Biological Control Potential of Native Entomopathogenic Nematodes (Steinernematidae and Heterorhabditidae) against <i>Mamestra brassicae</i> L. (Lepidoptera: Noctuidae)

• Main Authors: Anna Mazurkiewicz, Dorota Tumialis, Magdalena Jakubowska
• Format: Article
• Language: English
• Published: MDPI AG 2020-09-01
• Series: Agriculture
• Subjects: bioassay; biological control; <i>Heterorhabditis megidis</i>; <i>Mamestra brassicae</i>; <i>Steinernema feltiae</i>
• Online Access: https://www.mdpi.com/2077-0472/10/9/388

The largest group of cabbage plant pests are the species in the owlet moth family (Lepidoptera: Noctuidae), the most dangerous species of which is the cabbage moth (<i>Mamestra brassicae</i> L.). In cases of heavy infestation by this insect, the surface of plants may be reduced to 30%, with a main yield loss of 10–15%. The aim of the present study was to assess the susceptibility of <i>M. brassicae</i> larvae to nine native nematode isolates of the species <i>Steinernema feltiae</i> (Filipjev) and <i>Heterorhabditis megidis</i> Poinar, Jackson and Klein under laboratory conditions. The most pathogenic strains were <i>S. feltiae</i> K11, <i>S. feltiae</i> K13, <i>S. feltiae</i> ZAG11, and <i>S. feltiae</i> ZWO21, which resulted in 100% mortality at a temperature of 22 °C and a dosage of 100 infective juveniles (IJs)/larva. The least effective was <i>H. megidis</i> Wispowo, which did not exceed 35% mortality under any experimental condition. For most strains, there were significant differences (<i>p</i> ≤ 0.05) in the mortality for dosages between 25 IJs and 50 IJs, and between 25 IJs and 100 IJs, at a temperature of 22 °C. Statistical analysis of the effect of temperature on mortality showed that only strain <i>H. megidis</i> Wipsowo exhibited significant differences (<i>p</i> ≤ 0.05) when applied at dosages of 50 IJs and 100 IJs.