Data on the biology of Phyllotreta vittula (Redtenbacher, 1849) (Coleoptera: Chrysomelidae: Alticinae)

The biology of Phyllotreta vittula (Redtenbacher, 1849) was studied both in the laboratory and under field conditions in Western Hungary. Adults overwinter under plant debris or in the upper layer of the soil and appear by the end of March-beginning of April. The egg-laying period begins mid-May. As a result of prolonged egg-laying, ail three larval instars may be present simultaneously during the vegetative period. The pupation lasts until October. Young adults of the new generation appear in August and retire to the overwintering sites by the end of October. There is one generation per year under Hungarian conditions. The mean number of eggs deposited under laboratory conditions was 71.91+/-11.6. Incubation period averages 4 days under 28 degrees C+/-0.8 degrees C, 6 days under 23 degrees C+/-1.1 degrees C and 11 days under 18 degrees C+/-0.7 degrees C. The highest mortality (average 25 %) was observed under 18 degrees C. the lowest one (average 8 %) under 23 degrees C. The larval development averages 15-18 days, praepupal stage averages 3-5 days, while pupal stage 14-16 days at 23 degrees C in thermostat chamber. Due to the imperfect laboratory rearing methods, data on the larval and pupal development are informative.