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The fecundity, reproductive rate, and survival of Lysiphlebia mirzai parasitising third instar nymphs of the cereal aphid Rhopalosiphum maidis were measured at six different host densities under constant laboratory conditions. The survival rate (lx) of the female parasitoids was unaffected by host density, with an average adult life‐span of 5–6 days at all densities. The age‐specific fecundity rate (mx) was host density‐dependent. The value of mx decreased rapidly from the first day of parasitisation. The number of hosts available determined the maximum possible number of mummies. At 200 hosts available per day, the average fecundity was 184.6 mummies/female; the maximum number of mummies yielded by any female was 200. The relationship between host density and the number of aphids parasitised per female was linear at ≤50 aphids/cage/day, but at higher host densities (≥100 aphids/cage/day) a significant curvilinear regression was observed. The intrinsic rate of natural increase (rm) increased with increasing host density. Maximum value of rm (0.262) was obtained at a host density of 200. The response of rm to changes in host density and parasitoid sex ratio is shown. A typical type II functional response was observed for L. mirzai. The curve was described by a logistic curve, Np = 200/[1 + exp(5.65 − 1.60 ln No)]. The search rate of the parasitoid was inverse host density‐dependent. No significant variation in the sex ratio of F1 offspring was observed at different initial host densities. Sex ratio values exceeded 0.5 at all host densities. The results evaluated the reproductive potential of L. mirzai as a promising biological control agent.

A life-table was constructed for a little known aphidiid wasp Lysiphlebia mirzai, a parasitoid of cereal aphid, Rhopalosiphum maidis. The female parasitoid survived 6.4 + 1.17 (SD) days and oviposited intensively 4.0 +_. 0.47 days. The total fecundity rate, Rt, was 169.2 + 6.94 mummies/female and net reproductive rate, Ro, was 92.70 female offspring/female. The intrinsic total fecundity rate, rt, and intrinsic rate of natural increase, rm, the finite rate of total fecundity, At, and finite rate of increase, 2~, was 0.27048, 0.24155, 1.31059 and 1.27322 respectively. The mean generation time (18.75 days) and doubling time of the population (2.87 days) was slightly higher than other aphidiids studied so far. The proportion of female progenies decreased significantly on the successive oviposition days.

The study of the air-spora in the Central Library of Gorakhpur University indicated the presence of 19 different types of fungal spores. Amongst these Aspergillus niger, A.flavus, Cladosporium spp., Curvularia spp., Paecilomyces sp., Penicillium spp., and periconia sp. were more than 80.5% followed by species of Absidia, Alternaria, Chaetomium, Mucor, Rhizopus, Trichophyton, and Cercospora. Fungal spores showed time trends during the study period. The fungal spore concentrations gradually increased from July to September and attained their maximum in September to October and thereafter decreased. Besides fungal spores, small pieces of paper, dust particles and insect derivatives loaded with fungal mycelium and bacterium were also observed throughout the investigation period.Water, Air, and Soil Pollution 34 (1987) 125-134.

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