Inheritance of thornlessness, hardiness and vigour in blackberries.

Tamas, P.

Crosses between Merton Thornless and various hardy varieties produced plants of very variable vigour. Although some F3 hybrids survived the winter of 1961-1962, artificial freezing tests showed that their hardiness was less than that of Eldorado and Jersey-black. Blackberries were shown to be particularly sensitive to a rapid decrease in temperature. Statistical analysis of the plant material studied showed some correlation between vigour and hardiness in the hybrid populations.