The diamondback moth, Plutella xylostella, is the greatest damaging insect of cabbage plants. Two field experiments were conducted at private farm in El-Kattawia area, Abu-Hammad City, Sharkia Governorate, Egypt to assess the effectiveness of abamectin 1.8 EC against cabbage diamondback moth. Two field experiments were performed at the same farm in different seasons (2019 and 2020).The experiments were conducted in a randomized block design with a plot size of 4 x 5 m with three replications. The concerned treatments were enjoined four times at 14 days intervals beginning from the 30 th day after cultivation. The pneumatic Knapsack sprayer was used to spray fluid (600 liters per hectare). Observations on larval population were made before spraying and on 3, 7, 10, and 14 days after spraying from 10 randomly tagged plants in each plot. Four doses of abamectin @ 9, 11,13, and 15 g a.i.ha -1 were assessed against the Plutella xylostella under study. Besides, Cypermethrin 10 EC @ 70 g a.i./ha , endosulfan 35 EC @ 420 g a.i./ha, spinosad 45 SC @ 75 g a.i./ha, and an untreated blank were also included in the field experiment.The findings concluded that treating with abamectin at 15 g a.i./ ha was the highest mean reduction which meaningfully blocked the population of diamondback moth larvae and recorded a mean reduction of 72.5, 70.7, 75.2, and 78.0 percent from untreated check after first, second, third and fourth sprays, respectively. While the results obtained from abamectin at 11 g a.i./ ha were on par with standard check spinosad at 75 g a.i./ha and excelled over cypermethrin and endosulfan. A similar trend was also observed in the second experiment. The yield of cabbage heads also increased significantly at all the doses tested in the two experiments under field conditions as compared to the control plot. The study demonstrates the potentiality of abamectin 1.8 EC as an eco-friendly bioinsecticide against the diamondback moth (Plutella xylostella). The doses of the studied abamectin @ 15, 13, and 11 g a.i.ha -1 were found to be highly effective to control the infestation of diamondback moth in the cabbage plants under the conditions of a semi-arid zone in Egypt.

Sc ci ie en nt ti if fi ic c S So oc ci ie et ty y o of f A Ag gr ri ic cu ul lt tu ur ra al l S Sc ci ie en nc ce es s

American bollworm, Helicoverpa armigera is the foremost insect that negatively affected cotton crops around the world. A field experiment was conducted at the Sedi-Salem area, Kafr El-Sheikh Governorate,Egypt to assess the bioefficacy of emamectin benzoate 5 SG(EB)on cotton against H. armigera.The tested pesticides were used as a foliar application under field conditions at the2019-2020season.The experiment was designed in plots of 5 m × 5 m size using a randomized block design (RBD) with seven different treatments.A pneumatic knapsack sprayer was used for foliar application of tested pesticides. Three doses of EB @ 7, 11, and 15 g a.i./ha were evaluated against the pest under study. Furthermore, endosulfan 35 EC, Proclaim ® , Spinosad 45 SC, and an untreated blank were also included in the field experiment. The findings concluded that 11 g a.i./ha of EB was the active dose for controlling the larval population of H. armigera.This dose caused a 64.75% reduction of boll damage over an untreated check at the end of observation in the field experiment.The yield ranged from 16.00 to 19.66 q/ha in all treatments.EB at 15 g a.i./ha was a very effective dose which was on par with the final results of 11 g a.i./ha.Entirely EB treatments augmented seed cotton yield under field conditions as compared to the control plot. The study demonstrates the potentiality of EB as an eco-friendly bioinsecticide against the American bollworm.The effective doses of EB @ 11and 15 g a.i./ha should be used in the cotton field to manage the infestation of H. armigera.

Bruchid beetle (Callosobruchus maculatus) is a dangerous pest in stored legumes environment. The present study aimed at assessing the effectiveness of the nitrogen-based modified atmosphere method for combating the bruchid beetle in the managed ecosystem. Besides the control treatment, five laboratory treatments and their replicates were conducted at controlled climatic conditions in 2019 in Egypt. The different oxygen gas concentrations of 2, 5, 8, 11, 14, and 21% O2 were mixed with 98, 95, 92, 89, 86, 79% N2 to form different gas mixtures for the fifth, fourth, third, second, first, and control treatments, respectively, at different exposure times of three, five, and seven days. The adult and egg mortalities were enlarged either by decreasing the concentration of oxygen or by extending the exposure period. The number of newly emerged adults was nearly similar at all the exposure times for all treatments registering no significance of adult emergence variations. The treated stored grains in the fifth treatment achieved 100% egg mortality after seven days of exposure. Seven days of exposure at the rate of 2% O2 were unfavorable conditions for insect growth achieving 100% mortality for the developmental stages of C. maculatus. The lethal concentrations of gases were 2% O2 and 98% N2 at seven days of exposure. The adapted atmospheres of the managed ecosystem with high nitrogen and low oxygen are environmentally friendly insect management techniques for controlling bruchid beetle in stored grains. This research may offer insights for operative stored insect management without any harm to the environment.

Yellow mite, Polyphagotarsonemus latus (Banks) is the greatest destructive pest on pepper plants in Egypt. The efficacy of bifenthrin 25% EC against the yellow mite Polyphagotarsonemus latus (Banks) and its impact on natural enemies (predatory mites) were assessed through three field experiments conducted at Wadi Al-Mollak, East Delta, Egypt for three seasons. The treatments included bifenthrin applied at the rate of 40, 50, 60, 80, 100, 160 and 320g a.i.ha -1 compared with standard check dicofol at 290 g a.i.ha -1 and an untreated check. Obtained percentages of reduction in yellow and predatory mites were 1, 3, 5, 7, and 14 days after spraying. The initial population of mites/leaf before first spraying ranged from 3.83 to 4.91 in all the treatments without any significant difference. The dose of 80 g a.i.ha -1 of bifenthrin had a significant effect on the entire treatments units. The standard check dicofol at 290 g a.i.ha -1 recorded 71.81, 73.63 and 67.76% of reduction in mite population at first, second and third experiment after first spraying, respectively, and 74.76, 85.09 and 76.09% of reduction at first, second and third experiment after second spraying, respectively. The initial population of predatory mites, Amblyseius ovalis ranged from 0.70 to1.11 mites/leaf in the entire treatment. Dicofol at 290 g a.i.ha -1 caused the highest reduction of 49.77, 56.75 and 54.56 % in the first, second and third experiment, respectively. The lowest dose of bifenthrin at 40 g a.i.ha -1 was the least toxic treatment, The toxicity order for different bifenthrin doses against predatory mites and were 320 > 160 > 80 > 100 > 60 > 50 > 40 g a.i.ha-1. Dicofol was highly toxic to A. ovalis compared to bifenthrin treatments. Even after 14 days of spraying nearly 50% reduction was noticed in the case of dicofol. It can be conducted that bifenthrin was found to be relatively safer than dicofol because most likely due to its residues being longer than bifenthrin.