Spodoptera frugiperda, the fall armyworm (FAW), is a lepidopteran pest that causes devastating economic losses worldwide on a wide range of crops. FAW was first discovered in Australia in 2020 after spreading from the Americas to Africa in 2016. Several approaches to control crop infestations by lepidopteran pests, including FAW, are commercially available with conventional chemical insecticides the most widely used. Unfortunately, the long-term reliance on these insecticides has led to the development of resistant insect populations and negative environmental impacts. Effective crop protection strategies with new modes of action, safer for the environment and for human health, must be developed to mitigate against insect resistance. RNA interference (RNAi) can be considered as a viable alternative to chemical insecticides. RNAi represents an environmentally friendly pest management strategy due to its RNA sequence-specific mechanism of action. Recently, the development of transgenic crops expressing dsRNA specifically targeting essential genes of insect pests, known as trans-kingdom RNAi (TK-RNAi), has emerged as a promising technology for insect control. While RNAi is effective with insect pests such as Coleopterans, Lepidopteran insects are notoriously difficult to control with RNAi initiated by ingested dsRNA, requiring effective delivery of intact dsRNA at relatively high doses. In our work, we describe new ways of plant-based dsRNA delivery to lepidopteran insect pests including FAW and the cotton bollworm, Helicoverpa armigera.