The seasonal dynamics of the pea aphid, Acyrthosiphon pisum Harris, and entomopathogenic fungi from the order Entomophthorales attacking the aphid were analysed in alfalfa and field pea crops during the growing seasons of 1998 and 1999 at Nitra-Malanta. In both years, pea aphid populations on pea showed a pattern with one peak, culminated at flowering and pod formation. The infestation level on alfalfa was low in both years. Entomopathogenic fungi attacking the pea aphid were identified as Erynia neoaphidis Remaudičre and Hennebert and Conidiobolus obscurus (Hall and Dunn) Remaudičre and Keller. Both pathogens infected the aphid on pea, but only E. neoaphidis was found in the alfalfa plots. Infected aphids were not found on alfalfa during 1999. The maximum levels of infected aphids on pea were 10.30% and 48.39% in 1998 and 1999, respectively. During both years alate aphids were more frequently attacked than apteral ones. Correlation coefficients indicated a positive relationship between the number of infected aphids and precipitation, but this relationship was weak or moderately strong. A strong correlation was found between the number of dead aphids and number of alate aphids counted 5 to 10 days earlier.

Seasonal development of entomophthoralean unfection in colonies of \ud Diuraphis noxia\ud and \ud Rhopalosiphum maidis\ud was evalauted on summer barley under conditions of south-western Slovakia in 2001 and 2002. \ud D. noxia\ud was infesting summer barley during both years, while \ud R. maidis\ud was only recorded in 2002. Further three cereal aphids, \ud Rhopalosiphum padi\ud , \ud Metopolophium dirhodum\ud and \ud Sitobion avenae\ud , were also observed on summer barley. Complex of entomophthoralean fungi identified in cereal aphid colonies included four species, \ud Pandora neoaphidis\ud , \ud Entomophthora planchoniana\ud , \ud Conidiobolus obscurus\ud and \ud Neozygites fresenii\ud , with \ud P. neoaphidis\ud as the most prevalent fungus during both years. Two parasitic fungi, \ud P. neoaphidis\ud and \ud E. planchoniana\ud , were identified from \ud D. noxia\ud , but \ud P. neoaphidis\ud was predominant. Infection rate in \ud D. noxia\ud colonies was low, not exceeding 15% and 10% in 2001 and 2002, respectively. Only nine \ud R. maidis\ud individuals were killed with entomophthoralean fungi. The fungi were identified as \ud P. neoaphidis\ud and \ud C. obscurus\ud . No epizootics were observed in the aphid colonies. The fungi could not control development of the aphid populations since they did not appear until high host densities had been established in the crops

Melanagromyza albocilia Hendel, a stem borer of field bindweed (Convolvulus arvensis) was observed at three sites in Slovakia during 1999 and 2000. The insect overwintered as pupa. The first generation adults emerged in May and those of second during June—August. Percentage of infested field bindweed plants varied from 46.7% to 99.2% and number of infested stems from 4.1% to 37.2%. Infested stems contained an average of 0.84 ± 0.40 to 1.34 ± 0.50 specimens (larvae, parasitized larvae, pupae). The population of M. albocilia was the highest in 1999, with mean densities of 1.57 ± 1.01 to 3.21 ± 2.13 specimens/plant. All parasitoids emerged from larvae were identified as Bracon picticornis Wesmael.