فهرست مطالب حمید تجلی

Salinity stress is a major constrain of plant growth and limiting factor of crop production in arid and semi-arid regions in the world. Wheat cultivar Barzegar is derived from the cross between an Iranian highly adapted wheat, Pishtaz cultivar and Karchia cultivar (salt tolerant cultivar from India) as female and male parents, respectively, at Seed and Plant Improvement Institute, Cereal Research Department in Karaj. Subsequent selection among segregating populations of this hybrid was done at experimental field of Yazd station. Results of yield trials and on-farm evaluations in the temperate zone showed that under salinity stress conditions (EcSoil =8-12 dsm-1 & EcWater =8-13 dsm-1), Barzegar exhibited a superior performance compared to the check cultivars Bam and Arg, and its average grain yield was 659 kg (16.5%) higher than average grain yield of check cultivars. Based on ranking method Barzegar had high stability and adaptability under saline conditions compared to the check cultivars. Under farmer's conditions trials its average grain yield was 4381 kgha-1, nearly 20% higher than average grain yield of check cultivars (3648 kgha-1). Barzegar exhibits lodging resistance and has non-shattering spikes, but has moderately resistant susceptible infection responses to rusts. However, under dry conditions of saline areas of Iran no susceptibility to these diseases is observed. Based on good agronomic performance consist of resistance to lodging and shattering, and high adaptability and stability and good quality in saline condition compared to checks (Bam, Arg and Ofogh), Barzegar released for cultivation in the saline areas (with saline water/soil) farms of temperate zone, in Iran.

Drought stress is one of the results of climate change that has a negative impact on the growth and yield of crops. Breeding for drought tolerance and production stability are important goals of crop breeding programs in arid and semi-arid regions.

In order to evaluate the stability of grain yield and drought tolerance at barley genotypes in temperate climates of Iran, 20 cultivars and barley lines, in a randomized complete block design with three replications during the two cropping years 2016-2017 and 2017-97 in four stations including Karaj, Varamin, Birjand and Yazd were evaluated under two conditions, normal irrigation and drought stress at the end of the season (irrigation interruption in 50% of heading).

Combined analysis of variance showed that the effects of genotype, year × location, location × genotype and genotype × year × location on grain yield was significant. In order to study the interactions of genotype × environment more precisely and to determine genotypes with stable and drought tolerant yield, different stability parameters and drought tolerance and susceptibility indices were calculated for each genotype. Calculation of stability parameters showed that lines 20, 4, 16 and 15 were recognized as genotypes with stable yield and suitable adaptation, respectively. In terms of drought tolerance indices in the first year, lines 4, 17, 16, 20 and 11 and in the second year, lines 7, 3, 16, 4, 20 and 5, the top genotypes were drought tolerant at the end of the season.

The use of drought tolerance and susceptibility indices, three-dimensional charts and biplot in the first and second years showed that lines 4, 16 and 20 were jointly selected as the best genotypes in terms of drought tolerance in both years, so this the results showed that these lines had good repeatability for drought tolerance. On the other hand, stability statistics also indicated the stability of yield of these lines. so due to grain yield stability, drought tolerance and high yield potential, three lines 4, 16 and 20 were superior and adaptable  lines for normal and terminal drought stress conditions in the temperate climate of Iran that after supplementary  tests can be considered to help production in these areas.

In order to investigate the agronomic characteristics of Potato under water deficit stress conditions using line-source sprinkler irrigation method and potassium fertilizer amounts an experiment was done in Khorasan Razavi Agricultural and Natural Resource Research Center during 2015-2016 as split plot design based on completely randomized blocks design. Water deficit levels at 0.75m from line-source (control), at 3.75m from line source (very light), at 6.75m from line-source (light), at 9.75m from line-source (severe deficit), at 12.75m from line source (very severe deficit) were considered as main factor and potassium levels included 0, 90, 180, and 270 kg.ha-1 K2O were as subfactor. Studied traits were included, tuber yield, percent of small, medium and big tuber yield, number of tuber per plant, average of tuber weight, plant height and stem number per plant. The results showed that water deficit stress levels had significant effects on total traits and potassium nutrition levels had same effects except percent of small and medium tuber yield and stem number per plant. Higher water deficit levels significantly decreased the tuber yield, tuber number per plant and average of tuber weight that in very severe deficit these traits reduced 92.29, 84.32, and 53.81 percent respectively. The highest tuber yield (17.92 ton.ha-1), tuber number per plant (7.94) and average of tuber weight (38.73 g) resulted in 270 kg.ha-1 K2O. The highest and lowest tuber yields were in control with 270 kg.ha-1 K2O and very severe deficit with 0 kg.ha-1 K2O.

In order to yield comparison of eight cold barley promising lines including CB-85-19,CB-85-14, CB-85-9, CB-85-15 and CB-85-10 along with three barley varieties checks(Bahman, Makoui, valfager), these experiments were conducted using RCBD withthree replications in farmer field of Torbat-e-haydaria and Fariman during 2010-2011cropping season.During the stages of growth and development, the necessary records of agriculturaland morphological traits, including the dates of spike emergence, physiologicalmaturity, plant height and 1000 seeds weight, were evaluated and after harvesting,weighing and recording the seed yield of each line, variance analysis was carried out.A randomized complete block design was performed based on the grain yield. Theresults of combining analysis showed that there were significant differences (P< 0.05)between two experimental locations for grain yield and 1000 kernels weight. Inaddition, there was a significant difference for interaction of genotype × location on1000 kernels weight. The highest grain yield (6.242 t/ha) related to CB-85-10 barleygenotype which was produced from farmer’s field in Torbat-e-haydaria and Fariman.

Salinity stress is one of the major problems for crop production. Barley is one of the best salt tolerant plants and is widely cultivated in the saline soils, but all stages of its growth as well as its grain yield are affected by salt stress. Golshan  was resulted from the cross between Nik cultivar as female parent and an Iranian landrace with 1-BC-80320 collection code, as male parent. Crossing and selection processes of this variety were carried out in experimental farm of Seed and Plant Improvement Institute (SPII), Karaj, Iran. Yield trials were performed under salinity stress in Yazd, Isfahan and Birjand research stations (EC of soil and water: 10-14 dsm-1). The result showed that Golshan with grain yield of 4392 kgha-1 had 17% higher yield performance compared to check cultivar Khatam with grain yield of 3752 kgha-1. Evaluation of salt tolerance related traits such as chlorophyll content, plant height, number of yellow leaves, root length, root weight, shoots to root ratio, biomass and potassium to sodium ratio under hydroponic controlled condition showed that Golshan had high tolerance to salinity stress. This new variety has spring growth habit and its average plant height under salinity condition was 65 cm. Golshan has semi-susceptible to susceptible reaction to the barley leaf diseases. Golshan has six-rowed spike with average of 12.3% protein content and is recommended for cultivation in the saline areas in the temperate regions of the country.

To identify bread wheat genotypes with higher grain yield and stability in saline regions of Iran, 17 elite genotypes along with three salinity tolerant control (Ofogh, Narin and Sistan) were evaluated in five regions including Birjand, Yazd, Zabol, Isfahan and Kerman, during two consecutive cropping seasons (2016-2018) under saline conditions. In all regions, the experiments were performed based on the randomized complete block with four replications. The result of combined analysis of variance indicated that the interactions of year×location×genotype were significant. To dissection of genotype-by-environment interaction (GE) and yield stability of genotypes, AMMI analysis and several parametric and non-parametric statistics were estimated. Based on AMMI2's biplot and stability statistics, G1, G2, G3, G6, G9, G10 and G20 genotypes were identified as the most stable genotypes. The results of correlation analysis showed that among all stability statistics, only ASV had a positive and significant association with grain yield. Taken together, our results revealed that G9 genotype had the highest grain yield (4.60 t. ha–1); hence, this genotype can be recommended as a high-yielding and stable genotype for cultivation in saline-prone regions of Iran.

The objective of this study was to evaluate genotypes (G), environments (E) and to analyze genotype by environment (GE) interactions on the seed yield of 20 barley promising lines by the additive main effects and multiplicative interaction(AMMI) model. The trials were conducted at two research stations (Neyshabur and Torogh Mashhad) for two successive years (2015-2017). The result’ s of AMMI analysis for seed yield indicated that the Genotype main effects, environment, and GE interactions as well as two first interaction principal components (IPCA1-2) were significant. AMMI biplot was able to distinguish stable genotypes and environments with high and low genotype discrimination ability. The genotypes 1 and 10 with higher mean yield than total mean were to be most stable genotypes, while the genotype 19 and 2 with the highest contribution to GE interaction, were to be the most instable. The result of recommended genotypes based on AMMI analysis showed that the genotypes 18, 9 and 1 were highly adapted to Mashhad and genotype 20 was adapted to Neishabour environments during this study.

The temperate climate zone has a major role in barley production in Iran. Therefore, the release of high potential varieties with proper adaptability and yield stability is one of the most important breeding objectives in this climate zone. Armaghan variety with pedigree of Legia//Rhn/Lignee 527, was derived from a cross with the aim of high yield potential and proper adaptationin in 2001-2002 that was made in Cereals Research Department in Seed and Plant Improvement Institute. In order to study the yield stability and adaptability of the elite barley lines, Armaghan and other genotypes including barley cultivar Nosrat as check were evaluated in eight locations for two years and their grain yields were compared. Results indicated that Armaghan with 8362 kgha-1had higher grain yield compared to other genotypes and check cultivar Nosrat with yield of 7857 kgha-1. Results of on-farm trials showed that Armaghan variety with a mean grain yield of 6584 kgha-1compared to check cultivar Nosrat with grain yield of 6019 kgha-1, had yield increase of 565 kgha-1(more than 9%). Armaghan variety has a spring growth habit, six-row spike, average plant height of 93 cm, and 1000 kernel weight of 44 g. This variety showed infection response of semi-resistant to semi-susceptible to powdery mildew, resistant to semi-susceptible infection response to leaf strip and infection response of 0-50MS to yellow rust.

Barley cultivar Goharan with pedigree of "Rhn-03//L.527/NK1272", was selected among barley genotypes from ICARDA and was identified as is a suitable cultivar for temperate regions under both terminal drought stress and non-stress conditions with different irrigation water management. Preliminary, advanced and elite yield trialsof this cultivar under two conditions (terminal droughtstress and non-stress) were carried out at Karaj, Birjand, Isfahan and Varamin stations. The results of the experiments showed that under non stress conditions, Goharan cultivar had a mean grain yield of 6269 kgha-1 versus 5244 kgha-1 of Rihane ( 20% increase), and under terminal drought stress had mean yield of 4720 kgha-1 versus 4035 kgha-1 of Rihane ( 17% increase). This cultivar, had a mean protein content of 12 percent which indicates its good quality. Study on status of irrigation water use productivity in some drought tolerance barley genotypes showed that cultivar Goharan had the highest amount of water use productivity among genotypes. Results of on-farm trials showed that in average Goharan had 1196 and 623 kgha-1 higher grain yield than Nosrat and Yousef cultivars, respectively under both drought stress and non-stress conditions.Based on importance of water in recent years, drought and lowering of groundwater resources, especially in arid and semi-arid regions of the country,where, there is a competition for irrigation water to cultivate spring products,cultivar Goharan was released for cultivation in non- stress areas and under drought stress in the temperate zone of the country for the sustainability of the barley production.

To study the response of barley genotypes to terminal drought stress, 20 promising barley genotypes were compared under two stress and non-stress conditions, in a split plot experiment based on randomized complete block design with three replications at the Agricultural Research Center of Southern Khorasan during 2007-2008 growing season. Drought stress levels consist of control (complete irrigation) and irrigation up to the 50% heading stage. Results showed that skipping irrigation at 50% heading stage resulted in 14.64 reduction in seed yield and 8.12 percent in biological yield compared to control condition. Spike length, plant height and flag leaf area in drought condition decreased by 12.4, 7.65 and 24 percent against complete irrigation treatment. Also, irrigation up to the 50% heading caused increasing of chlorophyll index and cell membrane permeability and declining of relative water content of flag leaf. There weren’t any significant differences among barley genotypes in terms of biological yield but the highest and lowest grain yield achieved from genotype number 18 (5997.2 kg.ha-1) and genotype number 16 (3420.8 kg.ha-1) respectively. Cultivar number 5 and 13 had the highest rate of chlorophyll index, and also number 8 had the highest relative water content (80.7%) in flag leaf. Based on the results of this study, genotypes number 18 and 20 had higher yields in both normal and drought stress conditions.

To study the effects of end season drought stress on yield, yield components and drought stress indices in barley, a split plot experiment arranged in randomized complete block design with three replications was conducted at the Agricultural Research Center of Birjand in 2008-2009 crop years. Drought stress, in 2 levels, consists of control (complete irrigation) and stopping irrigation at the 50% of heading stage, and 20 promising genotypes of barley were the treatments of the experiment. Results revealed that stopping irrigation lead to declining of 14.64 and 8.12 percent of seed and forage yields against control condition, respectively. Using stress susceptibility index (SSI) indicated that genotypes 2, 3, 7, 9, 10 and 15; using STI and GMP indices, genotypes 5, 8, 18 and 20 using MP, genotypes 8, 18 and 20, and TOL, genotypes 2, 3, 7, 9, and 10, were the most drought tolerant genotypes. Correlation between seed yield and stress evaluation indices showed that MP, GMP and STI are the best indices to be used in selection and introducing drought tolerant genotypes of barley. Considering all indices, and given that the best genotypes are those with high yield under normal condition and minimum yield reduction under drought stress, No. 18 and 20 could be introduced as the most tolerant barley genotypes to drought.