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In Serbia, sugar beet is grown in the province of Vojvodina mostly. The increase in areas sown to this crop in the province from 30,000 hectares in 1931-1939 to over 70,000 in 1951-2000 provided a large boost to the reproduction of sugar beet pests in this part of the country. More than 15 species are considered major pests of sugar beet. The Department of Plant and Environmental Protection of the Faculty of Agriculture in Novi Sad and the Institute of Field and Vegetable Crops in Novi Sad have been making forecasts of the occurrence of major sugar beet pests since 1961. Over the last 30 years (1975-2004), the following average pest numbers per meter square at the end of the growing season have been recorded: Bothynoderes punctiventris (3.3), Elateridae (3.6), Melolonthidae (1.0), Scotia spp. (0.4), Mamestra spp. (1.5) and Scrobipalpa ocellatella (14.8). In addition to these population dynamics of the following pest species are also monitored: Lixus scabricollis, Chaetocnema tibialis, Cassida spp., Aphis fabae, Pemphigus fuscicornis, Autographa gamma and Loxostege sticticalis.

In the region of Vojvodina, sugar beet weevil (Bothynoderes punctiventris G e r m) is the most important sugar beet pest. Therefore, it would be of great practical benefit if we could establish some regularity in their population dynamics, if it exists and then organize the control of this pest more successfully. During the period of 1961-2004, in Vojvodina, the population density of B. punctiventris was monitored. The annual average of population density varied between 0 and 15 insects per square meter. Analyzing the obtained data it was noticed that there existed a certain periodicity of population outbreaks (maximal densities), approximately of 11 years. Regarding the fact that the solar activity, known as solar flux (observed at 2800 MHz) has a similar periodicity, a statistical processing in the paper of the collected data (periodograms, cross periodograms /real and imaginary ones/, cross densities, cross quadratures, cross amplitudes, squared coherencies as well as cross correlations) was carried out. Inter alia, it was concluded that the population outbreaks of B. punctiventris follows the maximal solar activity (known as solar flux on 2800 MHz), with a lag of seven years.