Wright Patricia Chapple, Jimenez Beatriz Otero, Rakotonirina Paul, Andriananoely Dina H, Shea Alexandra, Ratalata Baovola, Razafimahaimodison Jean Claude
Department of Anthropology, Stony Brook University, Stony Brook, NY, United States.
Centre ValBio Research Campus, Ranomafana, Madagascar.
Front For Glob Change. 2020 Aug;3. doi: 10.3389/ffgc.2020.00091. Epub 2020 Aug 11.
Pathogens are threatening crops worldwide, but little attention has been given to the threat to tree species in undisturbed rainforest. This communication reports the first case of a tree die off caused by a "wilt" in Madagascar. In 2016 while monitoring monthly tree phenology of Ranomafana National Park (RNP), the Centre ValBio research station observed that many adult trees had brown wilted leaves. There are three species of in this rainforest, , , and , and all three have contracted this pathogen. Our goal was to document the spead of this suspected wilt in trees and determine if site, elevation and DBH had an influence on tree mortality. In 2019 we conducted an inventory of all trees in RNP and 42% of the observed trees were dead. The species with the highest mortality was , with 53% of trees dead, followed by with 18%, and with only 2% of surveyed trees dead. Bark beetle traces were observed in all dead trees. Tree death caused by this suspected fungal pathogen has spread across a major river in the area and has been found at mid and high elevations. Our results show that trees with a larger DBH have a higher mortality risk. Our report highlights the importance of fighting invasive pathogens that threaten protected ecosystems.
病原体正在威胁着全球的农作物，但对于未受干扰的雨林中树木物种所面临的威胁却很少有人关注。本通讯报道了马达加斯加首例由“枯萎病”导致树木死亡的情况。2016年，在监测拉努马法纳国家公园（RNP）树木的月度物候时，瓦尔比奥中心研究站观察到许多成年树木的叶子出现褐色枯萎现象。这片雨林中有三种[具体树种未给出英文名称]，分别是[树种一英文名称]、[树种二英文名称]和[树种三英文名称]，这三种树都感染了这种病原体。我们的目标是记录这种疑似枯萎病在[具体树种未给出英文名称]树木中的传播情况，并确定地点、海拔和胸径是否对树木死亡率有影响。2019年，我们对RNP内所有的[具体树种未给出英文名称]树木进行了清查，发现42%的被观测树木死亡。死亡率最高的树种是[树种一英文名称]，53%的树木死亡，其次是[树种二英文名称]，死亡率为18%，而[树种三英文名称]只有2%的被调查树木死亡。在所有死亡的[具体树种未给出英文名称]树木上都观察到了小蠹虫的痕迹。这种疑似真菌病原体导致的树木死亡已经蔓延到该地区的一条主要河流，并且在中高海拔地区也有发现。我们的结果表明，胸径较大的[具体树种未给出英文名称]树木死亡风险更高。我们的报告强调了对抗威胁受保护生态系统的入侵病原体的重要性。
