فصلنامه تحقیقات غلات
سال نهم شماره 1 (بهار 1398)

To study the effects of supplementary irrigation and nano-iron oxide on dry matter remobilization, yield and some biochemical traits of wheat under rainfed conditions, a factorial experiment was conducted based on randomized complete block design with three replications in Agricultural Research Station of Ardabil, Ardabil, Iran, in 2016. The experimental factors were included irrigation in three levels (no-irrigation checkor rainfed andsupplementary irrigation at heading and booting stages) and foliar application of nano-iron oxide in four levels (no-application as check andfoliar application of 0.3, 0.6 and 0.9 g.L-1 nano-iron oxide). The results showed that 0.9 g.L-1 nano-iron oxidefoliar application andsupplementary irrigation at booting stage increased current photosynthesis and decreased dry matter remobilization from stem and air parts.Also, foliar application of 0.9 g.L-1nano-iron oxide and supplementary irrigation at booting stage decreased hydrogen peroxide content, malondialdehyde and electrical conductivity of flag leaf, but grain yield increased about 38.43% compared to no-application of nano-iron oxide under rainfed conditions.

A factorial experiment (based on completely randomized design) with three replications was conducted in greenhouse to investigate the effect of soil Zn deficiency on the expression levels of genes encoding superoxide dismutase (SOD) and phenylalanine ammonia-lyase (PAL) antioxidant enzymes and bZIP33 transcription factor in Zn-efficient and -inefficient bread wheat cultivars.Bayat(Zn-efficient) and Hirmand (Zn-inefficient) cultivars were grown under soil Zn deficiency and normal conditions.The expression levels of three above-mentioned genes were measured using Real time PCR technique in leaf and root of the cultivars at two growth stages, one month after germination (vegetative) and 30% of heading (reproductive). The results of analysis of variance and mean comparisons of the treatments showed that the increased expression of SOD gene in vegetative and reproductive stages in Zn-efficient (Bayat) cultivar is more than that of Zn-inefficient (Hirmand) cultivar.The highest expression of PAL (50.56 fold) was observed in root of Zn-efficient (Bayat) cultivar at vegetative stage, butno significant difference was observed for PAL gene expression between Zn-efficient and -inefficient cultivars in both leaf and root tissues.The expression level of bZIP33 in the leaf of Zn-efficient cultivar (Bayat) under Zn deficiency conditions was more than that of Zn-inefficient cultivar, while no significant difference was found for the expression of this gene between Zn-efficient and in-efficient cultivars in root. Therefore, the results of this study demonstrated that SOD, PAL and bZIP33genes (probably through activation of Zn transporter genes) are involved in tolerance to soil Zn deficiency stress in Zn-efficient bread wheat cultivar.

Barnyardgrass (Echinochloa spp.) is the most important weeds in rice fields. Funguses species play important roles in biological control of the weeds, especially Echinochloain rice fields. In this research, Fusarium equiseti and Colletotrichum graminicola were isolated from E. oryzicolaandE. crus-galli and their pathogenicity effects were compared on these weeds and five rice genotypes in a completely randomized design with three replications. Two net fungi were inoculated on weeds and rice genotypes using a spore suspension consisting of 106 spore·ml-1 of distilled water. Genotype-by-pathogen biplot analysis was down for illustration of pathogenicity of two fungi (as pathogen) on host genotypes to facilitate the simultaneously visualization of relationship among pathogens and genotypes.The significant effects of pathogens were observed on disease rate and reduction of plant height, dry and fresh weight of plantlets. Biplot analysis indicated a differential interaction between pathogens and rice and Echinochloa genotypes for the studied traits. Average-tester-coordination (ATC) view of biplot indicated that Sepidroud and Binam were as the most sensitive and tolerant genotypes to two mentioned fungi according to their disease rating. The relationships view of biplot indicated there were higher positive correlations between diease rate and reduction in plantlet dry weight. Hashemi cultivar located near the biplot origin and had a horizontal resistance to fungi and can be used to biological control of barnyardgrass in the filed of this cultivar. In conclusion, the results of this study based on the severityof the disease showed thatC. graminicolafungus had more antagonistic effectsthanF. equiseti, especialy on E. crus-galli.

To study the effect of different fertilizers on reducing the effects of water deficit stress on forage maize (KSC703), an experiment was carried out as split plots in randomized complete block design with three replications in West Azerbaijan, Iran, in 2016. Irrigation treatments including irrigation at 80% field capacity (normal irrigation) and irrigation at 50% field capacity (water deficit stress) were considered as main factor and fertilizer sources including control (water spraying), organic-biofertilizer, complete fertilizers (chemical, nano) and combined application of 50% fertilizers (organic-biofertilizer + nano, organic-biofertilizer + chemical fertilizer, chemical + nano) as sub-factor. The results of mean comparisons indicated that the highest content of photosynthetic pigments (chlorophylls-a and -b) were observed under normal irrigation conditions and combined application of 50% chemical+nano fertilizers which resulted in the highest fresh (70 t.ha-1) and dry (32 t.ha-1) forage yield. This treatment combination resulted in a 47% increase in fresh and dry forage yield compared to control fertilizer treatment. The highest proline content was obtained from nano fertilizer treatment under water deficit stress conditions. Most fertilizer treatments increased leaf potassium under both irrigation conditions. Also, application of most fertilizer treatments under normal irrigation conditions increased crude protein, dry matter digestibility, water soluble carbohydrates and crude fiber content compared to the control treatment. Based on the results of this research, combined application of 50% chemical+nano fertilizers was determined as an effective fertilizer combination under both irrigation conditions due to improvement of some quantitative and qualitative characteristics of forage maize.

The effects of plastic mulch, anti-transpiration materials and irrigation regimes were evaluated on ear yield and some physiological traits of rainbow maize. The experiment was carried out in Borazjan located in Bushehr Province, Iran, during 2016 and 2017 growing seasons. The experimental design was split-split plots in randomized complete block design with three replications. The main factor of the experiment was irrigation regimes at three levels including: 1) Irrigation after 25% water depletion of field capacity (no water deficit stress), 2) Irrigation after 40% water depletion of field capacity (mild water deficit stress) and 3) Irrigation after 60% water depletion of field capacity (severe water deficit stress), sub-factor at two levels including plastic mulch and without mulch and sub-sub-factor at three levels including kaolin and atrazine anti-transpiration materials and control treatment (without anti-transpiration materials). The results showed that the interaction of irrigation regimes, plastic mulch and anti-transpiration materials was significant on ear yield. At irrigation regime of 25% water depletion, the highest ear yield (1759.8 g.m-2) was found when soil surface was covered with plastic mulch and plants were sprayed with atrazine. On the other hand, the minimum ear yield (1165.7 g.m-2) was obtained when soil surface uncovered and no anti-transpiration materials were applied. With decreasing soil water, atrazine application increased fresh ear yield more than kaolin. Under severe water deficit stress condition (60% water depletion), chlorophyll and protein contents of leaves decreased. In total, the results of this research showed that application of plastic mulch and atrazine anti-transpiration are recommended to produce the highest quantitative and qualitative yield in rainbow maize in regions where water is the main limiting factor.

Barley is one of the most important crops in the world and is also important in agricultural biotechnology as a recombinant protein production platform. In plants such as cereals, whose regeneration and transformation are difficult, in some cases transient gene expression is considered as a substitute for the stable method. Agrobacterium-based transient expression (agroinfiltration) is an inexpensive and quick way to study the function of genes and to evaluate the elements that affect gene expression (untranslated regions, introns, transcription factors and promoters). By using this method, it is possible to evaluate the function of gene constructs without time-consuming process of plant regeneration only within a few days. In order to optimize this method in barley, the effect of different treatments such as tissue type, plant age, leaves position, acetosyringone concentration, type of induction medium, time of assay after induction, Agrobacterium strain, OD of induction medium, type of procedure, duration and frequency of vacuum pump operation and barley genotype on transient expression of the ß-glucuronidase reporter gene in leaves were evaluated in this research. Also, the effect of type of induction medium, Agrobacterium strain and barley genotype on transient expression of the reporter gene in buds were evaluated. Transient gene expression of ß-glucuronidase were observed in all bud samples of Bahman cultivar and EC-82-6 genotype of barley which were inoculated with GV3301 strain harboring the reporter gene construct suspended in the induction medium with acetosyringone concentration of 200 uM by using insulin syringe. According to the results of this study, an effective and low-cost Agrobacterium-based transient expression system in barley is introduced.

Rice, as one of the most important crops, has the smallest genome among cereals and is considered as a model plant for genetic studies. The small size of this plant’s genome has led to comprehensive studies on it, resulting in a large amounts of data to be obtained. Properly collecting and storing these data and managing data from various experiments in a database for accessing researchers to them to avoid re-work and to compare their results with the results of other researchers is very important. To achieve these, bioinformatics can be great help. Therefore, the creation and development of specialized databases and the use of bioinformatics tools for data processing, efficient organization, analysis and visualization are necessary. In this paper, the major databases for studying gene expression at three levels, RNA, protein and metabolome in rice are reviewed and the characteristics of these databases for each level are discussed.