Estimating the yield of potato non-mulched using climatic elements.

ABSTRACT We aimed to evaluate the effects of climatic elements on potato yield and create a model with climatic elements for estimating the potato yield, using the results of the regional adjustment tests of potato. We used 86 data of the yield data of a potato variety, Sumi, from 17 regions over 11 years. According to the results, the climatic elements showed significant level of correlation coefficient with marke-table yield appeared to be almost every climatic elements except wind velocity, which was daily average air temperature (Tave), daily minimum air temperature (Tmin), daily maximum air temperature(Tmax), daily range of air temperature (Tm-m), precipitation (Prec.), relative humidity (R.H.), sunshine hours (S.H.) and days of rain over 0.1 mm (D.R.) depending on the periods of days after planting or before harvest. The correlations between these climatic elements and marketable yield of potato were stepwised using SAS, statistical program, and we selected a model to predict the yield of marketable potato, which was y = 7.820×Tmax_1 - 6.315×Prec_4 + 128.214×DR_8 + 91.762×DR_3 + 643.965. The correlation coefficient between the yield derived from the model and the real yield of marketable yield was 0.588 (DF 85).Keywords : potato, marketable yield, sumi, non-mulched, climatic elements, correlation coefficient, stepwise, modeling