Treating rice (Oryza sativa) with atmospheric cold plasma alters plant traits and negatively affects the growth and development of fall armyworm, Spodoptera frugiperda (Lepidoptera: Noctuidae)

Cold plasma is a non- thermal technology considered to be eco- friendly and is extensively used in sterilization purposes. Although cold plasma has been found to break seed dormancy, the potential of cold plasma against insect herbivory remains under-explored. However, it is plausible that cold plasma can have differential effects against insect herbivores, given that it produces reactive oxygen and nitrogen species (RONS) that can activate defense signalling. To test this, we evaluated the effectiveness of cold plasma on a polyphagous lepidopteran pest, fall armyworm (FAW) [Spodoptera frugiperda (Lepidoptera: Noctuidae)] on rice (Oryza sativa L.). We treated rice seeds from two commonly grown cultivars (Jewel and Diamond) with cold plasma, followed by irrigation with plasma activated water (PAW). To understand the possible implication of a direct exposure of cold plasma on herbivore growth and development, we then independently tested FAW growth on artificial diet partially made with PAW. Our results show that cold plasma significantly affected feeding, growth, and development of FAW, irrespective of the varieties. However, the effects of cold plasma on rice growth and development was variety dependent. Collectively, these findings offer significant evidence on the potential of cold plasma as a novel component for sustainable pest management.