over the world, and date palm-related knowledge, traditions, and practices are now included in UNESCOs list of the Intangible Cultural Heritage of Humanity. Of all the pests that infest these trees, the red palm weevil (RPW), Rhynchophorus ferrugineus (Olivier), is its primary enemy. The RPW is a category-1 quarantine insect pest that causes enormous economic losses in palm tree cultivation worldwide. The RPW synchronizes mass gathering on the palm tree for feeding and mating, regulated by a male-produced pheromone composed of two methyl-branched compounds, (4RS, 5RS)-4-methylnonan-5-ol (ferrugineol) and 4(RS)-methylnonan-5-one (ferrugineone). Despite the importance of odorant detection in long-range orientation towards palm trees, palm colonization, and mating, the pheromone receptor has not been identified in this species. In this study, we report the identification and characterization of the first RPW pheromone receptor, RferOR1. Using gene silencing and functional expression in Drosophila olfactory receptor neurons, we demonstrate that RferOR1 is tuned to ferrugineol and ferrugineone and binds five other structurally related molecules. We reveal the lifetime expression of RferOR1, which correlates with adult mating success irrespective of age, a factor that could explain the wide distribution and spread of this pest. As palm weevils are challenging to control based on conventional methods, elucidation of the mechanisms of pheromone detection opens new routes for mating disruption and the early detection of this pest via the development of pheromone receptor-based biosensors.
棕榈树在全世界具有巨大的经济、社会文化、旅游和遗产意义，与棕榈树相关的知识、传统和实践现在已被列入联合国教科文组织的人类非物质文化遗产名录。在所有侵害这些树木的害虫中，红棕象甲（RPW），Rhynchophorus ferrugineus（Olivier），是其主要敌人。RPW 是一种 1 类检疫性害虫，在全球范围内的棕榈树种植中造成了巨大的经济损失。RPW 通过由两种甲基支链化合物组成的雄性产生的信息素同步大量聚集在棕榈树上取食和交配，这两种化合物是（4RS，5RS）-4-甲基壬烷-5-醇（铁红醇）和 4（RS）-甲基壬烷-5-酮（铁红酮）。尽管气味检测在远距离定向到棕榈树、棕榈殖民和交配中很重要，但在该物种中尚未鉴定出信息素受体。在这项研究中，我们报告了第一个 RPW 信息素受体 RferOR1 的鉴定和特征。通过在果蝇嗅觉神经元中的基因沉默和功能表达，我们证明 RferOR1 对铁红醇和铁红酮有响应，并结合其他五种结构相关的分子。我们揭示了 RferOR1 的终生表达，这与成年交配成功率相关，而与年龄无关，这一因素可以解释这种害虫的广泛分布和传播。由于基于常规方法难以控制棕榈象甲，因此阐明信息素检测的机制为通过开发基于信息素受体的生物传感器进行交配干扰和这种害虫的早期检测开辟了新途径。
