Warunki termiczno-opadowe a plonowanie ziemniaka w Polsce

Abstract

This study is based upon 10day air temperature and precipitation totals from April to September, registered at 56 meteorological stations of the Institute of Meteorology and Water Management, and the mean potato yield published in the Statistical Yearbook of the Republic of Poland for the years 1961-1995. In June and July a curvilinear statistically significant influence of the thermal-precipitation conditions on the potato yield in Poland was found. It was shown that potato yield was higher than the average if the Sielianinov index in June was 0.8 to 1.8, and in July 0.9 to 2.4. If the Sielianinov index in June was below 0.8 and 0.9 in July, the yield of potato was by 9% lower than the average. If the Sielianinov index in June was above 1.8, and in July above 2.1, the yield decrease reached 7%. The lowest indexes for June and July were found mostly in the western part of Poland, the highest - in the southern part of Malopolska Upland.