Crop Biotechnology
Year:2018 | Volume:7 | Issue:22|Papers Count:6

Development and improvement of lentil breeding programs to deal with adverse environmental factors in comparison to other legumes has more challenges due to poor pool of genetic resources. EST-SSR (EST-Simple Sequence Repeats) markers are one of the most commonly used molecular markers in many plant breeding programs due to polymorphism in genes coding regions. Hence, in the present study, for the development of EST-SSR markers, assembly process of RNA sequences of lentil under cold stress and normal condition was used. In order to apply cold stress, lentil plants treated at 4 ° C condition. Total RNA was extracted from plant samples and was sequenced. 8905 microsatellite locations in 7211 unigene derived from lentil RNA sequences data was identified that 1293 unigene of them contained more than one SSR marker location. The most abundant type of EST-SSR marker was found to be of single nucleotide type. In this study, A/T, AG/CT and AAG/CTT motifs had the highest frequency among the one, two and three nucleotide motifs, respectively. The results of blast of unigene containing SSR showed that 80% of the unigenes had a similar record in the non-redundant protein database. The functional annotation of the unigenes showed that unigene containing SSR marker are subordinate to the critical stress-responsive terms such as binding, cell, cell parts and metabolic. Also, according to the results of this study, it can be stated that most of the identified EST-SSR markers were found in genes that play an important role in responding to cold stress, and UTR regions is often possible position. Hence, more analysis of these areas in candidate gene transcripts in response to cold stress is more important.

In order to understand of the molecular mechanisms of drought tolerance in sunflower, proteomic pattern of roots in two drought sensitive and drought-tolerant lines were evaluated under limited and favorable water conditions. After 2DE and comparison of relative abundance of protein spots using t test, 12 of 417 protein spots in sensitive and 17 of 467 in tolerant line were affected by drought stress significantly. Following nano-LC MS/MS the protein spots were identified using Mascot search engine in NCBI protein database considering more than 10 % sequence coverage and score of above 80. Cytoplasmic and nuclear proteins were the most proteins which were affected by water deficiency. Three protein spots i. e. Enolase, Glyceraldehyde 3-phosphate dehydrogenase and Chalcone synthase were expressed differentially in these lines. Reduction of Enolase as a sign of metabolic impairment could be resulted in downstream process under drought stress. Increased expression of Glyceraldehyde 3-phosphate dehydrogenase and Chalcone synthase could have a role in detoxification/removal of oxidative destruction and antioxidant capability of the tolerant line. Increased level of heat shock protein, dihydroflavonol reductase, Seed linoleate 9S-lipoxygenase, Ubiquitin carboxyl-terminal hydrolase and G protein indicated crucial role of defensive, protective and transductive process in reduction of drought injuries.

Acidic soils are a serious threat to the production of crops throughout the world. In order to study the alleles associated with soil acidity tolerance in barley plant, and also accomplish effective haplotype groups, phenotypic testing in pots containing acidic soil and in the form of Augment with 96 genotypes and 4 controls, and 27 traits were evaluated on plants. To investigate the allelic and haplotypic diversity, the genotypes were identified by 7 microsatellite markers related to soil acidity tolerance. Analysis of allelic variation showed that the highest pic and Gene Diversity were 3. 429, 0. 441 and 0. 490 respectively, which belonged to the HvMATE-21indel marker, and the Cit7 marker had the lowest value. Also, the results of the haplotype study showed 41 haplotype groups. The group 16, which included genotype 6, had the highest yield and soil acidity resistance with a yield of 2. 017 gr / plant. association analysis between molecular and phenotypic data suggested that among 20 effective alleles on the evaluated traits, the Do-D allele had the greatest impact on yield and its components with effect on 3 traits, number of seeds per spike, number of Fertile spike and yield (in plant). Do-B was also R2 equal to 39. 5 for the number of spikes per plant of the highest R2 among the alleles involved in yields and yield components. The markers associated with tolerant haplotypes and tolerant genotypes in this study can be used in research and breeding programs.

Many plants adapted to cold climates flower only after an extended period of cold, namely vernalization. In the lifetime of a winter cereals, flowering due to vernalization is not only an essential part of the reproductive process but also a critical developmental stage that can be protect the plant against environmental stresses. This process in cereals such as winter wheat is mainly regulated by the VERNALIZATION genes, VRN1 and VRN2. Although many studies on vernalization in wheat have been reported, the molecular mechanism of vernalization is still largely unknown. Recent studies were shown that a class of small non-coding RNAs, microRNAs (miRNAs), plays a key role in flowering by integrating into the known flowering pathways. In the present study, we investigated the expression of miR319 and its target gene (MYB transcription factor) under the vernalization treatments in spring and winter wheat cultivars. Our results demonstrate that cold treatment induced the miR319 expression in both cultivars, but miR319 level is down-regulated in Norstar and up-regulated in the spring wheat cultivar Baz. Likewise, the expression levels of MYB3 gene was decreased in both cultivars exposed to vernalization. There was reverse relationship between expression of miR319 and its target gene MYB3. These results highlight the complex interactions between genotypes, miRNA and expression of target gene under different vernalization treatment.

Potato virus S (PVS) of the genus Carlavirus belongs to the Betaflexiviridae family is one of the important potato infectious viruses. To detect PVS, the suspected leaf samples were collected from potato fields in Ardabil province during summer in 2015 and 2016. To assess the biological properties, symptomatic leaves inoculated to indicator plants in the greenhouse condition. The samples were tested for PVS infection using DAS-ELISA. RT-PCR for molecular detection was done using specific primers related to the coat protein area of Potato virus S. The coat protein gene nucleotide sequences of two isolates of Potato virus S called Ag-9 and Os-11 obtained from Agria and Oceana cultivars were determined. The CP sequences of two isolates were compared with each other and with 29 other isolates of the virus. The reconstructed phylogenetic tree clustered the isolates in two main groups I (subgroups IA and IB) and II. Two Ag-9-PVS-F and Os-11-PVS-F isolates were clustered in IB subgroup along with isolates from Azarbaijan, Hamedan, Kerman and Esfahan as well as isolates from Hungary, Ukraine, Scotland and India. The putative coat protein amino acid sequence alignment of this two isolates with 6 Iranian and 5 foreigner isolates showed difference in 8 and 25 amino acids for Ag-9-PVS-F and Os-11-PVS-F isolates respectively. The results indicate that there are various PVS isolates in the country, and the difference in nucleotide and amino acid sequences may indicate differences in the geographic origin and hence the type and timing of entry of virus isolates into the region.

Transient expression is widely used as an alternative method for stable transformation of plants, especially cereals, trees and recalcitrants. In this method, multiple copies of transgene are introduced in to the plant cell and then are transcribed and translated. As introduced gene is not integrated in the genome, its expression is not affected by epigenetic factors and the location of insertion. Transient expression is a convenient method for functional analysis of genes including overexpression, silencing, gene expression networks, protein localization, promoter analysis, identification of biosynthesis pathways and so on. Additionally, this method is applied in biotechnological industries like production of recombinant proteins. Transient transformation is performed by different methods, however, many of them have overlap. So, a combination of these methods can be used for transient expression. In this review, various transient transformation techniques, their advantages and disadvantages, latest progress regarding transient expression in model and crop plants and potential and limitations regarding the application of transient expression technique in science and industry will be discussed.