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Drought is an important abiotic stress factor limiting crop productivity worldwide and its impact is increasing with climate change. Regardless of the plant growth period, drought has a deadly and yield-reducing effect on the plant at every stage of development. As with many environmental stressors, drought-exposed plants trigger a series of molecular, biochemical, and physiological responses to overcome the effect of drought stress. Currently, researchers are trying to determine the complex functioning of drought stress response in plants with different approaches. Plants are more sensitive to drought stress during certain critical stages like germination, seedling formation, flowering, fertilization, and grain formation periods. Plants have high success in reducing the effects of drought stress in vegetative development periods with the activity of tolerance mechanisms. On the other hand, drought stress during the generative period can cause irreversible losses in yield. This review focuses on the progression of molecular, biochemical, and physiological mechanisms involved in the drought stress tolerance in plants and the responses of field crops to drought stress at different development stages.

Salinity is an abiotic stress factor that reduces yield and threatens food security in the world's arid and semi-arid regions. The development of salt-tolerant genotypes is critical for mitigating yield losses, and this journey begins with the identification of sensitive and tolerant plants. Numerous physiologic and molecular markers for detecting salt-tolerant wheat genotypes have been developed. One of them is proline, which has been used for a long time but has received little information about proline-related genes in wheat genotypes. In this study, proline content and the expression levels of proline-related genes (

The effects of protists on an indigenous soil bacterial community, putative bacterial genes involved in N-cycling, and the rice plant growth were studied in poultry litter biochar (PL) and rice husk biochar (RH) amended (with two application doses: 2% and 4% w/w) paddy field soil. The bacterial community composition, which was evaluated using 16S rRNA gene amplicon sequencing, was significantly and differentially affected by the protists, the PL and the RH. The effects of protists on the bacterial community composition were decreased by the RH and the PL treatments. The number of protist-affected bioindicator bacterial taxa was decreased from 90 to 46, 29, 43, and 21 in the 2% RH-, 4% RH-, 2% PL-, and 4% PL-treated soils, respectively. The presence of the protist significantly increased the abundance of the putative bacterial genes involved in mineralisation, dissimilatory nitrate reduction to ammonium (DNRA), and NO3- assimilation, and the same occurred with PL treatments. The rice plant growth and N uptake were always higher in the presence of protists and PL amendments. Overall our results suggest a new insight into the effects of biochar on the bacterial community via altering the trophic interactions.

Potato (Solanum tuberosum L.) is one of the major crops of the world. Significant improvements can be achieved in terms of yield and quality by the determination of efficient transformation methods. On the other hand, low transformation frequency seriously limits the application of molecular techniques in obtaining transgenic crops. In the present study, the effect of gamma radiation on Agrobacterium tumefaciens-mediated transformation to the potato was firstly investigated. Sterile seedlings of potato cv. ‘Marabel’, which was grown on Gamborg’s B5 medium in Magenta vessels, were irradiated with different gamma radiation doses (0-control, 40, 80, 120 Gy 60Co). Stem parts having axillary meristems were excised from irradiated seedlings and inoculated by A. tumefaciens (GV2260), which harbors the binary plasmid p35S GUS-INT contains and GUS (β-glucuronidase) gene controlled by 35S promoter (CaMV) and nptII (neomycin phosphotransferase II) gene driven by NOS (nopaline synthase) promoter). Inoculated stem parts having axillary meristems explants were then directly transported to a selection medium containing duocid (500 mg l−1), and kanamycin (100 mg l−1), 4 mg l−1 gibberellic acid, 1 mg l−1 BAP and 0.1 mg l−1 NAA. The adult transgenic plants were detected by polymerase chain reaction (PCR) analysis. According to the number of transgenic plants determined by PCR analysis, results obtained from explants treated with 40 Gy gamma gave the best results compared to the control (0 Gy) application. The doses over 40 Gy were also found statistically significant compared to the control (0 Gy). It is expected that the protocol described in this study make the transformation studies easier by skipping the stages of ‘co-cultivation’, ‘culturing explants on selection medium’ and ‘recovery of transgenic shoots on selection medium’ not only for potato but also for other crop plants. This study was supported by a grant from the Scientific and Technological Research Council of Turkey (TUBİTAK) (Grant number 113O280 to Prof. Dr. Mustafa YILDIZ).

The loss of cropland soils, climate change, and population growth are directly affecting the food supply. Given the higher incidence of salinity and extreme events, the cereal performance and yield are substantially hampered. Wheat is forecast to decline over the coming years due to the salinization widespread as one of the oldest and most environmental severe constraints facing global cereal production. To increase salinity tolerance of wheat, in this study, we developed two new salt-tolerant bread wheats, named 'Maycan' and 'Yildiz'. The salinity tolerance of these lines, their parents, and a salt-sensitive cultivar has been tested from measurements of physiological, biochemical, and genes associated with osmotic adjustment/plant tolerance in cultures containing 0 and 150 mM NaCl at the seedling stage. Differential growth reductions to increased salinity were observed in the salt-sensitive cultivar, with those newly developed exhibiting significantly greater root length, growth of shoot and water content as salinity tolerances overall than their parents. 'Maycan' and 'Yildiz' had higher osmoregulator proline content and antioxidants enzyme activities under salinity than the other bread wheat tested. Notably, an important upregulation in the expression of genes related to cellular ion balance, osmolytes accumulation, and abscisic acid was observed in both new wheat germplasms, which may improve salt tolerance. These finding revealed that 'Maycan' and 'Yildiz' exhibit high-salt tolerance at the seedling stage and differing in their tolerance mechanisms to the other tested cultivars, thereby providing an opportunity for their exploitation as modern bread wheats.

Maternal effects are ubiquitous in nature and have been demonstrated in a wide array of traits and taxa. In many species, the genotype of the mother is a major determinant of the phenotype of her offspring. In plants, less is known about the levels of sensitivity to stresses-mediated maternal effects. We generated 12 reciprocal crossed F2 lines from two salt-tolerant and two salt-sensitive wheat cultivars to distinguish the influence of the maternal effect from the influence of the offspring genome on the expression of offspring traits under high-salinity (250 mM NaCl). SSR markers screening of the reciprocal hybrid genotypes and parents’ nuclear genomes and Sanger sequencing of low-, medium-, and high-dominant markers revealed insignificant changes in the nuclear genome among offspring and parents. However, interestingly, the offspring with salt-tolerant mothers showed higher salt tolerance than those with salt-sensitive mothers. This study shed light on still unresolved fundamental questions regarding the potential of maternal genetic effects contribute to stress tolerance and the non-completely control by nuclear genetic factors, which may open future research avenues as a source of a quality shift in subsequent offspring that any genetic analysis of tolerance traits must consider.

Next-generation sequencing (NGS) is a revolutionary advancement allowing large-scale discovery of functional molecular markers that has many applications, including plant breeding. High-quality genomic DNA (gDNA) is a prerequisite for successful NGS library preparation and sequencing; however, few reliable protocols to obtain such plant gDNA exist. A previously reported nuclear pellet (NP) method enables extraction of high-yielding gDNA from fresh leaf tissue of maize (Zea mays L.), but the quality does not meet the stringent requirements of NGS. In this study, we optimized the NP method for whole-genome sequencing of rice (Oryza sativa L.) through the integration of simple purification steps. The optimized NP method relied on initial nucleus enrichment, cell lysis, extraction, and subsequent gDNA purification buffers. The purification steps used proteinase K, RNase A, phenol/chloroform/isoamyl alcohol (25:24:1), and chloroform/isoamyl alcohol (24:1) treatments for protein digestion and RNA, protein, and phenol removal, respectively. Our data suggest that this optimized NP method allowed extraction of consistently high-yielding and high-quality undegraded gDNA without contamination by protein and RNA. Moreover, the extracted gDNA fulfilled the quality metrics of NGS library preparation for the Illumina HiSeq X Ten platform by the TruSeq DNA PCR-Free Library Prep Kit (Illumina). We provide a reliable step-by-step guide to the extraction of high-quality gDNA from fresh leaf tissues of rice for molecular biologists with limited resources.

WOS: 000460753400004 This study was conducted to determine the effects of magnetic field (MF) strength on shoot regeneration and Agrobacterium tumefaciens-mediated gene transfer in flax (Linum usitatissimum L.). Seeds of flax cv. Madaras were exposed to different MF strengths (0 - control, 75, 150, and 300 millitesla (mT)) for 24 h by using an electromagnetic generator system fabricated in laboratory conditions. After sterilization, seeds were germinated on MS (Murashige and Skoog) medium in Magenta vessels. Hypocotyl explants excised from 7-days-old seedlings were used for regeneration. GV2260 strain of Agrobacterium tumefaciens was used in transformation studies. Inoculated hypocotyls were cultured on MS medium containing 1 mg/l BAP (6-benzylaminopurine) and 0.02 mg/l NAA (naphthaleneacetic acid) for 2 days by co-cultivation. Then, they were transferred to MS medium containing the same growth regulators, 100 mg/l kanamycin and 500 mg/l Duocid for selection. The presence of the nptII gene was verified by PCR (polymerase chain reaction) analysis in putative transgenic plants. The highest results with respect to shoot regeneration and transformation frequency were obtained from treatments of 75 mT MF strength. Scientific and Technological Research Council of Turkey (TUBITAK)Turkiye Bilimsel ve Teknolojik Arastirma Kurumu (TUBITAK) [113O280] This investigation was supported by Scientific and Technological Research Council of Turkey (TUBITAK); Grant No. 113O280 to Prof. Dr. M. YILDIZ

European Biotechnology Congress -- MAY 25-27, 2017 -- Dubrovnik, CROATIA WOS: 000413585400114 … Ahi Evran University Scientific Research Projects Coordination Unit [ZRT.E2.17.007] This work was supported by Ahi Evran University Scientific Research Projects Coordination Unit. Project Number: ZRT.E2.17.007.

In this study, routinely used transformation method, which includes transferring explants onto co-cultivation medium after inoculating them with bacterial solution for a while, was compared with 3 different inoculation methods. In every 3 methods, hypocotyl explants excised from 7-day-old sterile flax seedlings having cotyledon leaves and no root system dried under air flow in sterile cabin for 35 min were inoculated with different volumes of bacterial solution at different inoculation periods. GV2260 line of Agrobacterium tumefaciens having 'pBIN 19' plasmid containing npt II (neomycin phosphotransferase II) gene and GUS reporter gene was used in transformation studies. After inoculation, hypocotyl segments of seedlings (0.5 cm in length)-were excised and left to co-cultivation for 2 days. Then, explants were transferred to regeneration medium supplemented with different antibiotics. The presence of npt-II and GUS genes in transformants was confirmed by PCR and GUS analysis. The highest results in all characters examined in all cultivars were obtained from the 2 inoculation method in which hypocotyls excised from seedlings inoculated with 500 µl of bacterial solution after drying in sterile cabin for 35 min were used. © Korean Society for Plant Biotechnology.

In this research, the antibacterial activity of crude extracts obtained from leaves of pennyroyal (Mentha pulegium L.) plant against Escherichia coli ATCC 25922, Enterococcus faecalis ATCC 29212, Staphylococcus aureus ATCC 29213 and Staphylococcus epidermidis ATCC 12228 was investigated. Acetone and methanol were used as chemical solvents to prepare the extracts of Mentha pulegium L. The determination of antibacterial activity was performed by using disc diffusion method. For each extract, its own solvent was utilized as negative control. Standard antibiotic discs (Clindamycin, Tetracycline and Amoxicillin-Clavulanic acid) were also used as positive control. The results of present study showed that the crude extracts of Mentha pulegium L. prepared in acetone and methanol had antibacterial activity against test microorganisms and the most antibacterial effect was observed against Staphylococcus epidermidis. It was determined that the extract of Mentha pulegium L. (6400 µg/disc) has more antibacterial activity against E. faecalis and S. epidermidis than Tetracycline (10 µg/disc) and has more antibacterial activity against E. coli than Clindamycin (10 µg/disc). However it was found that antibacterial activity of Mentha pulegium L. extract (6400 µg/disc) was close to Tetracycline (10 µg/disc) for E. coli and S. aureus and was close to Clindamycin (10 µg/disc) for E. faecalis.