At present, Acrobasis advenella (Zinck.) (Lepidoptera, Pyralidae) is the most dangerous pest of black chokeberry (Aronia melanocarpa [Michx.] Elliot). Damaged flower buds may decrease yield, while pest feeding inside fruits causes deterioration in their quality. The aim of the study was to determine and compare the effect of water and acetone plants extracts and essential oils using free choice tests of feeding site of larvae and oviposition of females. The following species were examined: Achillea millefolium, Cymbopogon citratus, Nepeta cataria, Origanum vulgare, Satureja hortensis, Tagetes patula nana, Tanacetum vulgare and Thymus vulgaris. The results showed that plant species had a significant influence on the choice of oviposition and feeding site of A. advenella. Moreover, the type of formulation affected the number of laid eggs. Females did not lay eggs on infructescences treated with acetone extracts. Among the test preparations, the highest percentage larvae and adults of A. advenella was recorded for plants soaked in C. citratus, and therefore it can be a potential attractant for this pest species. The lowest number of eggs and larvae was observed for T. vulgare.

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The study aimed at comparing the changes in the content of free amino acids, phenolic compounds and the activity of PAL and TAL caused by two piercingsucking arthropods: the grape mealybug (Pseudococcus maritimus Ehrh.) and the two-spotted spider mite (Tetranychus urticae Koch) in the leaves of orchid and strawberry, respectively. The obtained results show that the amino acid content and the ratio of amino acids to phenolic compounds increased in both plant species infested by the mealybug and the mite. However, such response was weakly dependent on changes in activity of the analysed enzymes. The pest feeding affected accumulation of the phenolic compounds, since the induction of the PAL activity in mealybug-infested orchid leaves during the first 5 h of the experiment preceded the increase in phenolic compounds during the first week of insect feeding. Instead, the increased activity of TAL was accompanied by elevated levels of phenolic compounds in the leaves of strawberry infested by mites. Mechanisms of biochemical plant responses induced by infestation of the studied herbivorous arthropods are discussed.

ABSTRACT. Acrobasis advenella is an oligophagous species feeding on plants of the Rosaceae family. The differences in concentrations of host plant quality components, above all primary metabolites and the presence or absence of secondary metabolites, directly affects herbivore growth and development. The objectives of this research were to determine the food preferences of 1 st instar larvae according to the chemical composition of host plants. The highest acceptance of rowan in the free choice test by 1 st instar larvae, as compared to hawthorn and black chokeberry, is positively influenced by the high content of total sugars and phenolic acids. The conclusion to be drawn from the results is that the differences in food choice by 1 st instar larvae feeding on fruits could have been due to the different chemical compositions of the fruit.