MORPHOLOGICAL CHARACTERISTICS OF THE NECTARY AND COMPOSITION OF NECTAR IN FLOWERS OF SELECTED APPLE CULTIVARS

Stomata of the floral, automorphic nectary in apple cultivars are functional during the first stage of blossoming.
Their opening and closing is more or less rhythmic, as it is proven by the appearance of rhythmic secretion of nectar.
It is very likely that the position of nectary stomata indicates the ecological type of the cultivars.
The majority of the studied cultivars belongs to the mesomorphic type.
The sunken stomata and the wrinkles of the cuticle retain nectar, which may facilitate the multiplication of certain bacteria, as e.g. Erwinia amylovora. The main sugar components of the nectar in apple are glucose, fructose and sucrose.
On the basis of the quantity and proportion of these sugar components, the nectar of most apple cultivars belongs to the sucrose-rich and sucrose-dominant type.
The nectar in fireblight resistant apple cultivars is diluted and the sucrose content is low.

Eucarpia symposium on Fruit Breeding and Genetics

E. Nagy Tóth, T. Bubán, M. Hevesi, Z. Orosz-Kovács, L.G. Szabó

apple, nectary, nectar, Erwinia amylovora

https://doi.org/10.17660/ActaHortic.2000.538.52