Fungi, algae, plants, protozoa, and bacteria are all known to form spores, especially hardy and ubiquitous propagation structures that are also often the infectious agents of diseases. Spores can survive for thousands of years, frozen in the permafrost (Kochkina et al., 2012), with the oldest viable spores extracted after 250 million years from salt crystals (Vreeland, Rosenzweig, & Powers, 2000). Their resistance to high levels of UV, desiccation, pressure, heat, and cold enables the survival of spores in the harshest conditions (Setlow, 2016). For example, Bacillus subtilis spores can survive and remain viable after experiencing conditions similar to those on Mars (Horneck et al., 2012). Spores are disseminated through environmental factors. Wind, water, or animal carriage allow spores to be spread ubiquitously throughout the environment. Spores will break dormancy and begin to germinate once exposed to favorable conditions. Germination is the mechanism that converts the spore from a dormant biological organism to one that grows vegetatively and is capable of either sexual or asexual reproduction. The process of germination has been well studied in plants, moss, bacteria, and many fungi (Hohe & Reski, 2005; Huang & Hull, 2017; Vesty et al., 2016). Unfortunately, information on the complex signaling involved in the regulation of germination, particularly in fungi remains lacking. This chapter will discuss germination of fungal spores covering our current understanding of the regulation, signaling, outcomes, and implications of germination of pathogenic fungal spores. Owing to the morphological similarities between the spore-hyphal and yeast-hyphal transition and their relevance for disease progression, relevant aspects of fungal dimorphism will be discussed alongside spore germination in this chapter.

众所周知，真菌，藻类，植物，原生动物和细菌都会形成孢子，尤其是坚硬和无处不在的繁殖结构，它们通常也是疾病的传染原。孢子可以在冻土中冷冻保存数千年（Kochkina等，2012），其中最古老的可行孢子是在2.5亿年后从盐晶体中提取的（Vreeland，Rosenzweig和Powers，2000年）。它们对高水平的紫外线，干燥，压力，热和冷的抵抗力使孢子能够在最恶劣的条件下生存（Setlow，2016年）。例如枯草芽孢杆菌孢子在经历类似于火星的条件后可以生存并保持活力（Horneck等，2012）。孢子是通过环境因素传播的。风，水或动物的运输使孢子在整个环境中无处不在。一旦暴露在有利条件下，孢子将打破休眠状态并开始发芽。萌发是将孢子从休眠的生物转化为营养生长且能够有性或无性繁殖的一种机制。发芽过程已经在植物，苔藓，细菌和许多真菌中得到了很好的研究（Hohe＆Reski，2005; Huang＆Hull，2017; Vesty et al。，2016）。不幸的是，仍然缺乏有关发芽调控特别是真菌中涉及的复杂信号传导的信息。本章将讨论真菌孢子的萌发，涵盖我们对病原性真菌孢子萌发的调控，信号转导，结果和含义的当前了解。由于孢子-菌丝和酵母-菌丝的过渡在形态上的相似性以及它们与疾病进展的相关性，本章将与孢子萌发一起讨论真菌二态性的相关方面。