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Different cultivars of a host plant can have an important effect on the behavioral charectristics of natural enemies. In this study, the effect of three wheat cultivars (Ehsan, Morvarid, and Tirgan) on functional responses of 4th instar larvae and adult males and females of Hippodamia variegata Goeze on different densities (2, 4, 8, 16, 24, 32, 64, 96, 128, and 160) of 4-d-old nymphs of Schizaphis graminum Rondani was studied. The experiments were conducted at 25±2 °C, 65±5 RH and 16L:8D h photoperiod. The logistic regression analyses revealed that the functional responses of different growth stages of H. variegata to S. graminum on differen wheat cultivars were type II. According to the results, the highest attack rate was estimated for 4th instar larvae of H. variegata on Ehsan and Tirgan cultivars (0.152 and 0.154 h-1, respectively). Also, the lowest handling time (0.127 h) was valued for 4th instar larvae on Ehsan cultivar. The predation rate of 4th instar larvae of H. variegata was also highest on Ehsan cultivar. The results of this study revealed the high efficiency of 4th instar larvae of H. variegata in feeding on S. graminum on Ehsan cultivar followed by Tigasn and Morvarid cultivars. Similar results were obtained for adult femles and males of the predator. However, further studies are necessary to evaluate the effect of these cultivars on searching bahavior and consumption rate of different stages of H. variegata on S. graminum under natural conditions. [ABSTRACT FROM AUTHOR]

Different cultivars of a host plant can have an important effect on the behavioral charectristics of natural enemies. In this ‎study, the effect of three wheat cultivars (Ehsan, Morvarid, and Tirgan) on functional responses of 4th instar larvae and adult ‎males and females of Hippodamia variegata Goeze on different‏ ‏densities (2, 4, 8, 16, 24, 32, 64, 96, 128, and 160) of 4-d-old ‎nymphs of Schizaphis graminum Rondani‏ ‏was studied. The experiments were conducted at 25±2 ˚C, 65±5% RH and 16L:8D h ‎photoperiod. The logistic regression analyses revealed that the functional responses of different growth stages of H. variegata ‎to S. graminum on differen wheat cultivars were type II. According to the results, the highest attack rate was estimated for 4th ‎instar larvae of H. variegata on Ehsan and Tirgan cultivars (0.152 and 0.154 h-1, respectively). Also, the lowest handling time ‎‎(0.127 h) was valued for 4th instar larvae on Ehsan cultivar. The predation rate of 4th instar larvae of H. variegata was also ‎highest on Ehsan cultivar. The results of this study revealed the high efficiency of 4th instar larvae of H. variegata in feeding ‎on S. graminum on Ehsan cultivar followed by Tigasn and Morvarid cultivars. Similar results were obtained for adult femles ‎and males of the predator. However, further studies are necessary to evaluate the effect of these cultivars on searching ‎bahavior and consumption rate of different stages of H. variegata on S. graminum under natural conditions. ‎

Iran is the thirteenth country in terms of wheat production in the world. Kermanshah Province is known as the west agricultural pole of the country. It has about 700,000 hectares of agricultural land, and more than 173,000 hectares of high quality water land. Irrigation is one of the most important effective factors in grain production in hot and dry climates. Research has shown that the use of modern pressurized irrigation systems reduces water consumption and increases the water use efficiency. Considering the issue of water shortage that has been raised in the country in recent years, The simultaneous investigation of the effects of sprinkler and strip drip irrigation systems in three wheat cultivars including Baharan, Rakhshan and Heydari cultivars on yield, yield components and water use efficiency in this province seemed necessary.This research was carried out in the research farm of ACECR, Kermanshah province unit during 2021. Wheat seeds of Baharan, Rakhshan and Heydari cultivars were cultivated on 08/30/2020 after health control and detoxification. This study was conducted in the form of a split plot in a randomized complete block design with three replications. In the main plots, the irrigation methods including sprinkler and strip drip irrigation were evaluated and in the sub-plots, wheat cultivars including Baharan, Rakhshan and Heidari were evaluated. From each treatment, one square meter of samples was taken from the middle of the plot. These samples were placed separately in special bags (by installing specifications on each sample) and were immediately transferred to the laboratory. According to the dimensions of the plots (60 m2), during the growth period of the wheat plant, the irrigation amount was 633.50 mm in sprinkler irrigation method and 436 mm in strip drip irrigation method. Finally, after data collection, statistical analysis, including an analysis of variance and comparison of means, was performed using Duncan's multi-range test at a five percent probability level with SAS Ver 9.4 software.Based on the results of the statistical analysis of the irrigation method, there was a significant effect on the characteristics of plant height, number of seeds per spike, seed yield, biomass yield, and water use efficiency of the crop. Additionally, the effect of cultivars was significant in plant height, number of seeds per spike, seed yield, biomass yield, and water use efficiency. The results of the analysis of variance showed significant effects of irrigation method and cultivars for crop yield traits and water use efficiency. The comparison of means revealed that the highest yield of 9458 kg/ha was observed in the strip drip irrigation treatment in Baharan cultivar, which had a statistical difference with the sprinkler irrigation treatment in similar cultivars. Furthermore, the sprinkler irrigation treatment in Heydari cultivar with a yield of 6539 kg/ha had the lowest yield. Based on the obtained results, the highest and lowest water use efficiency productivity with values of 2.13 and 1.03 kg/m3 were observed in the strip drip irrigation treatments of Baharan variety and sprinkler irrigation of Heydari variety, respectively. The results of the research showed that the use of strip drip irrigation method compared to the sprinkler irrigation method in Baharan, Rakhshan, and Heydari cultivars resulted in an increase of 20.07%, 29.76%, and 20.50% in crop yield, respectively.Optimum use of water seems necessary considering the climatic conditions of the country and the recent droughts. One of the important and effective solutions is to use modern irrigation systems. The results revealed that the use of different irrigation systems caused a significant difference at the levels of 1% and 5% on the yield and yield components of wheat in investigated cultivars. Based on the results in the tape irrigation method, the yield increased in most of the analyzed parameters compared to the sprinkler irrigation method. The results exhibited that, the use of tape method saved water consumption by 31% and increased the yield of the product and finally increased the water efficiency compared to the sprinkler irrigation method.

Introduction Iran is the thirteenth country in terms of wheat production in the world. Kermanshah Province is known as the west agricultural pole of the country. It has about 700,000 hectares of agricultural land, and more than 173,000 hectares of high-quality water land. Irrigation is one of the most important effective factors in grain production in hot and dry climates. About 90% of the country's renewable water is consumed in the agricultural sector, and the lack of water is the main factor limiting production. Research has shown that the use of modern pressurized irrigation systems reduces water consumption and increases water use efficiency. Considering the issue of water shortage that has been raised in the country in recent years, The simultaneous investigation of the effects of sprinkler and strip drip irrigation systems in three wheat cultivars including Baharan, Rakhshan and Heydari cultivars on yield, yield components and water use efficiency in this province seemed necessary. Methodology This research was carried out in the research farm of ACECR, Kermanshah province unit (located at 47 degrees and 6 minutes east longitude and 34 degrees and 26 minutes north latitude with 1320 Meters above sea level) year 2021. At the end of October 2020 year, plowing and preparation of the cultivation substrate was done by tractor. Based on the soil test results, 150 kg/ha of triple super phosphate fertilizer and 100 kg/ha of potassium sulfate were used at the same time as planting. The amount of 200 kg/ha of urea fertilizer was also distributed in several stages (50 kg/ha at the same time as planting and the rest in two stages, 100 kg/ha at the time of multi-leafing and 50 kg/ha at the beginning of stem growth) in the field. Wheat seeds of Baharan, Rakhshan and Heydari cultivars were cultivated on 08/30/2020 after health control and detoxification. This study was conducted in the form of a split plot in a randomized complete block design with three replications. In the main plots, the irrigation methods including sprinkler and strip drip irrigation were evaluated and in the sub-plots, wheat cultivars including Baharan, Rakhshan and Heidari were evaluated. From each treatment, one square meter of samples was taken from the middle of the plot. These samples were placed separately in special bags (by installing specifications on each sample) and were immediately transferred to the laboratory. The investigated parameters included the number of seeds per spike, plant height, 1000 seeds weight, crop yield, biomass yield, harvest index and, finally, water use efficiency. The average annual rainfall in the research area was 303 mm. According to the dimensions of the plots (60 m² ), during the growth period of the wheat plant, the irrigation amount was 633.50 mm in sprinkler irrigation method and 436 mm in strip drip irrigation method. Finally, after data collection, statistical analysis, including an analysis of variance and comparison of means, was performed using Duncan's multi-range test at a five percent probability level with SAS Ver 9.4 software. Results and discussion Based on the results of the statistical analysis of the irrigation method, there was a significant effect on the characteristics of plant height, number of seeds per spike, seed yield, biomass yield, and water use efficiency of the crop. Additionally, the effect of cultivars was significant in plant height, number of seeds per spike, seed yield, biomass yield, and water use efficiency. The results of the analysis of variance showed significant effects of irrigation method and cultivars for crop yield traits and water use efficiency. The comparison of means revealed that the highest yield of 9458 kg/ha was observed in the strip drip irrigation treatment in Baharan cultivar, which had a statistical difference with the sprinkler irrigation treatment in similar cultivars. Furthermore, the sprinkler irrigation treatment in Heydari cultivar with a yield of 6539 kg/ha had the lowest yield. Based on the obtained results, the highest and lowest water use efficiency productivity with values of 2.13 and 1.03 kg/m³ were observed in the strip drip irrigation treatments of Baharan variety and sprinkler irrigation of Heydari variety, respectively. The results of the research showed that the use of strip drip irrigation method compared to the sprinkler irrigation method in Baharan, Rakhshan, and Heydari cultivars resulted in an increase of 20.07%, 29.76%, and 20.50% in crop yield, respectively. Conclusions Optimum use of water seems necessary considering the climatic conditions of the country and the recent droughts. One of the important and effective solutions is to use modern irrigation systems. Therefore, this research was carried out in the research farm of ACECR, Kermanshah province unit during 2021 to assessing of the effect of irrigation systems on yield, yield components and water use efficiency in three wheat genotypes the results revealed that the use of different irrigation systems caused a significant difference at the levels of 1% and 5% on the yield and yield components of wheat in investigated cultivars. Based on the results in the tape irrigation method, the yield increased in most of the analyzed parameters compared to the sprinkler irrigation method. The results exhibited that the use of tape method saved water consumption by 31% and increased the yield of the product and finally increased the water efficiency compared to the sprinkler irrigation method. [ABSTRACT FROM AUTHOR]

This experiment was conducted in a greenhouse at Isfahan University of Technology, Isfahan, Iran in 2014 to evaluate 20 wheat cultivars (Navid, Pishtaz, Karaj, Kavir, Tajan, Karun, sholeh, Bahar, Khoshki 11, Gasparood, Sepahan, Sorkh tokhm, Chamran, Ghods, Shariar, Omid, Sistan, Alamut, Marvdasht and Shiraz) under two carbon dioxide concentrations (the ambient 360 and the enriched 700 µM) and two salinity levels (0 and 150 mM NaCl). Treatments were arranged as a factorial in a completely random design with three replications. The results showed that salinity decreased potassium concentration in shoots (27%) and roots (39%), chlorophyll a and b concentrations (27 and 30%, respectively), carotenoids concentration (21%), plant height (39%), leaf area (32%), root volume (40%), shoot and root dry weight (30% and 23%, respectively); however, it increased sodium concentration in the shoots and roots (36%). The extent of salt-induced decreases in the shoot dry weight of the evaluated cultivars ranged from 8 to 46%. Karaj and Marvdasht cultivars were the most and the least sensitive cultivars to salinity under both ambient and enriched carbon dioxide concentrations, respectively. The elevated carbon dioxide concentration increased potassium concentration in the shoots (except Sholeh, Ghods and Gasparood) and roots, chlorophyll and carotenoids concentrations, plant height, leaf area (except Shahriar), root volume, shoot (except Sistan and Omid), and root dry weight; however, it decreased sodium concentration in the shoots and roots. The highest and the lowest increases in the shoot dry weight under non saline condition were obtained for Karaj and Alamut (23 and 6%, respectively); under saline conditions, they were found in Chamran and Kavir (66 and 3%, respectively). The results obtained from this experiment showed that the elevated carbon dioxide concentration positively influenced the growth of most cultivars. This effect was more pronounced under saline conditions, indicating that carbon dioxide enrichment could alleviate, at least in part, the negative effects of salinity.

In order to study the effects of different levels of salinity on germination components of wheat cultivars, a factorial experiment was conducted based on a completely randomized design with three replications. Experimental factors were wheat cultivars at eight levels (Saysons, Gaspard, Finkan, MV-17, Chamran, Sardari, Atila-4 and Azar-2) and six levels of salinity (0, 25, 50, 100, 150 and 200 mM NaCl). The results indicated that salinity had significant effects on all of the traits studied (i.e., radicle length and dry weight, plumule length and dry weight, remaining seed weight after germination, seedling weight, the longest radicle and plumule, number of radicle per seed, ratio of radicle weight to plumule weight and rate, and uniformity and percentage of germination). All of these traits declined with an increase in the salinity (except the ratio of radicle weight to plumule weight, remaining seed weight after germination and seedling weight). The highest ratio of radicle weight to plumule weight, remaining seed weight after germination and seedling weight were recorded in the salinity of 200 mM NaCl. The cultivars showed significant effects on all of the traits studied (except remaining seed weight after germination and seedling weight). Chamran cultivar showed the highest number of radicle per seed, the ratio of radicle weight to plumule weight, rate and percentage of germination. The highest radicle length and the longest radicle were obtained from the Sardari cultivar while in Azar-2 cultivar it was vice versa in plumule. Atila-4 cultivar showed the highest radicle and plumule weight. It seems that compared with other cultivars, out of the cultivars studied, Chamran, Azar-2, Sardari and Atila-4 were more resistant to salinity stress. Highlights: Introduction of wheat cultivars with more tolerance to salinity conditions at germination stage. Study of eight different wheat cultivars in terms of germination indices under salinity stress conditions.

Drought stress is one of the most important factors in reduction of crops production. An experiment was conducted on 7 cultivars of wheat in randomized complete-block and split plot design with three replications in order to detect the tolerant cultivars against drought stress also Assessment the physiological and biochemical processes associated with drought tolerance to optimize the supplementary irrigation time. The mentioned experiments were performed under supplementary irrigation conditions at the stemming, boating and flowering steps also under non-irrigated condition. The experiments were done in two consecutive years (1394 and 1395) at Dehgolan field, depending on Faculty of Agriculture and Natural Resources, Kurdistan University. In the present study, peroxide-malondialdehyde level (MDA), total protein content, and the activity of catalase, ascorbate peroxidase, guaiacol peroxidase and superoxide dismutase were measured. Based on the results, a significant interaction was measured, in the most of attributes, between cultivar and supplementary irrigation. Compared to the control sample, Supplementary irrigation leads to decrease H2O2' content. The maximum values of H2O2 and MDA were measured for Aras, Abu Ghraib and Tamuz cultivars, respectivelywhile the minimum values of them were obtained for Azar-2. Curiously, supplementary irrigation caused to increase the activity of catalase, and superoxide dismutase for all cultivars also total protein content (except Aras cultivar) and ascorbate peroxidase (just for Axad 65, Rezgari, Smito and Azar-2 cultivars). According to the results, Axad 65, Rezgari, and Azar-2 cultivars in flowering stage could control exist conditions, with less energy consumption, through regulation and optimization their defense mechanisms. [ABSTRACT FROM AUTHOR]

This experiment was conducted in a greenhouse at Isfahan University of Technology, Isfahan, Iran in 2014 to evaluate 20 wheat cultivars (Navid, Pishtaz, Karaj, Kavir, Tajan, Karun, sholeh, Bahar, Khoshki 11, Gasparood, Sepahan, Sorkh tokhm, Chamran, Ghods, Shariar, Omid, Sistan, Alamut, Marvdasht and Shiraz) under two carbon dioxide concentrations (the ambient 360 and the enriched 700 μM) and two salinity levels (0 and 150 mM NaCl). Treatments were arranged as a factorial in a completely random design with three replications. The results showed that salinity decreased potassium concentration in shoots (27%) and roots (39%), chlorophyll a and b concentrations (27 and 30%, respectively), carotenoids concentration (21%), plant height (39%), leaf area (32%), root volume (40%), shoot and root dry weight (30% and 23%, respectively); however, it increased sodium concentration in the shoots and roots (36%). The extent of salt-induced decreases in the shoot dry weight of the evaluated cultivars ranged from 8 to 46%. Karaj and Marvdasht cultivars were the most and the least sensitive cultivars to salinity under both ambient and enriched carbon dioxide concentrations, respectively. The elevated carbon dioxide concentration increased potassium concentration in the shoots (except Sholeh, Ghods and Gasparood) and roots, chlorophyll and carotenoids concentrations, plant height, leaf area (except Shahriar), root volume, shoot (except Sistan and Omid), and root dry weight; however, it decreased sodium concentration in the shoots and roots. The highest and the lowest increases in the shoot dry weight under non saline condition were obtained for Karaj and Alamut (23 and 6%, respectively); under saline conditions, they were found in Chamran and Kavir (66 and 3%, respectively). The results obtained from this experiment showed that the elevated carbon dioxide concentration positively influenced the growth of most cultivars. This effect was more pronounced under saline conditions, indicating that carbon dioxide enrichment could alleviate, at least in part, the negative effects of salinity. [ABSTRACT FROM AUTHOR]

The eggs and larvae of the Mediterranean flour moth, Ephestia kuehniella (Zell.) are widely used to rear parasitoids and predators for biological control programs. In this study, nutritional responses, proteolytic and digestive amylolytic activities of the fifth instar larvae as well as some biological parameters of E. kuehniella were studied on flour of nine wheat cultivars under laboratory conditions. The longest larval period of the fifth instar was on the cultivars Back cross Roshan and Sepahan and the shortest was on cultivar Tajan. The highest daily and total fecundity was observed on N-86-7. The fifth larval instar reared on Pishtaz showed the highest efficiency of conversion of ingested food. The highest general proteolytic activity was determined on the cultivar N-86-7 and the lowest was on N-80-19. Maximum and minimum digestive amylolytic activity was determined on the cultivars Kuhdasht and Khoshki line 9, respectively. According to the results obtained, Pishtaz and N-86-7 were the most suitable cultivars for laboratory rearing of E. kuehniella as the alternative host to use in the mass production of natural enemies.

The bird cherry-oat aphid, Rhopalosiphum padi (L.), is polyphagous with a nearly worldwide distribution and known as an important pest of wheat and the main vector of barley yellow dwarf virus. In this study, the possibility of antixenosis, antibiosis and tolerance of six common wheat cultivars of Chamran, Darab 2, Shiraz, Ghods, Marvdasht and Niknezhad was investigated at 2-3 leaf growth stage in the Fars province, Iran. The experiments were conducted at 24 ± 5°C, 65 ± 5% R.H. and natural light in a greenhouse, using a randomized complete design. The analysis of variance in regard to the number of adult aphids attracted to each cultivar, was indicative of significant differences among the cultivars (P < 0.01). The highest (21 ± 0.71) and the lowest (11.6 ± 0.51) mean number of adult aphids attracted per plant was observed on Shiraz and Darab 2, respectively. The antibiosis test, based on nymphs per female was significantly different among the cultivars (P < 0.01) whose average values were 62.05, 55.84, 49.89, 47.63, 42.76 and 40.65 nymphs per female on Niknezhad, Shiraz, Ghods, Marvdash, Chamran, and Darab 2, respectively. The tolerance studies based on the damage index, showed that Chamran and Darab 2, with the lowest damage index (1.33), were the most tolerant cultivars while Shiraz and Niknezhad, with the highest damage indexes of 3.00 and 3.67 respectively, were the most susceptible cultivars. The cutivars Niknezhad and Shiraz are found to be susceptible, Ghods and Marvdasht partially resistant, and Chamran and Darab 2 resistant to the bird cherry - oat aphid.