Mohammed Z Khalaf1, Hussain F Alrubeai1 and Ali A Sultan2
1Integrated Pest Control Research Center, Directorate of Agricultural Research, Iraq
2Directorate of Plant Protection, Ministry of Agriculture, Iraq
*Corresponding author: Mohammed Z Khalaf, Integrated Pest Control Research Center, Directorate of Agricultural Research, Iraq
Submission: September 13, 2017; Published: February 23, 2018
ISSN: 2637-7659 Volume1 Issue2
The Sunn pest Eurygaster integriceps is the mostinsecticides with various mode of action were evaluated against Sunn pest Eurygaster integriceps infested wheat on field at middle of Iraq. Experiments were conducted in eleventh wheat fields each measuring 1/2 ha located in the Middle of Iraq (Wasit and Salahudain governorates) at season 2015, contained common varieties of wheat planting in Iraq. The population density of the pest was at its highest level (start of April 2015) of mostly nymphs, adults and eggs. The results indicated that the recommended dose for each insecticides used showed high efficacy (80.1-93.8) in reducing numbers of E. integriceps adults after one week of treatment, reaching 0.2-0.8 insect per 1m2 compared to 3.6 per 1m2 in the control treatment. These results will assist the control program of this pest and in implementing pest management practices to reduce resistance development chances.
Keywords: Efficacy; Insecticides; Sunn pest; Eurygaster spp; Wheat
The Sunn pest Eurygaster integriceps is the most insect of cereals in Iraq and other countries. Field efficacies of ten different kinds of insecticides with various mode of action were evaluated against Sunn pest Eurygaster integriceps infested wheat on field at middle of Iraq. Experiments were conducted in eleventh wheat fields each measuring 1/2 ha located in the Middle of Iraq (Wasit and Salahudain governorates) at season 2015, contained common varieties of wheat planting in Iraq. The population density of the pest was at its highest level (start of April 2015) of mostly nymphs, adults and eggs. The results indicated that the recommended dose for each insecticides used showed high efficacy (80.1-93.8) in reducing numbers of E. integriceps adults after one week of treatment, reaching 0.2-0.8 insect per 1m2 compared to 3.6 per 1m2 in the control treatment. These2015) of mostly nymphs, adults and eggs. The results indicated that the recommended dose for each insecticides used showed high efficacy (80.1-93.8) in reducing numbers of E. integriceps adults after one week of treatment, reaching 0.2-0.8 insect per 1m2 compared to 3.6 per 1m2 in the control treatment. These results will assist the control program of this pest and in implementing pest management practices to reduce resistance development chances.
Keywords: Efficacy; Insecticides; Sunn pest; Eurygaster spp; Wheat
Experiments were conducted in eleventh wheat fields each measuring 1/2 ha located in the Middle of Iraq (Wasit and Salahudain governorates) at season 2015, contained common varieties of wheat planting in Iraq. The population density of the pest was at its highest level (start of April 2015) of mostly nymphs, adults and eggs. Ten insecticides with different mode of action were used to spray the wheat fields with doses as it shown in (Table 1) [10]. Selecting more than one brand of Alphacypermethrin was due to the registration of all these brands by the national committee for pesticides registration and approval and to compare between products of the same active ingredient.
Each treatment contains three replicates (=1000 m2). Numbers of nymphs and adults Eurygaster spp. present per 1m2 were counted carefully directly on the wheat plants of ten m2 Choose randomly per each replicate before and after treatments with one, three and seven days (one week) taken from different parts of plant. Two Sprayer of 100 L EC and 2 L ULV Guarany was used for whole replicates from up to down to insure exposing the pest individuals to the insecticides tested. Complete randomized block design was used in conducting all experiments. Genstat program and LSD (0.05 level) were implied in statistical analysis and determine the significances between insecticides efficacies. Henderson-Tiltons formula [11] was used to calculate corrected insecticides efficacies % on nymphs and adults Eurygaster spp.
Table 1: Tested insecticides used in the experiments of measuring their efficacies on Sunn pest Eurygaster integriceps.
The results showed that recommended doses of the tested insecticides as in (Table 1) gave high efficacies in reduction of field adults and nymphs numbers of E. integriceps on wheat plants. Results in (Table 2) indicate the significant reduction in the average number of nymph and, adults per 1m2 (0.3-1.6) individuals after three days of treatment in comparison with 3.4 individuals in the control of EC treatment. The reduction in number of live adults after one week of treatment reached 0.2-0.8 nymph or adults per 1m2 and 3.6 in the control treatment. Significant differences were found between results of some tested insecticides and that of the controls and for all periods.
Table 2: Field efficacies of some insecticides in controlling sunn pest Eurygaster integriceps in wheat fields. LSD at 0.05= 5.1420, L= low dose, H= high dose.
Insecticides efficacies after one week of treatment ranged between 81.3% for Matrxin plus (Abamactein+Oxymatrixin) as Glutamate-gated chloride channel allosteric modulators and 98.4% for Levo ULV (a.i.Oxymatrin, is one of many quinolizidine alkaloid compounds extracted from the root of Sophora flavescens, a Chinese herb) [12]. Indicated that using insecticides with acetamiprid (SL, Soluble concentrate), chlorpyrifosethyl (EC, Suspension concentrate), lambda-cyhalothrin (CS, capsu Sodium channel modulators le suspension), monocrotophos (SC, Suspension concentrate), thiacloprid (SC) and zeta-cypermethrin (EC) as active ingredient gave high efficacies in controlling E. integriceps adults and reduced subsequent egg laying and the appearance of nymphs in the trial area in Turkey. The low mortality rate compared to the rate (93.8%) obtained during recent investigation could be attributed to the differences of the source and dose rate, in addition to the difficulty of counted adults. The results of treatment of nymphs and adults indicated that spraying with the recommended doses of the tested insecticides (Levo, Golan, Desis, Flash, Telstar, Bestoy and Bestseller) showed high efficacies in nymphs and adults mortality.
The results in (Table 2) showed high effect on nymphs and adults after one week of treatment ranged from 81.3-94.1% for bestoy (Alphacypermethrin as sodium channel modulators) and Golan (Acitamiprid as Nicotinic acetylcholine receptor (nAChR) allosteric modulators) respectively. 86.1%-89.1% for Alphasin (Alphacypermethrin, 10% EC) Sodium channel modulators, Talstar (Bifenthrin 10% EC) Sodium channel modulators and Matrxin (Abamactein+Oxymatrixin) Glutamate-gated chloride channel allosteric.
The result also showed that insecticide flash (35 and 40 ml/100 ml) have the highest efficacy between brands with Alphacypermethrin as active ingredient.
In addition using ULV formula (levo, i.e. oxymatrin) gave the highest efficacy (98.4%) after one week of treatment in controlling sunn pest individuals. Therefore we recommend that application of insecticide must be timed correctly, targeting the most vulnerable life stage of the insect pest and mixing and applying insecticides carefully. In addition a key element of effective resistance management is the use of alternation, rotations, or sequences of different insecticide mode of action classes. It is important to avoid selecting for resistance or cross resistance by repeated use within the crop cycle, or year after year, of the same insecticide or related products in the same mode of action class, but over-use of pesticides in sunn pest its effect on the environment, reduction of the beneficial fauna, costly human health and environment safety [2].
© 2018 Mohammed Z Khalaf, et al. This is an open access article distributed under the terms of the Creative Commons Attribution License , which permits unrestricted use, distribution, and build upon your work non-commercially.