Aphids (Homoptera: Aphididae) on Winter Wheat: Predicting Maximum Abundance of Metopolophium dirhodum

In Central Europe, the most abundant aphid infesting the leaves of small grain cereals is Metopolophium dirhodum (Walker) (Homoptera: Aphididae). Annual variation in its seasonal dynamics was evaluated using a 25-yr series of standardized weekly censuses of winter wheat plots. M. dirhodum made up >50 % of the aphids on the foliage. Date of immigration (8 May–3 July), length of period of population increase (0–9 wk), and date of attaining maximum abundance (28 May–22 July) varied greatly. For the prediction, we regressed maximum numbers/tiller on numbers recorded in the first week after heading. The regression of maximum abundance on nonzero aphid counts revealed a critical number of ≥1.50 aphids/tiller, which if exceeded resulted in a harmful maximum abundance of ≥10 aphids/tiller at the peak. Zero aphid counts resulted in 10% of cases with a harmful maximum abundance. Using this regression for prediction will result in 18% of the recorded cases being false negatives and 9% false positives. Parallel annual variation in the average maximum numbers of M. dirhodum, Sitobion avenae (Fabricius) (Homoptera: Aphididae), and Rhopalosiphum padi (Linné) (Homoptera: Aphididae) indicated the following factors that affected their abundance: temperature in winter and host plant quality. The predictions apply only in areas where M. dirhodum is holocyclic and aphids do not overwinter in wheat stands

Ground beetles [Carabidae, Coleoptera] appearing in goats rue [Galega orientalis Lam.] cultivation

In 1997 and 1998, insects settling cultures of goats rue (Galega orientalis Lam.) at Mochełek were caught. Amongst ground beetles the dominating species were: Pterostichus melanarius III., Carabus auratus L., Harpalus rufipes De Geer, Harpalus aeneus F., and Bembidion lampros Hbst. and Harpalus frolichi Sturm. were subdominants.W latach 1997 i 1998 odławiano do pułapek Barbera owady zasiedlające uprawy rutwicy wschodniej (Galega orientalis Lam.) w Mochełku. Celem badań było poznanie składu gatunkowego fauny biegaczowatych. W laboratorium segregowano zebrany materiał faunistyczny, oddzielano biegaczowate i charakteryzowano pod względem liczebności odłowu oraz oznaczano gatunki. Spośród biegaczowatych gatunkami dominującymi były: Pterostichus melanarius III., Carabus auratus L., Harpalus rufipes De Geer, Harpalus aeneus F., a do subdominatów należały: Bembidion lampros Hbst. i Harpalus frolichi Sturn