https://apm.uma.ac.ir/ Agricultural Pest Management en daily 1 Thu, 23 Jul 2015 00:00:00 +0430 Thu, 23 Jul 2015 00:00:00 +0430 https://apm.uma.ac.ir/article_305.html The tomato leaf miner, Tuta absoluta (Meyrick) (Lepidoptera: Gelechiidae), is a major pest of tomato, both in greenhouse and open field crops. The population fluctuation of this pest was studied with pheromone traps in four different fields located in Boroujerd County, Lorestan Province during 2013-2014. The results showed that this pest had six and seven generations in 2013 and 2014, respectively. The first individuals of T. absoluta were captured on 8th May, 2013. The highest density of T. absoluta in 2013 was observed on 7th of August with 125.75±38.5 individuals/trap. The average number of captured moth during 75 sampling times was 1947.75±265 individuals for each trap. In 2014, the first individuals of the moth were captured on 10th of May and the peak of the population density was observed on 2th of August with 110.33±11.5 individuals/trap. The average number of moth in 2014 was less than the previous year, with 1742.33±109 individuals for each trap. The use of reported physiological time for this pest certified the efficiency of pheromone traps to estimate the population fluctuation of T. absoluta. Correlation between the captured moth and temperature showed a significant and positive correlation between them in both years. The finding of this study is arguably the first piece of information on the population dynamic of this pest in field condition in Iran which showed that T. absoluta had high potential to damage tomato in Boroujerd County. Also this study showed that the pheromone traps as reliable tools can be used in determination of the population fluctuation of this pest. https://apm.uma.ac.ir/article_306.html Trichogramma brassicae Bezdenko is one of the most important egg parasitoid that is released for controlling Helicoverpa armigera (Hübner) in crop fields of Golestan, Mazandaran and Ardebil provinces of Iran. This parasitoid has potential to reduce the pest in agricultural ecosystems. The parasitoid was reared on the eggs of grain moth, Sitotroga cerealella Oliv. (Lep.: Gelechidae) eggs at 26±1℃, 70±5% RH and a photoperiod of 16:8 (L:D) h. The pupal stage of the parasitoid was exposed to the insecticide solutions using dipping method. In this study, sublethal effects of emamectin benzoate and methoxyfenozid were evaluated on the life table and reproduction parameters of T. brassicae. The survivorship was affected by the insecticides. The maximum and minimum of life expectancy was observed in the control and emamectin, respectively. The maximum life span of females was estimated to be 19, 18 and 17 days in the control, methoxyfenozid and emamectin benzoate, respectively. The highest net fertility rate was recorded in the control (86.84 eggs) and the lowest value was observed in the emamectin treatment (23 eggs). Semi field and field studies aiming to assess efficacy of combined use of insecticides and T. brassicae is needed to obtain more applicable results. https://apm.uma.ac.ir/article_307.html The onion thrips, Thrips tabaci (Lind.), is a pests of potato, Solanum tuberosum L. Orius niger Wolff is an important predator of this pest in Iran. In this study, we investigated the population densities of T. tabaci and O. niger on seven potato genotypes namely Agria, Savalan, Morene, Kondor, Diamant, PI397082-2, and PI397097-2 under field conditions during 2011 and 2012. In this study, the lowest thrips densities were observed on Savalan cultivar, in both years. Moreover, the density of predatory bug on Savalan was significantly higher than the other tested genotypes. In addition, amongst the six tested growth stages of potato, the highest density of predatory bug was observed on flowering stage of the seven tested genotypes. Our results suggest that Savalan cultivar is most suitable for predatory activity of O. niger amongst tested genotypes of potato; therefore cultivation of Savalan integrated with O. niger could provide effective and sustainable management of T. tabaci in the region. https://apm.uma.ac.ir/article_308.html The gypsy moth, Lymantria dispar, is one of the most devastating forest tree defoliator pests in different parts of the world. The gypsy moth is distributed in different regions in Iran especially in the northern and north-western provinces of the country. Young larvae feed primarily on some preferred host trees such as oaks, willows and alder, but older larvae can feed on over 500 species of trees and shrubs. The pest feeds on leaves of at least 32 species of trees and shrubsin Arasbaran. It actively feeds on plant foliages from mid-spring to early summer, till develops into a pupa. The study was conducted to determine natural enemies of gypsy moth in Arasbaran forests by field and laboratory studies from 2002 to 2008. The results showed that following pest control agents are parasitized eggs, larvae and pupa of the pest.   1) Monodontomerus aerus Walker (Hymenoptera: Torymidae) 2) Tachina praeceps Meigen (Diptera: Tachinidae) 3) Zenillia libatrix Panzer (Diptera: Tachinidae) 4) Brachymeria intermedia Nees (Hymenoptera: Chalcididae) 5) Glyptapanteles indiensis Marsh. (Hymenoptera: Braconidae) 6) Glyptapanteles porthetriae Mues. (Hymenoptera: Braconidae) 7) Hexamermis albicans (Nematoda: Mermithidae) 8) Calosoma sp. (Coleoptera: Carabidae) 9) Araneus diadematus (Aranea: Araneidae) 10) Cheiracanthium punctorium (Aranea: clubionidae) 11) Nuclear polyhedrosis virus (NPV) 12) Birds and rodents https://apm.uma.ac.ir/article_309.html The tomato leafminer, Tuta absoluta (Meyrick) (Lepidoptera:Gelechiidae), is one of the Key pests of tomato. It may potentially damages 30-100 percent of the tomato yield under non controlled condition. Additionally it may damage to other solaneceous plants. In this study, we examined the development and population growth parameters of T. absoluta on three solanecous plants including two (AGRIA and FONTANA) potato cultivars and (HAN-RAN) tomato cultivar using cut leaves of the hosts under laboratory conditions. Insects were reared on the hosts for two generations before starting of the experiments. Eggs were placed in the petri dishes on the leaves of each host plants in 65 replications. The experiment carried out under laboratory conditions 25±5 ° C, 60±5% relative humidity and 16:8 h L:D photoperiod. Resulted data were analyzed using two sex age-stage life table program. Results showed that the eggs incubation period was shorter for the insects reared on AGRIA potato cultivar while the larval and pupal developmental time was shorter on FONTANA potato cultivar rather than other host. The highest and lowest mean generation time, finite rate of increase, gross reproduction rate, and intrinsic rate of increase were observed for insects fed onHAN-RAN tomatocultivar and AGRIA potato cultivar respectively, despite the mean comparison indicated no significant differences. Although the results showed that tomato was a more suitable host-plant and possessed better nutritional quality rather than potato, the potential population increases noticeably when T. absoluta fed on potato. Furthermore, T. absoluta may deserves a potential pest for the potato crop under appropriate climatic conditions and under temporospatial coincidence of the crop and pest. https://apm.uma.ac.ir/article_310.html In this study, the functional and numerical responses of Nephus arcuatus Kapur, one of the most important predators of Nipaecoccus viridis (Newstead), were investigated. N. viridis egg densities (2, 4, 8, 15, 40, 65, 90 and 115) were individually presented to a single mated female (3 days old). The prey densities were replaced every day for 33 days. The functional response was determined using logistic regression and the parameters were estimated by non-linear regression. The results revealed type III functional response of N. arcuatus. Constant coefficient (b) and handling time (Th) were estimated to be 0.00505 and 0.4163 h, respectively. The maximum theoretical predation rate (T/Th) was calculated as 57.7 eggs. The reproductive numerical response, in terms of egg laid increased curvilinearly with prey density and females laid 1 and 229.5 eggs at densities of 4 and 115, respectively. In contrast, the food exploitation efficiency was decreased with increasing of prey density. The similar shapes of both functional and numerical responses indicated that both were linked and that they function simultaneously. According to the obtained results, a ratio 1:115 (predator: prey) could be probably provided with an effective control, when releasing this predator for biological control of N. viridis.