Special Issue: Gene Expressions in Response to Diseases, Abiotic Stresses, and Pest Damage of Horticultural Products

Horticultural crops are continuously exposed to pathogens, pests, and abiotic stress, which collectively result in significant economic losses. Over time, plants have evolved sophisticated defense mechanisms to counteract both pathogen and insect attacks, as well as to face abiotic stresses. The identification of genes involved in defense responses and stress tolerance is fundamental for selecting resistant crops, which could enable the sustainable management of diseases and damages. Gene expression is subject to complex regulation, influenced not only by developmental and tissue-specific factors, but also by both biotic and abiotic stimuli in the environment. The fluctuation in expression levels, or the gene expression profile, provides essential insights into the biological functions of genes. Comprehensive expression profiles established under various experimental conditions could facilitate the understanding of gene functions. Similarities in expression profiles between genes are an effective index for predicting gene function and mechanisms of gene expression regulation [1]. If two genes have similar expression profiles, it is reasonable to expect that they have the same biological function, even in different plant species. In addition, similar expression profiles suggest that two genes are regulated by the same mechanism (e.g., a transcription factor (TF) and a cis-element). Therefore, genes with highly similar expression profiles are likely to have the same biological functions and regulatory mechanisms. Transcriptomics enables the simultaneous analysis of gene expression in plants, pathogens, and pest interactions.