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Miscanthus Feeding Insects and Nematodes
8.4.1 PPNs − Potential Vector of Plant Viruses
The nematode survey associated with M. × giganteus was provided in
established crop’s stands of 1–10 years of age representing, consequently, eight
locations and six soil types in Ukraine (out of which three were contaminated
by trace elements) and nine localities covering eight soil types in Poland
(Figure 8.3).
The obtained results indicated that group of plant-feeding species was represented by 53 species belonging to 22 genera and 10 families (Stefanovska
et al., 2020). Comparison of population density of plant-feeding nematodes
recorded in both Ukraine and Poland with the damage threshold values
established by Mekete et al. (2011b) demonstrated that the populations of
several PPNs, which are known as vector of plant viruses, were above the
estimated damage threshold.
Two dangerous plant viruses, specifically Norovirus (NEPO) and
Tobravirus (TOBRA), have nematode vectors. The only known nematode vectors of NEPO are in the genera Xiphinema and Longidorus whereas TOBRA is
transmitted by Trichodorus and Paratrichodorus (Macfarlane, 2003; MacFarlane
& Neilson, 2009).
A total of ten nematode species capable of vectoring plant viruses
were recorded in Ukraine and Poland in surveyed M. × giganteus plantations. Two species of the genus Longidorus: L. elongatus and L. attenuatus
were observed only in Poland with a population range of 284–300 individuals per 100 cm 3 . They exceeded the damage level (5–25 individuals
per 100 cm 3 ) by 2.5-fold. Species of the genus Xiphinema were associated
with M. × giganteus plantations in both countries with population densities below the estimating threshold. Nematodes of genera Xiphinema
would not likely impact negatively the crop development and biomass
yield in the observed plantations. These results are not inconsistent with
Mekete et al. (2011b) who showed that this genus was potentially damaging for M. × giganteus. Emery et al. (2017) observed that Miscanthus is
suitable to Xiphinema.
Three species of genus Trichodorus in Poland T. sparsus, T. similis, and T.
viruliferus vs. one species in Ukraine T. sparsus were recorded. PPNs of genus
Paratrichodorus recovered from the root zone of M. × giganteus were represented by two species: P. pachydermus and P. teres in both countries.
8.4.2 Ecto-, Endoparasites, and Hyphal/Root Feeders
Nematode species representing ectoparasites belonging to the genera
Mesocriconema, Criconema, Paratylenchus, Geocenamus, Bitylenchus, Merlinius,
Neodolichorhynchus, Sauertylenchus, Scutylenchus, and Amplimerlinius were
recovered at the maximum population densities of 60–70/100 cm 3 of soil.
These values are considerably lower than in suggested damage threshold
value that is estimated as 300–600 nematodes per 100 cm 3 .
Miscanthus Feeding Insects and Nematodes
8.4.1 PPNs − Potential Vector of Plant Viruses
The nematode survey associated with M. × giganteus was provided in
established crop’s stands of 1–10 years of age representing, consequently, eight
locations and six soil types in Ukraine (out of which three were contaminated
by trace elements) and nine localities covering eight soil types in Poland
(Figure 8.3).
The obtained results indicated that group of plant-feeding species was represented by 53 species belonging to 22 genera and 10 families (Stefanovska
et al., 2020). Comparison of population density of plant-feeding nematodes
recorded in both Ukraine and Poland with the damage threshold values
established by Mekete et al. (2011b) demonstrated that the populations of
several PPNs, which are known as vector of plant viruses, were above the
estimated damage threshold.
Two dangerous plant viruses, specifically Norovirus (NEPO) and
Tobravirus (TOBRA), have nematode vectors. The only known nematode vectors of NEPO are in the genera Xiphinema and Longidorus whereas TOBRA is
transmitted by Trichodorus and Paratrichodorus (Macfarlane, 2003; MacFarlane
& Neilson, 2009).
A total of ten nematode species capable of vectoring plant viruses
were recorded in Ukraine and Poland in surveyed M. × giganteus plantations. Two species of the genus Longidorus: L. elongatus and L. attenuatus
were observed only in Poland with a population range of 284–300 individuals per 100 cm 3 . They exceeded the damage level (5–25 individuals
per 100 cm 3 ) by 2.5-fold. Species of the genus Xiphinema were associated
with M. × giganteus plantations in both countries with population densities below the estimating threshold. Nematodes of genera Xiphinema
would not likely impact negatively the crop development and biomass
yield in the observed plantations. These results are not inconsistent with
Mekete et al. (2011b) who showed that this genus was potentially damaging for M. × giganteus. Emery et al. (2017) observed that Miscanthus is
suitable to Xiphinema.
Three species of genus Trichodorus in Poland T. sparsus, T. similis, and T.
viruliferus vs. one species in Ukraine T. sparsus were recorded. PPNs of genus
Paratrichodorus recovered from the root zone of M. × giganteus were represented by two species: P. pachydermus and P. teres in both countries.
8.4.2 Ecto-, Endoparasites, and Hyphal/Root Feeders
Nematode species representing ectoparasites belonging to the genera
Mesocriconema, Criconema, Paratylenchus, Geocenamus, Bitylenchus, Merlinius,
Neodolichorhynchus, Sauertylenchus, Scutylenchus, and Amplimerlinius were
recovered at the maximum population densities of 60–70/100 cm 3 of soil.
These values are considerably lower than in suggested damage threshold
value that is estimated as 300–600 nematodes per 100 cm 3 .