ABSTRACT
The biotic stresses of crops pose a threat to food security and natural resources. Several environmentally friendly and sustainable strategies are needed, including the utilization of small RNAs (sRNA) in crop protection. sRNAs are imperative in mediating several developmental roles in the plant system. The various classes of sRNA—small-interfering RNA, microRNAs (miRNAs), natural antisense transcript-derived siRNAs, heterochromatic siRNAs and long siRNAs—are involved in regulating eukaryotic gene expression. Plants induce effector-triggered immunity (ETI) in order to fight pathogenic effector proteins. The ETI response is strictly controlled by siRNAs and miRNAs because ETI is much more persistent. siRNA fine-tunes the essential genes associated with hormone synthesis and signal transduction pathways involved in plant defense. sRNAs are notably very important in cases of viral infections since viruses are obligate parasites and most of them are systemic in nature. Several research groups have demonstrated the role of sRNAs as a major factor in disease outcome during host–virus interaction. Biotechnological applications have explored the possibility of using artificial miRNA to impart virus resistance. Every sRNA serves a different purpose within plant immune reactions. Therefore, the functionality of much more sRNAs needs to be researched to manage the host plant’s immunity.
