The objective of the study was to determine feeding preferences of the khapra beetle (Trogoderma granarium Everts) towards some plant products. The material for the investigations was composed of grain of four barley varieties: Brenda, Krona, Maresi, Rasbet; barley malt, and nutlets of three varieties of buckwheat: Hruszowska, Emka and Kora. The reference material comprised wheat grain of the commercial variety Almari. The results showed that the development of T granarium larvae on barley grain and malt took longer than on wheat grain. The authors observed that buckwheat nutlets were comparable to barley kernels as a food for the development of the pest. The pest showed more feeding preferences to buckwheat products, grits and meal to barley grain.

The aim of the experiment was to assess the susceptibility of buckwheat grains and products to the infestation by Trogoderma granarium Everts. The observations were conducted on three buckwheat cultivars: Hruszowska, Emka and Kora. The results suggest that buckwheat grains and products as suitable for the development of the first larval stages of Trogoderma granarium as wheat grain and wheat flour. However. extension of the development stage on buckwheat seems to indicate that the seed cover inhibits the capacity of larvae to feed on buckwheat.

The influence of bean seed surface lipids on infestation of seeds by Acanthoscelides obtectus Say was investigated. The experiments were performed in dual-choice bioassays on three bean varieties: Blanka, Bor and Longina. The collected data for natural and solvent washed seeds concerned the number of ovipositions, embryo mortality, lack of seed-boring activity, dead larvae inside seeds and developed insects. The results clearly indicated that bean seed surface lipids are involved in all infestation stages, and could be used to distinguish resistant and non-resistant varieties of been. Chemical analyses revealed the following groups of surface lipids: wax esters, long chain primary alcohols, n-alkanes, sterols, fatty acids, squalene, aldehydes, monoacylglycerols, ketones and fatty acid esters. Quantitative composition of surface lipids was analysed using selected chemometric procedures to determine correlation with bioactivity. Cluster analysis of surface lipid composition enabled to distinguish resistant and non-resistant varieties. Fatty acids and monoacylglycerols were found to deter bean weevil infestation, while alkan-1-ols acted as attractants.