INCREASED ROOTING AND SURVIVAL OF COTINUS-COGGYGRIA CUTTINGS FROM ETIOLATED STOCK PLANTS

Rooting and survival trials on cuttings of Cotinus coggygria cv. Royal Purple were carried out in two successive years following stock plant ctiolation. Two clones were used which differed in age and source, clone SB stock plants were six years old, clone LP one year old. Etiolated SB shoots taken in May/June of each year showed a higher rooting percentage than those of control plants. The rooting percentage of control LP stock plants was higher than SB, and etiolation did not enhance this. Cuttings from both clones were difficult to root later in the season. The growth rate of etiolated SB cuttings, as indicated by lateral extension and leaf number was significantly greater than control cuttings in both seasons. In contrast there was no significant difference in the growth rate of LP cuttings taken in June. The survival of etiolated SB cuttings taken in May of the first season was significantly higher than that of control cuttings. A similar enhanced survival was recorded in the following year with etiolated cuttings from both clones. However, no cuttings were lost over the winter period. The results are discussed in relation to enhanced survival following etiolation.