Foundations and methods of modeling of projected growth potato globoderosis on agrometeorological conditions

Abstract

The purpose of the research: to develop verbal, analogous, mathematical models of projected growth of potato globoderosis depending on agrometeorological conditions. Materials and methods. Analysis of national and foreign literature regarding epiphytotiology, modeling was performed, as well as available literature data and personal supervision about influence of meteorological conditions on the potato globoderosis development were generalized. A database received in Kondrovo of Kaluga Region was used in order to develop verbal, analogous, mathematical model. One experimental field was chosen out of 40 experimental fields and plots of land where Sineglazka vulnerable variety was grown during 1979-1993. On the field with average soil quality the population density of nematodes varied from 14,900 to 27,300 (average 20,600) ovicells and larvas at the 100 cubic cm of soil. Globoderosis development was evaluated according to the scale for at-ground visual appraisal of defeat potato plants by globoderosis in points annually in July. Phenological, phytosanitary and phytohelminthological metering and supervision at the experimental field were conducted during vegetational season. Correlation and regression analysis of collected material was conducted using software application Microsoft Excel. Results and discussion. Сorrelation coefficient for meteorological factors closely related to globoderosis development over 15 years were calculated with the help of correlation analysis. Predictors (average daily temperature, quantity and amount of rainfall) for short period forecast of globoderosis development while planting of potatoes with average level of fertility were determined. As the result of regression analysis mathematic models of projected growth globoderosis depending on agrometeorological factors were received. Confidence of a mathematical model, i.e. differences of expectancy record from retrospective average 3.6%. Correspondence of mathematic model was checked by historical data using correlation coefficient between the result of projected growth globoderosis and measurement data. It is 0.83. Accuracy of forecast varied from -36.8 to 36.5%.