s. aramideh

The greatest damage to hazelnut is due to its pests. Filbert aphid Myzocallis coryli is one of the important pests of this tree. In order to reduce the population of hazelnut aphids, which causes severe damage to this plant, the use of biological control method based on insect pathogenic fungi in laboratory and field conditions is purposed. In this study, the effects of four isolates DEMI001, IRAN 715C, M14, V245 of M. anisopliae were used and evaluated on the second instar nymphs in laboratory (25±1 °C, 65±5% relative humidity and photoperiod 16: 8 hours dark: light) and field conditions (30±3 °C, 55±6% relative humidity and photoperiod 14:10 dark hours: Ligh). In order to evaluate the effects of four isolates from the lethal concentration for 50% of the population (LC50) probit analyses program of SPSS-21 software was used. The LC50 value achieved from the effect of, IRAN 715C, DEMI001, M14 and V245 isolates on the second instar nymphs of the aphid in laboratory and field conditions were 5. 13 ×107, 3.00 ×106, 3 . 09 ×107, 1.11 ×106 (spores/ml) and 5. 03 ×107, 1.81 ×106, 0.43 ×106, 1.5×106 (spores/ml), respectively. The results of this study showed that the isolate M14 is more effective on the second instar nymphs of this aphid. Also, for controlling the aphids’ nymphs in field conditions, a higher concentration of fungal suspension is required compared to experimental conditions. In evaluate interaction between two isolates additive or synergistic effect was not observed.

In the present study, the effect of hexytiazox, nano sulfur, alginate/sulfur (Al/S) and alginate/sulfur/hexytiazox (A/H/S) composites were examined on adult famale of two-spotted spider mite Tetranychus urticae Koch (Acari: Tetranychidae). The diameters of sulfur nanoparticles and sodium/sulfur alginate and sodium/sulfur/hexithiazox alginate 300-60 nm were obtained using electron microscopy (SEM). Analysis of FT-IR spectra of sulfur alginate/sulfur (Al/S) and alginate/sulfur/hexytiazox (A/H/S) composites were performed, in the sulfur spectrum, only two peaks 870 and 3435, and in the alginate spectrum 1630, 1457 and 1341 peaks were observed. The highest mortality was obtained 24, 48 and 72 hours after application in the composite (Al/He/S) treatment with LC50 values of 3.48, 2.80 and 2.43 g/l, respectively. Also the lowest mortality was observed 24 hours after using nanosulfur treatment with LC50 value of 20.34 g/l and in 48 and 72 hours in nanosulfur and alginate/sulfur (Al/S) composite treatment with LC50 values of 12.37 and 9.87 g/l, respectively. Hexithiazox treatment with a concentration of 12.7 ml/l after 72 hour aplication showed the highest mortality (70%). Based on the results of this study, composite (Al/He/S) can be recommended in the preparation of commercial acaricide formulations and use in T. urticae integrated management program.

 Bemisia tabaci (Genn.)(Hem: Aleyrodidae)is considered as one significant pest in the agricultural products in Iran. In this research, the effects of ZnO NPs, kaolin, B. bassiana (EUTP105 Isolate) were assessed alone or in combination to Neemarin® compared to thiacloprid insecticide under field conditions on eggs and nymphs of B. tabaci and pupae of its parasitoid Eretmocerus mundus.

This research was handled in the research field of the scientific staff of the Cotton Research Center of East Iran, Kashmar, in a randomized complete block design with three replications in August 2019. The experimental plots were separately 6 m2 and 1.5 m. The recommended concentration of Neemarin® (15 mg L-1 AZA), thiacloprid (0.3 mL L-1), Kaolin (30 g L-1), a concentration of 20 mg L-1 of ZnO NPs, a concentration of 1×1010 conidia mL-1 of B. bassiana, half- concentration of Neemarin® (7.5 mg L-1 AZA) + 10 mg L-1 of ZnO NPs, half- concentration of Neemarin® (7.5 mg L-1 AZA) + 15 g L-1 of Kaolin and half- concentration of Neemarin® (7.5 mg L-1 AZA) + a concentration of 1×105 conidia mL-1 of B. bassiana were prepared which sprayed on upper and lower surfaces of cotton plants using a knapsack sprayer, equivalent to an application volume of 500 l ha-1. The control treatment was sprayed by water. The mortality of B. tabaci eggs and nymphs and pupal stage of E. mundus were calculated using Henderson and Tilton equation . To this purpose, five plants were randomly selected in each plot and three leaves from each one (top, middle, and bottom section of plant canopy) were excised and transferred to a laboratory. Two pieces of 1 cm2 from each leaf were chosen so that the units included into main vein. Total live eggs and nymphs of pest as well pupae of parasitoid in each sample unit were counted using a binocular. Samplings were handled one day before and 3, 7 and 14 days after spraying.

In 3 DAT (days after treatment), the most effective treatments on eggs and nymphs of pest were Kaolin + Neemarin® and thiacloprid, respectively. While, the least effective treatments were B. bassiana. In 7 DAT, Kaolin + Neemarin® and ZnO NPs exerted the highest and lowest mortality, respectively, on the eggs of pest, Neemarin® and B. bassiana exerted the highest and lowest mortality, respectively to the nymph. In 14 DAT, the highest efficacy on eggs and nymphs was observed in Kaolin + Neemarin® and Neemarin®, respectively, while the lowest efficacy both on eggs and nymphs belonged to B. bassiana. The highest and lowest mortality of the pupae of parasitoid in 3 DAT belonged to thiacloprid and B. bassiana, respectively. In 7 DAT, Neemarin® and ZnO exerted the highest and lowest mortality on the parasitoid pupae, respectively.  In 14 DAT, Kaolin exerted the highest mortality on the pupae of parasitoid that was followed by Kaolin + Neemarin®, Neemarin®, and thiacloprid. The maximum yield and benefit/cost ratio were observed in Kaolin + Neemarin®, followed by Kaolin treatments. 

Considering the results, ZnO NPs and Kaolin alone, or in combination to Neemarin® can be the suitable candidates as an alternative in the IPM programs of B. tabaci on the cotton field.