'Laskava' - a new peach cultivar resistant to powdery mildew disease (Sphaerotheca pannosa (Wallr.:Fr.) Lev.).

摘要

The new Bulgarian peach breeding programme started at the Fruit-Growing Institute in Plovdiv in 1989. One of the major aims was the establishment of cultivars resistant to powdery mildew disease (Sphaerotheca pannosa (Wallr.:Fr.) Lev.) in peach and bearing fruits of a very good sensory profile. The new cultivar 'Laskava' resulted from the breeding programme and was formally released in Bulgaria in February 2009. 'Laskava' was developed by interspecific hybridization of the species Prunus persica (L.) Batsch and Prunus ferganensis (Kost. & Rjab.) Kov. & Kost. It was selected from the fourth-generation hybrid population (F₄) obtained by double open pollination of selected hybrids of the parent combination 'J. H. Hale' x ('Elberta' x 'Ferganskiy zholtiy'). Fruits of 'Laskava' ripen at the beginning of August, a week after those of 'Redhaven'. They are very large, 73.6x75.8x77.2 mm in size, their mean weight being 230 g. The shape is almost spherical with a well outlined tip. The suture is well defined, the pedicel cavity is narrow and deep. Fruit skin is moderately fuzzy and 70-80% of the surface is covered with a bright carmine blush. Fruit flesh is intensive yellow in colour with a slight redness close to the stone. It has a gentle texture; it is very juicy with a balanced sweet-sour taste and a good aroma. The mean weight of the stone is 8.92 g representing 3.88% share of the total fruit. It detaches easily from the fruit flesh. The tree is of a moderate to vigorous growth. The flowers are bell-shaped and the leaf glands are kidney-shaped. 'Laskava' shows obvious resistance under field conditions to the causative agent of the major disease in peaches (Sphaerotheca pannosa (Wallr.:Fr.) Lev.).