| Abstract [eng] |
Wolyniec Jan Saulius Summary Investigation of immunodeficient tw (tweaky spike) and be (branched ear) barley mutants resistance to fungal pathogens Plants have evolved a number of mechanisms to defend themselves against environmental stresses such as pathogen invasion. The investigacion of imunodeficient barley tw and be mutants to resistance against fungi pathogens were made at Vilnius University, Botanical Garden, in 2005. There were used salicylic acid (SA), in international IUPAC nomenclature: 2-hydroksibenzoic acid. Salicylic acid (SA) serves as a signaling molecule for activation of several plant defence responses including systemic aquired resistance (SAR). Fungi pathogens studied in investigation were: micromicetes, ergot (Claviceps purpurea), smut (Ustilago nuda), powdery mildew (Blumeria graminis f. sp. Hordei), leaf rust (Puccinia striiformis) and net blotch (Dreschlera teres) The action of SA was tested in field conditions on six barley allelic mutants tw (tweaky spike) and two mutants be (branched ear) induced in two different cultivars `Auksiniai II` and `Auksiniai 3`. These were also tested in investigation. The frequency of fungal diseases was determined in natural conditions of investigation - in field. The meteorogical and other environmental conditions had strong influence on pathogen infection in field conditions. Fungal deseases was determined of different conditions of SA treatment. Grains were soaked in SA solutions of 0,00 (control group); 0,05; 0,25; 0,50 and 1,00 mM concentrations for 12h, and then were planted in the experimental field of Botanical Garden. Part of the plants were not sprayed with SA, while the other plants were sprayed once, twice or three times with the same 0,05 mM SA. The ph 6,5 of SA solutions was regulated with KOH. Salicylic acid enlarged resistance to fungi pathogens in all investigated barley cultivars. Imunodeficient tw and be barley mutants was manifested by increased susceptibility to Ustilago nuda and Claviceps purpurea, as well as by an increased frequency of moldy germinating grains. The same fact was obserwed with Dreschlera teres and Blumeria graminis. Auksiniai II were much more resistant to these fungal pathogens than tw mutants. Puccinia striiformis fungal pathogens in any group of investigated barley plants were not found. Auksiniai II and tw mutants increased resistance to fungi pathogens with treatment of salicylic acid. Salicylic acid has a big influence in barley resistance. It have a positive effect on resistance induction to all aforementioned fungal pathogens. |
