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Miscanthus Feeding Insects and Nematodes
of three pairs of leaves. Besides direct damage, yellow sugarcane aphid also
transmits sugarcane mosaic potyvirus (Blackman & Eastop, 2000).
The S. flava was first recorded on M. × giganteus in 2008 in leaf damage
collected from seven locations of Indiana, Illinois, Nebraska, Kentucky, and
Iowa (Bradshaw et al., 2010). Aphids were found on young to old plantings
(1–21 year) in large populations. Aphids feeding leads to leaf death. The
symptoms of M. × giganteus infestations, specifically yellowing and redding
of leaves, were very similar to sugarcane (Nuessly & Hentz, 2002) and sorghum (Costa-Arbulú et al., 2001). The S. flava damage has economic importance as a key factor of M. × giganteus plantation establishment during the
first year of vegetation.
Corn leaf aphid Rhopalosiphum maidis L. (Homoptera: Aphidiidae) is native
to Asia, although they have spread almost worldwide. It occurs sporadically
in cool temperature climate (Blackman & Eastop, 2000). In several countries it
is considered as an economically important pest of Poaceae (Gramineae) monocot crops, namely, wheat, barley, sorghum, and M. sinensis (Carena & Glogoza,
2004; Huggett et al., 1999). This damage potential is especially concerning
because most plant viruses are transmitted by aphids (Hull, 2002) and R. maidis
can transmit the RPV strain (cereal yellow dwarf virus) of barley yellow dwarf
luteovirus (BYDV) to M. × giganteus (Huggett et al., 1999; Jarošová et al., 2013).
8.2.2.4 Identification
The wingless corn leaf aphid is oval, about 2 mm, blue-green in color with
black antennae, legs, and tailpipes. The body and legs are black. The nymphs
are similar to adults with smaller size and underdeveloped antennae and
tailpipes. The winged form of the aphid is about the same size as the wingless ones, with dark green to black body and black tailpipes.
8.2.2.5 Life Cycle
The species reproduce via parthenogenesis. It overwinters in both eggs and
females (in warmer climates) on cereal grasses. The optimum temperature
for development is around 30°C. Corn leaf aphids live in large colonies on
their host plants.
8.2.2.6 Damage
The corn leaf aphids feed by removing plant sap from the phloem. The typical signs of feeding while insect in high population are leaf mottling and/
or discoloration and reddening. The plant vulnerability to insect damage
increases under drought stress. The aphids also produce honeydew, which
covers the leaf surface. Mold fungi colonize the honeydew producing a black
layer of fungal colonies on corn leaf surface causing the reduction of the photosynthetic leaf activity.
Miscanthus Feeding Insects and Nematodes
of three pairs of leaves. Besides direct damage, yellow sugarcane aphid also
transmits sugarcane mosaic potyvirus (Blackman & Eastop, 2000).
The S. flava was first recorded on M. × giganteus in 2008 in leaf damage
collected from seven locations of Indiana, Illinois, Nebraska, Kentucky, and
Iowa (Bradshaw et al., 2010). Aphids were found on young to old plantings
(1–21 year) in large populations. Aphids feeding leads to leaf death. The
symptoms of M. × giganteus infestations, specifically yellowing and redding
of leaves, were very similar to sugarcane (Nuessly & Hentz, 2002) and sorghum (Costa-Arbulú et al., 2001). The S. flava damage has economic importance as a key factor of M. × giganteus plantation establishment during the
first year of vegetation.
Corn leaf aphid Rhopalosiphum maidis L. (Homoptera: Aphidiidae) is native
to Asia, although they have spread almost worldwide. It occurs sporadically
in cool temperature climate (Blackman & Eastop, 2000). In several countries it
is considered as an economically important pest of Poaceae (Gramineae) monocot crops, namely, wheat, barley, sorghum, and M. sinensis (Carena & Glogoza,
2004; Huggett et al., 1999). This damage potential is especially concerning
because most plant viruses are transmitted by aphids (Hull, 2002) and R. maidis
can transmit the RPV strain (cereal yellow dwarf virus) of barley yellow dwarf
luteovirus (BYDV) to M. × giganteus (Huggett et al., 1999; Jarošová et al., 2013).
8.2.2.4 Identification
The wingless corn leaf aphid is oval, about 2 mm, blue-green in color with
black antennae, legs, and tailpipes. The body and legs are black. The nymphs
are similar to adults with smaller size and underdeveloped antennae and
tailpipes. The winged form of the aphid is about the same size as the wingless ones, with dark green to black body and black tailpipes.
8.2.2.5 Life Cycle
The species reproduce via parthenogenesis. It overwinters in both eggs and
females (in warmer climates) on cereal grasses. The optimum temperature
for development is around 30°C. Corn leaf aphids live in large colonies on
their host plants.
8.2.2.6 Damage
The corn leaf aphids feed by removing plant sap from the phloem. The typical signs of feeding while insect in high population are leaf mottling and/
or discoloration and reddening. The plant vulnerability to insect damage
increases under drought stress. The aphids also produce honeydew, which
covers the leaf surface. Mold fungi colonize the honeydew producing a black
layer of fungal colonies on corn leaf surface causing the reduction of the photosynthetic leaf activity.