FACTORS AFFECTING FROST TOLERANCE OF RASPBERRY CANES

In 1970–1973 the cold hardiness of two raspberry cultivars – Latham /frost hardy/ and Malling Promise /frost sensitive/ treated with different rates of mineral fertilization has been studied.

The cold hardiness of raspberry canes was highly correlated with the diurnal fluctuations of air temperature.

During the first stage of cold hardiness development no difference in the level of attained frost tolerance was found between the 2 cultivars.
The highest level of hardiness was reached in both cultivars in January – -33.0°C Latham, -37.2°C Malling Promise.
However, from the end of January until the beginning of spring there was a marked difference in the rate of dehardening of the two cultivars.
Latham maintained longer the acquired maximal level of hardiness and its loss was gradual, whereas the loss of hardiness proceeded at a much faster rate in Malling Promise.

The content of water soluble proteins, water and the mineral nutrients /N, P₂O₅, K₂O, CaO, MgO/ did not exert significant influence on the development of frost hardiness of raspberry canes.
There was no effect of applied fertilizers and especially their high doses on the development of cold hardiness.

Symposium on Winterhardiness in Woody Perennials

E. Pacholak

https://doi.org/10.17660/ActaHortic.1978.81.11