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Miscanthus Feeding Insects and Nematodes
8.3.2.3 Damage
Larvae cause damage on the leaves when they hatch by consuming foliage.
Young larvae initially consume leaf tissue from one side, leaving the opposite
epidermal layer intact. The older larvae begin to make holes in leaves and
eat from the edge of the leaves inward. Feeding in the whorl of corn often
produces a characteristic row of perforations in the leaves.
Fall armyworm S. frugiperda was found to infest the whorls of M. × giganteus
in field plots (Prasifka et al., 2009). Greenhouse study using fall armyworm
population collected in the field from natural infestation indicated that both
corn and rice strains of S. frugiperda are able to develop and reproduce on
Miscanthus along with other hosts, including corn. In this experiment fall
armyworm evidently preferred corn to Miscanthus; however, relative survival of rice strain fall armyworm was greater on Miscanthus. Thus, this dangerous pest can infest the biomass and food/feed crop (Prasifka et al., 2009).
Stefanovska et al. (2017b) observed two Noctuidae species in M. × giganteus:
Turnip Moth Scotia segetum L. and Silver Y-Moth Autografa gamma L., feeding
on planting at first year of vegetation (Figure 8.2); however, no conspicuous
symptoms were found.
8.3.3 Generalist Coleopteran
The Western corn rootworm Diabrotica virgifera virgifera Le Conte is a native
to North America, where it is considered as the main pest of corn (Yu et al.,
2019). The pest is present in many European countries, spreading constantly
year by year (Toth et al., 2020). Corn is the only crop in which high population
densities can develop.
8.3.3.1 Identification
The adults, 5–6 mm long, are dark yellow in color and there are three black
stripes on the wing covers. Newly hatched larvae are nearly colorless, but
gradually turn white as they feed and get older. Mature larvae reach about
13 mm long, and are creamy, white with a brown head capsule.
8.3.3.2 Life Cycle
Western corn rootworms produce one generation per year (Chiang, 1973).
The pest overwinters in the soil in egg stage. The larvae hatch from eggs
from late spring to early summer. The larvae move around in the soil, feeding on the maize roots. Their development lasts approximately 1 month.
Larvae pupate in the soil and emerge as adults in 5–10 days. Adults emerge
throughout the summer period and can mate several times. Females lay eggs
in small clutches near the base of corn stalks, where they remain unhatched
for the winter (Gray et al., 2009).
Miscanthus Feeding Insects and Nematodes
8.3.2.3 Damage
Larvae cause damage on the leaves when they hatch by consuming foliage.
Young larvae initially consume leaf tissue from one side, leaving the opposite
epidermal layer intact. The older larvae begin to make holes in leaves and
eat from the edge of the leaves inward. Feeding in the whorl of corn often
produces a characteristic row of perforations in the leaves.
Fall armyworm S. frugiperda was found to infest the whorls of M. × giganteus
in field plots (Prasifka et al., 2009). Greenhouse study using fall armyworm
population collected in the field from natural infestation indicated that both
corn and rice strains of S. frugiperda are able to develop and reproduce on
Miscanthus along with other hosts, including corn. In this experiment fall
armyworm evidently preferred corn to Miscanthus; however, relative survival of rice strain fall armyworm was greater on Miscanthus. Thus, this dangerous pest can infest the biomass and food/feed crop (Prasifka et al., 2009).
Stefanovska et al. (2017b) observed two Noctuidae species in M. × giganteus:
Turnip Moth Scotia segetum L. and Silver Y-Moth Autografa gamma L., feeding
on planting at first year of vegetation (Figure 8.2); however, no conspicuous
symptoms were found.
8.3.3 Generalist Coleopteran
The Western corn rootworm Diabrotica virgifera virgifera Le Conte is a native
to North America, where it is considered as the main pest of corn (Yu et al.,
2019). The pest is present in many European countries, spreading constantly
year by year (Toth et al., 2020). Corn is the only crop in which high population
densities can develop.
8.3.3.1 Identification
The adults, 5–6 mm long, are dark yellow in color and there are three black
stripes on the wing covers. Newly hatched larvae are nearly colorless, but
gradually turn white as they feed and get older. Mature larvae reach about
13 mm long, and are creamy, white with a brown head capsule.
8.3.3.2 Life Cycle
Western corn rootworms produce one generation per year (Chiang, 1973).
The pest overwinters in the soil in egg stage. The larvae hatch from eggs
from late spring to early summer. The larvae move around in the soil, feeding on the maize roots. Their development lasts approximately 1 month.
Larvae pupate in the soil and emerge as adults in 5–10 days. Adults emerge
throughout the summer period and can mate several times. Females lay eggs
in small clutches near the base of corn stalks, where they remain unhatched
for the winter (Gray et al., 2009).