The drought-resistance of 15 nectarine varieties and forms with a sign of male infertility is studied. The research identified genotypes with varying degrees of drought-resistance. The greatest degree of drought-resistance demonstrated the form 33-3-1, 512-86,41-15-2, and grade Kul'dzhinskiy 4x, Krymtsuht, Elbertaziya.

There are allocated some forms of distant hybrids with weak degree of fungal diseases lesion (Taphrina deformans (Berk.) Tul., Sphaerotheca pannosa (Lev.) var. persicae Woron., Clasterosporium carpophilum Aderh., Monilia cinerea Bonord. и Monilia fructigena Fr.) that are of practical interest for breeding such cultivars of peach and nectarine that will resist these pathogens.

The varieties and forms of nectarine resistant to fungi diseases (Clasterosporium carpophilum (Lev.) Aderh., Taphrina deformans Tul., Sphaerotheca pannosa (Wallr.) Fr. Lev. var. persicae Woronich) having the practical interest for modern technology growing and for breeding on these characteristics have been selected.

The results of first varietal study of 7 new genotypes of Prunus cerasifera Ehrh., bred in Nikitsky Botanical Gardens, with male sterility and one similar introduced variety 'Puntsovy' have been given. The value and defects have been marked. Their practical use in selection work and in nurseries has been suggested.

The article deals with agronomic characters of sugar beet MS hybrids developed on the basis of parental components with resistance to Fusarium rots during vegetation period, which were found in studies with the ecological variety test of Be- taintercross. Possibility of combining high productivity and disease resistance in one genotype was confirmed as matter of principle.

There are allocated some forms of distant hybrids with weak degree of fungal diseases lesion (Taphrina deformans (Berk.) Tul., Sphaerotheca pannosa (Lev.) var. persicae Woron., Clasterosporium carpophilum Aderh., Monilia cinerea Bonord. и Monilia fructigena Fr.) that are of practical interest for breeding such cultivars of peach and nectarine that will resist these pathogens.