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The nitrogen regulatory policy (NRP) solution is introduced as a mitigation measure against environmental nitrogen losses and keeps food production in the Safe Operating Space of the Nitrogen Planetary Boundary. Meanwhile, scientific research shows that steps taken to reduce environmental harm can increase the unpredictability of calorie production from crops. This study sought to investigate the impact of NRP solutions on the level of risk of accessibility to calorie sources from domestic production, the variations in calorie sources by livestock and non‐livestock diet components, and the responses of different dietary preferences, namely, poor, medium, and rich livestock protein diets, against NRP solutions in the Zayandeh‐Rud River basin, Iran. We developed the aggregate household food security index (AHFSI) and combined it with outputs of crop simulation model to examine how changes in dietary energy supplies under three NRP scenarios—low, moderate, and high nitrogen fertilizer application—affect the stability of three regional dietary preferences. The comparison of NRP scenarios movements realized that increases (or decreases) in nitrogen fertilizer rates contradicted the stability in AHFSI. Additionally, a one‐unit change in the average calories from non‐livestock sources, such as wheat and potatoes, results in greater fluctuations in the standard deviations of produced calories compared to changes in meat and dairy production. We proposed that in order to prevent adverse effects of NRP solutions on food security, mitigation strategies addressing the NRP solution should be structured based on (i) regional heterogeneities, (ii) type of crops, that is, food and feed crops, (iii) the range of nitrogen rates movement; (iv) and the socioeconomic background related to dietary preferences or economic deciles of food expenditure. [ABSTRACT FROM AUTHOR]

One of the most devastating foliar diseases of wheat worldwide is Septoria leaf blotch (STB), caused by Mycosphaerella graminicola (asexual stage/Anamorph: Septoria tritici) which has been recently intensified in some regions in Iran. In this study, 49 wheat genotypes and 20 wheat differential genotypes were evaluated for their reaction to infection by six isolates of M. graminicola collected from infected fields during 2016–2017 at seedling stage under greenhouse conditions. According to the analysis of variance (ANOVA) of leaf pycnidia coverage percentage, a significant difference (p <.01) was observed between M. graminicola isolates and wheat cultivars. The interaction between genotypes and isolates was also significant (p <.01) and the results indicated a specific interaction between genotypes and isolates. The results presented Dezful and West Azerbaijan isolates that were the most virulent with more pathogenesis on differential genotypes. Although 47 of the wheat genotypes were susceptible to all isolates, some genotypes, including Wc‐46,224 (Austria), Wc‐45,425 (Portugal), Wc‐45,565 (Turkey), P.S.No4 (Italy), Dehdasht, M3 Synthetic, KavKaz‐k4500, Arina, Flame, and Riband were resistant to all isolates. In addition, the isolates exhibited different virulence patterns on wheat genotypes. The results of this study revealed high virulence of M. graminicola isolates, and Iranian and foreign wheat genotypes, commonly used in the region, presented high susceptibility, and the resistance sources had been identified among genotypes that can be applied in the wheat breeding programs. [ABSTRACT FROM AUTHOR]

Fifteen million tons of bread is annually produced in Iran of which the 80% of share in production belongs to traditional bakeries. The present study examines the aspects of the energetic, economic, and environmental impacts of production of Iranian breads (Barbari, Lavash, and Sangak). The results showed that energy demand of a typical baking process of Iranian breads is 22.93–26.08 MJ kg−1. The annual energy utilization of these bakeries is 239.57 TJ, accompanied with 13,308 ton year−1 of CO2 emissions. Sangak bread production had the highest energy efficiency, energy productivity, and the lowest rejected energy. In terms of economic aspects, the highest net income, profit to cost, and economic productivity, were related to Barbari bread production. Sangak bread production had the least environmental impacts. Lavash bread production, although it is the thinnest bread, had the highest energy consumption, was responsible for emitting the largest share of Greenhouse Gas (GHG) to the atmosphere and it had the lowest economic return. The flour was the most influential input on the energy efficiency, cost, and GHG emissions among the three examined types of bread production. Therefore, improving wheat cultivars and flour production process, may reduce the energy consumption and the GHG emissions in the bread industry. [ABSTRACT FROM AUTHOR]

Wheat streak mosaic tritimovirus (WSMV) seriously damages wheat worldwide. We report analyses of new complete ORF (CO) sequences from seven Australian isolates with 56 COs and 128 coat protein (CP) genes sequenced previously. Eleven CO and three CP sequences were recombinants so were removed from our analyses. Patristic distances of maximum‐likelihood phylogenies of nonrecombinant (n‐rec) CO sequences and their CP sequences were closely correlated (R = 0.994, p ≤ 0.00001). The phylogeny of all 188 n‐rec CP genes had four well‐supported phylogroups (I–IV): phylogroup I (one Mexican sequence), phylogroup II (six Iranian sequences), phylogroup III (48 sequences) and phylogroup IV (133 sequences), each with basal Iranian sequences and either mostly European (phylogroup III) or mostly American (phylogroup IV) terminal sequences. Australian and South American sequences formed a phylogroup IV subcluster within a Pacific Northwest USA cluster. Unlike the Iranian, South American and European populations, the North American and Australian populations demonstrated recent population imbalance. Sample collection dates of 40 CO sequences are known, allowing WSMV phylogeny dating by RTDT methodology. The most recent WSMV ancestor was dated at 1456 CE, and the Australian cluster at 1998.7 CE, only 2–3 years before WSMV was first reported. Tritimoviruses originated in central Eurasia, WSMV first entering wheat in its Middle East domestication centre and one basal lineage being taken to Mexico after the Spanish conquest, whereas the other most basal lineage spread throughout Iran, before spreading to other world regions. Probable future spread to other world regions of additional WSMV phylogroups, and of interphylogroup recombinants, constitutes a biosecurity concern. [ABSTRACT FROM AUTHOR]

The centre of origin of the globally distributed wheat pathogen Parastagonospora nodorum has remained uncertain because only a small number of isolates from the Fertile Crescent were included in earlier population genetic and phylogeographic studies. We isolated and genetically analysed 193 P. nodorum strains from three naturally infected wheat fields distributed across Iran using 11 neutral microsatellite loci. Compared to previous studies that included populations from North America, Europe, Africa, Australia, and China, the populations from Iran had the highest genetic diversity globally and also exhibited greater population structure over smaller spatial scales, patterns typically associated with the centre of origin of a species. Genes encoding the necrotrophic effectors SnToxA, SnTox1, and SnTox3 were found at a high frequency in the Iranian population. By sequencing 96 randomly chosen Iranian strains, we detected new alleles for all three effector genes. Analysis of allele diversity showed that all three effector genes had higher diversity in Iran than in any population included in previous studies, with Iran acting as a hub for the effector diversity that was found in other global populations. Taken together, these findings support the hypothesis that P. nodorum originated either within or nearby the Fertile Crescent with a genome that already encoded all three necrotrophic effectors during its emergence as a pathogen on wheat. Our findings also suggest that P. nodorum was the original source of the ToxA genes discovered in the wheat pathogens Phaeosphaeria avenaria f. sp. tritici 1, Pyrenophora tritici‐repentis, and Bipolaris sorokiniana. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Puccinia triticina (Pt), the causal agent of leaf rust evolves through forming new pathotypes that adversely affect the growth and yield of wheat cultivars. Therefore, continued production of resistant varieties through exploring novel sources of resistance in wild relatives which are abundantly found in Iran and the neighbouring regions is a major task in wheat breeding programs. The aim of the present study was to explore 60 wild wheat genotypes selected from the species Triticum monococcum, Aegilops tauschii, Ae. neglecta, Ae. cylindrica, Ae. triuncialis, Ae. umbellulata, Ae. speltoides, Ae. columnaris, Ae. crassa and Ae. ventricosa for resistance to leaf rust. The cultivar 'Boolani' and Thatcher near‐isogenic lines were used as controls. Two‐week‐old seedlings were inoculated using 10 Pt pathotypes, and the infection types were recorded. The genotypes were also analysed for polymorphism using six sequence‐tagged sites (STS) and sequence characterized amplified region (SCAR) markers. Forty‐eight genotypes produced high infection types (3+) for two pathotypes, but the remaining genotypes produced low infection types of '0; =' to '1+CN' to all pathotypes. The latter included three accessions of Ae. tauschii, two accessions of each Ae. umbellulata, Ae. columnaris and Triticum monococcum, and one accession from each Ae. triuncialis, Ae. ventricosa and Ae. neglecta. Analysis for STS and SCAR markers suggested several genotypes could carry the genes Lr9, Lr10, Lr19, Lr24, Lr26 and Lr37 or their potential orthologs in addition to unknown resistance genes. In conclusion, the identified resistant genotypes could be further characterized and used in wheat breeding programs for leaf rust resistance. [ABSTRACT FROM AUTHOR]

The aim of the present trial was to examine the effects of wheat germ (WG) consumption on metabolic control and oxidative stress status of type 2 diabetes mellitus (T2DM) patients. Eighty participants with T2DM were randomly allocated to receive 20-g WG (n = 40) or placebo (n = 40) in a randomized double-blind clinical trial for 12 weeks. Serum lipid profiles, glycaemic indices, total antioxidant capacity, and malondialdhyde (MDA) were assessed. A total of 75 subjects completed the trial. Compared with the placebo, WG consumption led to significant reduction in total cholesterol (TC) concentrations (p = .04). There was a trend regarding TC to high density lipoprotein ratio (p = .08) following 12 weeks WG consumption, although they were not statistically significant after correcting for multiple testing. In addition, within-group comparison revealed a significant rise in total antioxidant capacity concentration (p = .001) in WG group. We observed no significant effects of WG intake on glycaemic status, blood pressure, MDA, triglyceride, and low density lipoprotein levels. WG consumption for 12 weeks could decrease serum TC levels and had no significant effects on other metabolic variables and MDA in patients with T2DM. Though observed health benefit effects were small, it might lead to a major impact on wider public health. [ABSTRACT FROM AUTHOR]

This study assessed the growth of wheat under climate change conditions (increases in CO2 and temperature) in southwestern Iran. Future climate data were projected using long‐term climate data for radiation and minimum and maximum temperatures for the baseline period 1980–2010. The future climate scenarios made use of delta changes from the Coupled Model Intercomparison Project Phase 5 (CMIP5) in the R package of the Agricultural Model Intercomparison and Improvement Project for 2040–2070. After generating the weather data, the Agricultural Production System Simulator wheat model was applied to assess the potential impact of climate change on wheat yield and the relative growth rate, crop growth rate, total dry weight and leaf area index. Averaged across all locations, an increase of 1.6 and 2.3°C in annual temperature was projected under representative concentration pathway 4.5 (RCP4.5) and RCP8.5, respectively. The decrease in the average length of the growing season was 7.5 and 9.3% under RCP4.5 and RCP8.5, respectively, in the mid‐21st century with respect to baseline. The mean cumulative radiation will decrease by 11.6 and 14.3% averaged across all sites for RCP4.5 and RCP8.5, respectively. Grain yield will decrease at all sites for both RCPs. The greatest decrease in wheat yield was projected for Izeh under RCP4.5 and RCP8.5 (7.9 and 9.3%, respectively) for 2040–2070 relative to baseline. A greater grain yield at baseline than for the RCP8.5 and RCP4.5 scenarios was closely related to higher leaf area index, relative growth rate and crop growth rate values during the reproductive phase. Thus, these parameters can be defined as indicators of crop yield. [ABSTRACT FROM AUTHOR]

Copyright of Irrigation & Drainage is the property of Wiley-Blackwell and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Projecting agricultural crop, such as bread wheat, yield under future climate plays a vital role in planning for supply and demand, especially in developing countries. The objective of this study was to investigate impacts of climate change on grain yield of rainfed wheat in the Kashafrood basin situated in northeastern Iran. Climate projections of two General Circulation Models (HadCM3 and CGCM2) under two climate change scenarios (A2 and B2) were employed in this study. A statistical downscaling method was employed for developing the quantitative relationship between large-scale atmospheric variables (predictors) and local variables (observations), also daily climatological parameters performed by the LARS-WG5 stochastic weather generator, the Decision Support System for Agrotechnology Transfer (DSSAT) Version 4.5 adjusted to evaluate rainfed wheat performance. Results of this study represented substantial difference between GCM models and scenarios for wheat yield in the study area. The A2 scenario indicated more negative impact on wheat yield than the B2 using both GCM models. Highest increase and decrease of grain yield in comparison with the baseline belongs to the 2010-2039 period (+15%) using the HadCM3 model under the B2 scenario and the HadCM3 model under A2 in the 2040-2069 period (−50%), respectively. In general, growth period length indicated a markedly decreasing trend in both periods. There were strong relations between wheat yield and precipitation rate and growth period length in this study. Copyright © 2011 Royal Meteorological Society [ABSTRACT FROM AUTHOR]

Phalaris minor (littleseed canary grass) is a major weed in wheat fields in some parts of Iran. Diclofop-methyl, fenoxaprop-P-ethyl, and clodinafop-propargyl are three acetyl coenzyme A carboxylase (ACCase)-inhibiting herbicides that are commonly used to control this grass in wheat fields. Thirty-four P. minor populations with suspected resistance to ACCase-inhibiting herbicides were sampled from wheat fields in the provinces of Fars and Golestan in Iran. The dose-response assays that were conducted under controlled greenhouse conditions indicated that 14 populations were resistant to fenoxaprop-P-ethyl, seven populations were resistant to both fenoxaprop-P-ethyl and diclofop-methyl, and three populations were resistant to fenoxaprop-P-ethyl, diclofop-methyl, and clodinafop-propargyl. These populations showed different levels of resistance to the applied herbicides, compared to the susceptible population. These results suggest that different mechanisms of resistance could be involved. The enzyme assay revealed that the existence of modified ACCase in the three most-resistant populations (AR, MR4, and SR3) is responsible for the resistance of these populations. [ABSTRACT FROM AUTHOR]

To provide insight into the genetic structure of Mycosphaerella graminicola populations in Iran, a total of 221 isolates were collected from naturally infected wheat fields of five major wheat-growing provinces and analysed using AFLP markers and mating-type loci. All populations showed intermediate to high genotypic diversity. In the Golestan and Ardabil populations two mating types were found at near-equal frequencies, whilst all populations were in gametic disequilibrium. Moreover, clonal haplotypes were identified in different sampling sites within a field in both the Khuzestan and Fars provinces, demonstrating that pycnidia are probably the primary source of inoculum. All five populations had low levels of gene diversity and had private bands. Low levels of gene flow and high genetic differentiation were observed among populations and different clustering methods revealed five genetically distinct groups in accordance with the sampling areas. The Golestan and East Azarbaijan populations were more genetically differentiated than the others. Random genetic drift, selection and geographic barriers may account for the differentiation of the populations. The results of this study indicate a population structure of M. graminicola in Iran contrasting to that of most other countries studied. [ABSTRACT FROM AUTHOR]

Field experiments were conducted at five locations in the major wheat production regions of Iran to evaluate the efficacy of sulfosulfuron in controlling weed barley species (including Hordeum spontaneum, Hordeum murinum, Hordeum distichon, and Hordeum vulgare) in the 2004–2005 and 2005–2006 growing seasons. Sulfosulfuron was applied either postemergence (POST) or preplant-incorporated (PPI) at 0, 20.25, 30.75, 40.5, 51.0, 60.75 or 71.25 g ai ha−1 to plots arranged in a randomized complete block design with four replications. Sulfosulfuron at the recommended rate (20.25 g ai ha−1) failed to provide acceptable control of the weed barley species. However, the level of control increased with the application rate, particularly at rates >51.0 g ai ha−1. Generally, PPI-applied sulfosulfuron resulted in markedly greater control levels than those of a POST application and complete control of H. murinum and H. vulgare was achieved with PPI-applied sulfosulfuron at all rates >20.25 and 30.75 g ai ha−1, respectively. In most cases, the wheat yield increased with the application rate without any crop injury. The highest yield increase (186%) was obtained with a PPI application of 71.25 g ai ha−1. [ABSTRACT FROM AUTHOR]

Rye infestations have increased in frequency and severity in the wheat fields of Iran and have caused yield reductions in wheat production. In order to study the competition effects of wheat against rye, an experiment was conducted at the research centers of Karaj and Varamin, Iran, during 2001 and 2002. The experimental design was a randomized complete block with 24 treatments and four replications. The treatments included pure stands of wheat at densities of 350, 450, 550, and 650 plants m−2 and volunteer rye densities of 10, 30, 50, and 70 plants m−2, and mixed stands of wheat and rye at complete factorial densities. The results indicated that rye was a superior competitor compared to wheat. The biological and economic yields of wheat were mainly affected by interspecific competition in the Karaj region. This was also true during the first year in the Varamin region but, in the second year, the biological and economic yields of wheat were equally affected by interspecific and intraspecific competition because of increasing precipitation. The evaluation of competitive ability, using regression coefficients, showed that in Karaj, the effect of one rye plant on wheat was approximately equivalent to three and two plants of wheat in reducing the grain yield of wheat in the first and second years, respectively, while in Varamin, it was equivalent to three and 1.2 plants of wheat, respectively. In other words, each 0.36 and 0.51 rye plant in Karaj and each 0.36 and 0.84 rye plant in Varamin had the same impact on the reciprocal wheat grain yield as did one wheat plant in the first and second years, respectively. [ABSTRACT FROM AUTHOR]

This article reports on an analysis of technical efficiency and environment-technology gaps in wheat farming in Iran. A random sample of 676 farmers was selected from the province of Kerman in 2004. In this study, Kerman is divided into five regions based on climatic and geographical conditions. The province is situated in the south-eastern part of Iran and contains substantial variations in climate. The technical efficiency indices are computed using three approaches. First, a standard stochastic production frontier was employed using pooled cross-sectional data. Secondly, regional stochastic frontier production functions were estimated. Lastly, the metafrontier approach was used because production environments and technologies are expected to differ between the five regions. Use of this method enabled technical efficiency scores to be corrected by the coefficient of the environment-technology gap ratio (ETGR). Estimates of the frontier were obtained assuming a translog functional form. Results indicate that farms differ in technical efficiencies, ETGRs and the use they make of inputs. Mean ETGRs vary substantially between farms and across regions whereas mean technical efficiencies are reasonably similar across regions but differ in the extent of variation among farms within each region. A low ETGR for the north-western region is attributable to a lack of water resources, restricting the ability of farmers to benefit from improved varieties, and small-sized farms, which militate against mechanization embodying labor-saving technologies. The results do not lead to definitive policy prescriptions. But they do provide indicators of where farm-level research is likely to be most effective in closing the environment-technology gap, for example by enabling farmers to take greater advantage of the productivity-enhancing effects of improved technologies embodied in cropping machinery and irrigation facilities. The ability of farmers to alleviate the environmental constraints on wheat production is likely to vary across regions, and will depend on the nature of these constraints and the ability of researchers to design technologies suited to each region that will overcome them. [ABSTRACT FROM AUTHOR]

Field and greenhouse experiments were conducted in 2004 and 2005 to study weed control and the response of winter wheat to tank mixtures of 2,4-D plus MCPA with clodinafop propargyl. The field experiments were conducted at Yazd and Oroumieh, Iran, with factorial combinations of 2,4-D plus MCPA at 0, 975, and 1300 g ai ha−1 and with clodinafop propargyl at 0, 64, 80, 96, and 112 g ai ha−1 in four replications. The greenhouse experiments further evaluated the effect of these tank mixtures on weed control, where each herbicide mixture was considered as one treatment and the experiment was established in a randomized complete block design with four replications. In the field experiments, the herbicides were applied at wheat tillering, while in the greenhouse experiments they were applied at the beginning of the tillering stage and at the four-leaf stage of the grass and broadleaf weeds, respectively. The results indicated antagonistic effects between 2,4-D plus MCPA and clodinafop propargyl. The best tank mixture with regard to weed control efficacy was 2,4-D plus MCPA at 975 g ai ha−1 with clodinafop propargyl at 96 g ai ha−1. The wheat grain yield was also increased by the tank mixture of clodinafop propargyl with 2,4-D plus MCPA. Generally, to inhibit clodinafop propargyl efficacy reduction due to tank-mixing with 2,4-D plus MCPA, it is recommended that the application dose of 64 g ai ha−1 should be increased to 96 g ai ha−1. [ABSTRACT FROM AUTHOR]

This article presents a research regarding the herbicide risk assessment during the Wheat Self-sufficiency Project in Iran from 1994 to 2004. A risk index, the environmental impact quotation, was employed to estimate the environmental impacts of herbicides applied to wheat agroecosystems. The result reveals that the overall risk posed by the herbicides applied to wheat agroecosystems increased considerably, as evidenced by a 71 percent increase in herbicide usage and a 62.2 percent increase in environmental impact rating.

This article discusses cadmium phytoremediation by rotating sunflower and wheat in high salinity soils in Iran. According to the authors, the use of sunflowers and wheat instead of the usual rotation of cotton and wheat significantly reduced the levels of cadmium in wheat shoots and wheat grain while the cadmium was concentrated in the sunflower shoots. They concluded that sunflower and wheat rotations could significantly reduce cadmium transfer to the food chain in Iran because wheat bread is a major dietary component for the Iranian people.

An experiment was conducted to determine true and apparent ileal amino-acid digestibility of a native cultivar of wheat (Mahdavi), autoclaved wheat (120°C for 30 min) and spaghetti by-products available in Iran. One hundred 21-day-old broiler chickens were fed a standard corn–soybean meal starter diet from day 0 to 28 post hatch. At 28 days 80 chicks were distributed according to possessing very nearly the same average bodyweight to 20 wire cages. The experimental units were allocated at random to five dietary treatments with four replicates per treatment. The basal diet contained corn and soybean meal as the major ingredients. Three test diets were formulated containing wheat, autoclaved wheat and spaghetti by-products as the sole source of dietary protein and each test diet was combined with a basal diet 50:50 on a weight basis to form three assay diets. The apparent and true digestibility of amino acid in the test ingredients were estimated from those in the assay diets basal/test diet mixtures, using the difference method. The apparent and true amino-acid digestibility of the test ingredients were significantly different ( P < 0.01). Autoclaving of wheat increase its amino-acid digestibility ( P < 0.01). Among the test ingredients, the average ileal amino-acid digestibility of spaghetti by-products was higher than wheat and autoclaved wheat but it was lower than values for the basal diet ( P < 0.01). [ABSTRACT FROM AUTHOR]

The Russian wheat aphid (RWA), Diuraphis noxia (Mordvilko), poses a serious threat to wheat (Triticum aestivum L.) production in many parts of the world. This research was initiated to evaluate wheat accessions for detection of resistance to the RWA. Over 12,000 wheat cultivars and plant introductions (PIs) from the USDA-ARS National Small Grains Collection were evaluated for reaction to RWA feeding damage. Twenty-nine PIs from Iran, Afghanistan, and the former Soviet Union, of various agronomic backgrounds were identified as having moderate to high levels of RWA resistance. This information is useful to wheat breeders searching for sources of resistance to the RWA to incorporate into their breeding programmes. [ABSTRACT FROM AUTHOR]

Barley yellow striate mosaic virus (BYSMV) was identified in Iran by electron microscopy and serology. The virus was widespread in the Fars province causing mosaic, stunting and head sterility in wheat and mosaic symptoms in Setaria spp. In 1989, about 1/3 of wheat plants in the Bajgah Experiment Station, 15 km north of Shiraz, were infected. The yield in individual plants was drastically affected. Rhabdovirus particles were consistently observed in leaf-dip preparations and thin sections from the infected plants. The virus was transmitted by Laodelphax stritellus to wheat. It reacted with BYSMV antisera from Italy and Morocco but not with antisera to several other rhabdoviruses of gramineous plants. [ABSTRACT FROM AUTHOR]