jafar ebrahimifar

In current study, pathogenicity of two pathogenic fungi, Beauveria bassiana Vuellemin and Metarhizium anisopliae Sorokin were assessed on adults of elm leaf beetle, Xanthogaleruca luteola with four concentrations 105, 106, 107 and 108 spore/ml and control treatment using immersion and spraying methods. The experiments were conducted at controllable conditions, 25±1°C, 75±5% RH and photoperiod 12:12 h in growth chamber. Mortality rate in both methods in all treatments were recorded during 10 days. The values of LC50 and LC90 for B. bassiana were 2.7×106 and 7.72×106 spore/ml in immersion method and were 7.75×106 and 35.05×106 spore/ml in spraying method while these values for M. anisopliae were 2.68×106 and 7.99×106 spore/ml in immersion method and were 8.36×106 and 46.8×106 spore/ml in spraying method, respectively, it shown higher pathogenicity of B. bassiana in comparison with M. anisopliae. The lowest LT50 and LT90 for B. bassiana at concentration 108 spore/ml were 3.39 and 13.12 days while these values for M. anisopliae were 4.51 and 15.03 days respectively. The result shows that B. bassiana in both methods immersion and spraying causes more mortality during shorter time compare to M. anisopliae. According to findings of the current study, both fungi B. bassiana and M. anisopliae can be used in integration with other non-chemicals method for control of elm leaf beetle.

The greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hem., Aleyrodidae) is a cosmopolitan and polyphagous insect that attack a wide range of crops. In this study, the biological parameters of parasitoid wasp, Eretmocerus delhiensis Mani (Hym., Aphelinidae) on T. vaporariorum were evaluated. The experiments were conducted at 25±1°C, 65±5% RH and a photoperiod of 16: 8 h (L: D) in growth chamber. Based on the results of our studies, all of parasitoid progeny were female and there was no male progeny. Adult emergence, pre-oviposition, oviposition and post-oviposition period, developmental time and longevity of female parasitoid were 71 %, 15.03±0.32, 0.46±0.06, 4.2±0.12, 1.04±0.08, and 5.71±0.13 and 20.74±0.5 days, respectively. Also, other parameters such as; daily fecundity, total fecundity, daily host feeding, and total host feeding were 3.04±0.11 and 17.43±0.17 eggs 1.07±0.05, and 6.40±0.35 nymphs, respectively. Regression analysis revealed that host feeding had a significant effect on oviposition of this parasitoid. Therefore, the parasitoid wasp E. delhiensis not only parasitize their hosts but also kill them through host feeding. These results suggest E. delhiensis has the potential to be used as a biological control agent in greenhouse whitefly management.

The greenhouse whitefly, Trialeurodes vaporariorum Westwood (Hem.: Aleyrodidae) is a polyphagous and key pest that causes damaging to wide range of crops. The parasitoid wasp, Eretmocerus delhiensis Mani (Hym.: Aphelinidae) is a syn-ovigenic and thelytokous species that parasitizing greenhouse whitefly nymphs. In order to evaluation parasitoid wasp, Eretmocerus delhiensis Mani (Hym.: Aphelinidae) in control of greenhouse whitefly demography parameters of E. delhiensis on greenhouse whitefly on tomato cultivar Super-Chief at temperature 25±1°C, 65±5 % RH and a photoperiod 16:8 h (L: D) in growth chamber were studied. For calculation of population growth parameters Age- Stage, Two-Sex Life table was used. The result showed that oviposition period, longevity and fecundity for this parasitoid were 4.2±0.12 d, 20.74±0.5 d and 17.43±0.17 offspring respectively. Based on results of the life table, demography parameters consisting of net reproductive rate (R0), gross reproductive rate (GRR) were 12.11±0.94 and 31.43±1.85 offspring per female, intrinsic rate of increase (rm), finite rate of increase (λ), were 0.16±0.0059 d-1, 1.17±.007 d-1 and mean generation time (T) and doubling time (DT) of E. delhiensis were 15.66 d and 4.354/d respectively. Based on our results, this parasitoid is a promising candidate for greenhouse whitefly control.