Tissue specific responses alter the biomass accumulation in wheat under gradual and sudden salt stress

Salinity is one the major limiting environmental factors which has negative side effects on crop production. The purpose of this study was to investigate the differences between the gradual and sudden salt stress effects on biomass accumulation associated with whole plant development in three different tissues of two wheat species ( Triticum aestivum and Triticum durum) under hydroponic conditions in the long term. Considering the effects of sudden and gradual stress for biomass accumulation, while importance of salinity x genotype interaction for fresh weights was 5%, association for salinity x tissue type was found as 1% important. Interestingly, root branching and development of lateral roots were much more negatively affected by gradual stress rather than sudden salt application. Our results demonstrated that root and leaf were both critical tissues to test the salt tolerance by physiologically but sheath tissue might be used as an alternative source of variation for solving the interactions between root and leaves in wheat

Genetic analysis of microsatellite markers for salt stress in two contrasting maize parental lines and their RIL population

Salt stress considerably hinders the growth and productivity of maize (Zea mays L.). Identification of salt tolerant genotypes and integration of alternative molecular markers have important roles in enhancing breeding processes. In this study, 3308 maize expressed sequence tags (ESTs) from salt stress-related libraries were assembled to mine repetitive sequences for development of applicable markers. In this core EST data, 208 simple and 18 non-simple repetitive regions were detected in 312 contigs and 1121 singletons. The di-nucleotide repeats were the most abundant type and accounted for 79.3%, followed by tri (19.7%), and tetra-nucleotide (1%). Among 59 EST-simple sequence repeats (SSRs), a total of 55 were screened for polymorphism between F35 (salt sensitive) and F63 (salt tolerant) parents and 48 out of 55 were detected as monomorphic. Significantly, seven of them (12.7%) were found to be polymorphic and were used for genotyping of 158 F5 derived recombinant inbred maize lines, and four of them were located on chromosome 1 and 3. Using in silico mapping, 44 out of 59 EST-SSR markers were mapped on 10 maize chromosomes. Analysis of sequence homology revealed different functional groups such as: membrane transport, cell defense, cell division, signaling components, photosynthesis and cell metabolism. These EST-SSRs might be used as new functional molecular markers in the diversity analysis, identification of quantitative trait loci (QTLs) and comparative genomic studies in maize in the future

An EPR study on radiation-induced 4-hydroxyphenyl-acetic acid polycrystalline

To determine of irradiation effect on 4-hydroxyphenyl-acetic acid polycrystalline, electron paramagnetic resonance (EPR) measurements were carried out. Two samples were used, which were given dose of 22.8 and 49 kGy by gamma rays using Co-60-source. EPR signals were not observed from irradiated sample, taken dose of 22.8 kGy. The measurements were performed on the sample, absorbed dose of 49 kGy, at the temperature between 120 K and 450 K. The two radical structures were suggested within experimental error. Though the radicals are identical, it was determined that they have different EPR parameters. It was observed that the intensities of the EPR spectra were to be dependent on the temperature. Also, in this study, it was aimed to test success of the machine learning methods to select the best method can be implemented theoretically. (C) 2015 Elsevier B.V. All rights reserved.Scientific Research Projects Coordination Center of Alanya Alaaddin Keykubat University, TurkeyAlanya Alaaddin Keykubat University; Scientific Research Projects Coordination Center of Selcuk University, TurkeySelcuk UniversityThis study was partially supported by the Scientific Research Projects Coordination Centers of Alanya Alaaddin Keykubat and Selcuk Universities, Turkey