INTRODUCTION OF VARIETIES OF THE AMERICAN CRANBERRY IN THE LATVIAN SSR

Experiments on testing of varieties of the American large fruited cranberries were begun in 1977 at the research plantation of Jelgava Timber Industry Enterprise.
Seedlings were planted out at spacings of 50 x 50 cm.
Size of a plot for each cultivar was 60 m². During the experiments the following indices were evaluated: growth rhythm, height of vertical shoots, their number per 1 m², number of flowers and berries per 1 m² in 4-fold replications, and percentage of bud rate.
Collection, treatment and investigation of flower buds of the cultivars ‘Stevens’ and ‘Early Black’ were carried out according to the classical method using constant preparates.

Fixation of buds was carried out from April to December 1984–85 at an interval of 3–15 days; the intervals were shorter during the period of expressed budding (May, June) but longer in autumn and winter months.

To fix buds in different stages of development fixatives of Navashine and Karnua were used.
Fixed materials were dehydrated by increasing concentrations of spirit with the interval of 10% (from 10% to 100%) and later on gradually transferred to the paraffin solvent chloroform.
Substitution of chloroform by paraffin was carried out in a thermostat at the temperature 56°–58°C. Microtome cut sections with a thickness of 20–22 were stuck to slides by albumen and stained by iron hematoxiline of Fidengine, partly substaining with eosin, as well as hematoxiline of Erlikh.
After staining, the cut sections were locked in Canadian balm and investigated by microscopes MBI-3 and NU-3/2.

Ten buds per each specimen were observed and correspondence of phenophases expressed in percents.
Biology of flowering was observed directly on trial plots.

Large fruited cranberries were harvested in the 2nd decade of September.
Analyses were carried out in the laboratory according to the following methods: dry matter was determined by drying a string of berries in a thermostat at the temperature 105° until it reached constant weight, sugar by Delle’s method, acidness of cell sap (pH) electrometrically, free acids according to K. Gutmanis, tannins by titreing with solution of potassium permanganate, contents of anthocyanins and catechins were determined photocolometrically; pectins by calcium pectate; benzoic acid by method of Dickens and Pirson; alkali by charring in an electric stove at the temperature 450°– 500°C; specific weight of the sap, by picnometer; dry matter of the sap, refractometrically.

IV International Symposium on Vaccinium Culture

A. Ripa

https://doi.org/10.17660/ActaHortic.1989.241.48