Abstract

The insect-pathogenic fungus Beauveria bassiana (Bb) colonizes several plant species as an endophyte. However, the diversity of plants colonized and the extent of colonization by this fungus have not been summarized comprehensively across all plant species. To fill this knowledge gap, a meta-analysis of published studies (years 2002–2018) on the percentage of B. bassiana plant colonization across the plant kingdom was conducted. We collected 232 published papers from which 1,051 studies (individual treatments) were extracted and analyzed with Comprehensive Meta-Analysis, Version 3 (CMA) software. Factors (n = 26) influencing plant colonization by B. bassiana were identified. Across all studies, the mean endophytic colonization of B. bassiana was 29% in different plant taxa. Plant colonization by B. bassiana was highest for isolates collected from insects. Most studies applied B. bassiana at 1 × 10⁸ conidia/ml; however, plant colonization was greatest with an application rate of 1 × 10¹² conidia/ml. Among all plant hosts, colonization percentage was highest in faba bean, plants in the family Brassicaceae, angiosperms (eudicots, annuals), plants classified with a forb/herb/vine growth habit, and plants with fibrous or tap root systems. As an inoculant, B. bassiana was most frequently applied to the whole plant after true leaves had developed. The foliar spray was the most studied inoculation method, but the application of solid grain substrate to foliage gave higher plant colonization. Studies conducted in controlled environments resulted in higher endophytic colonization with B. bassiana than field studies. Endophytic B. bassiana presence was confirmed primarily with microscopy, rather than molecular methods. High heterogeneity (I² = 97%) across studies was identified with large variability in endophytic B. bassiana colonization across a diversity of plant species. These findings increase our understanding and knowledge of the endophytic lifestyle of B. bassiana, which will facilitate the development of novel, sustainable, and eco-friendly disease management strategies with B. bassiana.

摘要

昆虫病原真菌Beauveria bassiana (Bb) 作为内生菌在几种植物物种中定殖。然而，尚未对所有植物物种的定植植物的多样性和这种真菌定植的程度进行全面总结。为了填补这一知识空白，对已发表的研究（2002-2018 年）关于B. bassiana植物在整个植物界的定殖百分比进行了荟萃分析。我们收集了 232 篇已发表的论文，从中提取了 1,051 项研究（单个治疗）并使用综合 Meta 分析第 3 版 (CMA) 软件进行了分析。确定了影响B. bassiana 植物定殖的因素 ( n = 26) 。在所有研究中，平均内生定植B. bassiana在不同的植物类群中占 29%。B. bassiana的植物定殖对于从昆虫收集的分离物最高。大多数研究以 1 × 10 ⁸分生孢子/ml应用B. bassiana ；^{然而，以 1 × 10 12}分生孢子/ml的施用率为植物定殖最大。在所有植物宿主中，蚕豆、十字花科植物、被子植物（真双子叶植物、一年生植物）、具有杂草/草本/藤本植物生长习性的植物以及具有纤维或直根系统的植物的定殖百分比最高。作为接种剂，B. bassiana在真叶发育后最常用于全株。叶面喷雾是研究最多的接种方法，但将固体颗粒基质施用于叶面会产生更高的植物定植率。在受控环境中进行的研究导致B. bassiana的内生定植比实地研究更高。内生B. bassiana的存在主要通过显微镜而不是分子方法来确认。跨研究的高异质性 ( I ^{2 = 97%) 被确定为内生}B. bassiana在多种植物物种中定殖的巨大变异性。这些发现增加了我们对B. bassiana内生生活方式的理解和认识，这将促进与B. bassiana一起开发新颖、可持续和环保的疾病管理策略。