Reproductive Characteristics of the Progeny of Blackthorn (P. spinosa) x Topalka* Plum (P. domestica) Combination
Institute of Highland Animal Husbandry and Agriculture, BG-5600 Troyan, Bulgaria
MINEV, I., 2000. Reproductive characteristics of the progeny of blackthorn (P. spinosa) x Topalka plum (P. domestica) combination. Bulg. J. Agric. Sci., 6: 661-664
Twenty plants, progeny of blackthorn (P. spinosa) and Topalka plum (P. domestica) combination, were studied. Pomological characteristics of fruits was made. Fertility and terms of ripening were studied.
The average fruit weight of progeny plants is within 2.5 g and 13.8 g, being 5-9 g in almost half of them. In terms of heritability of average fruit weight, hybrids are intermediate to the parent couple, the values differentiating considerably from the two parents. The average stone weight is 0.2-0.9 g, being 0.2-0.5 g in 2/3 of them. This index of the hybrids is intermediate to the parent couple, a considerable number of them having an average stone weight close to and reaching that of the maternal form.
The progeny fruits have a spherical shape and dark-blue fruit skin color. The stone does not detach from the fruit flesh, which is similar to the parent forms.
Total sugar content of fruits is 7.7-12.45%, acids – 1.87-3.35% and tannin content is 0.438-0.936%. Blackthorn is dominating in heritability of acid and tannin content.
Key words: plums, hybrids, fruits, average stone weight, fertility, picking ripeness, chemical composition