Physiological time of Japanese Plum (Prunus cerasifera EHRH) cv. Methley, calculated in high altitudes with temperate climate

Abstract

Aim: determine the physiological time (GDD and CU) of the phenological phases of the Japanese plum cv. Methley, cultivated in high altitudes with temperate climate.
Design/methodology/approach: through daily observation, record of the appearance of phenological phases and use of Snyder´s method (1985), in twenty plum trees cv. Methley grafted on Mirobolano plum, the GDD of each phenological phase were quantified; CU were determined through three models (Richardson et al., 1974, Vega et al., 1990 and Shaltout and Unrath, 1983).

Results: the physiological time of the cultivar had small quantitative variations for the same phenological phases in the studied years (2015 and 2016). The models for the CU calculation quantified different amounts of chilling temperatures.

Study limitations/implications: the use of models for CU quantification, typical for temperate latitudes, in intertropical regions, makes difficult to monitor the accumulation of necessary cold to resume the growth of deciduous fruit trees.

Findings/conclusions: it is recommended not to use own models from temperate latitudes, in high altitudes with temperate climate intertropical zones; in this case, it is right the use Vega´s model et al (1990).