فهرست مطالب ایرج لک زاده

The analyses of genotype × environment interaction in multi-environment yield trials are very important for evaluation, selection and recommendation of crop varieties. The purpose of this study was to identify high yielding and stable barley lines for introduction in different regions of warm climates of the Iran.

17 barley promising lines (with two checks Auxin and WB-94-3) will be evaluated in two years (2017 – 2019) using RCBD with three replications in five stations of warm zone including Ahvaz, Darab, Zabol, Gonbad and Moghan.

The results of variance analysis showed that the effects of location, genotype and genotype × location, genotype × year and genotype × year × location interactions were significant at the 0.01 probability level. The polygon-view of GGE biplot led to the identification of four superior lines (G18, G10, G19, and G17), six poor lines and three mega-environments. Among the test locations, Gonbad had a high discriminating ability to show differences between the genotypes and Moghan showed the least of discriminating; Also, Gonbad showed the highest amount of broad sense heritability of grain yield (0.780) and Moghan showed the lowest amount of broad sense heritability of grain yield (0.018).

Comparison of the studied lines with the ideal genotype showed that lines G18, G10, G19 and G17 were the closest lines to the ideal genotype with high yield and relative yield stability. Finally, these four lines were selected as the top lines for additional studies.

Evaluation of genotypes under multiple environments is the prerequisite for the development of stable and superior genotypes for sustainable barley production in different environmental conditions. In order to evaluate the yield stability and determine the portion of different morpho-phonologic traits in the interaction of genotype × environment in promising barley lines, 17 barley promising lines with three checks including Nimrooze/Sahra and Auxin cultivars and WB-94-3 line) were evaluated in two years (2017 – 2019) using RCBD with three replications in five stations of warm zone including Ahvaz, Darab, Zabol, Gonbad and Moghan. Stability analysis was performed using different nonparametric methods. The results of the nonparametric methods were integrated using selction index of ideal genotype (SIIG). The morpho-phonologic data were analyzed by path analysis model which is composed of a main effect and four multiplicative effects. The flowering time (X1), maturity time (X2), plant height (X3), and 1000-kernel weight (X4) were assumed to be sequential characters to justify grain yield productivity (Y) in barley. The results of analysis of variance of grain yield using parametric and non-parametric methods showed that the effect of genotype, environment and genotype × environment interaction was significant at the level of 1% probability. The results showed that based on the nonparametric methods (SIIG index), lines no. G10, G18, G19, G16 and G15 were stable lines and higher than average grain yield. The positive correlation of SIIG with genotypic components of flowering time (V1) and 1000-kernal weight (V4) indicated that the 1000-kernal weight and flowering time are the main contributor towards GE interaction for grain yield in warm zone barley.

To determine the yield stability of barley promising lines, 17 lines along with three control genotypes were evaluated in five warm zone stations during two years (2017-2019) in randomized complete block design with three replications and their stability was determined using AMMI (additive main effects and multiplicative interaction) and SHMM (Shifted multiplicative model). Analysis of variance of grain yield using AMMI model showed that the effect of genotype, environment and genotype × environment interaction was significant at 1% probability level. Genotype × environment interaction analysis based on AMMI model showed that the four main components of interaction were significant at the level of 1% probability. These four components explained 84.7% of the changes in genotype × environment interaction. The lowest value of RMS PD was related to AMMI1 model. Therefore, the interpretation of the results using the AMMI1 model is more valid than the AMMI2 model. According to the AMMI2 model, lines WB-96-8 and WB-96-9 had specific adaptability with the Zabol region and line WB-96-12 had specific adaptability with Moghan. Lines WB-96-10, WB-96-17, WB-96-18 and WB-96-19 were the high-performance lines in this study. The grouping of locations based on the SHMM model created two groups. The first group includes Darab, Ahvaz and Zabol, which are part of the warm zone stations in the south of the country. The second group included Moghan and Gonbad stations (warm northern zone).

The main purpose of this research was to identify barley promising lines with high grain yield and yield stability for warm region of Iran. In this experiment, 17 barley promising lines and two check cultivars were evaluated in five agricultural research stations; Ahvaz, Darab, Zabol, Gonbad and Moghan, Iran, in 2015-16 and 2016-17 cropping seasons, using randomized complete block design with three replications. Combined analysis of variance showed significant effect of year, year × location and year × location × genotype on grain yield. To identify genotypes with high grain yield and yield satbilty, Lin and Binchr('39')s superiority statistic and GGE biplot analysis method were employed. The lowest values of Lin and Binchr('39')s superiority statistic were for lines No. 2, 3 and 9. GGE biplot analysis revealed that the first and second principle components explained 40% and 24% of total variation, respectively. In this experiment, two mega- environments were identified. The first mega-environment included Ahavaz and Darab, and the second mega-environment included Zabol, Gonbad and Moghan. Considering grain yield and yield stability stability estimates, line NO. 2 has been identified with wide adpatation and released for warm regions (north and south) and line NO. 3 with specific adaptaion for the north warm region of Iran.

To identify barley promising lines with high and stable grain yield for warm regions of Iran, 17 barley lines as well as three check cultivars; Zahak (in South) or Sahra (in North), Nimrooz and WB-93-3 line were evaluated using randomized complete block design with three replications in five agricultural research field stations of Ahvaz, Darab, Zabol, Gonbad and Moghan, Iran, for two cropping seasons (2016-17 and 2017-18). Combined analysis of variance showed significant effects of genotype, year × location, genotype × location, genotype × year and year × location × genotype on grain yield. For identifying genotypes with high and stable grain yields, mean rank, rank standard deviation, non-parametric statistics; Si1, Si2, Si3, Si6, NPi1, NPi2, NPi3, NPi4, and parametric statistics; coefficient of variance, Shukla’s stability variance, Wricke’s ecovalence, Kang’s rank-sum and AMMI analysis methods were used. According to the results, lines no. 3 (Dasht//Ebc(a)/Badia/3/Sahra) and line no. 4 (Dasht//Ebc(a)/Badia/3/Nik) in the southern warm and dry regions, and line no. 9 (Violeta/Mja//Manal/Alanda-01) in northern warm and humid regions of Iran were identified as superior lines which can be released as new commercial cultivars, and also be used as parents in the national barley breeding programs.

Management of irrigation networks can play a very important role in the hardware and software performance of these networks. In this research, by conducting field studies on suspended sediment transport and conveyance efficiency, the effect of operating conditions on sedimentation and water losses at Khouzestan province irrigation networks was analyzed. The inflow-outflow method and sediment flux continuity equation were used to determine the canal losses and sedimentation of suspended load in the studied reaches, respectively. The investigation was done on 4, 21 and 16 reaches of the main, secondary and tertiary channels, respectively. The ratio of free board of flow in canal as operation index was computed. The effects of this index on sedimentation rate and water losses relative to input discharge were studied in each kilometer of the canal. Results showed that 10% decreasing in the operational discharge relative to the designed discharge caused 0.23 and 0.26 kg s-1 km-1 increasing in sedimentation rates of the main and secondary channels, respectively. As the distance from the upstream of the main channel increased, the channel efficiency decreased. So that the increasing rate of the water losses in main channel of Karkheh irrigation network was 0.12 percent of the entrance discharge in each kilometer distance from the beginning of the channel. The increasing rate of water losses for the western and eastern channel of Dez irrigation network were 0.16% and 0.09%, respectively.

Tolerance to the disease is defined as the plant's ability to reduce damage caused by a pathogen attack and yield is good even when the plant is infected by pathogen. The concept of tolerance arises from the fact that in conditions of severe disease infection, in some cultivars, yield reduction is less than the other cultivars. In this study, the tolerance of 20 wheat cultivars was evaluated against yellow rust. The effect of stripe rust in Neishabour on grain yield under conditions of severe disease (stress) and protected from disease (non- stress) were analysed. The mean reduction (%) in grain yield in all cultivars infected by yellow rust was 18.2%. Damage by stripe rust varied from 3.5 to 57 percent. Based on the results of two years of disease stress, Kavir, Neishabour and Inia (with 16%, 14% and 13% yield loss, respectively) were more tolerant to yellow rust. In moderately susceptible cultivars, Tajan with 5.71% yield reduction was identifiect as the most tolerant cultivar. Sirvan among the cultivars with moderate infection (5MS) had highest resistance reaction. The average yield reduction of Sirvan in disease condition was about 15%, and its 1000 grain weight reduced by 9% as compared with protected condition.

Tolerance to diseases is, the plant's ability to produce good yield even when the plant is infected by pathogen. In fact tolerant plants are susceptible to the pathogen but not destroyed by pathogens and generally little damage is caused on the plant. In this study, the tolerance of 20 wheat genotypes was evaluated against leaf rust. The effect of leaf rust on yield was evaluated in severe disease (stress) conditions and in protected from disease conditions (the controls) in Ahvaz area. The mean percentage of yield reduction caused by leaf rust was 25.2% over all genotypes. The range of yield loss was varied from 7 to 46 percent. The lowest yield loss due to the leaf rust, ranged from 6 to 16% in Shirodei, Aflak, Sirvan, Shiraz, Inia and Ofogh cultivars indicating their highest yield stability to leaf rust. Based on these data, the highest yield loss ranged from 30 to 50% in Bolany, Neyshabur, Toos, Alvand, Roshan, Star, Shahriar and Veerynak cultivars with the lowest yield stability. The cultivars Kavir, Shahriar, Roshan, Toos, Veerynak, Bahar, Bolany, Alvand and Ofogh were susceptible to leaf rust. Ofogh and Bahar with 16.52% and 21.8% yield loss respectively, were the most tolerant cultivars of this group.

Triticale is a hybrid cereal derived from crossing wheat with rye. In areas where soil and water were as limiting factors for plant growth, the silage of triticale can be used as a substitute for corn silage. This study was conducted to evaluate the effect of microbial additives on the morphological characteristics, chemical composition and gas test of triticale silage, in a completely randomized design with 3 treatments and 5 replications. The treatments were included of triticale silage without bacterial inoculation (control), triticale silage inoculated with Lactobacillus plantarum and triticale silage inoculated with Enterococcus faecium, Lactobacillus brevis and Lactobacillus plantarum. Dry matter, crude protein, pH, gas test, ammonia nitrogen, total nitrogen, effluent and sensory test of silages were determined. The average of dry matter, crude protein, total nitrogen, the amount of effluent, morphological characteristics, the amount of gas production at the time of 96 hour and the parameters of gas production (B,C) showed no significant differences in all treatments (P>0.05). Also, the average of pH of silages which microbial additives were used in the preparation of them, were significantly lower than the control group (P

For assessment of genotype × environment (G × E) interaction effects and determination of the most sustainable genotypes 20 barely lines were analyzed in at eight different experimental field stations. The experiments were performed based on Randomized Complete Block Design (RCBD) with three replicates. Grain yield was obtained and the results of the combined analysis of variance revealed genotype, environment and genotype × environment interaction effects were highly significant. Genotypes yield means showed that the G1, G13 and G4 genotypes had the highest grain yield. AMMI model analysis was used to determine the magnitude and significance of the genotype × environments interactions and divided G×E interaction to two principle components that explained 46/48% and 19/52% of interaction effects respectively and residuals. Based on biplot and AMMI analysis G, G genotypes were selected as candidate's lines with both best performance and grain yield sustainability. The environment E5 with high IPCA 1 and low IPCA 2 had the highest effect on determination of genotypes. The genotype G20 was selected as candidate line with high grain yield performance and stability.

This expriment was carried out to evalute the effect of changing in sink- source relationship and grain yield of some wheat genotypes by path analyses. The exprimental arrangment was split plot in RCB design with three replication conducted in research field of agricultural and natural resources research of Khouzestan. Main plot were consists of six spring wheat genotypes and sub plot included flag leaf remove, flag leaf remove + spike covering, spike covering and control.  Significant differences were found between genotypes and treatments of grain yield, number of spike/m2 and number of spikelet per spike at 1% stataistics level. The interaction effect was significant for grain yield, biological yield, harvest index, 1000 grain weight, number of grain per spike, number of grain per m2, number of spike per m2 and number of spikelet per spike at 1% stataistics level.it should be noted that results showed the high genetic diversity existed among wheat genotypes and the number of grain per m2 was the most effective and most important trait that influenced the grain yield.

Terminal heat stress is the most widespread heat stress in the world. In order to evaluate the effect of heat stress on yield, yield component, and mopho-phenological traits of barley, 10 barley genotypes including the 2-row genotypes: Mahour, Khoram, Nimrooz, Abidar and 6-row genotypes: Yousef, Rihan 03, Izeh, Zahak, Nosrat, Jonoub were tested under normal (optimum sowing date) and heat stress (late sowing date) conditions in experimental field of Shahid Chamran University of Ahvaz. The experiment in each condition was arranged in a randomized complete block design. Terminal heat stress caused significant reduction in days from sowing to heading (38%), days from sowing to maturity (34%), plant height (47%), peduncle length (36%), biological yield (52%), spike length without awn (21%), number of spikelet per spike (31%), number of kernels per spike (36%), 1000 kernel weight (7%), harvest index (7%) and grain yield (42%). According to the results, in normal condition Yousef with 5.4 t/ha and in stress condition Rihan 03 and Jonoub with 3.4 t/ha have the maximum grain yield. Abider in both conditions showed the minimum yield. Based on the results, the maximum correlation coefficient was observed between harvest index and grain yield in both conditions, heat stress (r=0.77, p ≤0.01) and normal (r=0.91, p ≤0.01), suggesting the considerable role of this trait for evaluating the barley genotypes in heat stress experiments. 6-row barley genotype had superiority for most of traits in compare to 2-row genotypes and finally gave more grain yield in both conditions.

In order to determine the optimum planting date under deficit output area، this research was carried-out in 2010-11 and 2011-12 cropping seasons، in split-plot arrangement، using complete randomized block design with three replications in Khuzestan Agriculture and Natural Resource Research Center. Main and sub plots were consisted of four planting dates (Oct. 27 with 10 days interval) and four superior lines، respectively. Results showed that effect of year was significant for days to heading and physiological maturity، biological yield، grain yield، grain number per spike and grain growth rate. The interaction effect of planting date × genotype was significant only for harvest index. The effect of planting date was significant for spike per unit area. Genotypes difference were significant for days to heading، harvest index، thousand grain weight، spike per unit area، grain number per spike and grain growth period. The highest grain yield with 6268 Kg/ha was obtained in the second planting date. Except grain filling rate، correlations of grain yield were positively significant with all other traits. Grain yield decreased in response to planting delay، mainly due to the reduction of grain filling period. According to the polynomial equation of grain yield trend، Nov. 17 determined as the optimum planting point.

Many barley cultivars especially hull-less genotypes are susceptible to covered smut caused by Ustilago hordei (Pers.) Lagerh. Artificial inoculation of disease for resistance evaluation is also difficult and common methods of artificial inoculation are inefficient. The present study was conducted for three years to evaluate resistance of 27 hulled and hull-less barley advanced lines and cultivars to covered smut with three inoculation methods. A factorial experiment based on complete randomized block design with three replications was performed for two years. Three inoculation methods including inoculation only in field by spore spraying, inoculation only in laboratory by spore suspension and inoculation in field + laboratory, together with a non-inoculated treatment (check) were considered as the first factor and barley genotypes as the second factor. Number and percentage of infected heads were recorded at harvest time. Based on the results, inoculation in field + inoculation in laboratory was the most effective method for artificial infection of covered smut followed by inoculation only in laboratory. Inoculation only in field did not lead to induction of sufficient infection. Therefore, considering the easy application, inoculation only in laboratory can be recommended as the most practical method for artificial inoculation of the diseases. In this study line MOLA/SHYRI//ARUPO*2/JET/3/…. Was assessed as the highly resistant and cultivar Jonob as the highly susceptible genotypes.

In order to study the effects of different levels of water logging at different growth stages on yield and yield components of barley WB-79-10, a field experiment was carried out using split plot in randomized complete block design with four replications in Ramin Research Field Station in a growing season (2009-2010) in Ramin Agriculture and Natural Resources University, Ahvaz. Tillering, stem elongation and booting stage were assigned to main plots, and water logging periods, including 0, 7 and 14 days in terms of water logging were randomized in sub–plots. The results showed that between the beginning stages of water logging and various water logging periods for yield and yield components, significant differences exist. The water logging at tillering stage had more damage than stem elongation and booting stages on grain yield and its components. In the tillering stage, grain yield at 7 and 14 days, compared to control water logging 42 and 78.28 percent respectively, to the spikelet, respectively 20.84 and 37.5 percent and to the grain number per ear 22.31 and 41.04 percent respectively, decreased. Overall, the results showed that water logging at each stage of plant growth, even in a short period, led to irrecoverable damage on yield and its components on the leaves.

Line WB73-6 (Trompillo، CMB74A-432-25B-1Y-IB-1Y-OB) was first introduced in Iran through a nursery received from CIMMYT in 1989. It was selected in a preliminary experiment in Zabol research station among the genotypes of IBON in 1990. In other preliminary and advanced yield trails carried out in Zabol and other stations in southern provinces of Iran with warm climate in 1991-1997، line WB73-6 produced higher grain yield than other advanced lines and check cultivars and showed also good adaptability and yield stability. The global mean grain yield of this line in these experiments was 4902 kgha-1، which was 404 kgha-1 higher than that of the check cultivars. The most specifications of this line are geneal compatibility، high tolerance to loding and diseases، moderate tolerance to grain loss، tolerance to axis breaking، tolerance to drough and high temperature in late growth stages، high 1000 kw (42 g) and high seed protein contents (12%). In on-farm trials carried out in three locations in Zabol and two locations in Khuzestan province during 1999 and 2003 cropping seasons، its grain yield was 350-580 kgha-1 higher than the yield of check cultivars. This line was officially registered in Iran by the National Cultivar Release Committee of Agricultural، Education and Extension Organization with the name of Nimrooz in 2009.

In order to study wheat genotype responces to different waterlogging stress levels during stem elongation stage and evaluation of indices of tolerance and sensitivity to tension, an experiment was conducted as a split – plot based on rondomized complete blocks design (RCBD) in three replications, in 2007-2008 growing season at Ahvaz Agricultural Research and Natural Resources Center. In this study, the wheat genotypes (Chamran, Virinak, S-78-11, S-80-18) were plucked into primary plot and the waterlogging levels (0, 10, 20 days) were placed into secondary plot. Six indices of tolerance and sensitivity to waterlogging stress (MP, GMP, STI, TOL, HARM, SSI) were calculated for yield. In normal conditions, the line S-80-18 with yield 4/99 tons h-1, and in mild and severe conditions, the line S-78-11 with the yield 3/68 tons h-1 had the highest yield. The indices of MP, GMP, HARM, STI which had the highest correlation with the yield in normal conditions and also had different stress level were introduced as superior indices. These indices characterized the lines S-78-11 and S-80-18 as tolerant genotypes and the Virinak cultivar as sensitive to waterlogging. On the other hand, the indices of TOL and SSI also showed the line S-78-11 as the most tolerant and Chamran cultivar as the most sensitive to genotypes compored to waterlogging stress.

In order to study of the grain yield and its components in spring wheat genotypes affected by resources limitation under optimum condition, an experiment was conducted using split plot experiment in RCBD design with three replications in Agricultural and Natural Resources Research Center of Khouzestan-Iran in 2010-2011 cropping season. In this study, main plot were consists of six wheat spring genotypes and flag leaf removal, flag leaf removal + spike cover, spike covering and control were considered as sub plot. Results of analysis variance showed that difference of treatments and genotypes was significant for grain yield and number of spike/m2 at 1% level, Also interaction effect was significant for grain yield, harvest index, biomass, 1000- grain weight, number of grain/spike and number of spike/m2 at 1% level. Control treatment with 4113 (kg/ha-1) and also No. 4 genotype with 3970 (kg/ha-1) had the highest of grain yield. Result showed that with application of cultural management, cultivation of this genotype will be very successful in the region.