Zoning of Serbia territory was performed according to the length of active period of photosynthesis for plum cv. Požegača. Relations between thermal indicators of location and plum growing period length are examined. It was found that the length of growing period is of great extent, determined by the length of frost-free period, as well as by the mean annual air temperature and the mean air temperature for the growing period. The study was carried out using data from 55 phenological and 26 climatological stations in Serbia for the period from 1961 to 1995.

Zoning of Serbia territory was performed according to the length of active period of photosynthesis for plum cv. Požegača. Relations between thermal indicators of location and plum growing period length are examined. It was found that the length of growing period is of great extent, determined by the length of frost-free period, as well as by the mean annual air temperature and the mean air temperature for the growing period. The study was carried out using data from 55 phenological and 26 climatological stations in Serbia for the period from 1961 to 1995.

Phenology can contribute to many scientific disciplines from climate change, biodiversity, agriculture and forestry to human health. The knowledge of timing of phenological events and their variability can provide valuable data for planning, organizing and timely execution of certain standard and special (preventive and protective) agricultural activities that require advanced information on the dates of specific stages of crop development. Mathematical models are the basic tools to predict the timing of phenological events.