LAUSR

Simple Summary The fall armyworm (FAW) (Spodoptera frugiperda J.E. Smith) is now a widespread and resident pest in Africa, where it is causing substantial yield losses to maize. Maize is an important staple food supporting more than 500 million people in sub-Saharan Africa. Since the arrival of FAW to Africa six years ago, multidisciplinary research aimed at managing the FAW and mitigating its impact on food security has been ongoing. Understanding the biology of the FAW under sub-Saharan African conditions and developing simple screening techniques for maize against the FAW will improve research outputs on FAW management. This study aimed to increase the understanding of FAW behaviour under sub-Saharan African conditions and investigated simple methods for the laboratory rearing of FAW and screening of maize. FAW was reared successfully using a natural maize-based diet and an artificial soy- and wheat flour-based diet under specified conditions. The study generated useful information on FAW developmental stages and the reaction types of maize, enabling the identification of promising maize genetics for continued breeding. The baseline information presented in this paper will allow for the controlled rearing, infestation, host screening and integration of candidate FAW-resistant genes into market-preferred maize lines in Zambia and related agroecologies. Abstract Knowledge of fall armyworm (FAW) (Spodoptera frugiperda J.E. Smith) rearing, infestation and development and precision screening protocols are preconditions for the successful introgression of resistance genes into farmer-preferred varieties. We aimed to determine FAW developmental stages, screen tropical maize and select resistant lines under controlled conditions in Zambia. Field-collected FAW samples constituting 30 egg masses and 60 larvae were reared using maize leaf- and stalk-based and soy- and wheat flour-based diets at 27 ± 1 °C, 60 ± 5% relative humidity and 12 h day length. The resulting neonates were separated into sets A and B. The life cycles of set A and field-collected larvae were monitored to document the FAW developmental features. Set B neonates were used to infest the seedlings of 63 diverse tropical maize genotypes. Egg, larva, pupa and adult stages had mean durations of 2, 24, 20 and 12 days, respectively. Test maize genotypes revealed significant differences (p < 0.05) based on FAW reaction types, with lines TL13159, TL02562, TL142151, VL050120 and CML548-B exhibiting resistance reactions, while CML545-B, CZL1310c, CZL16095, EBL169550, ZM4236 and Pool 16 displayed moderate resistance. These genotypes are candidate sources of FAW resistance for further breeding. This study will facilitate controlled FAW rearing for host screening in the integration of FAW resistance into market-preferred maize lines.