Relation between air temperature and length of vegetation period of potato crops

On the basis of multiannual field experiments conducted in central Poland the relation between the air temperature sum (TSUM) and the length of vegetation period (Lv) of potato crops is described. It is shown that air temperature has significant influence on the duration of vegetation. The exponential equations describing relationship between Lv and TSUM are formulated for three maturity groups of potato crops: early, medium and late. The data sets of Lv and TSUM with their descriptive statistics for these potato groups are given as well.