Crop Biotechnology
Year:2019 | Volume:8 | Issue:24|Papers Count:7

Increasing of reactive oxygen species (ROS) under iron toxicity is considered as one of the major constraints to rice production. In this study the alterations of SOD, GPX1 and MDHR expression level in two genotypes of rice, Pokkali (as tolerant) and IR64 (as sensitive) were monitored under different concentrations of iron levels [(0) (nonstress)], 100, 250, 400 and 500 mg/lit-1Fe-EDTA). The treatments were done when the plants were at 4-leaf stage and lasted for two weeks. Results showed that the expression levels of genes in Pokkali were higher than IR64. The expression level of SOD in IR64, increased at iron concentration increased, while it decreased at higher Fe-level. The expression level of GPX1 was increased in IR64, but decreased in Pokkali. The expression level of MDHR in IR64 was decreased at early stage of Fe-treatment, but then increased. Inversely, in Pokkali MDHR expression reduced constantly under Fe stress. Overall, the relative over expression of genes in Pokkali and presence of different expression levels of them between different concentrations of Fe in tolerant and sensitive genotypes indicate that the gene could remarkably effect on the tolerant level of pokkali by reducing ROS production under Fe-toxicity.

Histamine, an important biogenic amine, is produced by many organisms and play a diverse role in living organisms. Many micro-organisms synthesis and stored histamine in food, especially in canned food products, posing health threat to human. Diamine oxidase or histaminase catalysis histamine in healthy individuals and reduces its harmful side effects. In this study, a full-length cDNA encoding an amine oxidase was isolated from a chickpea (Cicer arietinum) landrace (grit), deposited in Genbank database (KU058599) and cloned in a binary expression vector. The cloned cDNA had an ORF with 2013 bp length encoding a protein with 670 amino acids and a molecular mass of 75. 7 KDa. Multiple sequence alignments analysis showed that the active site and important amino acids are highly conserved in E. coli, pea and grit histaminases. Bioinformatics analysis revealed differences in 4 amino acids between grit histaminase and that of GenBank deposited Cicer arietinum amine oxidase (CAA08855). Phylogenetic analysis grouped grit histaminase (KU058599) with plant, especially legume histaminases with 99% bootstrapping.

Low temperature is an important abiotic stress limiting the production and geographical dispersion of many crops, including rapeseed, as an important oil crop. In this study, known cis-elements regulating molecular responses of plant to cold stress were used to identify genes involved in cold tolerance. From 62, 384 Unigenes from Brassica Genome Gateway, 56 cold responsive genes were identified. Promoter analysis, gene ontology enrichment, co-occurrence, protein-protein interaction and in silico gene expression analysis were performed to validate the results of gene identification. The results showed known cis-element appearance in promoter region of all identified genes which involved in different biological pathways such as Calvin cycle, respiration and signal transduction in different cell parts. Co-occurrence study of identified genes illustrated mutual connections of genes with correlations above 0. 64. Promoter analysis, PPI network and investigating transcription factors involved in transcription regulation of 56 identified genes and 98 co-expressed genes indicated the molecular mechanisms and similar pathways of plant response to cold and introduce candidate genes to be used in breeding and genetic engineering programs.

Laccases are a group of glycoproteins which can oxidize a wide range of compounds with various biological activities and industrial applications in food and beverage, pharmaceutical, textile, and even military-related industries. Regarding this enzyme structure and the ability of plant protein production machinery for protein glycosylation, a construct consisting of fungal laccaseII under control of root-specific mannopine synthase promoter and tobacco etch virus translation enhancer was designed for tobacco transformation to be used in phytoremediation. N-terminal addition of acidic tobacco endochitinase Q to Laccase directs its apoplastic secretion. Putative laccase agrobacterium-mediated transformants were confirmed using polymerase chain reaction. Semi-quantitative PCR of roots and leaves of putative transformants showed differential expression of the laccase gene at the transcriptomic level resulting from the differential function of bacterial mannopine synthase promoter. Western blotting results confirmed production of mature protein in roots which also confirms the correct function of signal peptide and secretion of this enzyme into the apoplastic space of roots. Regarding their application for protein production or phytoremediation transgenics of interest should be screened based on protein concentration and enzyme activity.

Barley (Hordeum vulgare L. ) is a model plant for genetical and physiological studies and has a high adaptability to different conditions. In order to locate QTL, the genomic areas controlling barley agronomic traits under experimental conditions were conducted in 104 families with their parents (Badia and Kavir) in the Research Farm of Gonbad-e-Kavous College in 2013-2014. Agronomic traits such as biomass, spike weight, spike number, spike length, grain yield, peduncle length, stem diameter, flag leaf length, flag leaf width, flag leaf weight, grain numbers, grain weight, and awn length for all families were measured. For the saturation of map, 19 (93 alleles), the ISSR marker used that assigned to 7 groups of attachment to 7 chromosomes with a genome length of 617. 5 cM and the average between markers equal to 5. 41 cM Morgan. A total of 21 locations with QTL were identified for the agronomic traits. Thirteen major effect QTLs that controlled a large proportion of phenotypic variation were identified. Major QTLs The effects of controlling the desired attributes and their linked markers can be used in selection programs using the marker.

In order to investigate the mechanism of tolerance to salt stress in wheat, a factorial experiment basis of completely randomized design with four replications in greenhouse media were conducted. The factors of this experiment were included salinity of sodium chloride in four levels of zero (control), 100, 200 and 300 mM and two wheat cultivars namely Niknejhad and Pishtaz as a representative of tolerant and susceptible cultivars, respectively. Leaf samples were prepared two weeks after the starting of salt stress. Then, extraction of protein from leaf tissue was done and two-dimensional electrophoresis in control plants and under salt stress plants were carried out. The results of proteome analysis revealed that 15 replicated protein spots with different expression variations were common between two tolerant and susceptible cultivars, and five protein spots of unique to each tolerant and susceptible cultivar, had significantly expression variations under stress. Protein spots were detected by mass spectrometry and the results showed that more number from commonly detected proteins were classified in functional groups including antioxidant defense and Calvin cycle, while other proteins in each cultivar had more roles in antioxidant activity. Overall, the results showed that there was a significant difference between two cultivars in terms of morpho-physiological response to salt stress, and the Niknejhad cultivar showed a better protein response under stress.

The use of the synergistic effect of nitrogen-fixing bacteria and phosphate solubilizing bacteria is one of the newest biofertilizer production strategies. Rhizosphere soil samples were collected from tomato, cucumber and bell pepper commercial greenhouses and screened for Pseudomonas and Bacillus using selective media. One hundred and eight Pseudomonas and 92 Bacillus isolates with PGP activities were isolated and characterized. Fifty-three percent of Pseudomonas isolates and 25% of Bacillus were able to grow on N free medium. Ninety-six percent of Pseudomonas isolates were able to solubilize organic phosphate and 70% of them produce IAA, while none of the Bacillus had these two abilities. About 30% of Pseudomonas and Bacillus isolates produces siderophore, although the ratio of orange halo diameter/colony diameter was greater for Pseudomonas. Only five Bacillus and 31 Pseudomonas isolates inhibited the growth of Phytophthora melonis. Based on these results, although PGP isolates of both genera were found in the rhizosphere soil of commercial greenhouses, these bacteria differed in PGP traits. A Pseudomonas isolate, P3-57 and a Bacillus isolate, C1BY-1 with 50% antagonistic activity against P. melonis which differed in PGP traits selected for future study in greenhouse conditions. Phylogenetic analyses of 16S rRNA gene sequence revealed that strains P3-57 and C1BY-1 are closely related to P. putida and B. subtilis respectively.