جستجوی مقالات مرتبط با کلیدواژه « chemical control » در نشریات گروه « گیاهپزشکی »

Strains of Pseudomonas syringae pv. syringae (Pss) are pathogenic in various types of plants, sometimes causing economic damage that requires chemical control. In Chaharmahal va Bakhtiary province, this pathogen damages stone fruit trees, wheat, beans, and greenhouse plants like cucumber. This study investigated the resistance of 62 Pss strains from different hosts to copper ions (copper sulfate) in a culture medium. Results showed that 37.1% and 32.3% of the strains were resistant to 100 and 200 µg/ml copper sulfate concentrations, respectively. Five copper-resistant strains from peach, almond, cherry, wheat, and beans and one sensitive strain from cucumber, were selected for further evaluation. The effect of various formulations containing copper compounds on inhibiting the growth of these strains in the culture medium was assessed. All five isolates showed varying resistance to copper compounds (copper oxychloride, copper oxide, copper carboxylate, and Bordeaux mixture). Doubling the concentration of these compounds did not significantly affect bacterial growth. However, adding mancozeb, zinc sulfate, or iron sulfate to each copper compound significantly inhibited bacterial growth on the culture medium. The copper carboxylate formulation combined with mancozeb was the most effective inhibition. The CopA gene, responsible for copper resistance, was detected in the five resistant strains and other Pss strains, confirming the results of the experiments. In conclusion, there is resistance to copper compounds in various Pss strains. For effective chemical control, compounds with a synergistic effect on bactericidal activity should be added to copper compounds. The most influential formulation identified in this study for reducing the population of copperresistant Pss strains and controlling diseases caused by them is a combination of copper carboxylate or copper oxide with mancozeb and urea.

Introduction:

 Wheat (Triticum aestivum) is one of the most important crops in Iran. The area under cultivation of this crop in Fars’s province is 421,000 hectares. Weeds are one of the most significant factors limiting crop production. They primarily decrease grain yield by competing with the crop for light, nutrients, water, and root space.  Weeds can cause a significant reduction in wheat yield, with an average by 23-35%. The most important weed species of wheat in Fars are including Lolium rigidum L., Bromus tectorum L., Mavla neglecta Wallr., Hirschfeldia incana L., Carthamus oxyacanthus M.B., Centaurea solstitialis L., Veronica persica L. The rigid ryegrass (Lolium rigidum) is one of the most troublesome weeds in winter wheat fields of Fars province. Lolium rigidum, has the capacity to produce 45,000 seeds m−2 in infested wheat fields. Its highly competitive nature for nutrients has been reported to cause a significant reduction in wheat yield. The application of herbicides is the most common method of weed control in wheat fields. Herbicides are registered for weed control in winter wheat fields included of Axial®, Topik®, Othello®, Atlantis®, Total®, Bromicide® MA, Geranestar® and Apiros®. There are a limited number of herbicides that is used in wheat. Therefore, it is necessary to register new herbicides in winter wheat. The objectives of this research were to optimize the dosage of FenoMetri in combination with a non-ionic surfactant, Tifis®, and to compare its efficacy with other pre-mixed herbicides (Bromicide® MA, Othello®, and Atlantis®).

 In order to study the efficacy of herbicides for controlling weeds in wheat fields, an experiment was conducted at the Fars Province Agricultural and Natural Resources Research and Education Center, Darab, Iran, during 2021-2022. This experiment was carried out using a randomized complete block design with 14 treatments and 4 replications. The treatments included post emergence application of Bromicide MA® at 1.5 L ha–1 + Topik® at 1 L ha–1, Bromicide MA® at 1.5 L ha–1 +Puma-super® at 1 L ha–1, Granstar® at 20 g ha–1 +Topik® at 1 L ha–1, Atlantis® at 1.5 L ha–1, Othello® at 1.6 L ha–1, Tifis® at 300 g ha–1, FenoMetri  at 0.8, 1 and 1.2 L ha–1 with and without surfactant at 1 L ha–1, Sencor® 800 g ha–1 (400 g ha–1 in the 1- 3 leaf stage + 400 g ha–1 in the tillering stage of wheat and Control (hand weeding). Each plot was divided into two subplots. One subplot was treated with the herbicide applications, while the other subplot was left unsprayed to consider as a weedy check treatment for comparison purposes. Herbicide treatments were applied in tillering stage of wheat (Zadoks’ scale = 25) using a pressure backpack sprayer equipped with an 8002 flat fan nozzle tip, which delivered 350 L ha-1 at 2 bar spray pressure. Traits were recorded including weed density, weed biomass, plant height, grains per spike, number spikes, 1000 grains weigh, grain yield and biological yield. Weed density and dry weight were determined in random 0.50-m2 quadrates per plot. The grain yield and biological yield were recorded for a 3 m2 and 0.50 m2 from each plot, respectively. Weed control efficiency (WCE) representing the degree of reduction in the density or dry biomass of weeds due to herbicide treatment was determined using Equation 1. A and B are the density or dry biomass of weeds in the unsprayed and sprayed subplots, respectively (Somani, 1992). The changes in each trait of yield wheat (Yi), as mentioned above, were determined using Equation 2 Ys and Yu are the amount of each trait in the sprayed and unsprayed subplots (weedy check treatment), respectively. After checking data normality, the data were subjected to analysis of variance using SAS 9.2 software. To compare the means, the Fisher's Least Significant Difference (LSD) test was used at the 5% level of significance.

 Weeds infestations included Lolium rigidum L., Convolvulus arvensis L., Melilotus officinalis (L.) Lam and Carthamus oxyacanthus M.B. The highest and lowest density were observed for L. rigidum (56%) and C. oxyacanthus (5.1%), respectively. While, the highest and lowest weight were observed for L. rigidum (74%) and C. oxyacanthus (4%), respectively. The statistical analysis of the data on the weed density and biomass were revealed that applied herbicides significantly decreased both weed density and biomass. Additionally, the herbicide treatments led to a significant increase in the number of spikes per m², grains per spike, 1000 grains weight, grain yield, and biological yield. The Bromicide MA® had the best treatment for controlling the broad-leaved weed by 80 – 85%, On the other hand, Sencor had the best control for ryegrass (L. rigidum) by 80%. The application of FenoMetri at 1.2 L ha–1 with Surfactant® decreased the biomass of C. arvensis, C. oxyacanthus, M. officinalis, L. rigidum and total weed by 71, 63, 52, 48 and 73% respectively. It also increased grain and biological yields up to 20% and 22% as compared to the weedy check treatment. Additionally, the herbicides of Sencor® and Othello® showed the highest- grain yield after hand weeding, respectively.

 The application of FenoMetri at 1.2 L ha–1 with surfactant effectively controlled the density of weed species by 45–71% and the dry biomass of weed species by 48–72%. It also increased grain and biological yields by up to 20% and 22%, respectively, compared to the weedy check treatment. However, the efficacy of FenoMetri herbicide in controlling weeds was lower compared to commonly used herbicides such as Othello®, Bromicide MA® + Topik®, and Bromicide MA® + Puma super®. Therefore, it is recommended to evaluate the FenoMetri herbicide with higher application rates.
 

Scab disease of apple caused by Venturia inaequalis is one of the most important diseases of apple in the world and Iran. Especially in areas with wet and cold weather its damage reach more than 70%. Apple scab results in symptoms on most upper plant parts, notably leaves and fruit.  Petioles, flowers, sepals, pedicels, young shoots, and bud scales can also become infected. Apple scab infections are initiated in early spring on emerging and young leaves. The Mills table relates leaf wetness duration and temperature to determine the likelihood that conidial infection will occur. For example, at an average temperature of 18°C (65°F), light infection will result if leaves remain wet for 9 h. Lesions can produce conidia after 9 days if the temperature averages 18°C (65°F), but not until 17 days if the temperatures are lower, averaging only 8°C (49°F).

The experiment was conducted in apple orchards located in Yasuj, Bojnourd and Karaj which had a history of apple scab. The experimental design was a randomized complete block design (RCBD) with 8 treatments and 4 replications. The control treatments included plots without any spraying and plots sprayed with water. The remaining treatments involved the application of specific treatments at three different stages. The first spraying was done at swelling of leaf buds time, the second spraying after fall leaves, and the third spraying 14 days after the second spray. 30 days after observing the first symptoms of the disease in the controls, samples were taken from the leaves and fruits to evaluate the percentage of the disease density and severity of the disease. The data obtained for disease incidence and severity were analyzed using statistical software, such as SAS, and the means of these traits were compared using Duncan's multiple range test at a significance level of one percent. This test helps determine significant differences between the treatment means.

Results and Discution:

The analysis of variance conducted on the data obtained from the evaluation of treated trees revealed a statistically significant effect of the treatments on reducing the percentage of disease severity and disease incidence. Result showed that, there are significant differences between treatments and controls in all three provinces (P = 5%). Mean comparisons of the treatments showed that, all fungicides caused a significant decrease in the severity and incidence of disease infection percent compared to controls. The results of three provinces showed that new fungicide Luna Sensation 500® SC 0.4 and 0.6 ml L-1 and Flint® 50% WG 0.2 ml L-1 during three times spraying is very effective on controlling of apple scab. In Kohghiloyeh and Boyerahmad, 0.4 and 0.6 ml L-1 of Luna Sensation had the best efficiency compared to other treatments. The severity of disease was lower than control about 96 percent in leaves and 98 percent in fruits. Also, incidence of disease in fruit and leaf of these treatments were lower than the other treatments. In North Khorasan province Flint 0.2 ml L-1 and Luna Sensation 0.4 compared to other treatments was more effective in controlling the disease severity and approximately 75 percent compared to controls reduced disease severity on fruits. Also on leaves Luna Sensation 0.4 were effective approximately 80 percent. In terms of disease control on fruit, there were no significant differences between all fungicide treatments except benomyl. Disease incidence on the leaves treated with all three concentrations of Luna Sensation and 0.2 ml L-1 Flint was lower than other treatments. In Alborze province, Luna Sensation 0.4 and 0.6 ml L-1 and Flint 0.2 ml L-1 had the best efficacy and nearly 100 percent decrease severity and incidence of disease in leaves in compared with controls. The results of three provinces showed that new fungicide Luna Sensation 500® SC 0.4 and 0.6 ml L-1 and Flint® 50% WG 0.2 ml L-1 during three times spraying is very effective on controlling of apple scab. Also, the results showed that Luna Sensation fungicide can control apple scab disease on Golden Delicious and Red Delicious and The type of cultivar has no effect on the efficacy of the fungicide. Results show that Luna Sensation 500® SC 0.4 is an effective fungicide to control apple scab and can be used in apple orchards as a part of integrated pest management program. The management of apple scab disease in the world usually requires multiple sprayings, from the greening stage of the branches to harvest. Since V. inaequalis has a high risk of developing resistance to fungicides, the alternating use of effective fungicides from different groups and with different mechanisms of action or the use of fungicides with multiple mechanisms of action in disease management programs are necessary to prevent resistance. The new fungicide Lunasenish® SC 500, which is composed of 21.4% trifloxystrobin, 21.4% flupiram and 57.2% related substances, is a systemic fungicide with a wide range of effects.

Tomato early blight caused by Alternaria alternata, A. tenuissima and A. solani, occurs in a wide range of environmental conditions. Effectiveness of fluxapyroxad+difenoconazole (Dagonis® SC12.5%), tetraconazole+azoxystrobin (Affiance® SC17%) and mandipropamid+difenoconazole (Carial Star® SC 50%) fungicides were evaluated in the control of tomato early blight disease in comparison with boscalid+pyraclostrobin (Signum® WG33.4%) fungicide. Dagonis® at the rates of 800, 1000 and 1200 ml/ha, Affiance® 450, 600 and 750 ml/ha, Carial Star® 400, 550 and 700 ml/ha and Signum® 500 gr/ha and the control group (no fungicide application). The experiments were carried out under the field condition in Fars and Hormozgan provinces, and under greenhouse condition in Alborz province. The disease severity index and area under the disease progress curve were calculated. The results showed that Affiance® at the rates of 600 and 750 ml/ha with 48-82% efficacy, Dagonis® at the rate of 1200 ml/ha with 50-70% efficacy and Signum® at the rate of 500 gr/ha with the efficacy of 48-75% were effective in controlling tomato early blight disease. Although Carial Star® fungicide with the amount of 700 ml/ha was less effective (45-55%) as compared to aforementioned fungicides, but its average efficiency can be justified. Therefore, Affiance®, Dagonis® and Signum® fungicides, at the rates of 600, 1200 ml/ha and 500 gr/ha, respectively, and Carial Star® fungicide (in the early stages of the disease) at the rate of 700 ml/ha are recommended to control tomato early blight disease.

Leopard moth, Zeuzera pyrina L. is an important woodborer in orchards especially on walnut trees. Its damage has been remarkably increased in Urmia region in recent years. In this research, the amount of pest damage was compared on different orchards such as apple, walnut and peach. The best control method of pest was investigated by using of two insecticides, pheromone and light traps in field conditions. The highest pest damage was observed on walnut trees in Balo village and the least damage was recorded in Gajin and Haji-Abad villages. Old walnut trees (25-30 years old) suffered more damages than younger trees. In 2020, peak of adult leopard moth emergence was recorded in May 29 by using pheromone trap via mass trapping. Two weeks after flight peak, control methods including the use of Hexaflumuron and Imidacloprid insecticides along with pheromone and light traps were assessed. Based on the obtained results, Hexaflumuron along with the pheromone trap exhibited the best efficacy considering the reduced pest damage in 2021. Thus, this method can be used effectively in integrated management program of leopard moth.

Wheat is a crucial crop that plays a significant role in ensuring food security in Iran. Weeds have been one of the major limiting factors for wheat production in Iran and globall. If they are not adequately controlled. Weeds can cause significant damage to wheat crops. Weed damage in wheat fields has been reported to range from 20% to 30% in Iran. The herbicide application is the most important method for weed control of wheat until now. Axial-one@ herbicide, with common names of pinoxaden+ florasulam, has been suggested for weed control of Lollium rigidum, Echinochloa colonum, Alopecurus myosuroides, Phalaris brachystachys, Avena ludoviciana, Stellaria media, Trifolium alexandrinum, Polygonum aviculare, Sinapis arvensis, Ambrosia artemisiifolia, Amaranthus retroflexus, Cirsium arvense. This herbicide has been registered by Syngenta for use in wheat and barley. Pinoxaden (Axial@) belongs to phenylpyrazolines family and inhibitors of the Acetyl-CoA carboxylase (ACC). It has been recorded in the control of narrow-leaved weeds in wheat and barley. Florasulam herbicide belongs to the triazolopyrimidine sulfonamide family and inhibits acetolactate synthase (ALS). Florasolam is the selective herbicide that has been recommended for controlling broadleaf weeds in cereals such as wheat, barley, oats, rye (Secale cereale L.) and triticale (Triticale hexaploid Lart). Also, the Cassic herbicide, which is also known as diflufenican+iodosulfuron-methyl-sodium+florasulam+cloquintocet-mexyl, is a dual-purpose herbicide that has been registered by Syngenta for controlling both broadleaf and narrow-leaved weeds in wheat and barley, oats, rye, and triticale crops. This experiment was conducted to investigate the effectiveness of the herbicides of Cassic and Axial-one in the controlling weeds in wheat fields, determination of the most appropriate dose, comparing their effectiveness with other herbicides commonly used in wheat fields, and evaluating the response of wheat plants to the herbicides.

 An experiment was carried out in weed control in the wheat fields of Karaj, Fars (Darab), Golestan (Gonbad), and Shahrud using a randomized complete block design with 13 treatments and 4 replications during 2020-2021. Experimental treatments included the application of Bromycid AM (bromoxynil + MCPA, 40% EC) + Axial (Pinoxaden, 5% EC) at 1.5 + 1.2 l/ha, Othello (diflufenican+ mesosulfuron methyl+ iodosulfuron methyl sodium, 6%OD) at 1.6 l /ha, Axial One (Pinoxaden+ Flurasulam, 5% EC) at 1.1, 1.3, 1.5, 1.7 l/ha, Cassic (diflufenican+ iodosulfuron-methyl-sodium+ florasulam+ cloquintocet mexyl, 47% WG) at 170, 200 and 230 g/ha with and without cytogit, and control (weed free). Herbicide treatments were applied during the tillering stage (Zadok’s Stage 25(. The plot had dimensions of 8 x 2 m with a plant density of 400 plants m-2. Each plot consisted of 8 planting lines with a row spacing of 15 cm. The distance between the plots was one meter, and there was a two-meter gap between replications. To increase the accuracy of the experiment, each test plot was divided into two equal sections, with the upper half serving as the control without spraying and the lower half being sprayed. The spraying was done using a fixed-pressure back sprayer equipped with a fan spray nozzle (8002) at a pressure of 2 bar and spray volume of 300 L ha-1. Traits such as weed density, weed biomass, and grain yield were recorded. Weed numbers and dry weights were determined by randomly selecting 0.50-m2 quadrats per plot, while grain yield was recorded for 3 m2 in each plot. The data were checked for normality and analyzed using SAS 9.3 software through analysis of variance. The means were separated using the Duncan test at the 5% level of significance. 

 The results of experiment indicated that the herbicide treatments led to a significant decrease in the density and dry weight of weeds, as well as a significant increase in grain yield. The Axial One@ at rate 1.7 L ha-1 was found to be more effective in controlling Avena ludoviciana, reducing its density by 95%, compared to On the other hand, Cassic herbicide at a rate of 230 g per hectare was more effective in controlling Lolium rigidum, reducing its density by 95%, compared to Axial One@ herbicide. Both herbicides, however, led to a significant reduction in the dry weight of Descurania sophia, Polygonum avicular, Sonchus oleracea, Veronica persica and Sinapis arvensis from 85 to 95%. No visual injury symptoms were observed on wheat after the application of these herbicides. Grain yield increased with the application of Axial One (at rate of 1.5 to 1.7 L ha-1) by 5 to 24%, and Cassic (at rates of 200-230 g ha-1 + cytogit) by 8 to 28%. These findings were consistent with the results of previous studies (Minbashi et al., 2020). The application of Oxial herbicide increased grain weight of wheat (Azhar et al., 2013).

 Based on the results of these experiments, it can be concluded that Axial One@ and Cassic@ herbicides showed the best control on A. ludoviciana and L. rigidum respectively, and also led to a significant increase in grain yield compared to half of the control plot. Therefore, the Axial One@ (1.7 L ha-1) and Cassic@ (200-230 g ha-1 + cytogit) can be considered as good to excellent options for weed control in wheat fields. It is recommended to use these herbicides for weed control in wheat fields.

In order to evaluate the effectiveness of chemical control in the management of Fusarium diseases of corn, the present study was conducted using eight fungicides including Carboxin-Tiram (Vitavax -Tiram, 75% WP) as reference fungicide, Difenoconazole (Dividend DS 3%), Tebuconazole (Raxil DS 2%), Azoxy-strobin + Difenoconazole (Ortiva Top SC 32.5%), Trifloxystrobin (Flint WG50%), Protioconazole + Tebuconazole (Lamardur FS40%), Fludioxonyl + Metallaxyl M (Maxim XL FS) and Azoxystrobin + Metalaxyl M (Uniform SE 44.6 %) in three phases: laboratory, growth chamber and field. According to the results, all fungicides used in this research showed significant performance and effectiveness in control of Fusarium corn diseases compared to check in most of the traits evaluated, and application of them recommended as seed treatment before planting. In laboratory, Maxim and Raxil were considered as the most effective fungicides comparing the reference fungicide, Carboxin-Tiram. The most effective fungicides in growth chamber were Maxim, Lamardor, Ortivatop and Dividend, each of which showed higher efficiency than the reference fungicide in one or more traits. In field investigations in Golestan province, Maxim, Uniform and Ortivatop (with 93.9, 91.4 and 88.2% of check, respectively), in Ardabil province Maxim and Lamardor (with 51.5 and 41.7 % of check, respectively) and in Mazandaran province, Lamardor and Raxil (with 54.4% and 43.5% of check, respectively) were more effective compared with the infected control and showed better efficiency than the reference fungicide in most traits.

The effectiveness of Azotobacter-enriched vermicompost tea and non-chemical treatments were investigated on the control of tomato leafminer, Tuta absoluta. The experiment was performed in greenhouse with five treatments (vermicompost tea, azotobacter-enriched vermicompost tea, takumi pesticide, Azotobacter and control) in four replications under a completely randomized design. Three days after spraying, the numbers of larval tunnels on leaf and thirty days later, the numbers of adult moths of T. absoluta were counted. The results revealed that tomatoes treated with Azotobacter enriched vermicompost tea and Takumi had the lowest number of adult moths (9.35 and 13.75 per plant respectively). As well as, azotobacter treatment was able to reduce the adults moth by up to 50% compared to the control. The results of the number of larval tunnels showed that the mean number of larval tunnels/plant for Azotobacter enriched vermicompost tea was 19.50, which compared to other treatments, had the best effect in reducing the damage of tomato leaf miner. Vermicompost tea and Azotobacter as biological fertilizers, besides being able to increase the yield of tomatoes, have an effective role in reducing the population and damage of the tomato leaf miner pest, and they can be used in sustainable agriculture as an alternative with pesticides.

Scab disease caused by Venturia inaequalis is the most important diseases of apple in the world which causes serious damage, especially in areas with wet and moderate weather. In order to investigate the effect of fungicides on the time progression curve of apple scab disease in North Khorasan province, the experiment was conducted in the form of Randomized Complete Block Design with eight treatments and eight replications in Bojnord city. With the appearance of disease symptoms, samples were taken in a regular schedule every week until the disease progression was reduced in the control.  Disease Incidence and severity percentage of the disease in each tree were determined and statically analyzed. Using linear regression, disease progression curves were fitted with six growth models as conventional models including linear, exponential, monomolecular, logistic, log-logistic and Gompertz linearized. The results showed that the progression curves changes from the Gompertz model in the control samples by using of fungicides according to the efficiency of each treatment to the log-logistic model and finally to the monomolecular model.

The oriental spider mite, Eutetranychus orientalis Klein (Acari: Tetranychidae), is an important pest of Indian siris and some other trees in Ahvaz’s green landscape. By feeding on the Indian siris leaves, this pest causes leaf fall, reducing the aesthetic and green surface and its resistance to other potential pests and diseases. One of the important strategies to control the pest is application of acaricides. The choosing the efficient and safer acaricides plays critical role considering the daily contact of a large number of citizens with the urban green space. In this research, the short-term and long-term effectiveness of four pesticides abamectin, Palizin®, etoxazole, and Nimazal® which are all low-risk pesticides for humans and mammals, at concentrations 0.5, 2, 0.5, and 1 (L/1000 L), were evaluated to control the pest mite population in a field study, respectively. For this purpose, the population of nymphs and adults of this mite was recorded on the treated trees 1 day before, 2, 7, 14, and 21 days after treatment and statistically compared with the control treatment where the trees were treated only with water. This study showed that abamectin and etoxazole had very favorable short-term and long-term effects on E. orientalis population. Although Palizin® led to the control of the pest in the short term, it did not have a favorable long-term protective effect, and as a result, the treatment of trees has to be repeated in order to properly control the pest. Nimazal® also showed its effect with two to three weeks lag time and this effect was relatively lower than abamectin and etoxazole.

Due to the long-term use of some chemical insecticides to control rice striped stem borer, Chilo suppressalis in rice fields in the north of Iran and in order to prevent the development of stem borer resistance to them, it is necessary to use new insecticides such as thiocyclam hydrogen oxalate granules 4% (Vibrant®) to control this pest. Experimental treatments in this research include, 1- (VibrantR) granule insecticide 4% at the rate of 10 kg/ha. 2- (VibrantR) granule insecticide at the rate of 12.5 kg/ha. 3- (VibrantR) granule insecticide 4% at the rate of 15 Kg/ha. 4- Diazinon granule insecticide 10% at the rate of 15 kg/ha. 5- Fipronil granule insecticide 0.2% at the rate of 20 kg/ha. 6- Control (only watering). The present study was conducted in the form of randomized complete block design with 3 replications. The following characteristics including: the percentage of dead hearts in the first generation, the percentage of white heads in the second generation, the percentage of insecticide efficiency, the population of larvae and the yield of rice were evaluated. The results of this research showed that among the tested insecticides, (Vibrant®) insecticide in amounts of 12.5 and 15 kg per hectare has significant advantage in controlling the rice stem bore for the first and second generations of the pest, respectively. Also, the results of this study showed that the least contamination of dead hearts (5.22%), white heads (2.33%), the highest larval mortality (86.01%) and the highest yield (4020.83 kg/ha.) was observed in the treatment Vibrant 4% in the amount of 15 kg/ha. Therefore, the findings of the present study indicate that the new thiocyclam hydrogen oxalate insecticide has a good potential in controlling rice striped stem borer and can be used for integrated management of stem borer in paddy field ecosystems.

Bell pepper with the scientific name Capsicum annuum L. belongs to the Solanaceae family. Among the major pepper diseases, root rot caused by the fungus Rhizoctonia solani has the economic importance. The common method to control this disease is to use the chemical fungicides. In order to control Rhizoctonia root rot disease of bell pepper, a number of commercial biological agents based on Trichoderma harzianum, Glomus sp. mycorrhizal fungus, Bacillus sp. and Pseudomonas sp. bacteria and three chemical fungicides Tebuconazole, Copper oxychloride and Mancozeb were investigated in greenhouse conditions. The analysis of variance showed that the treatments had significant difference (P≤ 0.01) in all the examined traits. The mean comparisons of the treatments were evaluated based on disease inhibition traits including the length of the necrotic tissue with the largest wound and the disease index and plant growth promotion traits, including plant fresh weight, plant height, root dry weight and shoot dry weight. The treatments of negative control (no pathogen) and fungicide tebuconazole had the greatest effect on most of the traits, and the treatments of Potabarvar and Mycoroot and positive control (with pathogen) had the least effect. Among the biological control treatments, based on the lowest disease index and the lowest wound length, the combination of biological agents, Parsbacil, Probio96, Alkagreen, Trichoran-P and Tricho were ranked respectively. In the study of agricultural traits, biological treatments, combination of biological agents, Parsbacil and Probio-96 showed the highest values. In the management of this disease, apart from the chemical control method (Tebuconazole), the best option with a relatively similar statistical level was Parsbacill combination (SC) containing Bacillus velezensis strain M11-RTS, and Probio-96 containing Bacillus subtilis bacteria (P≤ 0.01).

Two spotted spider mite Tetranychus urticae Koch is one of the most important pests of agricultural products that damages many plants, including cucumber in greenhouses. A new acaricide Oberon Speed®) abamectin, EC 8.1% + spiromesifen, SC 24% (0.4 ml/l and 0.5ml/l was compared to Kanemite® (acequinocyl, SC 15%) 1.25 ml/l, Danisaraba® (Cyflumetofen, SC 20%), 1 ml/l and control treatment (Water spraying) for efficacy against spider mite under greenhouses condition in Kerman (Jiroft city) and Isfahan (Isfahan city) provinces. Sampling of each treatment was done at one day before spraying then 3, 7 and 14 days after spraying respectively. The percentage of efficiency was calculated using Henderson-Tilton formula and statistical analysis was conducted using SAS software with randomized complete block design. In two provinces, the mean mortality of treatments was significant. In Jiroft, the mean mite mortality of Oberon Speed® 0.5 ml/l at 3 and 7 was 89.57% and 91.57% and the efficacy declined on 14th day (63.90%). During the test, Kanemite® and Oberon Speed® 0.4 ml/l caused mortality in the range of 76.30-89.04% and 56.89-75.63%. In Isfahan, the efficacy of Oberon Speed® 0.4 ml/l and 0.5 ml/l was 74.08-63.99% and 91.9.-79.61% respectively and Danisaraba® effected 71.98-87.38%. Result showed that mite mortality of Oberon Speed® 0.5 ml/l recorded more than 74.73% in both provinces and it can be recommended for control of spider mite in greenhouse cucumbers; there were no residues of Oberon Speed® 0.4 ml/l and 0.5 ml/l, after 7 days spraying.

Downy mildew disease caused by Plasmopara viticola (Berk. & Curt.) Berl. & Toni is one of the most important diseases of vine. Especially in wet areas, it causes qualitative and quantitative damage to the crop. Although all green parts of the grapevine are susceptible, the first symptoms of downy mildew of grapes are usually seen on the leaves as soon as 5 to 7 days after infection. Foliar symptoms appear as yellow circular spots with an oily appearance (oilspots). Young oilspots on young leaves are surrounded by a brownish-yellow halo. This halo fades as the oilspot matures. The spots are yellow in white grape varieties and red in some red grape varieties (e.g., Ruby Red). Under favorable weather conditions, large numbers of oilspots may develop and coalesce to cover most of the leaf surface. After suitably warm, humid nights, a white downy fungal growth (sporangia) will appear on the underside of the leaves and other infected plant parts. The disease gets its name "downy mildew" from the presence of this downy growth. In late summer and early fall, the diseased leaves take on a tapestry-like appearance when the growth of the pathogen is restricted by the veinlets. Confirmation of active downy mildew is made by the "bag test." To do this test, seal suspect diseased leaves and/or fruit bunches in a moistened (not wet) plastic bag and incubate in a warm (13-28ºC), dark place overnight. Look for fresh, white downy sporulation beneath suspect oilspots or on shoots or fruit bunches. Note that mature berries, although they may be symptomatic and harbor the pathogen, may not support sporulation even when provided with ideal conditions. Infected parts of young fruit bunches turn brown, wither, and die rapidly. If infections occur on the young bunch stalk, the entire inflorescence may die. Developing young berries will either die or, if between 3 and 5 mm in diameter, become discolored. Berries become resistant to infection within 2-3 week after bloom, although all parts of the rachis may remain susceptible 2 months after bloom. The pathogen survives the winter period as oospores embedded in dead leaves and other host tissue on the vineyard floor. Oospores may be released from the decaying plant material on the soil surface. Oospores typically produce sporangia. These sporangia, in turn, produce zoospores. Sporangia and zoospores are splashed by rain or carried by wind to the lower leaves and tissues of the grapevines. The conditions necessary for oospore germination are wet soils with temperatures above 10ºC. Sporangia for secondary infections are produced on sporangiophores that emerge through stomata of infected leaves and other grapevine tissues. Sexual reproduction occurs towards the end of the season. The resulting oospores are thick-walled and serve as survival spores.

 The experiment was conducted in grape orchards located in Hamadan, Bojnourd, and Faruj, which had a history of Downey mildew. Different cultivars of grapes were selected for the experiment. The experimental design used was a randomized complete block design (RCBD) with 8 treatments and 4 replications.The control treatments included plots without any spraying and plots sprayed with water. The remaining treatments involved the application of specific treatments at three different stages. The first spraying was done before flowering, the second spraying after fall petals, and the third spraying 10 days after the second spray. Ten days after the final spraying, samples were collected from the grape leaves, and the percentage of disease incidence and disease severity were calculated. The data obtained for disease incidence and severity were analyzed using statistical software, such as SAS, and the means of these traits were compared using Duncan's multiple range test at a significance level of one percent. This test helps determine significant differences between the treatment means.

 The analysis of variance conducted on the data obtained from the evaluation of treated grape leaves revealed a statistically significant effect of the treatments on reducing the percentage of disease severity and disease incidence. Among the treatments, Profiler® at concentrations of 3 ml L-1, 2.5 ml L-1, and 1 ml L-1, Mishocap® at 3 ml L-1, and Captan at 3 ml L-1 demonstrated high efficiency in controlling grape Downey mildew disease. The new fungicide Profiler® at a concentration of 3 ml L-1 exhibited an efficacy of 94% in Hamadan, 67% in Bojnourd, and 47% in Faruj. Profiler® at a concentration of 2.5 ml L-1 had slightly lower efficacy, but the difference was not statistically significant compared to Profiler® at 3 ml L-1. Interestingly, the control treatments, including water spraying and no spraying, did not show a significant difference in disease control compared to the treated plots. These results indicate that Profiler® at appropriate concentrations and Mishocap® and Captan at their recommended concentrations can be effective options for controlling grape Downey mildew disease.

 Because both Profiler® 3 and 2.5 ml L-1concentrations are effective in controlling the disease, therefore in order to protect the health of the consumer and the environment as well as reduction in costs, the preferred dose is 2.5 ml L-1.

Introduction Wheat (Triticum aestivum) is one of the most important crops in Fars province and Iran. The area under cultivation of this crop is 337,000 hectares in Fars’s province. The weeds are one of the most famous factors limiting in the production of wheat in Iran and the world. Weeds can decrease grain yield of wheat by competing for resources such as water, light and nutrients and production of allelopathic compounds. If weeds are not controlled at this crop, cause great damage to the wheat. The amount of weed damage in wheat fields of Iran has been reported to be about 20 to 25%. The most important weeds of wheat in Fars are including Mavla neglecta Wallr., Centaurea solstitialis L., Veronica persica L., Carthamus oxyacanthus M.B., Capsella bursa-pastoris, L., Descurainia Sophia (L.) Webb&Berth, Hirschfeldia incana L., Lolium rigidum L., Avena fatua L., Bromus tectorum L. Application of herbicides is the most prevalent method of weed control in wheat fields. There are 26 herbicides registered for weed control in wheat in Iran, which are mainly used post-emergence. Herbicides are recommended for weed control in wheat included of Total, Othello, Atlantis, Geranestar, Bromicid MA, Apiros, Tapik and Axial. Therefore, it is necessary to register new herbicides with different site of action in this crop. This experiment was conducted to investigate the new herbicide efficacy of clodinafop propargil+ metribuzin in control of wheat fields, determination of the most appropriate dose, comparison of the effectiveness of new herbicide with the herbicides was recorded in wheat and the reaction of wheat to the herbicideMaterials and Methods In order to study the effect of herbicides to control weeds of wheat fields, an experiment was conducted during 2020- 2021 at Fars Agricultural and Natural Resources Research and Education Center, Darab, Iran. Plots were located on a clay loam soil with pH 7.9. This experiment was carried out in randomized complete block design with 13 treatments and 4 replications. The treatments included post emergence application of Total (methsulfuron+ sulfosulfuron, 80% WG) at dose rate of 40 g ha-1, Othello (mesosulfuron+iodosulfuron+ diflufenican, 6% OD) at dose rate of 1.6 L ha-1, Tapik (clodinafop propargil, 8% EC) + Geranestar (tribenuron, 75% DF) at dose rates of 0.8 L ha-1+ 20 g ha-1, Tapik (clodinafop propargil) + Bromicid MA (bromoxynil+ MCPA, 40% EC) at dose rates of 1 L ha-1+ 1.5 L ha-1, ACM– 9 (clodinafop propargil + metribuzin, 29% WP) at dose rates of 500, 600, 700 g ha-1, Shagun 21-11 (clodinafop propargil+ metribuzin, 54% WG) at dose rates of 200, 300, 400, 500, 600 g ha-1 and weeding control. The herbicides were applied using a Matabi sprayer equipped with an 8002 flat fan nozzle tip delivering 350 L ha-1 at 2 bar spray pressure. Weed numbers and dry weights were determined in random 0.50-m2 quadrates per plot. The grain yield and biological yield were recorded for a 2 m2 and 0.50 m2 from each plot, respectively. Parameters were recorded including and control percentage of density, weed biomass, plant height, grains per spike, number spikes, 1000 grains weigh, grain yield and biological yield. Statistical analyses of data were done with SAS var 9 software and comparison of mean was tested using the LSD test at 5% level.Results and DiscussionThe weed infestations in the study consisted of Hirschfeldia incana L., Centaurea pallescens L., Veronica persica L., Malva neglecta L., Lolium rigidum L., and Convolvulus arvensis L. Among these weeds, Centaurea pallescens had the highest relative weight at 24%, while Convolvulus arvensis had the lowest relative weight at 8%. In terms of relative density, Veronica persica had the highest value at 44%, while Convolvulus arvensis had the lowest at 7%. Statistical analysis of the data revealed that the application of herbicides significantly reduced weed density and biomass. It also led to increased plant height, number of spikes per m2, grains per spike, 1000 grains weight, grain yield, and biological yield. Visual observations confirmed the effective control of these weeds using the ACM herbicide at a dose rate of 700 g ha-1. The best herbicide treatment for weed control was Tapik+ Bromicid MA, followed by ACM herbicide at a dose rate of 700 g ha-1. The ACM herbicide at a dose rate of 700 g ha-1 resulted in a significant reduction in biomass for Malva neglecta (87%), Lolium rigidum (76%), Hirschfeldia incana (81%), Centaurea pallescens (90%), Veronica persica (86%), and total weed (80%) compared to the weed control. Furthermore, when the ACM herbicide was applied at a dose rate of 700 g ha-1, the grain yield and biological yield were 5.65 and 14.51 tons ha-1, respectively. This treatment also led to a 26% increase in grain yield and a 25% increase in biological yield compared to the control.Conclusion Results showed that applications of powder formulation of clodinafop+ metribuzin herbicide at dose rate of 700 g ha-1 had acceptable weed control efficacy and increased wheat yield. Therefore, the application of clodinafop+ metribuzin (WP) herbicide at dose rate of 700 g ha-1 is suggested for wheat fields.

Aphis gossypii Glover is a polyphagous pest that infects a wide range of host plants in temperate, tropical and subtropical regions. Therefore, it has a great ability to maintain its population in different environmental conditions. Quantitative and qualitative damages of this pest are through feeding on plant sap, transmission of viral diseases, reduction of photosynthesis and secretion of honeydew. Various factors such as excessive use of chemical insecticides, the destruction of natural enemies and the emergence of resistant pest populations have increased the population of aphids and turned it into a damaging pest. However, the most common method of controlling aphids, despite its negative effects, is usage of chemical insecticides. The high potential of this pest in resistance to chemical compounds requires investigating and using of newer insecticides with different modes of action. Insect reproductive parameters as an ecological and indicator tools, can indicate the behavior and physiology of different types of pests after pesticides using. Studies have also been conducted on the effect of sub lethal concentrations of insecticides on behavior, biological characteristics and growth of insect population, which provides a more realistic estimate of the effect of insecticides on pests and natural enemies. Therefore, in this study, the lethal and sub lethal effects of the new combined insecticide Emamectin benzoate 4.8% + Acetamiprid 6.4% which has contact and oral function, was evaluated on the aphids biological and population growth parameters in greenhouse conditions.

The colony of cotton aphid used in the experiment was obtained from pinto beans fields in Urmia, West Azerbaijan (Iran), during September 2021. The aphid population was reared on pinto beans var. Khomein in plastic pots (12 × 6 cm) under controlled greenhouse conditions (21 ± 1°C, 50% ± 10% RH, and a photoperiod of 16: 8 [L: D] h). The LC50 concentration of Emamectin benzoate + Acetamiprid for cotton aphid adults was 23.84 ppm 24 hours after treatment. The values of LC10, LC20 and LC30 were estimated at 1.76, 4.31 and 8.22 ppm, respectively. The insecticide spraying method on leaves containing aphids was used in bioassay and life table studies against adults of aphid insects. The age stage, two-sex life table method was used to analyze the collected data. We used the bootstrap technique with 100,000 iterations to estimate the variance and standard errors of the biological and population parameters and used Sigma Plot software to draw graphs. The growth of the pest population in a period of 60 days was done with Timing-MsChart software.

According to the results, the adult lifespan/longevity was significantly different from the control by LC20 and LC30 concentrations. The shortest lifespan of adult aphid in LC30 treatment was recorded as 5.90 days. Fertility and the duration of Nymphal period were significantly reduced in sub lethal concentrations of the insecticide compared to the control. The highest value of pre adult period in LC30 concentration was recorded 8.88 days and the lowest value in control treatment was 5.06 days. All biological table parameters of cotton aphid treated with sub-lethal concentrations were significantly affected by the insecticide compared to the control. The highest value of intrinsic rate of increase (r) was 0.39 per day in control. The net reproductive rate (R0) decreased from 28.37 nymphs per female/generation in control to 6.90 in LC30 concentration. The lowest value of finite rate of increase (λ) was observed in LC30 concentration, which was 1.18 per day. The gross reproductive rate (GRR) in sub lethal concentrations was significantly lower than the control. The highest and lowest values of mean generation time (T) were estimated in LC30 (11.28 days) and control (9.11 days), respectively.

Based on the findings of the present study, considering the necessity of using chemical insecticides for aphid management, and the significant effect of this pesticide on the aphid Emamectin benzoate + Acetamiprid insecticide can be used to control and reduce population of cotton aphids and it can be a suitable alternative to old insecticides. In order to confirm the greenhouse results, it is necessary to conduct similar experiments in field conditions, and conduct laboratory and field studies on the effects of this compound on the natural enemies of A. gossypii especially bees and coccinellids.

Grape leafhopper, Arboridia kermanshah is one of the important pests of vineyards in Sistan region, which weakens the trees and reduces the quality and quantity of grape production by laying eggs in the leaf tissue, and feeding on leaves and transmission of viral pathogens. During the recent years, grape leafhopper populations have increased sharply in vineyards in Sistan region. This study was conducted in 2019-2020, to evaluate the effect of some insecticides on grape leafhopper by spraying on the grape foliage. The studied insecticides were Thiamethoxam (Actara WG 25%), Thiaclopride(Biscaya OD 24%), Spirotetramat(Movento SC 10%), Imidacloprid(Confidor SC 35%), Fipronil(SC 5%), Chlorfluazuron(Atabron EC 50%) and Control. The insecticide efficacy, seven days after spraying in the first and second years were 100 and 90.10% for Thiamethoxam, 99.33 and 91.06% for Thiaclopride, 99.74 and 71.97% for Spirotetramat 0.75ml/lit, 99.79 and 83.14% for Spirotetramat 1ml/lit, 95.63 and 97.56% for Imidacloprid, 84.22 and 71.97% for Fipronil, 84.13 and 66.84% for Chlorfluazuron respectively. Fipronil and Chlorfluazuron had less effective on this pest compared to other treatments. In general, Thiamethoxam, Thiaclopride, Spirotetramat, Imidacloprid are suitable candidates for controlling grape leafhopper.