The early growth and tillering capacity of two barley (Hordeum vulgare L.) varieties (Dicktoo and Kompolti Korai) were investigated in a gradient growth chamber. The identification of these crop traits is important under organic agricultural conditions in the selection of new varieties for competitiveness against weeds. The results clearly demonstrate that the initial development of the two barley varieties depended considerably on the plant growth conditions. The temperature gradient was found to have the greater effect during early development, causing significant differences in all the traits at all measurement dates. The results indicate that the two varieties differ substantially for two characteristics important for organic farming. As regards tillering ability, Dicktoo appears to be the more desirable type, despite the fact that it is unable to achieve its tillering potential at higher temperatures. Under certain ecological conditions, the relative temperature insensitivity of Kompolti Korai could be an advantage. As far as early development vigour is concerned, Kompolti Korai is clearly a desirable type for organic farming, since it produced rapidly growing, robust plants in all the temperature ranges. From the point of view of organic breeding, a combination of the valuable traits of these two varieties could be the way forward.
Tischner, T., Veisz, O. (1996): Cross-gradient growth bench for the optimization of plant growth conditions. Biotronics, 25, 89-97.
'Cross-gradient growth bench for the optimization of plant growth conditions. ' () 25 Biotronics : 89 -97 .
Tischner, T., Köszegi, B., Veisz, O. (1997): Climatic programmes used in the Martonvásár phytotron most frequently in recent years. Acta Agron. Hung., 45, 85-104.
'Climatic programmes used in the Martonvásár phytotron most frequently in recent years. ' () 45 Acta Agron. Hung. : 85 -104 .
Lemerle, D., Verbeek, B., Cousens, R. D., Coombes, N. E. (1996): The potential for selecting wheat varieties strongly competitive against weeds. Weed Research, 36, 505-513.
'The potential for selecting wheat varieties strongly competitive against weeds. ' () 36 Weed Research : 505 -513 .
Seavers, G. P., Wright, K. J. (1999): Crop canopy development and structure influence weed suppression. Weed Research Oxford, 39, 319-328.
'Crop canopy development and structure influence weed suppression. ' () 39 Weed Research Oxford : 319 -328 .
Köszegi, B., Kovács, G. (2003): Gradient chamber studies on the dry matter accumulation of winter emmer [Triticum turgidum ssp. dicoccon (Schrank) Thell.] landraces in the seedling stage. Acta Agron. Hung., 51, 413-418.
'Gradient chamber studies on the dry matter accumulation of winter emmer [Triticum turgidum ssp. dicoccon (Schrank) Thell.] landraces in the seedling stage. ' () 51 Acta Agron. Hung. : 413 -418 .
Köszegi, B., Kovács, G. (2004): Trends in the heading dates of winter emmer [Triticum turgidum ssp. dicoccon (Schrank)] landraces of different origin in the gradient growth chamber. Acta Agron. Hung., 52, 319-322.
'Trends in the heading dates of winter emmer [Triticum turgidum ssp. dicoccon (Schrank)] landraces of different origin in the gradient growth chamber. ' () 52 Acta Agron. Hung. : 319 -322 .
Didon, U. M. E., Hansson, M. K. (2002): Competition between six spring barley (Hordeum vulgare ssp. vulgare L.) cultivars and two weed flora in relation to interception of photosynthetic active radiation. Biol. Agric. Hort., 20, 257-273.
'Competition between six spring barley (Hordeum vulgare ssp. vulgare L.) cultivars and two weed flora in relation to interception of photosynthetic active radiation. ' () 20 Biol. Agric. Hort. : 257 -273 .
Eisele, J. A., Köpke, U. (1997): Choice of cultivars in organic farming: new criteria for winter wheat genotypes. 2. Weed competitiveness of morphologically different cultivars. Pflanzenbauwissenschaften, 1, 84-89.
'Choice of cultivars in organic farming: new criteria for winter wheat genotypes. 2. Weed competitiveness of morphologically different cultivars. ' () 1 Pflanzenbauwissenschaften : 84 -89 .
Hoad, S., Neuhoff, D., Davies, K. (2005): Field evaluation and selection of winter wheat for competitiveness against weeds. pp. 61-66. In: Lammerts van Bueren, E. T., Goldringer, I., Ostergard, H. (eds.), Proceedings of the COST SUSVAR/ECO-PB Workshop on Organic Plant Breeding Strategies and the Use of Molecular Markers. Driebergen, 17-19 January, 2005.
Proceedings of the COST SUSVAR/ECO-PB Workshop on Organic Plant Breeding Strategies and the Use of Molecular Markers. Driebergen, 17-19 January , () 61 -32 .