VLOGA
PLEVELOV PRI EPIDEMIOLOGIJI VIRUSOV
Gabriella
KAZINCZI, József HORVÁTH and András TAKÁCS
Universitiy
of Veszprém, Georgikon Faculty of Agricultural Sciences, H-8361 Keszthely,
Hungary
Pleveli ne vplivajo na
kakovost in količino pridelkov gojenih rastlin samo neposredno (n. pr. konkurenčen
odnos za hranila in vodo), temveč vplivajo tudi posredno kot alternativni
gostitelji za številne škodljive organizme. Alternativni gostitelji
predstavljajo vir hrane za prenašalce virusov, medtem ko imajo semena in
vegetativni razmnoževalni organi nekaterih plevelnih vrst pomembno vlogo pri
prezimitvi virusov. Namen naše raziskave je bil ugotoviti nove odnose
virus-plevel ter preučiti biotično propadanje plevelov zaradi infekcije z
virusi. V zadnjih letih so bili ugotovljeni nekateri novi odnosi med virusi in
pleveli. Lucernin mozaik, alfamovirus
(AMV), tobakov mozaik, tobamovirus
(TMV) iz Asclepias syriaca; sojin
mozaik, sobemovirus
(SoMV), krompirjev Y potyvirus (PVY)
iz Alisma plantago-aquatica; kumarični
mozaik, cucumovirus (CMV) iz Ambrosia
elatior so bili virusi, ki so jih na Madžarskem izolirali v naravnih
razmerah. Opravljene so bile različne raziskave, s katerimi so preučevali
vpliv infekcije s SoMV ter okoljske dejavnike na kalitev ter vitalnost Chenopodium
vrst. Iz raziskave je mogoče razbrati, da okoljski dejavniki vplivajo na
kalitev semena Chenopodium vrst v večjem
obsegu kot okužba z virusi. Kalitev ter vitalnost semena Chenopodium
vrst je bila zaradi okužbe z virusi zmanjšana za 6-21 % in 1-23 %, odvisno od
vrste. CMV statistično značilno zmanjša odstotek vsebnosti fotosintetskega
pigmenta v listih Datura stramonium,
medtem ko henbane mosaik potyvirus (HeMV)
povzroča motnje pri preskrbi z vodo. TMV infekcija občutno vpliva na zmanjšanje
višine, sveže in suhe mase, mezo in mikroelementov Solanum
nigrum. Nasproten učinek smo opazili v primeru kalija (K), katerega
vsebnost se je občutno povečala v listih, ki so bili okuženi s TMV.
Sklenemo lahko, da virusi neugodno vplivajo na fiziološke procese pri
plevelih, zaradi česar lahko na posreden način pripomorejo k zmanjšanju
njihove konkurenčne sposobnosti.
ABSTRACT
Weeds influence the quality
and quantity of crops not only in a direct way (e.g. by competing for nutrients
and water) but also indirectly as alternative hosts of various pathogens.
Alternative hosts serve as food for the vectors of viruses, while the seeds and
vegetative reproductive organs of certain weed species may play important role
in the epidemiology and overwintering of viruses. The aim of our investigations
was to detect new virus-weed relations and to study biological decline of weeds
due to virus infection. Last years some new host-virus relations were determined.
Alfalfa mosaic alfamovirus (AMV),
tobacco mosaic tobamovirus (TMV) from Asclepias
syriaca; soybeane mosaic sobemovirus (SoMV),
potato Y potyvirus (PVY) from Alisma
plantago-aquatica; cucumber mosaic cucumovirus
(CMV) from Ambrosia elatior were
isolated under natural conditions in Hungary. Different examinations were
carried out to study the effect of SoMV infection and autecological factors on
the germination and seed viability of Chenopodium
species. It could be shown that autecological factors influenced the
germination of Chenopodium seeds to a
greater extent, than did virus infection. Germination and seed viability of Chenopodium
species due to virus infection was reduced by 6-21% and 1-23%, respectively,
depending on species. CMV significantly reduced the photosynthetic pigment
content of Datura stramonium leaves,
while henbane mosaic potyvirus (HeMV)
caused disturbances in water relation. TMV infection considerably decreased the
height, fresh and dry weight, meso- and microelements of Solanum nigrum. Opposite effect was observed in case of potassium
(K) content which were considerably enhanced in the TMV infected leaves. We
conclude that viruses unfavourably influence the physiological processes of the
weeds, therefore -in indirect way- viruses may contribute to the reduction of
their competitive ability.