G. Loebenstein, P. H. Berger, A. A. Brunt and R. H. Lawson (eds): Virus and Virus-like Diseases of Potatoes and Production of Seed-Potatoes. Kluwer Academic Publ., Dordrecht (The Netherlands), 2001, 460 pp. László Nowinszky (ed.): The Handbook of Light Trapping. Savaria University Press, Szombathely, 2003.
The aim of our study was to examine the effect of tobacco mosaic tobamovirus (TMV) infection on the growth and nutrient content of S. nigrum leaves. TMV infection significantly reduced the height, the fresh and dry weight of both the shoots and roots. The height of the shoots was reduced by 53% as compared to control. Reduction in fresh and dry weight of shoots and roots due to virus infection varied between 78 and 82%. There was no significant difference in the nitrogen (N), phosphorus (P) and calcium (Ca) content of the healthy and virus infected leaves of S. nigrum. The sodium (Na), magnesium (Mg), iron (Fe), manganese (Mn), zinc (Zn) and copper (Cu) content of the leaves significantly reduced due to virus infection. Opposite effect was observed in case of potassium (K) content, which were considerably enhanced in the TMV infected leaves.
The aim of our study was to investigate the susceptibility of some Chenopodium species (Chenopodium album, C. glaucum, C. berlandieri, C. ugandae) to six viruses (Alfalfa mosaic virus, Cucumber mosaic virus, Obuda pepper virus, Potato virus Y, Sowbane mosaic virus, Zucchini yellow mosaic virus). Fourteen plants of each species were mechanically inoculated and virus susceptibility was evaluated on the basis of symptoms and back inoculation. A series of new host-virus relations were determined.
In this review results are summarized
regarding the effect of virus infection on the physiological processes of
weeds. Through several host-virus model relations the biomass and
seed production, seed viability and germination, nutrient uptake,
drought-resistance and photosynthetic pigment content of healthy and virus
infected plants were compared. Because of their broad host range and high
genetic variability viruses cannot be used for biological weed control. It was
concluded that viruses unfavourably can influence physiological processes of
weeds. Therefore, they may contribute indirectly to the reduction of
competitive ability and population of weeds.
Authors:G. Kazinczi, J. Horváth, A. P. Takács and D. Pribék
In the second part of our study we have examined the effect of Tobacco mosaic tobamovirus (TMV) infection on the germination, seed transmission, seed viability and seed production of S. nigrum. Transmission of TMV by seeds of S. nigrum was 0.3%. Average seed production of the virus infected plants was reduced by 52%, as compared to the healthy control, and TMV infection also delayed generative development. Virus infection did not influence the germination of the seeds. Viability of seeds derived from ripened (blue-black) berries, was significantly reduced by TMV infection.
Authors:A. P. Takács, G. Kazinczi, J. Horváth and R. Gáborjányi
Susceptibility of 33 Lycopersicon
species and intra-specific taxa to 6 viruses such as U/246 strain of Cucumber
mosaic virus (CMV), Pepino mosaic virus (PepMV), Potato virus X (PVX), NTN
strain of Potato virus Y (PVYNTN), Tobacco mosaic virus (TMV) and Tomato mosaic
virus (ToMV) were studied. Inoculated plants were tested for susceptibility on
the basis of symptoms, serological reactions (DAS-ELISA) and back inoculation.
All tested plants were susceptible to PepMV, PVX, TMV and ToMV. However,
Lycopersicon esculentum Mill. convar. parvibaccatum Lehm. var. cerasiforme
(Dun.) Alef.s.l., L. peruvianum (L.) Mill. and L. hirsutum Humb. et Bonpl. were
extreme resistant (immune) to PVYNTN. L. esculentum Mill. convar. infiniens
Lehm. var. flammatum Lehm., L. esculentum Mill. convar. fruticosum Lehm. var.
speciosum Lehm. and L. esculentum Mill. convar. infiniens Lehm. var. validum
Bail. showed extreme resistance to CMV-U/246. The other 30 species and
intra-specific taxa were susceptible to CMV-U/246. New compatible and
incompatible host-virus relations have been reported.
The extreme resistant Lycopersicon intra-specific taxa could be used as
resistance sources in tomato breeding.