Leaf senescence is an important developmental process for the plant life cycle. It is controlled by endogenous and environmental factors and can be positively or negatively affected by plant growth regulators. It is characterised by major and significant changes in the patterns of gene expression. Auxin, especially indole-3-acetic acid (IAA), is a plant growth hormone that affects plant growth and development. The effect of IAA on leaf senescence is still unclear. In this study, we performed microarray analysis to investigate the role of IAA on gene expression during senescence in Arabidopsis thaliana. We sprayed IAA on plants at 3 different time points (27, 31 or 35 days after sowing). Following spraying, PSII activity of the eighth leaf was evaluated daily by measurement of chlorophyll fluorescence parameters. Our results show that PSII activity decreased following IAA application and the IAA treatment triggered different gene expression responses in leaves of different ages.

中文翻译：

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吲哚-3-乙酸（IAA）对拟南芥叶片衰老过程中基因表达的影响分析

叶片衰老是植物生命周期的重要发育过程。它受内源性和环境因素控制，并可能受到植物生长调节剂的正面或负面影响。它的特征是基因表达模式的重大变化。生长素，特别是吲哚-3-乙酸（IAA）是一种影响植物生长发育的植物生长激素。IAA对叶片衰老的影响仍不清楚。在这项研究中，我们进行了微阵列分析，以研究IAA对拟南芥衰老过程中基因表达的作用。。我们在3个不同的时间点（播种后27、31或35天）向植物喷洒IAA。喷雾后，每天通过测量叶绿素荧光参数评估第八片叶子的PSII活性。我们的结果表明，施用IAA后PSII活性下降，并且IAA处理在不同年龄的叶片中引发了不同的基因表达响应。