+   Viktor R. Tóth - Research Fellow

Viktor R. Tóth,  MSc, Ph.D.
research fellow
Institute Building A, room 104
tel: +36 87 448244 ext №119
fax: +36 87 448006
personal homapage

Research Area
Research Description
Selected Publications

Travel, work abroad

1994 -

Lajos Kossuth University, Debrecen, MSc in biotechnology.
Thesis title: "Effect of osmotic and ionic stress on carbon assimilation of plants."

2001 -

Lajos Kossuth University, Debrecen, Ph.D. in ecophysiology
Thesis title: "Effect of water and nitrogen stress on growth and photosynthetic activity of maize (Zea mays L.)"

Academic posts
1998 - present

Balaton Limnological Research Institute of Hungarian Academy of Science
1998 - 2001 - assistant research fellow
2001 - present - research fellow

  Research Area

Submerged aquatic macrophytes, photosynthesis, abiotic limitations, distribution, zonation. Reed (Phragmites australis), carbohydrates, aeration, genetics, photosynthesis. GIS.

  Research Description

The photosynthesis and respiration (measured via O2 production at different irradiances and O2 consumption in the dark) of major submerged aquatic macrophytes of lake Balaton [Potamogeton perfoliatus, Myriophyllum spicatum, Ceratophyllum demersum and Najas marina] were measured to determine the key parameters of photosynthesis (IC, IK, PMAX, R). Based on these parameters (and the results of water and sediment chemistry, water optics) we try to develop a model that predicts spatial and temporal distribution of submerged macrophytes in the lake. The predicted results are monitored against actual field distribution of plants using GIS. As a part of this study we work on the estimation of the effects of grazing on the population of submerged macrophytes.

The other important macrophyte in the lake Balaton is the reed (Phragmites australis L.). The decline of reed is the reality here in Hungary, too. We study the changes in the rhyzosphere of the reed stands that might affect the production of reed biomass: organic, P and N content of the sediment, the seasonal and diurnal changes in S2- content and redox potential. We examine the dynamics of growth, the accumulation and redistribution of carbohydrates in the reed, the aeration of the plants. As a part of this year project we started the examination of the ploidity level and the genomic of the reed in Balaton, and want to make a correlation with results of remote sensing.

  Selected Publications

Tóth V., Palmer S.J., Mészáros I., Veres Sz (2002). Spatial distribution of growth vectors and net deposition rates in the ellongation zone of maize plants under conditions of nitrogen deprivation. Biologia Plantarum. 45(2): 241-247.

Tóth V., Mészáros I., Veres Sz., Nagy J. (2002). The effect of available nitrogen on dissipation of excess light via xanthophyll cycle in maize. J. Plant Physiol. 159: 627-634.

  Travels, work abroad

Lancaster University, IEBS, 1995-1996