中文摘要：

内参基因的准确选择是利用实时荧光定量PCR进行准确分析基因相对表达量的前提。虫霉目真菌新蚜虫疠霉（Pandora neoaphidis）是重要蚜科专化性病原真菌，经常引发多种作物上蚜虫种群的流行病。本研究通过实时荧光定量PCR分析了新蚜虫疠霉ARSEF 5403中3个传统管家基因18SrRNA （18S）、28SrRNA（28S）和延伸因子1α相似蛋白（elongation factor-1 alpha-like protein, EF1） mRNA表达差异情况，并利用geNorm、NormFinder和BestKeeper软件综合分析了其在4个生长阶段（分生孢子、萌发管时期、短菌丝和长菌丝）和3种营养条件（GLEN培养基、OS-SDB培养基和Grace培养基）下表达的稳定性。结果表明，基于公共数据库序列设计的候选内参基因的引物具有良好的扩增效率和特异性。经geNorm软件分析，新蚜虫疠霉在不同生长阶段和不同营养条件下3个候选内参基因的平均表达稳定性（M值）分别为：18S（0.457）＞28S（0.534）＞EF1（0.749）和18S（0.389）＞28S（0.557）＞EF1（0.607）。利用NormFinder软件分析，新蚜虫疠霉不同生长阶段和不同营养条件下3个候选内参基因的平均M值分别为：18S（0.084）＞28S（0.264）＞EF1（0.509）和18S（0.118）＞28S（0.355）＞EF1（0.403）。而BestKeeper软件分析得到的稳定性等级有所差异，在不同生长阶段和不同营养条件下候选内参基因28S表达最稳定，18S次之，EF1最不稳定。综合分析3款软件对荧光定量PCR结果的稳定性等级的平均值，得出在不同生长阶段和不同营养条件下候选内参基因18S表达最为稳定。筛选出的18S可作为分析新蚜虫疠霉基因表达差异的一个较为可靠的内参基因，同时为后续研究新蚜虫疠霉的生长、毒力相关基因的表达分析研究提供技术支持。

英文摘要：

Selection of a suitable reference gene is an important prerequisite for precise gene expression analysis by Real-time quantitative PCR. Pandora neoaphidis, an obligate aphid pathogenic fungus, can induce a drastic epidemic to cause the collapse of aphid populations on crops. To determine potential reference genes for normalization of Real-time PCR data on P. neoaphidis, the transcript levels of 3 traditional housekeeping genes including 18SrRNA（18S）, 28SrRNA（28S） and elongation factor 1 alpha-like protein（EF1）, were measured in this study. We investigated the expression stability of 3 candidate reference genes in P. neoaphidis ARSEF 5403 in different developmental stages including conidia stage, germ tubes stage, early hyphae stageand elongated hyphae stage, as well as under different nutrient conditions including OS-SDB medium, GLEN medium and Grace’s insect cell culture medium. The expression stability of candidate reference genes was calculated using 3 algorithms including geNorm, NormFinder and BestKeeper. Results from Real-time PCR revealed that designed primers had a good proliferation efficiency and specificity. The analysis with geNorm algorithms revealed that the stability value （M value） of candidate reference genes was 18S（0.457）〉28S （0.534）〉EF1（0.749） under different developmental stages, and 18S（0.389）〉28S（0.557）〉EF1（0.607） under different nutrient conditions. Additionally, the analysis with NormFinder algorithms revealed that M value of candidate reference genes was 18S（0.084）〉28S（0.264）〉EF1（0.509） under different developmental stages, and 18S（0.118）〉28S（0.355）〉EF1（0.403） under different nutrient conditions. 18S was ranked as the most suitable reference gene of the 3 candidate reference genes analyzed by geNorm and NormFinder. However, the analysis with BestKeeper algorithms revealed that 28S was the most suitable reference gene under all conditions examined, followed by 18S, and EF1 was the most unstable reference gen