Host‐Induced Gene Silencing for Pest/Pathogen Control

Abstract

Host‐induced gene silencing (HIGS) is an approach that shows promise for the control of a variety of problematic crop‐damaging organisms, ranging from nematodes and insects, to fungi and parasitic plants. In general, HIGS utilises ribonucleic acid interference (RNAi) molecules produced by the plant, which then target key genes in pests/pathogens, ideally leading to improved resistance of the plant and a reduction in damage. As this area of research is still very much in development, the possible off‐target and nontarget effects need to be assessed, as do the long‐term stability and effectiveness. Practical implementation of HIGS to commercial crop production will rely on extensive field‐testing, as well as regulatory and marketplace acceptance of new varieties. Key Concepts Plants are susceptible to damage from a variety of biological agents, including insect pests, and from pathogens, such as various species of fungi, nematodes and viruses. Damage to crops by biological sources causes significant losses to yield. Silencing of key pest and pathogen genes is a possible strategy for reducing crop damage and can be accomplished by RNA molecules expressed by the host plant. Genetic constructs designed to silence pest and pathogen genes can be stably inserted into the host plant genome through a variety of methods, such as particle bombardment or Agrobacterium ‐mediated transformation. An alternate method for silencing genes consists of the direct application of purified RNA molecules to the plant itself.