Acta Univ Latv (2005) 691: 31–40

Effect of environmental factors on the propagation of deciduous azalea by cuttings. I. Influence of stock plant management on rooting and carbohydrate status

Abstract

The aim of this study was to estimate the effect of stock-plant forcing in a greenhouse during spring as a management technique for stock plants on rooting and on changes of carbohydrate contents of cuttings from deciduous azalea cultivar ‘Polārzvaigzne’ during the rooting period. Forcing of the stock plants enabled to start propagation of deciduous azalea by cuttings one month earlier. Conditions in the greenhouse promoted accumulation of carbohydrates in the shoots of forced stock plants compared to control plants. However, the stock-plant forcing affected neither the number of rooted cuttings nor the duration of time necessary for maximum rooting. The patterns of carbohydrate changes were similar in forced and control cuttings. The amount of reducing sugars, total soluble sugars, and starch increased significantly in the cuttings after severing, while the level of sucrose generally fluctuated over time. After root emergence the content of reducing sugars, sucrose, and starch decreased initially in the stem base and later in the leaves of cuttings. The content of starch was better related to the rooting process than the content of total soluble sugars.