中国植物丛枝菌根侵染特征研究

Colonization characteristics of arbuscular mycorrhizal fungi in plants distributed in China

摘要:

丛枝菌根真菌在生态系统和植物生长过程中发挥着重要作用，目前对其生理生态功能的研究备受关注，但主要集中在丛枝菌根真菌对植物促生作用方面。植物的菌根侵染特征是表征真菌与植物共生紧密程度的重要标志，也是评价植物生态适应性的关键指标，然而针对我国植物丛枝菌根发育特征及其分布特点的系统性研究尚属空白。【目的】探究我国植物丛枝菌根真菌的侵染特征，及其在不同生态系统和气候区域中的分布规律，为推动丛枝菌根研究的发展提供基础数据。【方法】利用全球植物菌根数据库“FungalRoot”和605篇中文文献的植物菌根侵染特征数据，并补充生态系统、气候区域、植物类型和植物生长年限等共47 700组数据，建立了中国植物丛枝菌根侵染信息数据库，并以此为基础进行研究。【结果】我国植物丛枝菌根真菌侵染率在0-55%占69.7%，55%-100%占30.3%，绝大多数植物丛枝菌根真菌侵染强度、菌丝丰度、泡囊丰度和丛枝丰度均分布在40.0%以下。丛枝菌根共生形态中，A型占比最大，为56.3%。农田、荒漠、草地生态系统的植物丛枝菌根真菌侵染率相近，分别为51.8%、51.6%、51.8%，而森林生态系统的侵染率较低，为40.4%。荒漠生态系统植物的丛枝菌根真菌侵染强度、菌丝丰度、泡囊丰度和丛枝丰度最高，分别达到46.0%、47.1%、37.2%和31.2%。根据气候区域，植物的侵染水平由高到低排序为暖温带(53.3%)>热带(50.0%)>中温带(45.2%)>亚热带(42.2%)。草本植物的侵染水平高于木本植物，多年生植物高于一年生植物。木本植物中，灌木的侵染率水平最高，为46.3%，其次是乔木和藤本植物，均为43.9%。草本植物在侵染强度和菌丝丰度上高于木本植物，分别为30.2%和32.5%，而木本植物在泡囊和丛枝丰度方面具有优势，分别为19.5%和23.4%。我国丛枝菌根植物中，被子植物占据绝大多数，共有110科，占比达到90.2%，蕨类、裸子、石松门植物较少。【结论】我国大部分植物丛枝菌根真菌侵染率在55%以下，侵染特征等指标分布在40.0%以下；同时，不同生态系统、气候区域、植物类型和生长年限均会对侵染特征产生不同程度的影响。

关键词:丛枝菌根;侵染特征;植物类型;生态系统;气候区域

Abstract:

Arbuscular mycorrhizal fungi play important roles in ecosystems and plant growth. The physiological and ecological roles of arbuscular mycorrhizal fungi, especially in promoting plant growth, have attracted much attention. The colonization characteristics of arbuscular mycorrhizal fungi, as vital indicators of the symbiotic relationship between arbuscular mycorrhizal fungi and plants, are key parameters to evaluate the ecological adaptability of plants. However, systematic and comprehensive studies remain to be carried out regarding the colonization characteristics of arbuscular mycorrhizal fungi in the plants growing in China. [Objective] This study explored the colonization parameters of arbuscular mycorrhizal fungi in the plants growing in China, as well as their distribution in different ecosystems and climate regions, aiming to provide fundamental data to advance the research on mycorrhizae. [Methods] A database of arbuscular mycorrhizal fungi colonizing plants growing in China was established with the data from FungalRoot and 605 Chinese papers. Furthermore, the database was supplemented with 47 700 data sets including mycorrhizal colonization characteristics, ecosystem types, climate regions, plant types, and plant growth years. The analysis in this study was then performed based on this database. [Results] In China, 69.7% and 30.3% plants exhibited the arbuscular mycorrhizal fungal colonization rates ranging from 0 to 55% and from 55% to 100%, respectively. The majority of plants showed the arbuscular mycorrhizal fungal colonization intensity, hyphal abundance, vesicular abundance, and arbuscular abundance below 40.0%. Among the symbiotic forms of arbuscular mycorrhizal fungi, type A was the most prevalent, existing in 56.3% plants. Arbuscular mycorrhizal fungi demonstrated similar colonization rates in farmland, desert, and grassland ecosystems (51.8%, 51.6%, and 51.8%, respectively) and a low colonization rate (40.4%) in forest ecosystems. The plants in desert ecosystems showcased the highest arbuscular mycorrhizal fungal colonization intensity, hyphal abundance, vesicular abundance, and arbuscular abundance, which reached 46.0%, 47.1%, 37.2%, and 31.2%, respectively. In different climate regions, the colonization level followed the trend of warm temperate zone (53.3%)>tropical zone (50.0%)>temperate zone (45.2%)>subtropical zone (42.2%). The colonization level was higher in herbaceous plants than in woody plants, and higher in perennial plants than in annual plants. Among woody plants, shrubs had the highest colonization rate at 46.3%, followed by trees and vines, both at 43.9%. Herbaceous plants had higher colonization intensity (30.2%) and hyphal abundance (32.5%) than woody plants, while woody plants had higher vesicular abundance (19.5%) and arbuscular abundance (23.4%). Among the plants colonized by arbuscular mycorrhizal fungi, angiosperms accounted for the majority (90.2%, belonging to 110 families), while ferns, gymnosperms, and lycophytes were less common. [Conclusion] In China, arbuscular mycorrhizal fungi showed the colonization rate below 55% and colonization indicators below 40.0% in most plants. Different ecosystems, climate regions, plant types, and plant growth years affected the colonization status to different degrees.

Key words:arbuscular mycorrhizas;colonization characteristics;plant type;ecosystem;climate region