نشریه مهار زیستی در گیاه پزشکی
سال هفتم شماره 1 (بهار و تابستان 1398)

Some bio-ecological studies were carried out on the syrphid flies in several agro-ecosystems in temperate regions of Kermanshah province during 2013-16. Fifteen aphidophagus syrphid species were identified which Eupeodes corollae was the dominant species. For Evenness index, the highest value was belonged to irrigated wheat and the lowest one was belonged to stone fruit orchards, which were evaluated as 0.72 and 0.25, respectively. In biennial calculation of the Margalef index, rain-fed wheat and canola have the lowest and highest values of this index which were evaluated as 4.77 and 11.83, respectively. For Sorenson similarity in first year, the highest and lowest degree of similarity was belonged to apple-stone fruits and apple-canola with values of 0.88 and 0.5, respectively. In the first year, Shannon- Wiener index for apple trees, irrigated wheat, canola, stone fruit trees and rain-fed wheat, were determined as 1.42, 1.41, 1.18, 1.07 and 1.01, respectively. In the following year, these indices were evaluated for irrigated wheat, canola, apple and stone fruit trees were evaluated as 1.49, 1.28, 1.48 and 0.86, respectively. The high Shannon-Wiener index indicated the greater diversity of species based on the number of species variance analysis of this factor using t student test revealed that all of the agroecosystems have an identical species diversity (P> 0.05) The evaluated agroecosystems have an appropriate biodiversity of syrfid predator flies and this biodiversity is a key to their sustainability and survivor.

The aim of this study was to evaluate toxic and synergistic effects of ecdysoids compounds and diatomaceous earth on their integrated control along with the entomopathogenic fungus, Metarhizium anisopliae on date palm horned beetle larvae. In this study, the evaluated ecdysoids were Atabron, Dimilinand Nimazol. The fungal mycelium growth and spore germination were evaluated to checking the consistency of the ecdysoids compounds by extract medium mixing method. Then, the toxicity of compounds individually and in conjunction with pathogen M. anisopliae was evaluated by bioassay method. Studies revealed that mycelial growth and spore germination of M. anisopliae occurre in all ecdysoids compounds. The highest compatible index was 76.89 for concentration of 500 microliters per liter of Nimazol extract and the lowest level consistent with the incorporation of Dimilin in 1000 microliters per liter concentration. The combination of ecdysoids compounds with fungal pathogen M. anisopliae had synergistic effect on larval developmental stage of date palm horned beetle. The synergistic effect of Nimazol was higher. The use of diatomaceous earth showed mortality of horned beetle larvae with average lethal concentration equal to 1269.7 mg per liter. It also has synergistic effects on toxicity of fungal pathogen M. anisopliae and anti-synthesis chitin componds. The most powerful synergistic effects were observed in terms of mixing 50 percent lethal concentrations of diatomaceous earth, Nimazole and M. anisopliae.

The predatory bug, Andrallus spinidens (F.) is one of the most important biological control agents of lepidopteran pests in rice fields of Iran. An experiment was conducted to evaluate the effects of six recommendedpesticides (including 3 insecticides, 2 fungicides and 1 herbicide) on A. spinidens thorough a completely randomized design (CRD) replicated 6 times. The ingestion method was performed on the 4th–instar nymphs of the predator. Pesticides concentration were prepared based on the field recommended doses. Distilled water was used as the control. Newly emerged 4th instar nymphs provided with 2–ml of pesticides inside small containers for 24 hours. Thereafter, the survived nymphs were provided with distilled water and 2–3 last instar larvae of Galleria mellonella. The experiments were carried out under laboratory conditions at 25±0.5 °C, 70±5% RH and a photoperiod of 16:8 h (L: D). Mortality was recorded daily until the adult emergence. The results revealed that maximum reduction in fecundity of A. spinidens occurred in Fipronil, Diazinon and Malathion treatments and the minimum reduction was observed in Pretilachlor treatment compared with that of control. Based on the total effect of IOBC classification, Fipronil, Diazinon and Malathion insecticides with 100% mortality were placed in the class 4 (harmful). Similarly, E+C and Tricyclazol fungicides were grouped in class 3 (Moderately harmful) with 86.84% and 91.58% total effect, respectively. Pretilachlor herbicide, with 74.39% mortality was placed in category 2 (slightly offensive). Therefore, if field results are confirmed, studied insecticides are not suitable candidates for integrated pest management programs in rice when the predator is active.

Concerning the adverse effects of the indiscriminate use of chemical pesticides on the environment and human health, today, biopesticides as a safe and effective alternative are necessary for pest control in sustainable agriculture programs. The biopesticides discuss here is restricted to the products containing live microorganisms. Although, the considerable number of effective biocontrol strains have been identified, but one of the main reason in their unsuccessful commercialization is thelack of suitable formulation. There are many scientific and technical challenges in the process of biopesticide formulation. Nevertheless, due to technological advances and new social outlook toward safe food and environment, biopesticide market is growing and it is predicted that its share increases in the near future. In this review, we present an introduction about the necessity of the biopesticides application as a proper alternative to chemical pesticides and their role in modern agriculture. Then, we discuss general challenges in production, formulation and commercialization of microbial-based biopesticides. The procedures before formulation including selecting the effective strains and their preservation as well as the fermentation methods were briefly described. After that, the two types of formulation i.e. liquid and solid, their advantages and disadvantage, a various ranges of carriers and adjuvants and important environmental factors affecting the formulations were also outlined. Finally, different types of common formulation were separately introduced and exemplified.

Fungus gnat, Lycoreilla auripila Winnertz, 1867 (Dip.: Sciaridae) has been considered as one of the most serious threat of cultivated mushrooms, which extensive sprayings against it occur each year. In this study, the age-stage two sex life table of A. coriaria feed on second instar larvae of  L. auripila and D. melanogaster were studied at 25±1°C, 60 ± 10% R.H. and a photoperiod of 16: 8 (L: D) hrs. According to obtained results, the net reproduction rate (R0) were 9.475 ± 1.459, 7.812 ± 1.292 offsprings and intrinsic rate of increase (r) were reported as 0.059 ± 0.004, 0.052 ± 0.004 day -1 on second instar larvae ofL. auripila and  D. melanogaster, respectively. Population simulation based on the age-stage two- sex life table showed the age structure of A. coriaria and high growth rate of this predator on both prey types. As the first study of the A. coriaria life table feed on L. auripila and D. melanogaster, it contributes to show the potential and importance of this predator in mushroom production. Additionally, it stressed that common fruit fly larvae could be used as a factitious prey for development and reproduction of A. coriaria.

Waterferns have caused many problems in aquatic ecosystems and rice fields of northern regions during recent decades. Despite the fact that Azolla spp. are known as one of the most important invasive species worldwide, with management and applying biological control agents in natural habitats they can be used as beneficial species. For Azolla management, it is very important to have enough knowledge about the reproduction, substantial conditions for invasion and biological control agents of the plant in the area. . In northern regions favorable environmental conditions such as high humidity, suitable temperature, absence of specific natural enemies and etc, caused Azolla spp. expansion and invasion. In recent years, it has been demonstrated that some of the native and migratory species such as Cataclysta lemnata, Nomophila noctuella, Diasemiopsis ramburialis and Rhopalosiphum nymphaeae feed on Azolla spp. in the area and have high dispersal. Recently, exotic weevil, Stenopelmus rufinasus, has been recorded in the area as well. Studies indicated that C. lemnata and S. rufinasus as biological control agents and other species as biotic resistance factors can be used for Azolla spp. management in northern regions. According to these findings and existing knowledge we have enough resources to control Azolla, and by providing of the necessary facilities it can be controlled in northern regions of Iran.

The mealybug destroyer, Cryptoleamus montrouzieri Mulsant is known as the most effective biological control agent of the mealybugs. The effect of temperature on developmental rate of C. montrouzieri was studied. Developmental times of incubation period, larval, pupal, and overall immature stages of the mealybug destroyer were recoreded at temperatures ranging 15–35°C, 50–60% RH, and a photoperiod of (L:D) 16:8h. According to the ANOVA, temperature affected significantly developmental time of the mealybug destroyer at 1% of probability level and increasing temperature lead to decreasing developmental time. In order to describe temperature–dependent development and to estmate related thermal indices, developmental rate of C. montrouzieri modeled as a function of temperature using mathematical models. The results showed Briere–2 and Lactin non–linear models had the best performance to predict developmental rate of C. montrouzieri in the studied temperature range. According to the non–linear models, thermal tolerance for development of the overall immature stages of the mealybug destroyer was 10.40–33.56°C and optimal temperature was 30.08°C. Obtained results can be used for improving environmental conditions of the mealybug destroyer mass rearing instectariums and biological control programs.

It has been three decades since the introducing of Phytoseiulus persimilis A.H. from the Netherland to Iran in 1987 for biological control of spider mites. First mass releasing predatory mite evaluated on Tetranychus turkestani of cotton and soybean plants in Golestan province, mungbean and eggplants in Manojhan in the southern part of Kerman province with satisfactory results. P. persimilis released on bean plant infested by Tetranychus urticae in Markazi and Charmahal–Baghtiari provinces failed due to higher temperature and lower relative humidity. Releasing one predatory mite to 10 spider mites in greenhouse cucumber under the mean of 25°C during middle March to the early month of May provided biological control in Varamin region. Both P. persimilis and Nesoseiulus californicus releasing at lower spider mites incidence in greenhouse cucumber and providing more than 50% humidity during hot spring and summer months led to biological control during the harvesting period. Greenhouse strawberry spider mites control by predator failed in Hashtgerd region due to the underside of leaf contained higher trichoms density. While greenhouse carnation and roses plant infested by spider mites controlled by this predatory mite effectively in Mahalat and Esfahan region, respectively. Studies side effects of synthetic and botanical acaricides on this predator mite revealed that few are less hazardous and can be applied for integrated management. Cost of mass rearing of P. persimilis on infested bean plants by spider mites can save expenses up to 80% as compared to imported and greenhouse cucumber production free from hazardous acaricide became available.

The initial step to mass production and commercialization of native entomopathogenic fungal isolates includes collection as well as evaluation of their pathogenesis on the pest. This research aims to investigate the pathogenicity of 36 local fungal isolates collected from the Iranian Research Institute of Plant Protection, Tehran, Iran against greenhouse whitefly Trialeurodes vaporariorum. Due to the variation of the collected isolates volume, a preliminary screening test carried out on the fourth instars of a model insect Galleria mellonella. Based on the obtained results, the Beauveria bassiana A1–1 isolate showed the highest mortality with an average of 75%, followed by IRAN1787C, IRAN1751C, IRAN1395C, IRAN428C and IRAN441C with mean mortality rates of 57.50, 55, 52.50, 50 and 45%, respectively. Subsequently, the isolates were selected for evaluation of vegetative growth, sporulation and bioassay tests on greenhouse whitefly. In the bioassay test, five concentrations of the isolates (104, 105, 106, 107 and 108 conidia/ml) were tested on the third–instar of whitefly nymphs, and then the parameters LC50 and LT50 of the isolates were calculated. The highest vegetative growth rate belonged to IRAN428C, IRAN1395C, A1–1, IRAN1787C, IRAN441C and IRAN1751C isolates while the highest sporulation rate belonged to IRAN1787C, A1–1, IRAN428C, IRAN1395C, IRAN441C and IRAN1751C, respectively. The results showed that the A1–1 isolate indicated the lowest LC50 and LT50 values among all used concentrations. Moreover, its vegetative growth and sporulation ranked third and second among all the collected isolates, respectively. Therefore, the A1–1 isolate is being introduced as the most effective biocontrol agent to control greenhouse whitefly.

The Egyptian cotton leafworm is a polyphagous pest with a broad range of hosts causing annually significant damage to agricultural crops. It has been found that no all strain of Bacillus thuringiesis are effective on this pest and small numbers of the isolates are effective due to the contents of their crystalline proteins. The aim of the present study was to obtain native isolates of Bt that were capable of controlling and investigate the effect of growth medium of Bt on the insecticidal ability of selected isolates. Hence, the pathogenicity of 118 native isolates of B. thuringiesis cultivated in R2NB medium were determined on five–day–old larvae of Spodptera.littoralis at 27 °C on artificial diet. The mortality rate of 118 native isolates of Bt with a concentration of 103 spore ml–1 illustrated that the highest mortality rates belong to four isolates GON–9, QM–2, GN–13 and QM–1 with 93.33, 70, 46.67 and 43.43, respectively. In addition, GN–12, EN–2, GON–7, CHI–2, AGI–7, AGI–3 and AGI–2 isolates were ineffective on S. littoralis larvae. Then, the effective isolates grown in nutrient broth and R2NB medium were evaluated on mentioned pest. The results showed that the four selected isolates were more lethal on R2NB medium than NB on larvae of Egyptian cotton leafworm and their differences were significant. Also, the content of cry genes particularly cry 2Ab in effective isolates were examined and traced. The outcomes of polymerase chain reaction demonstrated QM–1, QM–2 and GON–9 have cry 2Ab.

The present study was performed to evaluation of the toxicity effects of Bacillus thuringiensis var. kurstaki, thiacloprid and diatomaceous earth on 2nd and 3rd larval instars of large white butterfly (Pieris brassicae) in the single or combination form under laboratory conditions. The LC50 values by probit analysis resulting from the effects of different concentrations of B. thuringiensis, thiacloprid and diatomaceous earth at 48 and 72 hours on the 2nd and 3rd larval instars, respectively for B. thuringiensis (1593.5 & 991.8), (1800 & 1150.9) ppm, for thiocloprid (4933.3 & 2705.9), (5208.6 & 2878.3) ppm and for diatomaceous earth (340.9 & 216.6), (386 & 254.9) mg/L were obtained. The result showed that in both larval instars the mixing of factors had an increasing effect compared to the separate effects of each, so that the average mortality in 48 and 72 hours on 2nd and 3rd instars larvae, respectively, (70 & 76.7) and (66.7 & 73.4) were reported. Based on laboratory bioassays, mixing of thiocloprid, diatomaceous earth with B. thuringiensis for integrated pest management is recommended.

In this research, during the years 2012-2013 the identification, distribution and efficacy of egg parasitoid, Ooencyrtus ferdowsii on rosaceous long horn beetle, Osphranteria caerolescens have been studied in infected almond gardens in Ferdows (Kharv, Fath-Abad and Mahvid), Sarayan (Karimou, Mosabi and Nodeh) and Qayen (Korghond And Kalateh Seri) in Khorasan-Jonoubi province, Iran during 2012-2013. O. ferdowsii has been active in the region between late June and mid-June. The time for the start of activity was in late June and the last time the wasp was seen in mid-May in Mahwid. In the areas of Ayask, Kalateh Series and Islamiyah, this parasitoid was not detected in sampling. The average percentage of parasitism in all sampling areas was 34.5%. Most parasitism was recorded on July 7, 2013 in total areas with 79.7%. Parasitism was a type of super parasitism. The highest sex ratio (females to total wasps) was recorded 85.7% and the mean was about 67%. This parasitoid indicates the high potential for controlling the rosaceous long horn beetle.