Spatial distribution pattern, bionomic, and demographic parameters of a new invasive species of armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae) in maize of South Sumatra, Indonesia

Abstract

Abstract. Hutasoit RT, Kalqutny SH, Widiarta IN. 2020. Spatial distribution pattern, bionomic, and demographic parameters of a new invasive species of armyworm Spodoptera frugiperda (Lepidoptera; Noctuidae) in maize of South Sumatra, Indonesia. Biodiversitas 21: 3576-3582. The fall armyworm, Spodoptera frugiperda, has reportedly been found in Indonesia since 2019. The main hosts of this new invading insect are food crops and several other crops. This study aimed to examine the spatial distribution pattern, bionomic, and demographic parameters for developing a sampling plan and strategy to control the pest. The study was conducted by observing the total population of S. frugiperda on nine plots of maize plants weekly. The development of S. frugiperda from egg to adult was also observed in plastic containers (diameter of 4 cm x height of 8 cm) fed with maize in controlled room conditions (temperature = 29 ± 2.1°C, 74 ± 10.1% RH). Observations were made on several bionomic and demographic parameters. The results of the study showed that the S. frugiperda distributes in groups, and each group spreads with a low grouping rate. The life cycle of S. frugiperda occurs for an average of 25.11 days with a range of 24-26 days. The net reproduction rate (Ro) of S. frugiperda was 422.46 individuals/parent/generation. S. frugiperda‘s intrinsic rate of increase was 0.22 individuals/parent/day. The length of generation (T) and S. frugiperda doubling time (DT) were 26.59 and 3.04 days, respectively. This species has survived well on the maize in the new habitat, so it will threaten the food crops, especially the maize. A sampling plan can be developed based on spatial distribution parameters to monitor population density to implement a control threshold and control measures from the early stage of maize during adult pre-emergence.

Biostatistics of fall armyworm Spodoptera frugiperda in maize plants in Bogor, West Java, Indonesia

“…because the highest mortality occurs when the population is getting older and few deaths at the beginning (Figure 8). Similarly, Hutasoit et al (2020) research states that the chance of survival of S. frugiperda decreases when it becomes the 6 th instar and pupa.…”

The endophytic fungi from South Sumatra (Indonesia) and their pathogenecity against the new invasive fall armyworm, Spodoptera frugiperda

“…Maize in Indonesia is currently facing a big problem in invasion and outbreaks of newcomer insect pests, namely the fall armyworm (Spodoptera frugiperda) (Lepidoptera: Noctuidae). S. frugiperda comes from South America (Nagoshi et al 2017;Otim et al 2018) and entered Indonesia for the first time on March 26, 2019 in West Sumatra, then in June 2019 it was found in Banten and West Java (Sartiami et al 2020) and now it has spread rapidly to various provinces in Indonesia, such as South Sumatra (Herlinda et al 2020b;Hutasoit et al 2020), Lampung (Lestari et al 2020), and Bengkulu (Ginting et al 2020). The fall armyworm has caused maize yield losses in Africa of 250-630 million US dollars per year (Bateman et al 2018).…”

Growth and Development of Fall Army Worm Spodoptera Frugiperda on Cereals

“…These observations agree with those of Maruthadurai and Ramesh (2020) on fodder maize. Hutasoit et al (2020) and observed the fecundity as 1064-1662 eggs/ female on maize. The incubation period varied significantly with cereal hosts, minimum (2.00 days) was on maize and pearl millet.…”