مدیریت تلفیقی آفات

Integrated application of compatible methods is the most reliable strategy for sustainable management of phytophagous pests in different agroecosystems. In the current study, parasitism parameters of Trichogramma brassicae Bezdenko were determined on eggs of Tuta absoluta (Meyrick) reared on a susceptible "Infinity" and a resistant "Goldy" tomato cultivar. All experiments were carried out under laboratory conditions at 25 ± 1 °C, 65 ± 5% RH, and a photoperiod of 16:8 (L:D) h. Our results showed that the maximum number of parasitized hosts per parasitoid was 25.94 and 23 eggs in "Goldy" and "Infinity" cultivars, respectively. The cultivars tested had no significant effects on the net parasitism rate (C0), and the values of this parameter were 7.87 and 6.67 hosts on the mentioned cultivars, respectively. Similarly, the cultivar impact on the finite (ω ) and stable parasitism rates (ψ ) of T. brassicae was not significant. The parasitoid needed approximately one egg host to produce an egg on both cultivars for the simple reason that this parasitoid nearly always lays one egg in each host. In other words, the transformation rate (Qp) of the parasitoid on the "Goldy" did not differ from that estimated on the "Infinity". Our findings revealed that the resistant tomato cultivar, "Goldy", did not compromise T. brassicae-based biocontrol of T. absoluta. Therefore, these two control procedures could be combined for the integrated management of this pest.

Amblyseius swirskii Athias-Henriot (Acari: Phytoseiidae) is an important generalist predator used to control several important crops' pests such as spider mites, whiteflies, and thrips. In this study, the lethal concentrations of Mentha piperita L. (Lamiaceae) and Laurus nobilis L. (Lauraceae) essential oils (EOs) were calculated on the adult stage of the Frankliniella occidentalis (Pergande) (Thysanoptera: Thripidae). The side effects of EOs were investigated on the functional response of A. swirskii on F. occidentalis 1st instar larvae. The females of A. swirskii were exposed to sub-lethal concentrations (LC30 and LC50) of EOs for 12 h with the fumigant exposure method. In the control, the treatment was performed by using Triton X-100 (0.02). Treated predatory mites were selected randomly, and transferred to the experimental arenas containing 2, 4, 8, 16, 32, and 64 thrips. The predators were kept in the experimental arenas for 24 h at 25 ± 1 °C, 60 ± 10% RH, and a photoperiod of 16: 8 h (L: D). Results indicated that A. swirskii exhibited a type II functional response, regardless of EOs applications. The shortest (1.62 ± 0.046 h) and the longest (1.91 ± 0.049 h) handling times, were recorded in the control and the LC50 treatment of M. piperita EO, respectively. There was not a significant difference between attack rate coefficients (α) under sub-lethal concentrations. Based on the results, the two EOs have the potential to be used in F. occidentalis management, but their side effects on A. swirskii should be considered in IPM programs.

Biological control is a key component of Integrated Pest Management, however, the use of green lacewings as a biocontrol agent has not received much attention in Pakistan, although Chrysoperla carnea, a generalist predator against a variety of soft-sucking pests, has received much attention in Pakistan. Predatory insects always come out on top when it comes to biological pest control. In addition to minimizing losses caused by pests, applying biocontrol agents helps reduce the ecosystem from being affected by excessive chemical use. The present study proposes a new combination and confirms the newly recorded potential predatory species of green lacewings, Apertochrysa smitzi (Navás, 1914) comb. nov., found in Pakistan, belongs to the Apertochrysa venosa group based on male genitalia having gonocristae, which is only present in the A. venosa group. The diagnostic features of adult, as well as the photographs of dorsal habitus and genitalia, both male and female wings, and the complete life stages of A. smitzi are provided. We reared the larvae and adults of A. smitzi on the larval and nymphal stages of Sitotroga cerealella (Lepidoptera: Gelechiidae) and Pyrilla perpusilla (Hemiptera: Lophopidae), respectively, under controlled conditions. Apertochrysa smitzi is active most of the year and collected from sugarcane, wheat, and cotton crops from February to March, September and October. Both the larval stages and adults of A. smitzi were reared and released as a pest management tactic against various harmful sucking sugarcane insects for the first time in the Sindh province of Pakistan.

In Egypt, serious piercing-sucking pests such as the western flower thrips, Frankliniella occidentalis, white fly, Bemisia tabaci, the broad mite, Polyphagotarsonemus latus, and the two-spotted spider mite, Tetranychus urticae cause significant yield losses in sweet pepper crop grown in greenhouses. The purpose of this research is to assess the effectiveness of two phytoseiid mites, Amblyseius swirskii and Neoseiulus californicus, as biological control agents for piercing-sucking pests on sweet pepper in greenhouses, compared with chemical acaricides. Three release rates were assessed: 10 adults of A. swirskii/plant, 10 adults of N. californicus/plant, and 7 adults of A. swirskii + 7 adults of N. californicus combined. The highest population density of B. tabaci and F. occidentalis was on yellow ‘Qiuda’ followed by significant damage with T. urticae. Red ‘Grand bell’, on the contrary, was consistently more susceptible to T. urticae and moderately prone to whitefly infestation. Both biological and chemical pest control were efficient in reducing pest populations on sweet pepper in greenhouses. The results indicated that A. swirskii, alone or in combination with N. californicus, was more effective against F. occidentalis, B. tabaci, and P. latus on both pepper cultivars than acaricides sprayed under the same conditions. Moreover, the predatory mite, N. californicus, outperformed A. swirskii and acaricides against T. urticae. Together, the predatory mites, A. swirskii and N. californicus can improve biological control of piercing-sucking pests. The yield increased by 37.4 to 40.0% over the control treatment using the biological control candidates. Furthermore, biological control program resulted in the highest cost reductions for sweet pepper production (35.7–40.7 and 16.2–27.2%) compared to the control and acaricides treatments, as well as a safe yield free of chemical residues.

A few species of aphids are widespread and economically important in Iran's apple orchards. In this study, we looked for economical, environmentally friendly, and efficient management of aphids with particular emphasis on green apple aphid (GAA) Aphis pomi (de Geer). We aimed to avoid early-season pesticide applications, avoiding specific applications for aphid control and managing them via applications done against codling moth (CM), Cydia pomonella L., choosing suitable insecticide and dose to minimize side effects on prevalent natural enemies. Thus, CM was monitored by pheromone traps from mid-March in an apple orchard of the Agricultural Research Station of the University of Tabriz to determine the time of application based on degree days accumulated from a biofix. The number of GAA, rosy apple aphid (RAA), Dysaphis plantaginea Passerini, and their natural enemies were counted separately. It is known that GAA is the predominant aphid, and two species of ladybirds, Coccinella septempunctata (L.), and Hippodamia variegata (Goeze), are dominant species of the region. Acetamiprid was chosen as an effective insecticide against both CM and aphids. The lethal effects of this compound were studied on different stages of H. variegata and the last instar GAA. The orchard was divided into four plots, and each plot was assigned to a treatment including control, label dose (LD), ½ LD, and ¼ LD. Although LD killed 10% more GAA than ¼ LD, the damage intensity was 12-16% higher in the former. Considering economic benefits and reducing side effects on natural enemies, we recommend using ¼ LD of acetamiprid.

The Indian meal moth, Plodia interpunctella (Hubner), is one of the main economic pests of stored products, including dried figs, in Iran and the world. In this research, the effect of different doses of gamma radiation (50-1000 Gy) and temperature (20-35 ± 1 °C) was investigated on the life stages of P. interpunctella. The results showed that P. interpunctella eggs and adults exposed to gamma radiation (50 Gy) died after a short time. Therefore these stages are so sensitive to gamma radiation and were not used for further investigation on a combination of gamma radiation and temperature. In all temperatures, the survival period of larvae significantly decreased with increased radiation doses, especially at 600, 800, and 1000 Gy. Similarly, at 33 and 35 °C, low gamma radiation doses (50, 100, and 200 Gy) caused early larval mortality. In all temperatures, doses of 800 and 1000 Gy of gamma radiation resulted in 100% mortality of pupae; thereby, adult emergence declined to zero. However, in lower radiation doses of 50, 100, and 200 Gy and at 35 °C, the pupal mortality increased to 70, 70, and 83.33%, respectively. Results are promising for the integrated management of P. interpunctella on dried figs in storage.

Tuta absoluta is one of the most important pests of tomato in many countries. Emamectin benzoate (EB) is widely used in the control of lepidopteran pests, but there is sparse information available regarding its sublethal effects on T. absoluta. In this research, the lethal and sublethal effects of EB were investigated on T. absoluta under laboratory conditions. Acute toxicity bioassay was carried out on 2nd instar larvae using residue contact method. The LC50 value was 14.50 mg a.i. L−1, for 24 h exposure time. LC10 and LC30 of the insecticide was used for sublethal effect study. The insecticide significantly extended the larval developmental time at LC30. Pupal weight, fecundity and longevity of female adults were decreased at both tested concentrations. However, the LC10 and LC30 of the insecticide had no significant effects on pupal period, egg hatchability, and male adults’ longevity at sublethal effect study. These results suggest that the sublethal effects of EB might affect pest population dynamics significantly by delaying its development, and decreasing its reproduction. Hence, this bioinsecticide can be used in integrated pest management program of T. absoluta if its efficacy proven under the field and greenhouse conditions.