ABSTRACT
Prevention of fungal diseases caused by Fusarium species, including F. culmorum, and thus the accumulation of mycotoxins in wheat ears, is a constant challenge focused on the development of new, effective crop management solutions. One of the currently most ecologically attractive approaches is biological control using natural antagonistic microorganisms. With this in mind, the antagonistic potential of thirty-three Clonostachys and Trichoderma strains was assessed in this work. Screening tests were carried out in in vitro cultures, and the observed potential of selected Trichoderma and Clonostachys strains was verified in field and semi-field experiments with two forms of wheat: winter cv. Legenda and spring cv. Bombona. Three strains, namely C. rosea AN291, T. atroviride AN240 and T. viride AN430 were reported to be most effective in inhibiting the growth of F. culmorum KF846 and the synthesis of DON, 3AcDON and ZEN under both laboratory and semi-controlled field conditions. Observations of the contact zones of the tested fungi in dual cultures exposed their mycoparasitic abilities against KF846. In addition, studies on liquid cultures have demonstrated the ability of these strains to eliminate F. culmorum toxins. Meanwhile, the strains of T. atroviride AN35 and T. cremeum AN392 used as soil inoculants in the field experiment showed a different effect on the content of toxins in ears (grains and chaffs), while improved wheat yield parameters, mainly grain health in both wheat cultivars. It is concluded that the selected Trichoderma and Clonostachys strains have a high potential to reduce the adverse effects of F. culmorum ear infection; therefore, they can be further considered in the context of potential biocontrol factors and as wheat crop improvers.
ABSTRACT
Fusarium head blight (FHB), caused by the fungal plant pathogen Fusarium, is a fungal disease that occurs in wheat and can cause significant yield and grain quality losses. The present paper examines variation in the resistance of spring wheat lines derived from a cross between Zebra and Saar cultivars. Experiments covering 198 lines and parental cultivars were conducted in three years, in which inoculation with Fusarium culmorum was applied. Resistance levels were estimated by scoring disease symptoms on kernels. In spite of a similar reaction of parents to F. culmorum infection, significant differentiation between lines was found in all the analyzed traits. Seven molecular markers selected as linked to FHB resistance QTLs gave polymorphic products for Zebra and Saar: Xgwm566, Xgwm46, Xgwm389, Xgwm533, Xgwm156, Xwmc238, and Xgwm341. Markers Xgwm389 and Xgwm533 were associated with the rate of Fusarium-damaged kernels (FDK) as well as with kernel weight per spike and thousand kernel weight in control plants. Zebra allele of marker Xwmc238 increased kernel weight per spike and thousand kernel weight both in control and infected plants, whereas Zebra allele of marker Xgwm566 reduced the percentage of FDK and simultaneously reduced the thousand kernel weight in control and infected plants.
