negin rezaei

The rapid increase in the world population and the need to increase agricultural production, and on the other hand, the rapid change of climate conditions, are the significant challenges facing the world in the coming years. Wheat, the most important plant in the cereal family, plays a vital role in the world's food security now and in the future. Therefore, producing new cultivars with high yields and carefully selecting cultivars suitable for cultivation in different climatic zones are important future research priorities.

This study investigated the reaction of different bread wheat cultivars regarding yield and its components. It also aimed to study the growing degree days (GDD) and some physiological traits related to cold tolerance in different bread wheat cultivars. This study was conducted as two independent experiments during the 2013-14 cropping year at the research field, Campus of Agriculture and Natural Resources, Razi University, Kermanshah, Iran. The first experiment was a randomized complete block design with three replications. Treatments included 12 bread wheat cultivars (Norstar, Zarin, Kavir, Baz, Sivand, Alvand, Pishgam, Pishtaz, Orum, Shahryar, Bahar, and Parsi). The second experiment was a factorial experiment in a randomized complete block design with three replications. In this experiment, 12 bread wheat cultivars were evaluated as the first factor and sampling times as the second factor in three levels: early January, early February, early March.

The results of this study showed that Sivand and Parsi spring cultivars with the highest plant growth rate in different stages of development, with 5170 and 5100 kg/ha, respectively, and Norstar winter cultivar with the lowest plant growth rate in various stages of development, with 2230 kg/ha, had the lowest value of grain yield. The correlation between grain yield, growing degree days requirement to flowering, and physiological maturity were negatively significant. Cultivars with lower grain yield had higher growing degree day’s requirements. Examination of the growing degree days requirement of cultivars up to the flowering stage showed that, on average, spring cultivars had lower growing degree day requirements than winter cultivars. The accumulation of soluble sugars in the crown of winter and intermediate cultivars during winter was higher than spring cultivars. The accumulation of soluble sugars in the wheat crown was downward during the winter, so at the beginning of winter, the crown had a higher sugar content than in the middle and late winter. Winter and intermediate cultivars, on average, had higher leaf greenness and maximum photochemical efficiency of photosystem II than spring cultivars.

According to the results obtained in the study area, on average, winter and intermediate cultivars were superior to spring cultivars in terms of physiological traits related to cold tolerance. But, due to the obtained seed yield. However, according to the grain yield obtained in this study, spring cultivars are more recommended among cultivated cultivars than the other two growth types in Kermanshah and similar climate zones.

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.

Curly top is one of the most important viral diseases of sugar beet. Use of resistance sources is a promising strategy for control of this disease. In the present study, the efficiency of four gene silencing constructs (OUT-hp، IN-hp، sense and antisense) against two major causes of curly top disease in Iran, beet curly top virus-Svr (BCTV) and beet curly top Iran virus (BCTIV), were evaluated in transgenic plants. Selection of transgenic plant seeds was carried out on selective medium 1/2MS containing glufosinate-ammonium (Basta) and the results showed that the pBCTV-IN-hp construct resulted in the highest germinated seeds. Selected plants were transferred to greenhouse and evaluated for resistance to basta and detection of silencing constructs in the transgenic plants. Afterwards, resistance of the selected transgenic plants to beet curly top viruses and resistance stability against cucumber mosaic virus (CMV) was evaluated in a completely randomized design with six treatments in a factorial experiment. The results showed that the transformed lines with each of four constructs were significantly different in severity of symptoms, plant height and number of flowering stems compared to their respective controls. Although these transgenic plants were resistant to BCTV-Svr and BCTIV, in their challenge inoculation experiments it was shown that this resistance was suppressed by CMV infection. 

Vanishing white matter disease (VWM) is considered as one of the most frequent types of inherited childhood leukoencephalopathies. Various neurological and non-neurological manifestations have been reported in this type of leukodystrophy; however, seizures are rarely described in infantile type of VWM.
To patient is a 12 months old boy who experienced frequent seizures at 4th month of age. The seizures were resistant to anti-epileptic drugs and caused 3 periods of hospitalization. Magnetic resonance imaging (MRI) demonstrated demyelinating pattern and whole exome sequencing (WES) reported homozygous mutation (c.922G > A) in EIF2B2 gene in exon 8 leading to an amino-acid substitution (p.Val308Met).
Infantile onset of vanishing white matter disease can be considered as one of few childhood leukodystrophies that are associated with early onset seizures.

In this study, big-head carp flesh was processed and fish finger was produced by the formula of 1, 2 and 3 with 70, 80 and 93.5 percent of big head fish flesh respectively. Then sensory attributes, biochemical changes and nutritional value such as peroxide value (PV), thiobarbituric acid (TBA) and the total volatile nitrogen (TVB-N) changes and microbial load of all three formulas were compared with together. According to sensory data, the formula 1 was chosen as the selected product. Quality changes were studied for evaluators’ selected formula during storage at 18˚C on the days 0, 30, 60, and 90. The results showed that fish finger prepared with formula 1, had more acceptable scores than two other formulas. The results indicated that the minimum and maximum amounts of protein belonged to the formulas 1 and 2, respectively. The amount of protein, lipid, carbohydrate and calcium of the selected product decreased during the storage and the moisture had an increasing manner. The results of the study on the changes of PV, TBA and TVB-N showed that the minimum and maximum of PV belonged to formula 3 and formula 1, and the minimum and maximum of peroxide were observed on days 30 and 60 of storage, respectively. Microbial count showed that according to increasing storage time, total count was decreased. According to the results, maximum of shelf life for the samples stored at 18˚C was 90 days.