PL
Celem prezentowanej pracy była ocena odporności na Bipolaris sorokiniana (Sacc.) Shoem. potomstwa regenerantów uzyskanych z tkanki kalusowej kostrzewy łąkowej, selekcjonowanej in vitro na metabolitach tego patogena. Cztery genotypy zregenerowane z kalusów odmiany Skrzeszowicka uprawiano przez trzy lata w warunkach polowych. Każdego roku pobierano z nich liście z objawami chorobowymi. Następnie liście badano mikroskopowo pod kątem zasiedlenia ich przez zarodniki badanego grzyba. Z powyższych genotypów uzyskano potomstwo wsobne i dialleliczne. W warunkach szklarniowych poddano je sztucznej inokulacji mieszaniną grzybni i zarodników B. sorokiniana. Rośliny zregenerowane w kulturach tkankowych przez kolejne dwa lata nie wykazywały objawów porażenia tym patogenem. Dopiero w trzecim roku uprawy zanotowano występowanie konidiów B. sorokiniana na około 4% badanych liści. Wskaźniki chorobowe potomstwa wsobnego i diallelicznego, obliczane po przeprowadzonej infekcji szklarniowej, wykazały mniejszą podatność tych roślin na zakażanie w stosunku do roślin kontrolnych.
EN
Meadow fescue is a very valuable grass which may be cultivated on different soils, on grassland and in recreation places. The fescue is often infected by fungi, specially of Bipolaris and Drechslera genera. The appearance of these pathogens decreases the yield of green mass and fodder quality. The purpose of this work was to evaluate the field resistance of meadow fescue forms obtained in vitro from calli selected on metabolites of B. sorokiniana, to this pathogen. Moreover, the resistance of regenerant progenies to B. sorokiniana was estimated too. Four genotypes regenerated from callus of Skrzeszowicka cultivar were cultivated in field conditions for three years. The microscopy identification of pathogens infected leaves of these forms was done every year. The regenerants were self-pollinated and diallelic crossed. The progenies S₁ and F₁ were cultivated in pots in greenhouse conditions and artificially inoculated with spores and mycelium of B. sorokiniana. The leaf infection degree was recorded in 0-5 score and then the coefficients of Average Severity Index were calculated. In case of S₁ progeny the plants without disease symptoms were cultivated in the field and their resistance to B. sorokiniana were estimated by pathogen microscopy identification. On regenerant leaves the occurrence of B. sorokiniana spores was not observed for two years of field breeding. In the third year the appearance of this fungus spores was noted on 4% studied leaves. The S₁ and F₁ progeny showed less infection degree after artificial inoculation in comparison to control plants. Only 3% leaves of S₁ progeny cultivated in field conditions were infected by B. sorokiniana spores. Obtained results indicate the purposefulness of breeding works using the plants regenerated in vitro on fungus metabolites although these forms do not show the full resistance to studied pathogen.