manoochehr khodarahmi

Wheat performance is always affected by climate change and environmental stresses such as drought stress. Development of high-yielding cultivars requires genetic diversity. Awareness about heritability of traits can be helpful in determining the appropriate breeding strategy for any environmental conditions. By progeny trial after a diallel crossing, the function of genes and inheritance of quantitative traits can be estimated. This increases the ability to select parental lines, to participate in crosses, and determines the management of generations in the segregating populations.

In order to understand the genetic structure of grain yield and some morphological traits of bread wheat under normal and drought stress conditions, eight bread wheat cultivars including Star; Tirgan; Ehsan; Shirodi; Bam; Tajan, Yang and Akbari were planted in the crossing block and direct crosses were performed among the eight cultivars to produce F1 generation. This research carries out in Gorgan agricultural research station in 2020-2021 cropping season, under normal and drought stress conditions. The progenies of the crosses with their parents were evaluated based on a randomized complete block design (RCBD) with three replications. Imposing stress by terminating irrigation was initiated at the Zadoks 60 (full heading emergence) stage.

Combined analysis of variance under normal and drought stress conditions showed that the simple effects of genotype and environment were statistically significant in all traits. Also, the interaction effects of genotype×environment was statistically significant for grain yield, biological yield and 100-kernel weight. In fact, for these traits the response of genotypes was different under normal and stress conditions. Analysis of variance of Griffing's diallel method showed a statistically significant difference between genotypes in all studied traits. Therefore, among the progenies of the crosses it is possible to select superior genotypes. In biological yield and grain yield under both normal and drought stress conditions, Tirgan cultivar had the highest general combining ability, while Star cultivar showed the lowest general combining ability. Tirgan cultivar can be used to increase grain yield and biological yield under both conditions. In plant height, peduncle length and harvest index, Tajan×Yang, Ehsan×Shirodi and Bam×Yang crosses had the maximum specific combining ability, respectively. In other traits, in each condition, an individual cross had the highest specific combining ability. Under normal conditions, Tajan×Akbari cross had the highest specific combining ability in grain yield. Under drought stress conditions, Bam×Akbari cross had the highest specific combining ability in biological yield and grain yield, it simultaneously had a high specific combinability in 100-grain weight, harvest index and number of grains per spike. Therefore, Bam×Akbari cross was determined as the best cross in genetic improvement of desirable agronomic traits with high specific combining ability in yield and yield components, under drought stress conditions. The ratio of additive variance from genetic variance for plant height and peduncle length was greater than dominance variance. Subsequently, the highest narrow-sense heritability in both normal and drought stress conditions was related to plant height and peduncle length. In both normal and drought stress conditions, the highest degree of dominance was related to harvest index traits and number of grains per spike, respectively. Therefore, in these traits the lowest narrow-sense heritability, the lowest Baker's genetic ratio and the highest ratio of dominance variance from genetic variance were observed in both normal and drought stress conditions. In grain yield, a high ratio of dominance variance from genetic variance was assigned under normal (84%) and drought stress (88%) conditions, hence low narrow-sense heritability was observed under normal (8%) and drought stress (5%) conditions. In general, in grain yield, biological yield and 100-kernel weight, narrow-sense heritability was lower under drought stress conditions, compared to normal conditions, which indicates a greater ratio of non-additive effects under drought stress conditions.

The results of this study showed that under both conditions, Tirgan cultivar had the highest general combining ability in grain yield and biological yield. Tajan×Akbari and Bam×Akbari crosses were determined as the best cross in genetic improvement of desirable agronomic traits with high specific combining ability in yield and yield components, under normal and drought stress conditions, respectively. In grain yield, biological yield and 100-kernel weight, narrow-sense heritability was lower under drought stress conditions, compared to normal conditions. Based our results under both conditions in the progenies of the crosses, genetic improvement can be done in plant height and peduncle length in the initial generations, but for other traits including grain yield and its components, selection should be postponed to more advanced generations.

In order to evaluate the quantitative and qualitative performance of spring bread wheat cultivars under different planting dates, an experiment was conducted in Gonbad Agricultural Research Station, Gonbad, Golestan province, Iran, during two cropping seasons (2020-2022) as split plot based on randomized complete block design (RCBD) with four replications. Seven planting dates (1 November, 11 November, 21 November, 1 December, 11 December, 21 December and 31 December) were placed in main plots and four bread wheat genotypes (Araz, Arman, Taktaz and N-93-9) were placed in subplots. The delayed planting led to a significant decrease in the length of the phenological stages and the grain filling period. The highest grain yield was obtained from the planting at 11 November (5813 kg ha-1), which was not significantly different from grain yield in 21 November (5788 kg ha-1) and 31 November (5641 kg ha-1) planting dates. In most of the agronomic traits, the delayed planting dates (21 December and 31 December) had significantly lower values than planting in 11 November, 21 November and 1 December. Mean comparison for interaction effect of planting date×cultivar showed that planting Arman cultivar in 11 November, Araz cultivar in 11 November, 21 November and 1 December, Arman cultivar in the 21 November and Taktaz cultivar in the 21 November led to the highest grain yield. In the three delayed planting dates (11 December, 21 December and 31 December), the grain yield of Taktaz and Araz cultivars was higher than other genotypes. Mean comparisons on the traits related to bread-making quality showed that the two delayed planting dates (21 December and 31 December) had higher values in terms of protein and wet gluten content, compared to the two early planting dates (1 November and 11 November). Taktaz cultivar had the highest bread-making quality, particularly because it indicated the highest protein and wet gluten content.

Explaining the concept of the UAE, examining the foundations, and its arguments, one of the most important issues in the principle of jurisprudence, which has a special place in the fundamental headings of the principles of jurisprudence, while the widespread geography of this debate in cases where the Farrinian view is due to the UAE. The comparison and critique of their arguments in a comprehensive way in the eyes of Ferravine is not carefully explored. This study, in a descriptive-analytical way, relying on library resources and the votes of the Imamiyyah and Sunni elders, sought to answer the question of what is the argument of the UAE's preference for the Farrzin principles? The results of the present study proved that most Sunni scholars believe that some Sunni jurists have been approved. Among the jurisprudents of the Imamiyyah, although most of them are in favor of the theory of violations, many also believe in the UAE's reason, so that the result is a violation, and each group has cited some verses and narrations to prove their claim.

To determine the optimal sowing date for new bread wheat cultivars as well as to investigate the relationship between grain yield and agro-climatic indices, a field experiment was carried out as split plots layout in randomized complete block design with four replications in two cropping seasons (2020-2021 and 2021-2022) in Gorgan agricultural research station, Gorgan, Iran. Seven sowing dates (from 01 November to 31 December, with 10-day intervals) were assigned to main plots and four spring bread wheat genotypes (cv. Araz, cv. Arman, cv. Taktaz and N-93-9 promising line) were randomized in subplots. Combined analysis of variance showed that the effect of sowing date was significant on grain yield, biological yield and spike no. m-2. While there was no significant difference between cultivars for the aforementioned traits. The highest grain yield obtained from 11 November (6235 kg.ha-1) and 21 November (6105 kg.ha-1) sowing dates, respectively. In delayed sowing dates (11 December, 21 December and 31 December), grain yield of cv. Taktaz was greater than other genotypes. The three sowing dates, 01 November, 11 November and 21 November, were not significantly different for grian filling duration (42.5, 42 and 40.3 days, respectively). However, grian-filling duration significantly decreased in delayed sowing dates (33, 34.1 and 35.6 days, respectively). The highest cumulative growth degree-days (GDD) for grain filling period was calculated for sowing dates 11 November  and 21 November  (782 and 773 GDD, respectively). In conclusion, the results of this experimebt showed that the highest grian yield and maximum energy use efficiency may obtain from the sowing date window of 11 November to 21 November for Gorgan region in Iran.

In Iran, wheat is the most important agricultural product in terms of production and cultivated area, and the increase in its production has been receiving more attention day by day, and it is very important in terms of economy and food security of the people. The present study was conducted in order to investigate the relationships between different traits and to determine the most important traits affecting grain yield in bread wheat cultivars introduced in the northern climate of the country and to group them based on some morphological traits.

In this research, 20 varieties of wheat improved in the hot and humid climate of the north of the country were studied in the majority of randomized complete blocks design with three replications during three crop years of 2015-2016 at Gorgan Agricultural Research Station.

The results of combined analysis of variance showed that there was a significant difference among the studied cultivars in terms of the investigated traits. The effect of year was also significant for all traits except the number of days to anthesis, and the interaction effect of cultivar was significant for all traits except the number of tiller/m2, peduncle length and spike length, seed yield and biological yield. The highest seed yield (5.59 t ha-1) was related to Ehsan variety. Group comparison between new and old cultivars showed significant difference between the two groups in grain yield and biological yield, harvest index, 1000-seed weight, length of grain filling period and grain filling speed, number of seeds per spike, height, days to spiking and days to anthesis traits. Grain yield had the highest correlation with harvest index (r = 0.92**), seed filling speed (r=0.632**) and thousand kernel weight (r=0.595**). Three variables, length of grain filling period, number of days to maturity and spike length were entered into the regression model as the most important traits affecting grain yield, which had negative direct effects on grain yield, and the most direct effect was related to the number of days to maturity. Factor analysis identified 5 factors that explained 89.052% of the changes. Cluster analysis based on Ward method for the studied traits grouped the cultivars into four clusters. The cultivars that were in the first and second groups had higher yields, 1000 kernel weight, and seed filling speed.

According to the obtained results, among the examined traits, the harvest index had the highest correlation coefficient with grain yield, and the three traits of grain filling period, number of days to maturity, and spike length were determined as the most important traits affecting grain yield. So that the cultivars that had a shorter maturity period and the grain filling period did not interact with the stress at the end of the season, had higher grain yield. The new cultivar Ehsan, with its higher performance in three years of testing and its placement in cluster two, which had high performance, seems to be the superior variety in the climatic conditions of Gorgan.

Black or stem rust disease with fungal agent Puccinia graminis f. sp. tritici is one of the most important and destructive wheat diseases in the world, and also,in Iran. Production of resistant cultivars (use of genetic resistance) by identifying sources of resistance, transfer of their resistance genes and pyramidization of effective resistance genes in desirable wheat genotypes (Commercial cultivars and lines under introduction which are susceptible to disease but high in yield), is the most effective method of sustainable control of this disease. Previous results of seedling stage evaluation of wheat line S-83-4 were acceptable as a resistance reaction to many stem rust pathogens in the country (2014-2016). In order to study the inheritance and type of action of genes controlling resistance components including infection type and latent period in line S-83-4, this line was crossed with sensitive cultivar Avocet'S ' and base generations F1, F2 , BC1 and BC2 were produced in farm conditions. Seedlings of parents and generations were inoculated by the high virulent race TTTTF (Boroujerd region) in greenhouse and compared based on a randomized complete block design in three replications. Weight analysis of variance showed a significant difference between generations in terms of measured resistance components (infection type and latent period). The average degree of dominance was higher than one for both traits, indicating over-dominance genetic control. Epistasis interaction effects of additive × additive and dominance × dominance were significant for the both traits. For both measured traits, broad-sense heritability was estimated as moderate, while narrow-sense heritability was low indicating meaningful effct of dominance in controlling of the both studied traits. To improve the studied traits, it is ideal to apply the selection in advanced separating generations (after reaching relative purity) resulting from crossing with S-83-4 line. According to the results of segregating genes estimates, more than one gene is involved in the genetic control of the measured resistance components. According to the results of race determination, by molecular analysis of six effective resistance genes/loci of stem rust (Sr22, Sr24, Sr25, Sr26, Sr31 and Sr39) by the respective specific markers in line S-83-4, the presence of Sr31 resistance gene, confirmed.

Wheat is one of the most important crops in the world that plays a key role in ensuring food security. In wheat breeding programs, selection of genotypes with desirable agronomic traits and high yield potential have always been the goal of plant breeders. Increasing the selection efficiency for grain yield depends on genetic knowledge from morphological traits and the effect of these traits on grain yield.

In order to estimate genetic parameters and general and specific combining abilities, six bread wheat cultivars including Falat, Tajan, Bolani, Ehsan, Morvarid and Catbird were planted in a crossing block and direct and reciprocal crosses were performed among the six cultivars to produce F1 generation. The progenies of the crosses with their parents were evaluated based on randomized complete block design (RCBD) with three replications in Gorgan agricultural research station in 2020-2021 cropping season.

Analysis of variance of Griffing's diallel method showed a statistically significant difference between genotypes in all studied traits. Mean squares of general and specific combining abilities were statistically significant in most traits. Reciprocal, maternal and non-maternal effects were significant for the number of days to heading, grain yield, and biological yield. In grain yield and biological yield, Ehsan cultivar had the highest general combining ability and was identified as a suitable parent for the genetic improvement of these traits. The Catbird×Bolani hybrid had the highest specific combining ability in plant height, peduncle length, biological yield, grain yield and harvest index, it was determined as the best hybrid in genetic improvement of desirable agronomic traits with high specific combining ability in yield and yield components. The ratio of additive variance from genetic variance for plant height, number of days to heading and peduncle length was greater than dominance variance. The highest degree of dominance was related to the number of spikelets per spike, 100-seed weight, grain yield and biological yield, respectively.

The results of this study showed that in the progenies of the crosses, genetic improvement can be done in plant height, number of days to heading and peduncle length in the initial generations, but for other traits including grain yield and its components, selection should be postponed to more advanced generations.

Breeders often use generation means analysis to obtain information about inheritance, gene action, and to determine effective breeding methods to improve important agronomic traits, especially under drought stress conditions. To investigate the genetic parameters of agronomic and morphological traits in durum wheat, a field experiment was carried out using F1, F2, BC1 and BC2 generations obtained from crossing of Shotordandan variety and Dena cultivar under non-stress and terminal drought stress conditions. The experiment was carried out using randomized complete block design with three replications in research field of Islamic Azad University, Ahvaz Branch, Iran in 2016-17 cropping season. To apply terminal drought stress, from anthesis stage, the irrigation of the plots was ceased until physiological maturity. The results of weighted analysis of variance of generations revealed that there was significant differences between the generations for all measured traits except number of grain.spike-1 under non-stress conditions and number of tillers and grain weight.plant-1 in drought stress conditions. The results of generations mean analysis for spike length under non-stress conditions and plant height and spike length under stress conditions showed that the three-parameters model had the best fit. However, for other measured traits, significant chi square test (χ2) indicated the presence of non-allelic interactions in the inheritance. Additive and dominance effect played roles in controlling most of the studied traits, but the effect of dominance component was greater than the additive component. Broad and narrow sense heritability of traits under non-stress conditions varied from 11-84% and from 1-75%, respectively, and under stress conditions from 24-70% and from 1-40%, respectively. Considering the greater role of genes with non-additive effect in controlling most of traits, except plant height, spike length and 1000-grain weight, selection in durum wheat advanced breeding generations, when breeding lines are fixed and relative purity achived, is suggested.

Wheat (Triticum aestivum) is the largest food crop to cover the earth’s surface in the world. Environmental influences are considered as the measurement criteria for genetic stability.  Sensitivity of a crop genotype to the environmental factors gives rise to genotype - Environment Interaction (GEI). Breeders’ objective is to develop varieties that give high productivity under available environmental conditions.

In this study, stability and adaptation of eighteen promised bread wheat lines along with Morvaread and Gonbad as control cultivars, were evaluated in randomized complete block design with three replications at four regions in Gorgan, Gonbad, Sari and Mogan, during two cropping seasons of 2015-2017.  

Combined analysis of variance indicated significant effects of genotypes and year × location × genotype interactions. Significant interaction effects indicated different reactions of genotypes in various locations. Due to the significant effects of this interaction, genotypes × environment interaction effect was evaluated using GGE Biplot stability analysis. Results of Biplot that revealed mean and stability of genotypes, line11stayed on, in the positive direction of axis had the highest grain yield and line 2 stayed on, in the negative direction of axis had the lowest grain yield. This biplot analysis diagnosed of Mega-environment. In base of this study, among of Gorgan, Gonbad and Sari environments had strong positive correlation and genotypes had the same reactions. Mogan had next to zero correlation with three other locations and reaction of genotypes was independent. The results showed the possibility of selecting stable genotypes with high yield compared to experimental controls, which indicates genetic improvement in bread wheat breeding programs in the northern climate of the country.

Consequently, genotypes 11, 13, 7 and 8 with high grain yield and strong stability were selected.

Fungal diseases are considered as main causes of yield loss and increased costs in wheat production. Stem rust caused by Puccinia graminis f. sp. tritici (Pgt), is a devastating fungal disease of wheat, worldwide. Identification of new stem rust resistance sources, and the involved genes are required to achieve resistant cultivars and durable resistance as the most efficient control method of wheat stem rust. In order to identify new seedling resistance sources, virulence pattern of eight Pgt isolates was studied on 27 wheat commercial cultivars and elite lines of national breeding programs in a randomized block design with three replications.

Determining the exact sowing date is an appropriate tool in controlling the length of the phenological stages for optimizing the climate conditions and minimizing the effects of terminal heat and drought stresses. The agro-climatic indices are used to study of plant phenology and its relationship with grain yield. Agro-climatic indices are changed under climate change conditions. The response of crops to climatic conditions can be assessed at the plant phenological stages by monitoring these indices. The aim of this study was to investigate the grain yield of new wheat cultivars related to northern warm and humid agro-climatic zone (Iran) under different sowing dates based on agro-climatic indices in Gonbad area.

This experiment was conducted in Gonbad agricultural research station, Gonbad, Iran, during two cropping seasons (2017-2019) as split plot based on randomized complete block design (RCBD) with four replications. Five sowing dates of 1 November, 16 November, 1 December, 16 December and 31 December were placed in main plots and four spring wheat cultivars including Ehsan, Tirgan, Meraj and Kalateh were placed as subplots. In each phenological stage, agro-climatic indices were calculated which includes total day length (DL), photoperiod (PPD), growth day degree (GDD), photo-thermal unit (PTU), helio-thermal unit (HTU), hydro-thermal unit (HYTU), heat use efficiency (HUE), helio-thermal use efficiency (HTUE), photo-thermal use efficiency (PTUE) and hydro-thermal use efficiency (HYTUE).

The results showed that no significant differences were observed in grain yield of second (25 November) and third (10 December) sowing dates (5708.3 and 5626.4 kg ha-1, respectively) and their grain yield was significantly greater than other sowing dates. The grian filling period, number of spike per square meter and number of grain per spike were not significantly different in three primary sowing dates. The third sowing date had the highest values in terms of agro-climatic indices including growing degree days (GDD), day length (DL), photo-thermal units (PTU), hydro-thermal units (HYTU), during grain filling period. While, the second sowing date had maximum heat use efficiency (HUE), helio-thermal use efficiency (HTUE), photo-thermal use efficiency (PTUE) and hydro-thermal use efficiency (HYTUE). Grain yield (5269.8 kg ha-1) and number of spike per square meter (330.17) of Kalateh cultivar were significantly greater than other cultivars (Tirgan, Meraj and Ehsan).

The second and third sowing dates provided suitable conditions for plant height and resistance to lodging in different cultivars. Also, the two mentioned sowing dates were provided optimum conditions for different cultivars in terms of climatic parameters including temperature, day length, relative humidity and energy use efficiency, during grain filling period. The grain yield decreased due to severe plant lodging in the first sowing date and exposure to terminal heat and drought stresses and reduced the grain filling period duration in the fourth and fifth sowing dates. The growth period of Kalateh cultivar was shorter than other cultivars (no difference during grain filling period), which caused the plant to escape terminal heat and drought stresses, increasing energy use efficiency and consequently increasing grain yield compared to other cultivars. Therefore, Kalateh cultivar is very suitable and advisable for cultivation in low rainfall areas in northern Golestan province in the second and third sowing dates.

Wheat is one of the most important edible crops used in several food products. The success of plant breeding programs depends on the availability of parents with desired genetic diversities. In this context, we evaluated the genetic parameters in eight wheat genotypes namely Kohdashet, Morvaread, N-80-19, Darya, UR-82-17, Ehsan, Bacounoura and Atrack as well as theirs F1 progenies in term of grain yield and the relevant traits. Randomized complete block design with three replications was used. Data analysis indicated that genotypes and their F1 hybrids significantly affected grain yield, biological yield, thousand-grain weight, grains per spike, grain weight in spike, plant height, peduncle length and second internode length. The Model I of Griffing's method II was used in SAS software to determine GCA, SCA and other genetic parameters. Among parents, Ehsan cultivar exhibited the highest GCA for grain yield, thousand-grain weight, grain weight in spike, plant height and biological yield. P6×P7 cross was found to have the highest SCA effects on grain yield, thousand-grain weight and plant height. In addition, among examined characteristics, the thousand-grain weight and the peduncle length had the highest broad sense (h2= 0.98) and narrow sense heritability (H2= 0.62), respectively. These findings indicated that the distinctive crosses engaged in progenitors belongs to high×low GCA; therefore, it is inessential to set crosses with high×high GCA. As a result, potential homozygous lines can be selected from transgressive segregations to increase yield. Such crosses can be applied for exploiting heterosis.

Fusarium head blight disease caused by Fusarium graminearum is one of the most important and destructive diseases of wheat in warm and humid zone. The importance of this disease is to reduce the yield and accumulation of mycotoxin in the harvested grains from infected heads, which are dangerous to humans and animals. Production of resistant varieties with using genetic resistance sources is the most effective method of sustainable control of this disease. To study the inheritance of resistance-controlling genes in cv. Morvarid, the resistant cv. Morvarid, was done cross with susceptible cv. Falat, and generations of F1, F2, BC1 and BC2 were produced. Resistance components include the area under the disease progress curve (AUDPC), the relative area under the disease progress curve (rAUDPC) and the final severity infection (FSI), was recorded. Parents and generations were planted in a randomized complete block design with three replications. Parents and generations were inoculated at the adult plant stage by a mixture of Fusarium head blight isolats at the Gorgan Research Station. Analysis of variance showed significant differences among generations for measured traits. The average degree of dominance was approximately equal to unit (one) for all traits, indicating dominance genetic control. Epistasis interaction effects of additive × dominance, dominance × dominance were significant for the all traits. Broad-sense (0.45- 0.56) and narrow-sense (0.37-0.48) heritability was estimated as moderate, indicating the important role of additive effects and dominance in genetic control of these traits. The number of segregating genes for measured traits 1 to 7 genes was estimated. Since Morvarid Cv. is currently the most commercially resistant cultivar to Fusarium head blight, due to the additive effects of resistance genes in controlling these traits, selection can be applied to improve these traits in the early generations of this cultivar.

Stripe rust caused by Puccinia striiformis f. sp. tritici (Pst) is one of the most devastating wheat diseases worldwide. Identification of virulence factors of the pathogenas well as using resistant cultivars are effective approaches in controlling wheat strip rust. Knowledge of genetic basis of resistance to stripe rust in commercial wheat cultivars is an important objective to ensure that diverse resistance genes are deployed in breeding programs.Five bread wheat commercial cultivars were evaluated for stripe rust using 40 Pst races that were collected from different locations in Iran. Among them cultivar Aflak showed seedling resistance to all races and the other cultivars displayed field resistance at the adult plant stage. To study the heritability and genetic basis of resistance to stripe rust inbread wheat cv. Aflak, it was crossed with susceptible cultivar Avocet‘s’ and F1, F2, BC1 and BC2 generations were developed. The generations along with their parents were planted in Randomized Complete Block Design (RCBD) with three replications under greenhouse conditions. The seedlings were inoculated using the race 230E158A+, Yr27+ urediniospores. The resistance components including infection type, latent period, pustule size and pustule density were recordedon single plants of each generation. The results ofthe weighted analysis of variance showed that there were significant (p ≤ 0.01) differencesamong generations for each of the four traits. Generations mean analysis showed that in addition to additive and dominance effects, epistasis, particularly the additive × dominance epistasis also played a significant role in controlling resistance to stripe rust.For all traits, high broad-sense heritability was observed. Moderate to high narrow-sense heritability wasestimated for resistance components

Wheat stem rust caused by Puccinia graminis f. sp. tritici (Pgt) is one of the most important diseases of wheat, worldwide. New sources of resistance to stem rust could be found in synthetic hexaploid wheat (SHW) genotypes due to their high genetic diversity. In order to recognize the genetic structure of the population of the stem rust, following race analysis of 12 Pgt isolates, resistance of 348 SHW genotypes were evaluated using the infection type on a scale of 0 to 4 ratio to the four selected isolates from Gorgan and Broujerd (in 2014 and 2015) at seedling stage using randomized complete block design with two replications. Based on the reactions of differential wheat genotypes, the Pgt races TKTTF and TTTTF were identified among all isolates displaying virulence on the stem rust resistance genes Sr5, Sr6, Sr7a, Sr7b, Sr8a, Sr8b, Sr9a, Sr9b, Sr9d, Sr9e, Sr9g, Sr10, Sr12, Sr14, Sr15, Sr16, Sr17, Sr18, Sr19, Sr20, Sr21, Sr22, Sr23, Sr28, Sr30, Sr34, Sr36, Sr37, Sr38, SrTmp and SrMcN. Combined analysis of variance showed statistical significance between SHW genotypes in seedling stage in terms of their reaction to Pgt isolates. Furthermore, the significant isolate × genotype interaction suggests isolate-specific resistance in some genotypes which displays resistance to at least one Pgt isolate. Isolate-specific resistance was observed in 16% of genotypes, whereas 61 and 23% of the SHWs (such as lines 22842, 22857, 22862, 22863, 22864) were susceptible (infection type of 3-4) and resistant (infection type of 0-2) to all four Pgt isolates, respectively. Results of this research as the first report of SHWs resistant to prevalent Iranian stem rust races could be exploited in breeding programs using identified resistant genotypes which carry seedling resistance genes.

A breeding hexaploid wheat line named later Rakhshan was introduced to Iran through the CIMMYT 41th-IBWSN international nursery with pedigree of " SHARP/3/PRL/SARA//TSI/VEE#5/5/VEE/LIRA//BOW/3/BCN/4/KAUZ " in 2008. This line showed average grain yield of 9019 kg/ha compared to check cultivars Pishtaz, Shiraz, Marvdasht and Bahar average with 9060 kg/ha in Karaj, Kermanshah and Zarghan during 2008-09 crop season. This genotype showed grain yield of 8710 kg/ha compared to 7910 kg/ha of four check cultivars: Parsi, Sivand, Bahar and Pishtaz in Karaj, Zarghan, Neishabour, Isfahan and Islam Abad-Gharb during 2009-10. This line was tested in advanced and replicated trials over same 5 locations at 2010-2011 with recorded grain yield of more than 7 t/ha and measured good bread making quality. The adaptation and stability of this line was evaluated in a 2 years' experiment tested over 8 stations during 2011-13 period which recorded grain yield of 7.695 t/ha against 7.582 of Parsi and 7.547 t/ha of Sivand. During testing of this variety under on-farm and demonstrational trials in farmer fields during 2013-15 over several locations of temperate zone under normal irrigation conditions, average grain yield of 8.233 t/ha against 7.734 t/ha of Parsi cultivar was recorded. It showed also potential of 10.116 and 11.290 t/ha grain yields in Kermanshah and Alborz provinces respectively. According to the final investigations, reaction of Rakhshan to yellow rust and leaf rust was recorded as 0 to 30MS in the inoculated nurseries. In case of stem rust race Ug99 reaction was 40MR in Kenya. Bread making quality of this variety is good and it is relatively an early maturity variety.

Identifying the virulence factors of stripe rust (Puccinia striiformis f. sp. tritici) disease, awareness of numbers and identification of resistance genes in wheat breeding materials, accelerate the process of producing the resistance cultivars which are sustained against different races. To study the genetic and pathogenic and non-pathogenic spectrum of genes, five hot races of stripe rust which were collected from Mashhad, Sari, Ardabil, Moghan and Zarghan were determined using the international standard and differential genotypes and isogenic or near isogenic lines with separate race identification experiments. According to reactions, the races were­ called­ 6E158A, ­230E158A, ­6E142A, 166E150A, and 198E130A. Based on the results for the plants carrying the genes Yr2, Yr2, Yr6, Yr7, Yr7, Yr9, Yr11, Yr17, Yr18,Yr22, Yr23, Yr25 and YrA, virulence was observed in all studied races and in plants carrying genes Yr1, Yr3, Yr4, Yr5, Yr10, Yr15, Yr24, YrSP and YrCV, however, no virulence was observed against none of races. Then resistance reaction of 45 wheat genotype was separately evaluated against 5 studied races, based on a randomized complete block design with three replicates in the seedling stage. In study of the components resistance to stripe rust, latent period and infection type traits were recorded in greenhouse studies. Analysis of variance showed that there were significantly different in genotypes against pathotypes, but genotypes did not show similar reactions to different pathotypes. Probably, the YrND, YrSD, YrSU, Yr32 and Yr27 genes alone or in combination with each other, or with other unknown genes are either cause strength in genotypes with race-specific resistance caused resistance to races that were not pathogenic to these genes. The use of resistance genes in genotypes with seedling resistance is likely to be widespread in areas where similar races are common. While, the possibility of observing resistant adult plants in field conditions despite showing susceptibility under greenhouse conditions is not ruled out.

Stem and leaf rusts are the most devastating wheat diseases, worldwide. Utilization of genetic resistance and improvement of resistant cultivars are considered as the most reliable approaches to control wheat rusts. Identification of rust resistance sources and the involved resistance genes is one of the requirements for achieving sustainable resistance as well as resistant cultivars. Molecular markers have been identified for a significant number of, stem and leaf rusts resistance genes/loci. In this study, selected pre-released wheat promising lines of four Iranian major climate zones (Hot and humid, Hot and dry, moderate and Cold( were evaluated for the presence of seedling resistance genes or loci linked to the four molecular markers Sr39/Lr35, Sr31/Yr9/Lr26/Pm8/Pm17, Sr24/Lr24 and Sr22. Based on the results Sr39/Lr35 locus was identified only in line SEP59, while Sr31/Yr9/Lr26/Pm8/Pm17 locus in lines S-84-14 and SEP49. Sr24/Lr24 and Sr22 loci were not identified in all lines tested. The results of this study showed a low frequency of the resistance loci in pre-released promising lines and, thus, lines possessing these loci should be incorporated in wheat breeding programs in order to increase their frequency in new cultivars.

IntroductionDiallel crosses can be used to study the gene action and heterotic grouping and patterns. In the recent decade, use of graphical approach or GGE biplot in the investigation of genotype × environment has become more common in breeding programs. In this method, the effect of genotype and genotype and environment interaction are broken and stable cultivar selection is done basis of both effects. When GGE biplot was used for diallel data, each genotype reviled as both line and tester. Also in this case, average performance and stability of genotypes equivalent with the parent GCA and SCA respectively. Biplot method very useful tool for visual assessment and interpretation of the parent’s pattern, the environment and their interaction. The aim of this study provides the following information for wheat base graphical (1) Set parental general combining ability, (2) Estimates specific combining ability for hybrids, (3) Determine the adequate testers for future research, (4) Determine the best hybrids, (5) Determine of heterotic group and patterns among genotypes.
Materials and MethodsIn this study, seven varieties of wheat including Alamut, C-84-12, Gaspard, Ghods, Moghan 1 and Afshar (as parents) were used. These varieties with 21 genotypes of F1 generation of them base half diallel (without reciprocal crosses) in 2012-2013 crop year on research farm of Agriculture and Natural Resources, Islamic Azad University of Karaj, in drought stress condition were cultivated. A randomized complete block design with three replications was used. To analysis of variance SAS software and for Diallel analysis D2 software were used. Graphical analysis according to Yan and Hunt method done with GGE biplot software. In order to evaluate the diallel results in bread wheat, biplot method was used. In this study, 12 agronomic traits, including Grain yield, Plant height, Spike length, Spike Weight, Stem diameter length, Awn length of the second internodes, Peduncle length, Extrusion peduncle, Seed length, Seed size and 1000 Seedweight were examined.
Results and discussionAnalysis of variance showed significant differences for most of the traits. General combining ability mean squares for all the traits except plant height, length of the second internodes and stem diameter was significant. Specific combining ability mean squares for all traits except stem diameter was significant at the one percent probability level. The highest and lowest average grain yield for parents was observed for Hamoon and Afshar cultivars and for hybrids observed for crosses the Hamoon × Ghods and C-84-12 × Gaspard. The most significant positive GCA for grain yield, was reviled for Hamoon variety. The most significant SCA for grain yield per square meter, observed for Hamoon × Ghods and C-84-12 × Moghan1. For spike weight, the highest and significant SCA values observed for Afshar × C-84-12 and Alamut × Gaspard. For grain weight the highest SCA observed for Alamoot × Ghods and Afshar × C-84-12. For spike length, Alamoot × C-84-12, Ghods × C-84-12, Afshar × Gaspard and Ghods × Moghan1 had a positive and significant SCA. Based on the results of diallel analysis biplot for grain yield of the lines, Cultivars Alamut and Afshar respectively, have a highest and lowest general combining abillity. Cultivars C-84-12, Ghods, and Gaspard has a specific combining ability were higher than other lines. Cultivars were divided into two groups. The first group includes Cultivars Gaspard, C-84-12 and Hamun, second group includes Alamut, Ghods, Moghan1 and Afshar. Testers Ghods, Alamut, C-84-12 and Gaspard similarities and relationships more than other tester for grain yield. Cultivars Ghods, C-84-12 and Alamut had more discriminating effect than other varieties.
ConclusionsIn total, there were significant genetics diversity between cultivars that cause of the additive and non-additive effects in the studied traits such as yield. Comparing the results of numerical analyzes with graphical results represents the good conformity between of these two methods. Due to preferable of graphical methods in terms of faster and simpler interpretation for results, the use of these methods, to facilitate the investigation, recommended.

This study was performed for determine stability of the 18 promising barley lines and two check lines Nosrat and MB-86-5 in Six parts of the temperate zone including Karaj، Isfahan، Birjand، Varamin، Zarghan and Nishapur based on randomized complete block design)RCBD (with three replications and in two cropping seasons (2009-2011). Following combined analysis، grain yield stability assessment was performed using graphical multivariate GGE biplot analysis. Genotypes 1، 2، 16، 5 had very high yield stability. This method was reveald three mega- environments including 1. Karaj، Varamin and Zarghan، 2. Nishapur and Birjand and 3. Isfahan. Superior genotypes 2، 16 and 5 identified for these three mega-environments، Results of this study showed genotype 2 (Kavir Kavir / / Badia Badia / 3 / Torsh Torsh /cr. 279-07/ / 9cr. 279-07 / Bgs Bgs /4/ / 4 / Karoon Karoon / / Kavir Kavir) with an average yield of 6. 626 tons per ha and genotype 16 (ZBL-2640) with an average yield of 6. 438 tons per ha as stable genotypes after check genotype1 with an average yield of 6. 492 tons per ha.

In order to study the inheritance of grain yield and its components in bread wheat, two cultivars, Karchyya(drought and salinity tolerant) and Gaspard (sensitive to drought and salinity stress) were crossed.Parents together with F1, F2, F3, BC1and BC2 generations were evaluated using a randomized complete block design with three replications in 2008-2009 growing season.Grain weight per spike, number of grains per spike, 1000 grain weight, number of spikes per plant and grain yield per plant were recorded. Analysis of variance indicated significant differencesamong generationsforall traits. Mid-parent heterosis for number of grains per spike and high-parent heterosisfor rest of the traits indicated the role of dominance gene action in governing the studied characters. Furthermore, estimates of degree of dominance was in the over-dominance range for all traits. Based onthe generation mean analysis and the subsequent joint scaling test,additive-dominance model wasinsufficient for explaining the inheritance of the agronomic characters under study. Therefore, different models consisting of four to six parameterswere fitted to the generation means.Considering all traits, at least one epistaticeffect was significant in the fitted models.These results suggest the importance of non-additive gene action in controlling the grain yield and its components in the terminal water stress condition. Therefore, breeding programs utilizing this type of gene action are recommended if hybridization problems could be solved in this important crop. The broad-sense and narrow-sense heritability of the traits were estimated from 0.31 to 0.42 and from 0.10 to 0.42, respectively. The narrow-sense heritability of 1000 grain weight and number of grains per spike were higher than that of grain yield per plant. This suggests that selection for grain yield in segregating generations would not be as effective as the yield components such as 1000 grain weight and number of grains per spike.