Tuning Beforehand: A Foresight on RNA Interference (RNAi) and In Vitro-Derived dsRNAs to Enhance Crop Resilience to Biotic and Abiotic Stresses

Abstract

Crop yield is severely affected by biotic and abiotic stresses. Plants adapt to these stresses mainly through gene expression reprogramming at the transcriptional and post-transcriptional levels. Recently, the exogenous application of double-stranded RNAs (dsRNAs) and RNA interference (RNAi) technology has emerged as a sustainable and publicly acceptable alternative to genetic transformation, hence, small RNAs (micro-RNAs and small interfering RNAs) have an important role in combating biotic and abiotic stresses in plants. RNAi limits the transcript level by either suppressing transcription (transcriptional gene silencing) or activating sequence-specific RNA degradation (post-transcriptional gene silencing). Using RNAi tools and their respective targets in abiotic stress responses in many crops is well documented. Many miRNAs families are reported in plant tolerance response or adaptation to drought, salinity, and temperature stresses. In biotic stress, the spray-induced gene silencing (SIGS) provides an intelligent method of using dsRNA as a trigger to silence target genes in pests and pathogens without producing side effects such as those caused by chemical pesticides. In this review, we focus on the potential of SIGS as the most recent application of RNAi in agriculture and point out the trends, challenges, and risks of production technologies. Additionally, we provide insights into the potential applications of exogenous RNAi against biotic stresses. We also review the current status of RNAi/miRNA tools and their respective targets on abiotic stress and the most common responsive miRNA families triggered by stress conditions in different crop species.

Plants’ Response Mechanisms to Salinity Stress

“…Small-RNA-mediated (micro-RNAs and small interfering RNAs) gene silencing and RNA interference (RNAi) technology has become a widely accepted method that enables a precise and multiplex editing of target genes without affecting the expression of other genes. RNAi can function as a master regulator by suppressing the transcription or mediating post-transcriptional gene silencing, thereby playing a vital role in combating biotic and abiotic stresses [ 168 , 169 , 170 ]. The development of computational tools and databases ease the identification of stress-responsive miRNAs and their targets regarding improved salt tolerance.…”

Advances and Challenges in RNA Interference Technology for Citrus Huanglongbing Vector Control

“…The dsRNA characteristics and delivery methods as well as the developmental stage of the insect treated with dsRNA can directly affect RNAi-mediated gene silencing. In general, hemipterans present stronger ribonuclease action at the adult stage, leading to higher dsRNA degradation and greater insect resistance when the dsRNA is delivered through oral ingestion [35,[82][83][84]. In ACP, the early developmental stages (e.g., nymphs) exhibit greater sensitivity to RNAi than the later developmental stages (e.g., adults) [41].…”

Double-stranded RNA (dsRNA) technology to control forest insect pests and fungal pathogens: challenges and opportunities

“…The latest spray-induced gene silencing technique (SIGS) of RNAi focuses on external applications of dsRNA via sparing on the plant leaves and stems of forest trees (Wang and Jin 2017 ). Potentially, SIGS is considered an elegant key to controlling forest pests and pathogens as well as concerns genetically modified (GM) organisms and off-target effects of pesticide application (Abdellatef et al 2021 ). The targeted fungi and insects consume the sprayed dsRNA and eventually process it using their own RNAi mechanism to initiate the silencing of the target gene.…”