Creation of infection phone of F. sporotrichiella var. sporotrichioіes (sherb.) віlaі for estimation and selection sunflower breeding material resistant to fusariose

During last ten years an affection of sunflower by fusariose is detected more often almost in all regions of its cultivation. Breeding for resistance is urgent. The results of trials of various inoculum doses of F. sporotrichiella var. sporotrichioides applied in boxes with soil for creation cruel enough infection phone in test of two lines, three hybrids, and two sunflower O.P. varieties arc considered. Four groups of 15-days plants different by their lesion extent of main root and growth depression are described. It is shown that for lines, hybrids, and O. P. varieties are necessary different inoculum doses in creation cruel enough infection phone.