摘要
A study was conducted to describe the progression of bud dormancy in 1-year-old apple （Malus x domestica Borkh） shoots grown at two contrasting climatic conditions （Belgium, temperate and Ethiopia, tropics）. The experiment was carried out on ＂Golden＂ and ＂Gala＂ cultivars for two consecutive years （2010/2011 and 2011/2012）. Moreover, a validation experiment was conducted on ＂MM106＂ apple rootstock during 2010/2011 only in Ethiopia. Variations in inverse of time to 50% budburst were interpreted in terms of evolution of growth capacity of the buds. Despite differences observed with chilling accumulation later in winter or early in spring, depending on environments, depth of endodormancy intensity during winter can be summarized as follows： buds from pruned shoots were less endodormant than terminal buds of the intact shoots and terminal buds were more endodormant than the dormancy intensity of upper buds of the disbudded shoots, suggesting proximal buds can grow more readily than does terminal ones. Our results provide evidence for the existence of a considerably strong paradormancy inhibition by distal shoot parts and buds, which was more pronounced in Ethiopia than in Belgium, highlighting the importance of designing and applying appropriate pruning and dormancy avoidance strategies in mild-winter climates. Finally, as still there is knowledge gap on bud dormancy progression and its control mechanism especially under mild climates, our study highlights the need for further in-depth research using biological and biochemical tests.
