JOURNAL OF AGRICULTURAL BIOTECHNOLOGY
Year:2016 | Volume:8 | Issue:3|Papers Count:8

Bone morphogenetic protein receptor-1B is one of the major genes significantly affect ewe ovulation rate. The aim of this study was to screen exon 8 of BMPR1B in single- and twin-birth ewes of Iranian Lori-Bakhtyari, Shal, Ghezel, and Afshari breeds. DNA was extracted from blood of ewes and rams from numerous sheep flocks and the genotype patterns were screened by PCR-SSCP approach. Results of SSCP analysis showed that there are three genotypic patterns in the four above-mentioned breeds. The highest abundant pattern and the lowest pattern were pattern 1 (73 %) and pattern 2 (8 %), respectively, in the whole flocks.There was a significant difference between these three genotypic patterns in terms of litter size attribute, so that ewes harboring Pattern 2 had the highest litter size average (1.7 lamb per parturition) while ewes carrying Pattern 3 had the lowest litter size average (1.4 lamb per parturition). Furthermore, the PCR amplicon from exon 8, containing these genotypic patterns, were sequenced. The sequencing results of candidate samples from different classes of SSCP showed that there were four new mutations in BMPR1B of Iranian sheep. Three of these mutations were nucleotide conversions, including G812T, T854A, and C855A mutations which caused to tryptophan to lysine (W219L), phenyl alanine to tyrosine (F233Y), and phenyl alanine to lysine (F233L) conversions, respectively. More importantly a C nucleotide insertion mutation corresponding to 855 nt of BMPR1B CDs was also observed which can cause to producing a stop codon at 266 amino acid position and consequently a dysfunctional polypeptide. In conclusion, these results clearly indicate the presence of important mutation in BMPR1B in Iranian sheep breeds which can significantly affect ewe fecundity attributes.

Salinity stress is one of the most important environmental stresses affecting pistachio trees and causes decrease its production. In this experiment the effect of salinity stress on protein expression pattern, the content of proline and antioxidant enzymes (catalase, gayacol peroxidase, ascorbate peroxidase and superoxide dismutase) were carried out on two pistachio rootstocks including of Badami-Sefid and Badiami-Zarand. The experiment was performed as factorial based on Completely Randomized Design in a controlled greenhouse condition with three treatments and 20 replications. In this research, three salinity treatments were used include control (distilled water), moderate stress (60 mM NaCl) and severe stress (120 mM NaCl). After appearing the salt stress symptoms (decrease of vegetative growth and leaf area), protein pattern and some morphological and biochemical characteristics were determined.Results showed that protein expression pattern, vegetative growth and biochemical characteristics were affected by salinity treatments and responses of the two rootstocks were completely different. Under salinity stress, Badami-Sefid rootstock exhibited more protein bands reduction and elimination compared to Badami-Zarand. Results also showed that vegetative growth and total chlorophyll content in Badami-Sefid rootstock were decreased more than Badami-Zarand under salinity stress. Also, it has been found that by increasing salinity levels, proline content and antioxidant enzyme activities were higher in Badami-Zarand compared to Badami-Sefid. It seems that Badami-Zarand rootstock has more ability to keep leaf proteins and therefore, higher resistance to salinity stress.

Functional genomics helps to understand the key mechanisms involved in salt stresstoleranceandallows the possibility of targeted genetic manipulation to improve crop tolerance tosalinity . The goal of this study was to identify new genes related to salt stress and functional analysis based on expressed sequence tags (EST). Therefore, two EST libraries under control and salt stressed conditions were downloaded from Harvard and Graingenes databanks. EGassembler, NCBI BLAST, MaxPlanck and IDEG6 software tools were applied for clustering and assembling EST sequences, determination of proteins related to unigenes (contigs and singletons), functional categories and statistics test, respectively. Results showed that twenty functional categories are significantly different between control and stress conditions. Most of contigs and singletons fell into protein and RNA categories whereas CHO metabolism and TCA and organic transformation had the minimum of numbers of contigs and singletons in both control and salt stressed conditions. Percentage of unigenes in mitochondrial electron transport/ATP synthesis, Lipid metabolism, redox, protein, RNA, DNA, and cell categories were significantly higher in stress condition compared with control condition. Therefore, these functional categories could be involved in the mechanism ofresponse to salt stress. Two hundred and seventy-one genes were differentially expressed that grouped into 23 functional categories. The wheat genes identified in this study can be considered as candidates genes to improve salt tolerance through genetic manipulation.

Milk Thistle (Silybum marianum L.) is one of the important ancient medicinal plants that have been used to treat liver disease, bile-related diseases and poisoned individuals by poisonous mushrooms. Assessment of genetic variation in Milk Thistle like the other important plants is a key component in breeding programs. The aim of this study was studying genetic variation of some Iranian Milk Thistle ecotypes using ISSR marker. A total of 41 repeatable polymorphic marker loci were produced by 9 ISSR primers. The average of polymorphism information content (PIC), Shannon’s information index and Nei’s gene diversity were 0.38, 0.49 and 0.33, respectively. Using cluster analysis by UPGMA algorithm and Jaccard similarity matrix, different ecotypes of Milk thistle grouped in 4 main clusters. We did not find an exact match between dendrogram grouping and geographical grouping of ecotypes. This could be due to the high diversity of this plant or relocation of ecotypes. The results indicate existence of a significant variation among Iranian Milk thistle ecotypes to start the breeding programs.

Genetic maps with high density and wide genome coverage play significant role in basic and applied genetic researches. In recent decades, with the advent of DNA markers, the huge development has been created in genetic map preparation and saturation in various plant species. In this study, IRAP, REMAP and ISSR markers were applied to saturate the genetic map of barley in a population with 149 double haploid individuals derived from a cross of Clipper and Sahara. The basic genetic map of this population was used as a frame for further analysis. In general, among the 120 primers used, 6 IRAP, 7 REMAP and 3 ISSR primers showed polymorphism between parents which generated 11 IRAP, 7 REMAP and 4 ISSR markers. Eighteen markers segregated in population, out of which 12 markers assigned to 7 barley linkage groups. Two markers deviated from the ratio of 1: 1. The maximum number of markers was assigned to linkage group 2. In the current investigation, retrotransposon-based markers were able to saturate the gaps of barley genetic map on linkage groups 1, 3, 5 and 6. The results showed that retrotransposon markers can be effectively used for saturation of barley genetic maps.

Patterns in heritable molecular data can be used to summarize the relationships between populations of a species. In Iran, camels are providers of milk, meat and fibers. Using of 81 reproductive individuals belonging to five sampling locations ofCamelus dromedarius in Kerman province, eight microsatellite markers3T (3T YWLL08, VOLP03, VOLP08, YWLL38, CVR01, YWLL44, VOLP32 and VOLP673T) 3T were analyzed to genetic structure and genetic distance in these populations. DNA extraction was conducted with optimized and modified salting-out method. The polymerase chain reactions for 81 individuals were successfully done with all primers and then amplification products were resolved on 8% polyacrylamid gel and stained with silver nitrate. The highest genetic distance obtained between Shahr-e Babak and Sahra-e Jahad (0.56) populations and the lowest genetic distance was observed between the two populations of Rafsanjan (0.11). Principal component analysis indicated that all samples could be mainly regrouped into three main clusters and most suitable number of genetic groups in dataset was explained. Results of this study indicated that in the first level of clustering, Shahr-e Babak, Rafsanjan1 and Rafsanjan 2 populations shared the same cluster and Shamshir Abad had another separate cluster while Sahra-e Jahad population appeared as an independent cluster. A similarity of geographical distribution was in good accordance with founded genetic relationships in this study.

Sclerotinia disease is important fungal disease of sunflower in Iran that reduces its growth and yield. In this study, reactions of 100 oily sunflower lines to 6 fungal isolates of Sclerotinia were studied and then 128 retrotransposon-based molecular markers (IRAP) were used to identify genes controlling disease resistance. The results showed that there is high diversity in the studied germplasm for resistance to the Sclerotinia stem rot. Population structure analysis subdivided the studied lines into 3 subpopulations (K=3). Association analysis with general and mixed linear models (GLM and MLM) identified 14 and 11 loci, respectively that aresignificantly associated (P£0.01) with Sclerotinia disease resistant genes. Markers LTR 1063-65, LTR 1064-65 and LTR 1062 were commonly associated with resistant to some fungal isolates. The common markers due to facilitating simultaneous selection for resistance to several fungal isolates can be well used in sunflower breeding programs like marker-assisted selection (MAS).

Myostatin (MSTN) is a member of the transforming growth factor-b superfamily (TGF -b) and is an important negative regulator of muscle growth in vertebrates.In this study, a partial sequence of MSTN gene (intron 1), in the camel population of Iran, was evaluated.Two single nucleotide polymorphisms and one insertion or deletion (In Dell) were identified in intron 1 of the myostatin gene, using sequencing method. The mutations caused, two substitutions including C to T and T to C in positions 16 and 136, respectively and one In Dell of T in position 218. The mutations observed in three positions of intron 1, created three different haplotypes. These haplotypes were shared among Bacterianus and Dromedaries camel populations with no haplotype restricted to a specific region or a single camel breed.Tajima D were positive for all populations except Trod station, but it wasn’t significant.