Influence of Host Plant Species and Fertilization Regime on Larval Performance and Feeding Preference of the Redbacked Cutworm and the Pale Western Cutworm (Lepidoptera: Noctuidae)

Abstract

The redbacked cutworm, Euxoa ochrogaster (Guenée), and the pale western cutworm, Agrotis orthogonia (Morrison), are generalist pests that cause sporadic economic damage to several annual crops in the Canadian Prairies. Early larval instars feed on foliage, whereas mature larvae eat into the stem and sever crop seedlings. Here, we evaluate the influence of annual crop species and host fertilization on the larval performance and feeding preference of both cutworm species. Performance is the ability of an insect to reach its maximum growth potential. The first set of experiments evaluated larval development and preference on canola (Brassica napus L. [Capparales: Brassicaeae]), field peas (Pisum sativa L. [Fabales: Fabaceae]), and spring wheat (Triticum aestivum L. [Cyperales: Poaceae]). The redbacked cutworm had higher performance on canola and peas, while the pale western cutworm had higher performance on wheat. In multiple-choice feeding experiments, the redbacked cutworm consumed more canola, whereas the pale western cutworm consumed more spring wheat. The third set of experiments evaluated larval development on fertilized and unfertilized seedlings of canola and spring wheat seedlings. When fed unfertilized seedlings, the redbacked cutworm had better performance on canola than spring wheat, whereas pale western cutworm had better performance on spring wheat than canola. Fertilizer application enhanced the performance of both cutworms regardless of the crop species. Despite their generalist feeding behavior, both cutworm species have a larval feeding preference for the host plant on which they achieve high performance. Canola-cereal cropping is a common crop rotation schedule in the region; however, this tactic will not negatively impact cutworm performance.

Effects of larval host and natural microsporidian infection on adult life history traits of the forest tent caterpillar (Lepidoptera: Lasiocampidae)

“…Moreover, FTC reared on an artificial diet developed larger wings compared to maple foliage-fed moths in the 2018 experiment. Artificial diets are usually considered nutritionally superior to fresh foliage, as they are formulated to offer optimal nutritional value to insects, as reported across several laboratory studies on Lepidoptera (Gupta et al 2005, Batallas and Evenden 2019). Foliage contains non-digestible compounds and secondary metabolites, which can negatively affect nutrient uptake by the insect and could explain our 2014 results.…”

Fermented or Floral? Developing a Generalized Food Bait Lure to Monitor Cutworm and Armyworm Moths (Lepidoptera: Noctuidae) in Field Crops

“…The sex and feeding status (starved or fed) of moths served as physiological treatments. Redbacked cutworm moths were obtained from a laboratory colony maintained on a pinto-based meridic diet [ 49 ] under controlled conditions in growth chambers (Intellus Environmental Controller, Percival Scientific, Perry, IA, USA) at 21 °C and a photoperiod of 16:8 (light: dark). Recently enclosed moths were housed individually in 1000 mL plastic containers with either water or 10% sugar solution.…”