Abundance and diversity of the culturable nectar mycobiome in Rhododendron catawbiense varies with elevation  

椭圆叶杜鹃花蜜可培养真菌群落丰度和多样性的海拔梯度格局

作　　者：Daniel A.Barker Ayesha Khan Ekaterina Kaverina Carlos Martel Gerardo Arceo-Gómez 

机构地区：[1]East Tennessee State University,Johnson City,TN,37614,USA [2]Royal Botanical Gardens Kew,Richmond,TW93DS,UK

出　　处：《Journal of Plant Ecology》2024年第6期184-194,共11页植物生态学报(英文版)

基　　金：funded by East Tennessee State University RDC grant and NSF DEB 1931163 to GAG,and the honors in discipline grant awarded to AK.

摘　　要：The nectar microbiome can influence pollinator choice and plant fitness.Previous research has shown that changes in environmental conditions at large spatial scales can influence nectar microbiome composition.However,little is known about how changes in climate with increasing elevation affect nectar microbiome abundance and composition.Here,we describe the culturable nectar mycobiome(CNMB)of Rhododendron catawbiense(Ericaceae)by quantifying colony abundance,identity and richness of fungal genera.We further evaluate how the CNMB abundance,diversity and composition(i.e.the fungal species within the nectar microbiome)varies at two different elevations.Nectar samples were collected from R.catawbiense individuals at a high and low elevation and were cultured on yeast agar with 0.01%chloramphenicol media.Fungal colonies were categorized morphologically,quantified and then identified using DNA barcoding.In total,2822 fungal colonies were recorded belonging to six genera across both elevations.Elevation did not influence CNMB diversity(Simpson’s diversity index)or genera richness per flower,however only three genera were found at the high elevation while six were found at the low elevation.Elevation had a significant effect on colony abundance with a 95%increase in the number of colonies in nectar samples at low compared with the high elevation.Variation in abundance and the overall genera composition of fungal colonies across elevations may have the potential to affect nectar quantity and quality and ultimately pollination success.This study adds to our understanding of the drivers of CNMB composition across spatial scales and its potential implications for plant-pollinator interactions.花蜜微生物群落会影响传粉者的选择和植物的适应性。以往的研究表明,环境条件的变化能够影响花蜜微生物群落组成。然而,学术界尚不清楚对于随海拔升高而引起的气候变化如何影响花蜜微生物群落的丰度和多样性。本研究通过量化真菌属的菌落丰度、种类和丰富度,描述了椭圆叶杜鹃(Rhododendron catawbiense)花蜜中的可培养真菌群落。此外,该研究还评估了花蜜中的可培养真菌群落(culturable nectar mycobiome,CNMB)的丰度、多样性以及组成(即花蜜微生物群落中的真菌种类)在不同海拔高度下的变化。我们从高海拔和低海拔的椭圆叶杜鹃个体中采集了花蜜样本,并在含有0.01%氯霉素的酵母培养基上进行培养。对真菌菌落进行形态分类和计数,并通过DNA条形码进行鉴定。总共记录了来自两个海拔高度的2822个真菌菌落,分别属于6个属。海拔对CNMB多样性(Simpson’s多样性指数)或每朵花的属丰富度没有显著影响,但在高海拔仅发现3个属,而在低海拔则发现6个属。海拔显著影响了菌落的丰度,低海拔的花蜜样本中的菌落数量比高海拔增加了95%。不同海拔高度下真菌菌落的丰度和整体属组成的变化,可能会对花蜜的数量和质量以及传粉成功率产生影响。上述结果加深了学术界对CNMB组成驱动因素及其对植物-传粉者相互作用影响的认识。

关 键 词：NECTAR DIVERSITY mycobiome Rhododendron catawbiense POLLINATION elevation gradient 

分 类 号：Q94[生物学—植物学]