نشریه بیوتکنولوژی و بیوشیمی غلات
پیاپی 1 (بهار 1401)

Knowledge of genetic diversity in crop species can play an important role in exploiting genetic diversity and lead to the development and expansion of crop cultivation in drought-prone environments. In this regard, identifying and utilizing informative markers related to agro-physiological traits will be necessary for application in breeding programs and marker-assisted selection.

This study was performed to investigate the relationship between SCoT markers and agro-physiological traits in the durum wheat breeding germplasm. For this purpose, 220 durum wheat genotypes were evaluated for agronomic, phenological, and physiological traits. They were received from the International Center for Agricultural Research in the Dry Areas (ICARDA) and International Maize and Wheat Improvement Center (CIMMYT) during two consecutive cropping seasons (2017-18 and 2018-19). The germplasm was also genotyped using five SCoT markers. In order to identify the informative markers related to each trait, the regression analysis method was used.

According to the results, considerable variation for agro-physiological traits was observed in the studied germplasm. The majority of ICARDA germplasms that most favored by grain yield, 1000-kernel weight (TKW), normal difference vegetative index (NDVI), plant height (PH), and peduncle length (PL) well separated from the majority of CIMMYT germplasm that most favored late in the heading (DH) and maturity (DM) and higher canopy temperature (CT). These findings indicate that the breeding lines originally developed from ICARDA might possess traits of tolerance to drought conditions absent in those developed in CIMMYT. 13 SCoT loci were associated with at least three traits based on trait-marker association analysis. These markers would enhance the efficiency of parental selection in the durum wheat breeding programs. Six informative SCoT loci (SCoT16-845, SCoT16-965, SCoT33-780, SCoT24-1400, SCoT16-845, and SCoT25-680) were identified as repeatable markers that can be considered as candidate markers for assessment of other wheat germplasm collections and scanning the genome for the related traits.

This study based on phenotypic data and SCoT markers revealed a high level of diversity in durum wheat breeding germplasm that may be useful in breeding programs. This information is valuable for germplasm grouping and determination of different phenotypic and genotypic groups, developing high-yielding genotypes, and using cross-breeding programs.

Oat is one of the most important plants in the cereals family. Oat grain is used for humans and livestock, and its forage is used for livestock. Iran is located in an arid and semi-arid region. The average annual rainfall in Iran is about one-third of the world average. Therefore, drought stress in Iran is the most critical environmental stress that limits the growth and yield of crops. Nitrogen is one of the essential nutrients for crops. In the world and Iran, nitrogen is used more than other fertilizers. Nitrogen uptake by the plants from the soil is accompanied by water. Therefore, drought stress interferes with nitrogen uptake. Accordingly, the present experiment aimed to investigate the effect of drought stress after anthesis and nitrogen amounts on the physiological characteristics of three oat cultivars.

The experiment was conducted as a split-plot factorial based on randomized complete blocks design with three replications at Research Farm of Razi University during 2013-14 cropping year. Post-anthesis moisture conditions (normal and stress) were considered as the main factor and the combination of two factors including oat cultivar (Potoroo, Quoll, and Brusher) and nitrogen supply (0, 25, 50, 75, and 100% nitrogen requirement for oat) as the sub-factor. Nitrogen levels were selected based on the soil test results and the nitrogen requirements of oat in the irrigated farm without drought stress. The source of nitrogen was urea fertilizer (containing 46% nitrogen).

The results showed that the moisture and nitrogen treatments significantly affected the studied physiological traits. According to the results, the post-anthesis drought stress led to a decrease in SPAD at anthesis and grain filling stages (12.5 and 30.6%, respectively), a decrease in FV/FM at anthesis (5.3%), an increase in stomatal resistance at anthesis and grain filling stages (94 and 77%, respectively), and an increase in grain protein content (2.3%). Supply 100% of the plant nitrogen requirement compared to 0% led to improvement of SPAD at anthesis and grain filling stages (63 and 64%, respectively), an increase in FV/FM at anthesis and grain filling stages (13.2 and 13.4%, respectively), an increase in stomatal resistance at anthesis and grain filling stages (163 and 148%, respectively), an increase in chlorophyll a and b (16 and 29%, respectively), reduction of chlorophyll a/b ratio (10%), and finally an increase in grain protein content (1.5%).

The physiological traits associated with the photosynthesis of oat plants can be improved by the proper supply of moisture and nitrogen.

Durum wheat is one of the most important crops in the world. Various environmental stresses such as drought stress can affect grain yield. Drought stress is one of the most important and common causes of wheat yield decline in most parts of the world. A large part of Iran's wheat cultivated lands is located in a Mediterranean climate. In these areas, the main part of rainfall is in winter and early spring, and from mid-spring, along with reduced rainfall and ambient humidity, the air temperature also rises sharply. Drought tolerance is a slightly complex trait controlled by many genes, and it is one of the most challenging traits to study and describe. Nevertheless, existing studies on drought have shown that the drought resistance mechanism of plants is morphological, physiological, and molecular, and strategies have been developed to deal with drought stress such as mass screening, modification, marker selection, and the use of exogenous hormones. Therefore, it is necessary to find a way to grow plants with limited water in areas deprived of water.

The study was conducted to identify molecular markers associated with the studied traits using SSR markers in rain-fed and supplementary irrigation conditions. The seeds of 150 genotypes of durum wheat, including two germplasm of durum wheat of ICARDA and germplasm of durum wheat of Iran, originated from the Seed and Plant Research Improvement Institute of Karaj, were planted in two cropping years 2018-2019 and 2019-2020. The experiment was performed in an augmented design with four controls in 6 blocks in the Farm of the Agricultural and Natural Resources Campus of Razi University of Kermanshah in supplementary irrigation and rainfed sites. The traits of plant height, peduncle length, weight of main stem, spike length, number node, weight spike, number grain per spike, weight grain per spike, thousand kernel weight were selected randomly and measured in 10 plants.

Based on the results, the GWM513 marker in the supplementary irrigation environment and the marker of GWM448-1 in the rain-fed environment showed the highest correlation with the number of seeds per spike (35% and 30%, respectively). GWM153 and GWM408 markers are suggested due to the high explanation coefficient (18-35%) and the most significant relationship with yield traits as the most suitable markers to improve most of the traits related to yield in rain-fed conditions.

In the supplementary irrigation environment, a total of 24 significant markers were identified with the studied traits; among them, the number of seeds per spike had the highest amount of changes explained (30%) by the associated marker. In the rain-fed environment, a total of 21 significant associations of markers with the studied traits were identified among them; the number of seeds per spike had the highest coefficient explained (35%) by the associated marker. In the supplementary irrigation environment, 17 SSR markers significantly related to the studied traits, five markers, and in the rain-fed environment, out of 13 markers related to traits in this environment four markers participated in more than one feature.

Due to the future demand for rice, as a food required by humans, it is necessary to produce new cultivars whose yield exceeds the existing cultivars. Success in any breeding program depends on selecting appropriate genotypes as parents in the crossing program. Estimating genetic parameters such as heritability, gene effect, and the relationship between traits is fundamental to developing the most beneficial breeding method. Various mating designs such as the North Carolina I, II, and III designs are used to estimate genetic diversity and variance components. This study was performed to evaluate heterosis, genetic parameters, gene effect, and heritability of important quantitative traits in rice using the North Carolina III mating design.

In this study, two cultivars, Deylamani and Gilaneh, were used for the North Carolina III mating design according to the results of a study using microsatellite markers. After the crosses were performed, the progenies from the North Carolina III mating design were planted with their parents in a randomized complete block design with three replications. Prior to evaluation, off-type plants were removed, and then the mean of observations per plot was used for statistical analysis. SPSS and Excel softwares were used to analyze variance and estimate NCIII genetic parameters.

Estimation of additive and dominance variances indicated the presence of additive and non-additive effects in genetic control of grain yield, 100-grain weight, plant height, number of panicles per plant, number of spikelet per panicle, panicle length, and number of filled grains per panicle. Non-additive effects played an essential role in plant height, the number of panicles per plant, and the number of filled grains per panicle. The overdominance phenomenon was observed in grain yield, 100-grain weight, plant height, number of panicles per plant, number of spikelet per panicle, panicle length, and number of filled grains per panicle. In grain yield, the range of heterosis was -12.64% for the cross of F2 No. 1 × Gilaneh up to 38.5% for the cross of F2 No. 11 × Deylamani. For plant height, the highest relative heterosis based on the average parent to reduce plant height was seen at the cross of F2 No. 9 × Deylamani (-11.4%).

The results of this study indicate the existence of additive and non-additive effects in genetic control of grain yield, 100-seed weight, plant height, number of panicles per plant, number of spikelets, panicle length, and filled grain number per panicle. On the other hand, in genetic control of grain yield, 100-grain weight, number of spikelets per panicle, and panicle length, additive effects had a greater role. However, in addition to additive effects, non-additive effects were also involved in genetic control of grain yield, 100-grain weight, number of panicles, and panicle length. The study of heterosis also showed the existence of superior offspring in the studied traits and the possibility of using them in breeding programs.

Wheat has more distribution range than any crop in the word due to its wide adaptation to different climatic conditions. Occurrence of environmental stresses during wheat growth period significantly reduces its yield in most of its cultivated areas. Among different stresses, cold stress is one of the environmental factors that limiting the cultivation of wheat in the cold and the mountainous areas. Cold stress causes changes in physiological and biochemical traits in plants. This research was conduct to evaluation of some physiological and biochemical traits that related to cold tolerance in different wheat genotypes in semi cold winter region.

This study was conducted at research farm and laboratory crop physiology, Department of Plant Production and Genetics, Razi University, Kermanshah, Iran during 2013-2014 cropping cycles. The farm experiment was a Randomized Complete Block Design (RCBD) with three replications. Sowing date was mid-November. The purpose of field cultivation was to induce the normal induction of cold acclimation in different wheat cultivars under natural field conditions. In this research 12 bread wheat cultivars such as: Norstar, Zarin, Kavir, Baz, Sivand, Alvand, Pishgam, Pishtaz, Orum, Shahryar, Bahar and Parsi were evaluated. These cultivars were purposefully selected from different wheat growth types of spring, autumn and qualitative cultivars. Then, at different stages of cold acclimation, the crowns of the studied cultivars were transferred to the laboratory and in order to evaluation of physiological traits were studied under different temperatures in thermogradient freezer. To this end, a Factorial experiment based on Completely Randomized Design (CRD) with three replications was used. In this experiment, the first factor was 12 above mentioned wheat cultivars, and second treatment was five temperature treatments (+3, -3, -6, -9 and -12 ○C).

The results showed that, winter and facultative cultivars had more crown soluble proteins, membrane stability and antioxidant enzymes activity (peroxidase, superoxide dismutase and catalase) than spring cultivars. The LT50 average was -6.5 ○C. In the meantime, LT50 in winter and facultative wheat cultivars was -8.5 ○C and in spring cultivars was -4.7 ○C. The soluble proteins and catalase activity had the highest positive and significant correlation with cold tolerance.

In general, physiological and biochemical characteristics in winter and facultative cultivars (Norstar, Zarin, Orum, and Alvand) were more associated with cold tolerance than the others. In this research, Norstar cultivar with LT50= -14 ○C and Orum cultivar with LT50= -11.5 ○C were identified as resistant cultivars to cold stress.

Wheat is the most important source of protein in human nutrition, accounting for 22% of the world cultivated area. Drought stress is one of the most significant constraints to wheat production around the world. Plant growth in adverse situations can be improved by a variety of tactics, one of which is seed priming with various chemicals. Because wheat products are mostly cooked, the quality of the flour is very important. Grain protein is one of the factors that determines the quality of wheat flour. Because of the calcareous soil, lack of organic matter, and high acidity in Iran, soil application of nutrients has minimal effect on plant access to them. In such conditions, seed priming can help increase nutritional content in the wheat grain.

This experiment aimed to investigate the effect of seed priming on yield, protein percentage and concentration of some nutrients of dryland wheat grain (cultivar Azar 2). The experiment was carried out based on a randomized complete blocks design with three replications in the Research Farm of Kurdistan University during two cropping years (2018-2019 and 2019-2020). Priming treatments were included control (without priming), potassium chloride (1%), urea (2%), zinc sulfate (0.6%), calcium chloride (1.4%), vitasprin (0.1 %), cytokinin (50 mg / L) and hydroprim.

The results showed that grain yield was higher in 2018-2019 than in 2019-2020, which is likely due to the higher rainfall this year (19%). Seed priming with water led to improved grain yield in both cropping years. The highest and lowest percentages of grain protein were observed in seed priming treatment with potassium chloride and seed priming treatment with calcium chloride, respectively. Also, the highest concentration of zinc in the grain was obtained in the treatment of seed priming with zinc sulfate. Seed priming had no significant effect on the grain concentrations of potassium and phosphorus in both cropping years.

Due to the high cost of using chemical compounds for seed priming and the positive effects of hydroprim in increasing grain yield in this experiment, hydroprim can be suggested as a cost-effective way to increase yield in dryland conditions. On the other hand, with the positive effects that seed priming has on the percentage of grain protein (prime with potassium chloride) and zinc concentration (prime with zinc sulfate) in the grain, it can be used to improve grain protein, increase the quality of wheat flour, increase zinc concentration and reduce malnutrition due to zinc deficiency.

Although all cells in a plant contain the same genes and the same genetic information, only a small group of genes are expressed at any given time to coordinate cell division, growth, differentiation, development, reproduction, environmental control, and other important cell processes. And these complex tasks are performed in a coordinated way. In general, gene expression can be regulated and controlled at any of the following stages: transcription, mRNA processing, transcription stability, mRNA transfer to the cytoplasm, translation, or protein modification. A key point in regulating expression is the beginning of copying, and there is a lot of information about setting up a copying machine near where the copying begins. Studies have shown that the main components in these processes are highly conserved in yeast, animals and plants. All transgenic structures - including target genes and marker genes - require promoters to regulate replication reproducibly and predictably. Transgenes are cloned together with different types of non-institutional promoters (from other sources) or co-institutional (studied plant) during the construction of chimeric genes within transgenic vectors, thus providing biotechnologists with a wide range of expression patterns that Suitable for their research and testing. The promoter (s) used in transgenic plants are the factors that in many cases distinguish between a successful plant biotechnology project and unknown and unsuccessful projects, so careful selection is crucial in any project. This article reviews the structure of promoters in eukaryotes and plants and describes the types of plant promoters and their most significant function as much as possible.Although all cells in a plant contain the same genes and the same genetic information, only a small group of genes are expressed at any given time to coordinate cell division, growth, differentiation, development, reproduction, environmental control, and other important cell processes. And these complex tasks are performed in a coordinated way. Although all cells in a plant contain the same genes and the same genetic information, only a small group of genes are expressed at any given time to coordinate cell division, growth, differentiation, development, reproduction, environmental control, and other important cell processes. And these complex tasks are performed in a coordinated way. Although all cells in a plant contain the same genes and the same genetic information, only a small group of genes are expressed at any given time to coordinate cell division, growth, differentiation, development, reproduction, environmental control, and other important cell processes. And these complex tasks are performed in a coordinated way. In general, gene expression can be regulated and controlled at any of the following stages: transcription, mRNA processing, transcription stability, mRNA transfer to the cytoplasm, translation, or protein modification. A key point in regulating expression is the beginning of copying, and there is a lot of information about setting up a copying machine near where the copying begins. Studies have shown that the main components in these processes are highly conserved in yeast, animals and plants. All transgenic structures - including target genes and marker genes - require promoters to regulate replication reproducibly and predictably. Transgenes are cloned together with different types of non-institutional promoters (from other sources) or co-institutional (studied plant) during the construction of chimeric genes within transgenic vectors, thus providing biotechnologists with a wide range of expression patterns that Suitable for their research and testing. The promoter (s) used in transgenic plants are the factors that in many cases distinguish between a successful plant biotechnology project and unknown and unsuccessful projects, so careful selection is crucial in any project. This article reviews the structure of promoters in eukaryotes and plants and describes the types of plant promoters and their most significant function as much as possible. Although all cells in a plant contain the same genes and the same genetic information, only a small group of genes are expressed at any given time to coordinate cell division, growth, differentiation, development, reproduction, environmental control, and other important cell processes. And these complex tasks are performed in a coordinated way. Although all cells in a plant contain the same genes and the same genetic information, only a small group of genes are expressed at any given time to coordinate cell division, growth, differentiation, development, reproduction, environmental control, and other important cell processes. And these complex tasks are performed in a coordinated way.