فهرست مطالب حسین کربلائی خیاوی

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.

Peach powdery mildew (Podosphaera pannosa) is one of the most economically destructive diseases of peach all over the world including Iran. In order to evaluate 11 genotypes of nectarines reaction against powdery mildew, an experiment was conducted in randomized complete block design with three replications during 2017-2018 in Agriculture and Natural Resources Research Station in Meshginshahr. The research was conducted in two conditions of natural infection and artificial inoculation. Cultivars included Independence, Stargold, Sangold, Sangold, Sanking, Giuta, Shabrang Karaj, Ghermeze Paeeze Karaj, Vega, Orion, Jiova and Veinberger. Evaluation of different cultivars of nectarine reaction to powdery mildew was conducted follow 0: Immune, 1: Very resistant 2: Resistant 3: Medium resistant 4: Sensitive and 5: Very sensitive. The results of two-year evaluation showed that there were significant differences between the degrees of resistance among the treatments. Comparison of means showed that the cultivar Veinberger in resistant and Stargold, Sangold, Sangold, Sanking, Giuta, Shabrang Karaj, Ghermeze Paeeze Karaj, Vega, Orion, and Jiova were in medium resistant cultivars. The results of the current study could be used in management of peach powdery mildew.

Powdery mildew is one of the most important diseases of apple globally and is caused by the fungus Podosphaera leucotricha. The aim of this study was to determine the efficacy of the fungicides Boscalid + Pyraclovastrobin (Bellis®; WG, 38%) with the doses of 0.4, 0.7 and 1 ml L-1 compared with the fungicides Tri-floxystrobin + Fluopyram (Luna Sensation®; SC, 500) with the dose of 0.2 ml L-1, Tri-floxystrobin (Flint®; WG, 50%) with the dose of 0.2 ml L-1 and Tri-floxystrobin + Teboconazol (Nativo®; WG, 50%) with  the dose of 0.2 ml L-1 to control the apple powdery mildew disease. The experiment was carried out in Ardabil province in a randomized complete block design (RCBD) with 8 treatments and 4 replications in 2019-2020. Control treatments were with water spraying and without any spraying Treatments were applied in the spring in three stages (full green bud stage, pink flower stage and 10 days after the 2nd spraying). Ten days after the first symptoms of the disease were observed in the control treatments, samples were taken from the sheets and the disease incidence and disease severity percentages were calculated. The results showed that the highest rate of control (80%) of apple powdery mildew disease was related to Luna Sensation® (0.2 ml L-1). Then   the fungicide treatment of Bellis® (1 ml L-1) had the highest rate of control of the disease (76%) and the treatments of Flint® (0.2 ml L-1), Bellis® (0.7 and 0.4 ml L-1) and Nativo® (0.2 ml L-1) were ranked next in this regard. The efficacy of the new fungicide Bellis® at the rates of 1 and 0.7 ml L-1 was 76 and 60%, respectively. Since both the doses of Bellis® are effective in controlling the disease, therefore, to protect the health of the fungicide users, the consumers  of the products and the environment as well as reduction in costs, the preferred dose was chosen as 0.7 ml L-1.

Fusarium head blight (FHB) is one of the most important diseases of wheat that is a suitable disease for forecasting. In order to determine the statistical relationship among disease occurrence and weather and crop variables, this study was conducted in Golestan, Mazandaran and Ardabil provinces during 3 years (crop years 2016-17, 2017-18 and 2018-19). Crop characteristics and disease severity were recorded in wheat fields around meteorological stations. Nine weather data was received from the stations as daily data and converted to 30 periodic variables. Integrating flowering start date and anthesis length in different years and regions calculated as 11 time and meteorological calendar variables and used in statistical analyses. Results of correlation tests of these variables with disease showed that the best window for disease prediction was B020 (20 days before anthesis) and ATX (average of maximum temperature), RD (number of rainy days), DD (number of dry days), ASHTR (average of special hydrothermal ratio) and NP80 (number of days with rain and relative humidity > 80%) showed the highest correlation with disease. Results of logistic regression and discriminant analysis for the selected variables as one, two and three showed that ATX was the best individual variable, and the best combination of two variables was ATX + NP80 and adding ASHTR to them did not cause significant increase in prediction efficacy. Therefore, logistic regression and discriminant analysis model of ATX and NP80 in 20 days before anthesis, introduced as the best model for forecasting wheat FHB.

Apple (Malus domestica, Borkh) is considered one of the most common popular and favorite deciduous fruit trees cultivated in Iran. Various harmful factors affect the performance of this fruit. Apple powdery mildew disease is one of the most important apple diseases that has a worldwide distribution and causes disease and is caused by the fungus Podosphaera leucotricha Ell. Et Ev. This fungus is an obligate parasite and it can attack to leaves, flowers, fruits and twigs. In the beginning of spring the disease appeared on leaves which are the most susceptible organs. The disease appears on the upperside of infected leaf as powdery white lesions and eventually the infected part of leaf turn brown and infections on the underside of infected leaf result in chlorotic patches. Infected leaves become crinkle, curl and drop prematurely. Although blossom and fruit infections are less common, they are important because infected fruits are small and stunted if they do not drop. P. leucotricha survives the winter as mycelium in vegetative tissues or in infected flower buds. The primary infection starts when infected buds break dormancy and fungus resumes growth and colonizes developing shoots. Spores growing on infected shoots spread nearby and initiate secondary infections. Also it causes early loss of leaves and stop the growth of diseased branches and as a result, the loss of yield. In heavily infected trees, rust can be seen on fruit surface. Powdery mildew infection usually occurs at relative humidity above 70%, and on days when humidity is low, the infection usually occurs at night or in the early morning hours when the humidity is high. Although the use of effective fungicides can control the disease well but appearance of resistant strains of pathogens to reduce fungicide efficiency in controlling disease and producers' access to effective fungicides from various chemical groups, while helping gardeners to reduce the economic damage caused by the disease, reduces the possibility of pathogen resistance to fungicides. The aim of this study was to determine the efficacy of Boscalid + Pyraclovastrobin (Bellis ® WG38%) (Manufactured by BASF Co.) (With doses of 0.4, 0.7 and 1 ml L-1) compared with Tri-floxystrobin + Fluopyram (Luna Sensation ®) (with a dose of 0.2 ml L-1), Tri-floxystrobin (Flint ® WG50%) (0.2 ml L-1) and Tri-floxystrobin + Teboconazol (Nativo ® WG50%) (With a dose of 0.2 ml L-1) to control apple powdery mildew disease.
For the experiment, the apple orchard of Golden Smooth cultivar with a history of powdery mildew in Ardabil province was selected. The experiment was carried out in a randomized complete block design (RCBD) with 8 treatments and 4 replications. Control treatments were without any spraying and with water spraying. Treatments were applied at three stages (full green bud stage and followed up at pink flowers stage and 10 days after the 2nd spraying). Ten days after the first symptoms of the disease were observed on the control treatments, samples were taken from the sheets and the percentage of the disease incidence and disease severity percentage were calculated. After calculating the incidence and disease severity of apple powdery mildew for each plot, the corresponding values in SAS statistical software were analyzed and the means of both traits were compared by Duncan's multiple range test at one percent probability level.
The results of analysis of variance of the data obtained from the evaluation of the leaves of the treated trees showed that the effect of treatments on reducing the percentage of disease severity and disease incidence is statistically significant. The results showed that Bellis ® fungicide with a concentration of 0.1 and 0.7 ml L-1, Luna Sensation ® 0.2 ml L-1, Nativo ® 0.2 ml L-1 and Flint ® with a concentration of 0.2 ml L-1 had a high efficiency of controlling apple powdery mildew disease. The efficacy of new Bellis ® fungicide with concentrations of 1 and 0.7 ml L-1 was 76 and 60 percent, respectively. According to the obtained results, Bliss fungicide with a dose of 0.4 per thousand had poor efficacy in controlling the severity and occurrence of the disease and was not statistically significantly different from the control treatments. The results also showed that there was no significant difference between the control treatments (treatment with water spraying and treatment without spraying).
Because both Bellis ® concentrations are effective in controlling the disease, therefore in order to protect the health of the fungicide users, the consumer of sprayed products and the environment as well as reduction in costs, the preferred dose is 0.7 ml L-1.

 The stem rust of wheat (Puccinia graminis f.sp. tritici) is one of the most important diseases of wheat in Iran causing severe yield loss in some years in the case of favourable condition for disease epidemic. In the recent years, a new race of stem rust (Ug99) and its new variants have been emerged, which are virulent on most resistance genes, such as Sr31, Sr38, etc., and have potential to spread rapidly and cause severe yield loss. The Ug99 race was first reported in 2009 from Lorestan and Hamadan provinces of Iran.Materials and

Results of a recent study conducted during 2011-2013 in Iran showed virulence on Sr36, Sr38, SrMcN and SrTmp genes and since, these genes have been used widely in genotypes resistant to Ug 99, there is a possibility of breakdown of these genes in Iran. Therefore, genetic variability of pathogen should be continuously investigated and resistance sources should be developed based on this information. For achieving this aim, 56 stem rust differential cultivars/lines obtained from the Cereal Research Center, Manitoba State, in Canada were planted in Ardabil Province, northwestern Iran under natural field conditions. The seeds of each cultivar/line were planted in two rows with 1 m of length and were irrigated every 10 days to promote disease development. Disease severity and type of infection of each cultivar/line were recorded based on the standard protocol at late flowering stage.

In the first year, the disease was developed only in Ardabil region. The SrMcN gene was the most susceptible gene, however, there was no virulence on Sr5, Sr21, Sr9e, Sr7b, Sr11, Sr6, Sr36, Sr9b, Sr30, Sr9a, Sr9d, Sr24, Sr31, Sr38, Sr8b, Sr9h, Sr12, Sr16, Sr19, Sr20, Sr22, Sr26, Sr27, Sr28, Sr32, Sr37, Sr39, Sr40, Sr41, Sr42, Sr43, Sr44, Sr45, Sr47, Sr50 ,and Sr53 genes. Other genes were moderately susceptible to virulence. In the second year, the disease was also developed.  SrMcN, Sr9h, and Sr42 genes were the most susceptible genes. However, no virulence was observed on Sr24 and Sr47 genes. The genes of Sr31 and Sr36 were resistant and susceptible, respectively. It seems that Sr36 and Sr38 genes have no potential to be used in breeding for achieving resistance against stem rust disease in Iran. However, Sr24 and Sr47 genes, which were resistant in the study area, are recommended to be incorporated in breeding wheat for obtaining resistance against stem rust disease. In addition, Sr31, Sr26, Sr27, and Sr28 genes, which were relatively resistant in most areas, were found to have potential to be combined with Sr24 and Sr47 genes in wheat breeding programs.

Stem or black rust caused by Puccinia graminis f. sp. tritici (Pgt) is one of the most common and harmful wheat diseases in Iran and worldwide. Under favorable conditions and the formation of the disease pyramid, the pathogen can destroy the wheat crops in a short time. Pgt has high genetic variability in the population structure due to the completion of the sexual cycle, which causes the creation of new races (race diversity) with a completely different pathogenicity pattern. TTKSK (Ug99) is one of the most critical race of Pgt that has appeared in recent decades and has caused much damage to wheat crops worldwide. This race had identified and reported in the country. However, the safest and at the same time most cost-effective way to manage and control this disease is to use genetic resistance. Accurate knowledge of the genetic structure of the pathogen population (existing races) in each region and knowledge of the virulence factors (genes) of stem rust races is the first step and similar to the roadmap to achieve effective and stable genetic resistance. One way to study the trend of changing pathogenicity patterns of races in each region is to observe virulence factors on stem rust differential genotypes in a trap nursery. For this purpose, virulence factors of Pgt races and the effectiveness of resistance genes in international differential genotypes investigated for three consecutive years (2017-2020) in the Ardabil province.

Powdery mildew caused by Podosphaera pannosa is one of the most important diseases of peaches and nectarines worldwide, including Iran. The aim of this research was to investigate the response of peaches and nectarines under cultivation in Iran to the disease.

Reaction of ten peach cultivars vs. Robin, Early Red, Red Top, Shasta, Amesdn, Velvet, Anjiri, Paeizeh, Dixi Red, and Sun Crest, and ten nectarine cultivars vs. Independence, Stargold, Sangold, Sanking, Giuta, Shabrang Karaj, Vega, Orion, Jiova and Veinberger were evaluated for disease in natural and artificial infection conditions in two experiments in a randomized complete block design with three replications over two years at the Meshgin Shahr Agricultural and Natural Resources Research Station.

Analysis of variance of experimental data showed that there was a significant difference between cultivars of each plant at a probability level of 1%. Peach cultivars Anjiri and Red top were very resistant, Velvet, Shasta and Early red ‎were resistant; Amesdn, Dixi red and Robin were moderately resistant; Sun ‎crest was susceptible and Paeizeh was in very susceptible. Weinberger nectarine cultivars were resistant and Independence, Stargold, Sanking, Giuta, Shabrang Karaj, Vega, Orion and Jiova cultivars were semi-resistant and Sangold was very susceptible to disease.  

Eighty percent of the studied peach cultivars are very resistant to semi-resistant and 20% sensitive and very sensitive, 90% of the studied nectarine cultivars are resistant to semi-resistant and 10% susceptible to powdery mildew. Findings of this research should be considered in the management of peach and nectarine powdery mildew.

Apple scab disease is one of the most important diseases of apple worldwide. Due to its high injury levels use of chemical pesticides for its management is inevitable. In the present study, the efficacy of myclobutanil (Atis®) in comparison with common fungicides including Captan (Captan© WP 50%), Trifloxystrobin(Flint© WG 50%), Trifloxystrobin + Tebuconazole (Nativo© WG 50%), Trifloxystrobin + Fluopyram (Luna Sensation© 500SC) was evaluated against apple scab disease. The experiment was carried out in a Randomized Complete Block Design with 9 treatments and 4 replications in Kohgiloyeh and Boyerahmad (yasuj) and Ardabil (Ardabil) provinces. Treatments included 0.142, 0.228 and 0.314 ml L-1 of  Atis®, 0.2 ml L-1 of Flint®, 0.2 ml L-1 of Nativo® , 0.4 ml L-1 of Luna Sensation®, 3 g L-1 of Captan®, and controls (without any spraying and with water spraying). Treatments were applied at three stages (silver tip stage which followed up at the end of flowering stage and 14 days after the 2nd spraying). The incidence, severity of the disease and mean comparisons were calculated and analyzed. Results show that fungicides treatments were significantly different from both control treatments. The results of the experiments in both locations show the efficacy of Atis at the rate of 0.314 and 0.228 ml L-1 in Yasuj was 97% and 88% and in Ardabil it was 62% and 55% respectively. Similarly, the efficacies of Luna Sensation at the rate of 0.4 ml L-1 and Nativo at the rate of 0.2 ml L-1 were 90% and 86% in Yasuj and 64% and 55% in Ardabil respectively. In conclusion, Atis at the rates of 0.314 and 0.228 ml L-1, Luna Sensation at the rate of 0.4 ml L-1 and Nativo at the rate of 0.2 ml L-1 had the highest efficacy against the apple scab disease.

Most of new acaricides evaluation were demanded against apple mite pest’s orchards in Iran. Effects of flufenzin 200 SC doses (0.2 and 0.3ml/lit) against Panonychus ulmi and Tetranychus urticae in apple orchards of Ardebil, West Azerbaijan, Khorasan Razavi and in Esfahan provinces were investigated during 2014 respectively. Other registered acaricides such as Spirodiclofen 240 SC, bifenazate 24% SC, fenpropathrin 10% EC, fenproximate 5% SC along with1.5% liquid detergent soap, water sprayed in control treatment were used in this study. Random apple leaves sampling at weekly interval followed from middle month of May and by observing mean 5 active mite stages on 30% of the collected leaves, treatments carried out at early morning hours. Efficiency of each treat done by random 40 leaves from middle part of apple trees collected at interval of one day before and 3,7,14, 21 days after treatment respectively. Mean mortality% analysis done by SAS software and ranked them according Duncan method. The higher P. ulmi mortality% by 0.2 ml/l of flufenzin dose treat recorded 92.45% and 95.82% at 3rd and 7th days after in Ardebil and reduced to 55.79% at 21st day respectively. Maximum P. ulmi mortality% caused by 0.3 ml/l of flufenzin dose recorded 86.47% and 81.79% at 14th and 21th days after in Mashhad area and on T. urticae observed between 66.07% to 72.17% during 3rd to 21st days after treatment in Esfahan. Highest mite pest control among registered acaricidal received for spirodiclofen acaricide and effects of all of them in comparison to earliest record found in reduction. Results indicated that by 480 g a.i. of flufenzin spraying in hectare under low mite pest incidence effective control in apple orchard expected.

European red mite (Panonychus ulmi (Koch)) and two-spotted spider mite (Tetranychus urticae Koch) are the two major pests of deciduous trees and most of the acaricides used in the control of them in apple orchards of Iran. The early of these two mite damages on leaf chlorophyll contents caused plant retardation, reduce fruit size and quality in apple production. Extensive mite pest damages during the middle of spring and summer months not only caused complete leaves shedding but side effects of this unusual condition imposed shortages of nutritional on vigorously of infested apple trees in next year on apple production also. Most of the new acaricides introduced and registered here in the last two decades demanded and evaluated against apple mite pests. Reduce the hazardous risk of synthetic acaricides application, so many efforts since 1995 undertaken since 1995 for sustainable mite pest’s management and keeping environmental and natural enemies safer in apple orchards. Evaluation of organic pesticides in developed countries in control of apple pests received more attention mostly to overcome spider mite pest damages in the world. In Iran, the only sulfur powder was tested in 1954 against citrus russet mite and no other mineral as an acaricide tested on apple mite pests in Iran. In this study, for the first time, the effect of Kaolin doses investigated on active stages of European red mite in four major apple growing orchards of Iran. Concerned literature survey indicated that this the first in depended kaolin effects report from Iran.

Different kaolin doses (3, 4 and 5%) against Panonychus ulmi infested apple orchards during investigated 2014. Effect of this pesticide was compared with registered acaricides such as Envidor (spirodiclofen 240 SC), floramite (bifenazate 24% SC), Danitol (fenpropathrin 10% EC), Ortus (fenpyroximate 5% SC), 1.5% detergent dishwashing along with water sprayed on apple trees as in uncontrolled treatment. Experiments conducted in different provinces of Iran (West Azerbaijan, Esfahan, Ardebil and Khorasan Razavi provinces during 2014). Treatment effectiveness was determined by random 40 apple leaves collected at the interval of one day before and 3, 7, 14 and 21 days after treatments. Active mite stages on the upper side of the apple leaf counted with the help of a stereomicroscope. Collected alive mite raw data from each treatment at different interval times, converted into morality% by Henderson-Tilton formula. Mean mortality% analysis variance done with SAS software. Grouping and ranking effects of each treatment carried out by DUNCAN methods.

Mite mean density before treatments on apple leaves among treatments found varied during 2014 in different provinces. The highest mean of mite out of 40 leaves before treatments in West Azerbaijan, Esfahan, Ardebil and Khorasan Razavi provinces recorded 11.60±0.28, 13.52±1.29, 11.85±0.32 and 4.75±0.15 respectively with total apple leaves infestation of 65 to 80% in all provinces. Lower doses (3 and 4%) of kaolin pesticides in the control of mite pests in all experimental stations except in Ardebil observed very weakly and less than 50% up to 14 days after. The highest mite mortality% time up to 7 days after treatments for 5% kaolin dose recorded 75.97% and 78.70 up to 7 days in Oromia and Ardebil and up to 14 days after observed 66.68%, 75.23% in Esfahan and Khorasan Razavi provinces respectively. A sharp reduction in apple mite pest control recorded at 21 days sampling interval for kaolin 5%. All kaolin doses sprayed on apple trees found without phytotoxicity during the hot and dried period of sampling time in all places. Expected control with 5% kaolin application at the early stages of P. ulmi activity for a once during the growing season is possible.

Application 5% kaolin at the lower incidence of Panonychus ulmi for once during the growing season in apple orchards recommended.

An experiment was conducted to evaluate the effect of different common herbicides on soybean yield and yield components. Experiment was carried out using a randomized complete block design (RCBD) with three replications at the Agricultural and Natural Resources Research Center of Moghan, Ardebil, Iran during 2017-2018. Treatments were the application of ethalfluralin, imazethapyr, trifluralin, metribuzin, bentazone, and alacolor herbicides and with and without hand weeding control. The results of variance analysis showed that the treatments had significant differences in herbicide efficiency, weed density and total dry weight. One month after herbicides spraying, trifluralin and ethalfluralin had the highest effect on the weed control; however, two months after herbicides spraying, all other treatments also showed their control effects and all herbicides were located in same statistical group. In this study, all herbicides treatments significantly reduced the density and dry weight of weeds compared to control; however, their effect was less than hand weeding. The number of pods per plant, biological and grain yield and soybean protein content percentage were significantly affected by all treatments; however, the other traits including plant height, growth period, chlorophyll index, 1000-seed weight, and grain oil percentage were not significantly different. The highest number of pods per plant (333.92) and grain yield (2792 kg/ha) were obtained in hand weeding treatment. Among the herbicides treatments, the application of ethalfluralin had the highest seed yield (1896 kg.ha-1</sup>). Generally, based on the results of this study, application of 2 L.ha-1</sup> ethalfluralin could be recommended for effective weed control in soybean production systems.

Hypericum perforatum L. (St. John's wort) is a perennial herb which contains precious metabolites such as hypericin, pseudo-hypericin and hyporforin widely used in the treatment of mild to moderate depression.  In order to evaluate light density (three levels including full light condition, 75% and 50% of full light intensities) on plant height, gland number per leaf, stomata number, chlorophyll content, fresh and dry weight, as well as hypericin production of Topaz cultivar and Mishu ecotype of H. perforatum under hydroponic conditions in the greenhouse, an experiment was carried out as split plots based on randomized complete blocks design with three replications at the University of Tabriz in 2017. The chlorophyll and hypericin contents were used by spectrophotometry. The results showed that the light density significantly affected on fresh and dry weight, plant height, gland number per leaf, chlorophylls a and b, photosynthesis and total hypericin content in the H. perforatum. The highest fresh and dry weight, gland number per leaf, stomata number, photosynthesis and total hypericin content were belonged to the full light conditions (100% light). The highest plant height, chlorophyll a and b were belonged to the 50% of prevalent light intensity. The results indicated that Topaz cultivar is better than Mishu ecotype. In conclusion, increasing hypericin content in Hypericum perforatum by managing of light intensity is possible

Abstract In order to evaluate the effect of Fusarium verticillioides on seed yield, catalase (CAT) activity on polyacrylamide gel and quantum yield of maize line, a factorial experiment based on randomized complete block design with five replications during 2017 growing season at the Payame Noor University, Mamaghan branch was performed. The experimental factors were two maize lines (B73 and MO17) and two levels of F. verticillioides (control and fusarium contamination). The results indicated that Fusarium verticillioides reduced seed yield, but enhanced CAT acivity in two maize lines. Further more, minimum fluorescence (Fo) in MO17 decreased, and increased in B73. Water splitting complex at donor side of PSII (FV/Fo) in B73 was increased, but was decreased in MO17. The level of maximum fluorescence (FM) in both line decreased. The energy necessary for closing reaction centers in PSII (Sm) and number of the QA reduction during fluorescence from Fo until FM (N) in MO17 were increased, but were decreased in B73. The results of this study revealed++ using from the chlorophyll a fluorescence can be a rapid and non-destructive method for evaluation of the maize reactions to injures caused by fusarium fungi infections.

Cereal cyst nematodes (CCN), Heterodera species, are important parasitic nematodes of cereal. Potato cyst nematodes (PCN), Globodera species, are also serious pests of potato world-wide. Continuous monitoring of these nematodes is necessary to prevent their damage to their host plants. This study was conducted to determine the distribution and density of these nematodes in Ardabil province, northwest of Iran, where potatoes are planted in rotation with cereals.

One hundred and two soil samples were collected from potato fields in the suburbs of Ardebil, Nair and Namin cities in the first year, and 116 soil samples were collected from the wheat fields that were cultivated in the rotation with potato in the second year. The samples were transferred to the laboratory and examined for cyst nematodes. After isolating the cysts, identification of the species was performed based on morphological and morphometrical characteristics of the cysts and the second stage larvae.

Examination of the collected samples in both of two years indicated the presence of CCN in some soil samples, but PCN were not observed in none of the soil samples. The morphological and morphometrical data of isolated cereal cysts and comparison with valid identification keys led to the identification of Heterodera filipjevi. Mean numbers of the cysts with eggs and larvae in those samples that were collected in the first and second year were respectively 0.76 and 0.11 in 100 g of the soil. Wheat fields of Ardebil had the highest and fields of Nair had the least number of cyst nematode.  

The results of this study showed that some of the wheat fields in the province were infected with H. filipjevi and potato fields were not infected with any cyst nematode.

The present experiment in order to determine the pattern of weed emergence in potatoes was conducted in 2014- 2015 at two places in agricultural research stations Alarogh and Samian in the city of Ardabil- Iran. Each week after potatoes planting emergence weeds in the constant sampling units inside the plots were transported to the laboratory in order to count and separation based on the results of this research, sampled weeds included 10 species and 7 families the highest germination and emergence of weeds occurred on average in 2-4 weeks after potatoes planting that's mean after receiving the 137 to 329 degree-days growth By potato in Samian station and 105 to 254 degree day in Alarogh station but the highest weed density in both stations Alarogh and Samian belonging to the species of Amaranth and after the amaranth in Samian station the highest density belong to the mustard compared to other weeds but also in this test, like amaranth, the lambs quarters in the third week belongs to the highest germination and density and declined from the third week onwards germination of this species. Green foxtail weed density in both studied stations had the highest rates in the third and fourth weeks equivalent to receiving the 233 to 329 degree day for Samian station and 177 to 254 degree day for Alarogh station but perennial weeds, field bindweed maintaining an emergence almost in the entire period...

In order to evaluate 25 peach varietiesagainst powdery mildew an experiment was conducted in randomized complete block design with three replications under natural infection condition in the Meshginshahr Agriculture and Natural Resources Research Station during 2014 and 2015. The peach varietieswere consist of Robin, Red haven, Early red, Spring crest, Vesevio, Red top, J.H. Hale, Shasta, Early glo, Amesdn, Loring, Spring time, Velvet, Sudanell, sundance, Anjiri, Haj Kazemi, Paeizeh, Elberta, Baby gold7, Dixi red, Red skin, Sabz-e- Mashhad, Sun crest and July Elberta. Combined analysis of variance showed that disease severity of powdery mildew among varieties was significantly different at the 1% probability level. Based on mean comparisons, varietiesRed haven, Anjiri, Early glo, J. H. Hale, Loring, Red top, July Elberta, Velvet, Spring crest, Red skin, Shasta, Early red, Sudanell and Elberta had lower mean disease severity of powdery mildew on leaves compared to other varieties. Based on cluster analysis, varietiesEarly glo, J. H. Hale, Red haven, Anjiri, Loring and Red top were classified as very resistant and July Elberta, Vesevio, Elberta, Spring crest, Velvet, Shasta, Early red and Red skin as resistant varietiesto causal agent of peach powdery mildew.

Peach powdery mildew (podosphaera pannosa) is one of the most economically destructive diseases of grapevines all over the world including Iran. In order to evaluate the 25 genotypes of peaches reaction against powdery mildew an experiment was conducted in Randomized Complete Block Design with three replications during 2014-2015 in Agriculture and Natural Resources Research Station in Meshginshahr. The research was conducted in two conditions of natural infection and artificial inoculation. Genotypes included Robin, Red heven, Early red, Spring crest,Vesevio, Red top, J.H. Hale, Shasta, Early glo, Amesdn, Loring, Spring time, Velvet, Sudanell, Sundance, Anjiri, Haj kazemi, Paeizeh, Elberta, Baby gold7, Dixi red, Red skin, Sabz-e-Mashhad, Sun crest and July Elberta. The evaluate on different genotypes of peaches reaction to powdery mildew was don using Ivascu and Buciumanu (2006) as follow: 0: Immune, 1: Very resistant 2: Resistant 3: Medium resistant 4: Sensitive and 5: Very sensitive. The results of two year evaluation showed that there were significant differences between the degrees of resistance against the studied disease among the treatments. Comparison of means showed that the genotypes J.H. Hale, Anjiri, Loring, Red top, Red heven and Early glo very resistant; Vesevio, Elberta, Spring crest, Velvet, Shasta, Early red, Red skin and July Elberta in resistant; Baby gold7, Sundance, Amesdn, Haj kazemi, Spring time, Dixi red and Robin in medium resistant; Sun crest and Sudanell in sensitive and Sabz-e-Mashhad and Paeizeh were very sensitive genotypes.

In order to determine the most suitable dwarf rootstock for apple cultivar 'Red Deliciou's and optimal planting distances under climatic conditions of Meshginshahr region, this research was conducted as a split plot with randomized complete block design in three replications during two years. The two planting distances of 2 × 4 and 3 × 4 meter were as the main plot and three rootstocks MM106, M9 and M26 were as sub-plots were included in the test. Analysis of variances showed significant differences between years in terms of yield and flowers density; between the planting distances in terms of yield, fruit size and soluble solids concentration and flowers density; between rootstocks in terms of yield, fruit size, flower density and dry matter; and significant differences in yields between interactions of the planting distances × rootstocks, year × planting distances × rootstocks at 5% and 1% possibility levels. Apple CV. 'Red Deliciou's grafted on M9 rootstock in planting distances of 2 × 4 meter with 9.367 tons per hectare had the highest yield and was placed in group. Analysis of average effect of rootstock in fruit production showed that 'Red Deliciou's on M9 rootstocks produced the biggest fruit and had the highest density. Fruit size, flower density on tree and soluble solids concentration in the planting at a distance of 3 × 4 m were greater than that in 2 × 4 meter. In this study, apple fire blight disease was not observed in the treatments.

Nowadays, regarding better integrated weed management and its control, attention to weed biology is critical and should be accepted as a scientific activity in weed science society (Rashed Mohassel et al., 2001). Precise weed biology identification will lead to better management practices (Alebrahim etal., 2009; Pahlevani etal., 2007). To be successful, weed management programs based on weed ecology and biology, need to acquire the correct information about environmental factors such as temperature, humidity, and their effects on plant characteristics (Zand etal., 2007). In weed science, non-chemical weed management by physical methods is one of the best usable methods. The purpose of this study was to evaluate Gladiolus weed biology to develop techniques for sustainable management.
This research was done in the Faculty of Agriculture and Natural Resources laboratories at the University of Mohaghegh Ardabili. Treatments included: 1- Evaluating the effect of different temperatures (5, 10, 15, 20, 25, 30, 35 and 40 degrees centigrade) on the emergence of Gladiolus corms in a completely randomized design with 4 replications. 2- Evaluating the effect of different temperatures and drying periods on the emergence of wild Gladiolus corms as a factorial in a completely randomized design with 4 replications. The first factor was storage periods in an oven for 4 different periods (1, 2, 3 and 4 weeks). The second factor was oven temperature at 5 levels (20, 23, 25, 35 and 40 degrees centigrade). 3- Evaluating the effects of different temperatures and freezing periods on the emergence of wild Gladiolus corms as a factorial in a completely randomized design with 4 replications. The first factor was storage periods in an incubator for 4 different periods (1, 2, 3 and 4 weeks) and the second factor was freezing temperatures at 6 levels (0, -5, -10, -15, -20 and -25 degrees centigrade).
Results showed that among different temperature treatments, the corms emerged at 15-30ºC. The higher emergence percentage was 87.5% at 20ºC. By increasing water reduction in corms in the oven, emergence ability was reduced. Further, with a 36/25 percent water reduction in corms, emergence ability reached zero. Corm emergence ability was affected by temperature and oven storage length. The highest survival rates with 100% emergence was with a temperature between 20 -25ºC after being stored for 1-2 weeks in the oven. Results also showed that by increasing the freezing period and lowering the temperature, the survival of wild Gladiolus corms was reduced. Further, at temperatures of -15, -20 and -25ºC the emergence ability reached zero. The highest emergence rate was at 0 ºC with a 1 week freezing period.
In this experiment 20ºC, was the optimum temperature for emergence of corms. Generally, by putting corms in temperatures higher than 30ºC or lower than -10ºC, the emergence ability reached zero. Thus with no chemical treatment and just by using environmental conditions in cold and warm climates, this weed density will be reduced and sustainable management will be achieved.

Fungal diseases are a major problem in the cultivation of grapevine, Powdery mildew disease caused by plant pathogenic fungus, Erysiphenecator is one of the most important and destructive diseases of grape in many countries of the world including Iran. Due to extend viticulture area in Iran and the high prevalence of the grape powdery mildew in vineyards, application of sulfur based fungicides is mainly recommended for the disease control. This study was conducted aimed to investigate the effect of new formulations fungicide of sulfur SC 80% and penconazole EW 20% to control grape powdery mildew disease.
Material and The experiments were conducted on Askari cultivar as susceptible in Ardabil, KhorasanRazavi and Kohgiluye and Boyer-Ahmad provinces and in vineyards, which in previous years had a history of infected and trees were similar in age and growth conditions. Experiments were carried out in a completely randomized block design with four replications. Treatments were composed of penconazole EW 20% 0.125 ml L-1, sulfur SC 80% 2, 2.5 and 3 ml L-1 and control. The spray was carried out three times, including when the young shoots were between15 and 35cm, before falling flowers and stage of sours. One week after the last spray sampling of leaves and clusters was carried out in four directions main canopy trees randomly in each plot. Efficacy of treatments was evaluated based on infection severity found in 60 leaves and 12 clusters in per plot. To determine the amount of sugar and tartaric acid in the grape fruit, sampling of the healthy and infected clusters were carried out and healthy and infected the samples were then separated into a plastic bag and crushed. Then, the juice wasprepared (fruit juice was obtained from 700 g fruit in each sample).To determine the amount of sugar, hand-held refractometer was used and the amount of sugar was determined in healthy and infected fruit. For the determination of tartaric acid in grape juice titration using sodium hydroxide, 1.0 M was carried out.
To determine the yield of grapes per healthy and infected plants and determination of the quantity of the yield damage caused by the disease, after fruit ripening, all clusters of grapes were picked by hand and weighed. Then in each province data were transformed and statistical analysis of data using SAS software was carried out. The mean comparisons were conducted with Duncan's Multiple Range test and Fisher's Least Significant Difference (LSD) test at the 5% level.
Combined analysis of variance studied traits showed that between locations in terms of severity of disease in leaves and fruits, between treatment and locations and treatment interaction in terms of severity of disease in leaves and fruits, yield there was the significant difference. Analysis of variance amounts of sugar and acid concentration in the grapes in Ardabil (Meshginshahar) showed between treatments in terms of the amount of sugar and acid concentration in grape was observed the significant difference. According to the results sulfur SC 80% fungicide at concentrations of 2.5 and 3 per thousand the greatest effect in reducing the powdery mildew disease and increase yield and quality of grapes. Analysis of variance for amounts of sugar and acid levels in the grapes in Ardabil (Meshginshahar) showed highly significant differences among treatments in grape sugar and acid concentration at 1% level. Comparison of means indicated that control treatment (without spraying) had the highest concentration of sugar and acid. In this study, increasing the severity of the disease on the leaves and fruit tended to increased acid concentration in the fruit. In this study, the yield of the grape was decreased depending on the disease severity on the leaves and clusters. In this experiment, increasing the severity of the disease on the leaves and fruit tended to increased sugar amount. The intensity of infection was higher in the leaves and fruits as well as the amount of sugar in sugar increases that were consistent with findings of another researcher.
According to the results and taking into consideration environmental protection, the lowest intensity of infection in the leaves and fruit, the highest yield, the most normal sugar and acid concentration were on the treated plants with the sulfur concentration of 2.5 per thousand. According to the results of this study, spraying sulfur SC 80% in the control programs of the disease to prevent the emergence of resistant races of grape powdery mildew would be desirable.

Today, the use of cover crops by farmers has its own economical approval with the benefit of reducing herbicide application through improved soil conditions and crop yield. Among the various plants, rye is the most suitable for use as a cover plant due to its high biomass production and allelopathic compounds.
In order to the evaluate the effects of different levels of rye densities and planting dates on the density and biomass of weeds in a forage maize field, a factorial experiment was conducted with a randomized complete block design with three replications at the agricultural research station in Ardabil. The first factor was the rye planting date at an interval of 15 days: (25 April, 10 May, 25 May and 10 June). The second factor was the rye planting densities that included (0 kg, 80 kg, 120 kg, and 160 kg per ha). To investigate the effect of rye on density and weed biomass, a weed sampling was conducted in two stages. The first stage was done at 8 leaves of maize and the second was done a week before tasselling of maize on the basis of 0.5 by 0.5 meters. Also measured were ear weight, length, and diameter, and shoot fresh weight, stem diameter, and fresh forage yield of maize.
The results showed that the density and biomass of annual and perennial weeds were influenced by the main and interactive effects of the rye planting by date × plant density. Due to their allelopathic features, cover crops can control weed growth, bring about higher growth rates and rooting power, as well as help preserve the earth with suitable covering at early planting dates (Tobeh et al., 1999). In an experiment with soybeans, rye as a cover crop reduced weed biomass 60% to 90% due to its allelopathic effect (Ateh and Doll, 1996). In general, the first planting date of rye (one month prior to the planting of corn) had the greatest effect on reducing the density and dry weight of weeds. The first planting date by the third density, reduced the density of the annual weeds by 89% and its dry weight by 93%. Perennial weeds were reduced by 83 percent and their dry weight by 92 percent. In spring planting, because of a lack of rye vernalization, there would be no troublesome new weeds, because the plant cannot reproduce by itself within a few months in most areas. This disappearance of rye adds to the appropriate control of weeds. Weed control by rye leads to enhanced competitiveness of maize and increases forage yield, cob fresh weight, length, diameter, stem fresh weight, and the diameter of maize. The main effect of the density with the highest density of rye (third density), is that it is more likely to be competitive with maize, reducing the availability of nitrogen, the release of allelopathic materials and soil cooling. This resulted in significant reduction in maize yield components. The combination of the optimum planting date (third planting date) along with greater weed control, resulted in a significant increase in maize yield. Reduction of cover crops residue, especially small grains, is related to reduced nitrogen availability, reduced toxins and lower soil temperatures (Westgate et al., 2005; Norsworthy, 2004).
Together with the optimum planting dates and density, the use of cover crops, especially rye, is generally a good choice to control weeds in corn fields.

Most farmers use various management strategies to minimize weed damage, and such management practices can have direct or indirect impacts on biodiversity in agricultural ecosystems (Koocheki et al, 2006). Use of various mulch and tillage methods with the application of herbicides causes greater confidence in effective weed control and can be used as one of the major methods of weed control in potato crop (Bellinder et al, 2000). The aim of this study was the evaluation of weed composition under the influence different kinds of weed management methods in potato crop.
The experiment was performed in 2015 on two locations at the agricultural research stations of Alarogh and Samian in Ardebil Province in a randomized complete block design with three replications. The treatments included 1) spraying Trifluralin between potato rows, 2) spraying Metribuzin between potato rows, 3) cultivator practice between planting lines, 4) usage of plants containing wheat stubble, 5) usage of plants containing Canola stubble, 6) usage of black polyethylene mulch, 7) usage of transparent polyethylene mulch and 8) control (no weed control in all growth duration) treatment.
From 12 weed species observed in this study, Common Amaranth (Amaranthus retroflexus), Common lambsquarters (Chenopodium album), Bindweed (Convolvulus arvensis), Green foxtail (Setaria viridis), Prickly lettuce (Lactuca seriola), Russian knapweed (Acroptilon repens) and Milk thistle (Sonchus arvensis), were dominant with the highest rate of weed prevalence. The averages of any ShannonWiener and Simpson indices were changed in both locations so that only the diversity of the Shannon-Weaver index showed a statistically significant difference with change in the kind of weed management. The greatest diversity of both indices was observed in weed infested treatment. Based on the results of Baskin et al (2004) and Milberg (1997), lack of weed control in farmland or fallow land increased weed density and caused an increase in weed density and can also have an effect on species diversity. Based on the Shannon-Wiener index the treatments comprising the use of Trifluralin, cultivators and transparent plastic with values of 1.11, 1.04 and 0.99, respectively, after the weed infested treatment had the highest species diversity. The lowest number of weed species based on the Shannon-Wiener and Simpson indices, similarly, was related to the treatments of canola stubble mulch, Metribuzin herbicide and black plastic mulch, respectively. Hence, with potato weed density at both stations being significantly under the influence of experimental treatments, the mulch, herbicide and cultivator treatments had a significant effect on potato weed density in both locations so that the lowest density of weeds was obtained in wheat stubble mulch and canola stubble mulch. The density of Common Amaranth, Common lambsquarters and Bindweed species, all important weeds, decreased in all mulch, cultivation and herbicide treatments as compared to the weed infested treatment. The highest Common Amaranth density was observed in the treatments of black plastic mulch, Trifluralin and transparent plastic mulch, respectively. Common lambsquarters had the highest density under Metribuzin herbicide treatments.
In this study, density of annual weeds was higher than that of perennial weeds; in other words, the highest density of weeds was related to annual weeds. But canola stubble reduced weed density and biomass more compared with the control to the amount of 83 and 81 percent, respectively, and the wheat stubble application reduced weed density and weed biomass to the amount of 79 and 84 percent, respectively. This shows that the use of herbicides, plastic and plant mulch and cultivator can significantly reduce weed density and biomass.