Pulvinaria
hydrangeae Steinweden (Homoptera, Coccidae)
-
Gabrijel
Seljak
Kmetijsko
veterinarski zavod Nova Gorica, SI-5000 Nova Gorica, Slovenija
Hortenzijev kapar (Pulvinaria hydrangeae Steinweden; Homoptera, Coccidae) je za
Slovenijo nova vrsta kaparja, ki je bila zanesljivo ugotovljena šele v letu
1998 na območju Nove Gorice. Njegova domovina je najverjetneje Vzhodna Azija. V
Evropi je znana od sredine šestedesetih let, trenutno pa je razširjena v
nekaterih državah Južne (Francija, Italija, Slovenija) in Zahodne Evrope
(Belgija, Nizozemska, Švica). Slovenska populacija zanesljivo izvira iz
Italije. Na podlagi nekoliko bolj sistematičnega spremljanja vrste v preteklih
dveh letih ugotavljamo, da je vrsta že precej razširjena v Vipavski dolini in
v Slovenski Istri. Najpogostejši gostitelji so hortenzija (Hydrangea macrophylla), prava lipa (Tilia platyphyllos), lipovec (Tilia
cordata) in javor (Acer spp.).
Vrsta je univoltina. Prezimi 3. nimfalni stadij, zrele samice se pojavljajo od
konca aprila do začetka junija, ko oblikuje podolgovato in zelo opazno jajčno
vrečko. Višek izleganja ličink je v drugi polovici junija.
Hortenzijev kapar je brez
dvoma škodljiv za hortenzije. Pri močnem napadu grmi postopno oslabijo, nakar
lahko posamezni poganjki ali celi grmi tudi odmrejo. Za druge gostiteljske
rastline je ta opredelitev manj zanesljiva. Naravnih sovražnikov, ki bi
omejevali populacijo je za zdaj še malo. Med značilne predatorje lahko štejemo
vrsto Coccophagus lycimnia (Walk.) (Hymenoptera,
Aphelinidae), vendar jo na opazovanem območju nismo našli med predatorji te
vrste. Našli smo nekatere splošne predatorje
kaparjev, kot je Exochomus quadripustulatus L. in vrste iz rodu Scymnus (Coleoptera, Coccinellidae). Najprimernejši čas za
zatiranje z insekticidi je proti koncu junija, ko se izleže večina ličink ali
pozno jeseni z oljnimi pripravki.
V prispevku bo primerjalno
obdelana morfologija in taksonomija vrste Pulvinaria
hydrangeae skupaj z drugimi vrstami iz rodu Pulvinaria,
ki so doslej ugotovljene na ozemlju Slovenije.
Pulvinaria hydrangeae Steinweden
(Homoptera,
Coccidae) - a new harmful scale species
in Slovenia
The
cottony hydrangea scale (Pulvinaria
hydrangeae Steinweden; Homoptera, Coccidae), with certainty identified in
the area of Nova Gorica only in 1998, is a new scale species in Slovenia. Its
origin is in all probability East Asia. In Europe it is known since the mid
sixties and at the present it is diffused in some countries of Southern Europe
(France, Italy, Slovenia) and West Europe (Belgium, the Netherlands, Switzerland).
The Slovene population originates without any doubt from Italy. Based on a
systematical monitoring of the species in the last two years it can be stated
that the species is already quite diffused in the Valley of Vipava as well as in
the Slovene Istria. The most frequent hosts are the Hydrangea
macrophylla, Tilia platyphyllos, Tilia
cordata and the Acer spp. The
species is univoltine and it overwinters in the 3rd nymphal stadium,
the mature female appears at the end of April up to the beginning of June,
forming in this period an oblong and very visible ovisac. The culmination of the
larva hatching is in the second half of June.
The
cottony hydrangea scale is without doubt harmful for the hydrangea. The severely
attacked bushes weaken gradually. Single shoots or even whole bushes can then
die away. For other host plants the damages caused by this species are less
important. At present there are very few natural enemies which would restrain
the population. A common predator is the species Coccophagus lycimnia (Walk.) (Hymenoptera, Aphelinidae), which
however, couldn't be found as predator of the said species in the monitored area.
But also some other predators of the scale like the Exochomus quadripustulatus L. and some species of the genus Scymnus
(Coleoptera, Coccinellidae) were found. The most appropriate time for the
control with insecticides is at the end of June when the majority of larvae
hatch or with oil insecticides in late autumn.
In
the present paper the morphology and the taxonomy of the species Pulvinaria
hydrangeae will be described in
comparison with other species of the genus Pulvinaria
known up to the present in the territory of Slovenia.