The sugar beet weevil (SBW), Bothynoderes punctiventris Germar, 1824, is a significant pest in most of Eastern Europe. Here, the SBW is described and its seasonal activity characterized, in terms of its different developmental stages in relation to Julian days (JDs), degree-day accumulations (DDAs), and precipitation, as a key to improving monitoring and forecasting of the pest. The phenology and population characteristics of SBW were investigated in sugar beet fields in eastern Croatia over a 4-year period (2012–2015). By using the degree-day model (lower development threshold of 5°C, no upper development threshold, biofix 1 January), the first emergence of overwintering adults was determined as becoming established when the DDA reached 20. The adult emergence was completed when the DDA reached 428. SBW males emerged first, following which the females dominated the adult population. Overwintering adults were present in the field until early July. In August, adults of the offspring generation began to appear. The eggs laid by the overwintering generation required, on average, 10–15 days to develop into larvae; however, eggs were found in soil samples over a period of 102 days (between JDs 112 and 214). Larvae were present in the soil samples over a period of a maximum of 143 days (the first larvae were established on JD 122 and the last one on JD 265), and pupae were established in the soil over a period of 102 days (between JDs 143 and 245). This study provides important data for understanding SBW population dynamics and developing potential population dynamic models for pest forecasting on a regional scale.

The deer ked (Lipoptena cervi) is a common ectoparasite of cervids. During the last decades the species has rapidly invaded in northern Europe, especially in Finland, towards the north and increased its prevalence on the moose population. Consequently, during this rapid invasion the deer ked has faced more severe climatic conditions. We studied whether pupal size (measured as pupal weight) and pupal development duration of the deer ked varies along historical invasion zones and temperature zones towards north in Finland. Moreover, we explored possible size- and gender-dependent variation in pupal development duration. We divided wild-collected pupae in respect to their origin in two ways: (1) temperature zones (from south-west to colder north-east) and (2) invasion history (from early to late establishment). We reared pupae in the controlled laboratory conditions in identical temperature and light conditions. Pupal size decreased towards north and the smaller pupae developed faster. However, the results do not show differences in pupal size or developmental characteristics between the invasion zones. This supports the idea of rapid developmental plasticity of the deer ked and that not the invasion history but the current temperature regime determines the life history of the deer ked when invading towards a colder environment.

We tested the effectiveness of volatile oils of Lippia adoensis Hoschst, Cymbopogon citratus (DC) Stapf., Eugenia uniflora L., Lantana camara L., and Chromolaena odorata (L.) King and Robinson at a dose range of 5 to 50 p.1 in protecting 9.9 g (50 seeds) of stored cow pea from infestation by the cowpea weevil, Callosobruchus maculatus F. The effectiveness of the oils as fumigants ranked as follows: L. adoensis > C. citratus > E. uniflora. Oils of L. camara and C. odorata were unsuitable for fumigation purposes. At doses of 5 to 20 μl, oil of L. adoensis protected cowpea from weevil attack. At 5 μl, volatile oil of L. adoensis was as effective as 20 μ1 each of E, uniflora and C. odorata, and only slightly inferior to C. citratus. Insecticidal activity of L. adoensis against C. maculatus was unequalled by any other oils tested. The effective doses of these oils did not impair the viability of treated cowpea.

Some aspects of the reproductive behaviour of the tossa jute defoliator, Acraea terpsicore (L.), were studied. The insect mated only once. A horny material was deposited on the female's genital aperture after mating. Mating began on the day of emergence and lasted for 7 days on 10% sucrose solution. Maximum number of matings was on the third day after emergence. Within the day, over 95% of matings was between 0600 and 1800 hr with a peak between 1200 and 1800 hr. Eggs were also laid mainly between 0600 and 1800 hr during the day with a peak between 1500 and 1800 hr. Oviposition which started on the day of emergence lasted for 7 days on 10% sucrose with a peak on the second day. The presence of the male, after mating had occurred, did not significantly affect the number of eggs laid. Adults emerged between 0600 and 1800 hr but mostly before mid-day. Peak emergence for males occurred earlier than that for females. Behavioural activities in courtship, mating, oviposition, and adult emergence, are described.

The efficacy of the powder and volatile oil of Piper guineense Schum & Thonn at protecting cowpea against seed beetle, Callosobruchus maculatus (F.) was tested in the laboratory. At low concentrations the powder significantly reduced oviposition and adult emergence while oviposition was completely suppressed at a higher concentration of 42%. The same concentration provided adequate protection for the same amount of cowpea placed in containers of different volumes. The powder, however, did not show any fumigant effect. Volatile oil at 0.002 and 0.005% significantly reduced oviposition and adult emergence, while oviposition was completely suppressed at 0.02% and above. Weight loss of seeds at 90 days after treatment with volatile oil decreased as concentration of the oil increased. The practical significance of the results in small scale storage of cowpea is discussed.

Sixty-four sorghum accessions were screened for resistance to the grain midge, Contarinia sorghicola Coq., under natural infestation conditions at Tamil Nadu Agricultural University, Coimbatore during 1982. Absolute resistance was not found in any of them. Low grain damage was recorded in PVK 50 (6.61%), PVK 55 (11.58%), AF 28 (17.03%) and DJ 6514 (17.05%) while the susceptible accession, SPV 234 recorded high grain damage (92.72%) in the screening trial. The ovipositional preference studies at insectary revealed significantly reduced grain damage in the resistant accessions. Among them, the lowest damage (8.33%) was recorded in PVK 50 followed by AF 28, DJ 6514 and PVK 55 while the susceptible accession, SPV 234 recorded 21.57% grain damage. In the choice experiments, SPV 234 had 11.22–35.36% more infestation than in the resistant accessions evaluated along with it. Studies on development and biology of the midge revealed that antibiosis is one of the mechanisms of resistance in the lines, PVK 50, DJ 6514, AF 28 and PVK 55.