Study of reproductive behaviour in low-chill apples in warmer zonesof Argentina

CASTRO, DAMIÁN C.; CERINO, MA. CAROLINA; GARIGLIO, NORBERTO ; RADICE, SILVIA

SCIENTIA HORTICULTURAE

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2016 vol. 199 p. 124 - 132

0304-4238

The domesticated apple (Malus × domestica Borkh.) shows abnormalities in its flowering biology whenit is growing in mild-winter areas. Hence, the flowering phenology and the mating system (e.g., open-,cross- and self-pollination, apomixis and parthenocarpy) of Caricia, Eva, and Princesa apple cultivars werestudied in three consecutive growing seasons. The flowering period ranged between August and Octoberwith wide variation between years, especially in relation to the overlapping of the full-bloom periods.Fruit set by selfing was significant, reaching a mean value of 20% with a minimum of 4.5% and a maximumof 43.7%, depending on the growing season and the cultivar. The self-incompatibility index showed sig-nificant changes between years in Eva and Princesa but not in Caricia. Fruit and seed set were significantlygreater in cross- and open-pollination treatments than by self-pollination, apomixis or parthenocarpy.Those variables were affected by a growing season × treatment interaction. The results indicated thatCaricia, Eva, and Princesa apples show partial to full self-incompatibility, depending strongly on thegrowing season. However, better fruit and seed set rates are obtained by cross-fertilization.