Response to fall armyworm (Spodoptera frugiperda) damage in rice (Oryza sativa) is variety and seed treatment dependent

Rice (Oryza sativa L.) is one of the most important staple food crops across the world, and in the United States, the rice industry contributes more than $34 billion to the US economy, ranking fifth in global exports. The state of Arkansas stands first in terms of rice production with 85 million cwt and is the leading exporter of rice in the United States. Among the different insect pests of rice in Arkansas, one of the emerging concerns is the Fall armyworm (Spodoptera frugiperda (J.E. Smith)). While FAW is now considered as a minor pest infesting rice- mainly in the panicle emergence stage, due to changes in climatic conditions and varying crop protection practices, there is a high probability of infestation by the FAW during the early growth stages of rice, an area less studied. To test this, we used seed-treated as well as untreated, commonly grown Arkansas rice varieties and infested them with the FAW larvae at three time points during the vegetative growth stage. We then collected data on, mass gain and developmental traits of FAW, along with damage, growth, and defense traits of the rice varieties. Our preliminary results show that the rice varieties differed in their response for FAW damage and there were also significant variety x seed treatment interactions. More detailed exploration of growth stages x variety x treatment using chemical ecology and FAW growth and development studies are in progress.