Improvement of wheat abiotic stress resistance via genetic transformation

Aldose reductase gene (ALR) isolated from alfalfa (MsALR), was constructed into a plant expression vector (pAHC), and then named as pAHALR. Wheat suspension culture was bombarded with this plasmid and the transformed calli were cultured and selected on medium containing 10mg/L Bialaphos (15% glufozinate-ammonium) as a selective agent. For the molecular analysis of putative transgenic samples, PCR, Southern and Western blots were carried out. Also aldose reductase enzyme activity was detected by HPLC only in the transgenic callus samples by the accumulation of sorbitol, which is the end product of aldose reductase catalyzed glucose reduction reaction. Protective function of ALR was verified by malondialdehyde analysis under stress condition. The activity of the ALR gene will also be investigated on the transgeneic plants by biochemical and physiological analysis

Factors influencing the efficiency of wheat anther culture

Using in vitro androgenesis serves as a unique opportunity to produce doubled haploid (DH) plants in many species. More benefits of this biological phenomenon have kept these methods in the focus of fundamental research and crop breeding for decades. In common wheat (Triticum aestivum L.), in vitro anther culture is one of the most frequently applied DH plant production methods. The efficiency of in vitro wheat anther culture is influenced by many factors, such as the genotype, growing conditions, collection time, pre-treatments, and compositions of media and culture conditions. According to some critical review, the genotype dependency, low efficiency and albinism are mentioned as limitations of application of the anther culture method. However, some research groups have made significant efforts to diminish the effects of these bottlenecks. Due to the improvements, a well-established in vitro anther culture method can be an efficient tool in modern wheat breeding programs

Monitoring drought responses of barley genotypes with semi-robotic phenotyping platform and association analysis between recorded traits and allelic variants of some stress genes

Genetic improvement of complex traits such as drought adaptation can be advanced by the combination of genomic and phenomic approaches. Semi-robotic phenotyping platform was used for computer-controlled watering, digital and thermal imaging of barley plants grown in greenhouse. The tested barley variants showed 0–76% reduction in green pixel-based shoot surface area in soil with 20% water content, compared to well-watered plants grown in soil with 60% water content. The barley HvA1 gene encoding the group 3 LEA (Late Embryogenesis Abundant) protein exhibited four (A–D) haplotypes as identified by the EcoTILLING and subsequent DNA sequencing. The green pixel mean value of genotypes with haplotype D was higher than the mean value of the remaining haplotypes, indicating a pivotal role of haplotype D in optimizing the green biomass production under drought condition. In water limitation, the canopy temperature of a highly sensitive genotype was 18.0°C, as opposed to 16.9°C of leaves from a tolerant genotype as measured by thermal imaging. Drought-induced changes in leaf temperature showed moderate correlation with the water use efficiency (r2 = 0.431). The haplotype/trait association analysis based on the t-test has revealed a positive effect of a haplotype B (SNPs:GCCCCTGC) in a gene encoding the barley fungal pathogen induced mRNA for pathogen-related protein (HvPPRPX), on harvest index, thousand grain weight, water use efficiency and grain yield. The presented pilot study established a basic methodology for the integrated use of phenotyping and haplotyping data in characterization of genotype-dependent drought responses in barley

Víztakarékos öntözéstechnikával termeszthető rizsfajtákra jellemző génexpressziós mintázatok = Gene expression profiles characteristic to rice varieties cultivated under water-saver irrigation regime

Eltérő vízigényű rizsfajták (''szárazrizsek'' és hagyományos fajták) növekedési, termesztési paramétereit határoztuk meg árasztásos ill csak kiegészítő öntözéses körülmények között annak érdekében, hogy a korlátozott vízellátáshoz jól adaptálódó fajtákra jellemző tulajdonságokat megállapíthassuk. Kidolgoztunk egy olyan kísérleti rendszert, melyben ezeknek a fajtáknak a gyökérnövekedését vizsgálhatjuk, illetve génexpressziós vizsgálatokhoz mintát gyűjthetünk. Transzkript profilok microarray hibridizációs felvételével megállapítottuk, hogy a mélyrehatoló, erőteljes gyökérzet meghatározó jellemzője a száraz körülmények között is jól teljesítő fajtáknak, és több száz olyan gént találtunk, melynek transzkript-szintje vízellátástól függő napszakos változásokat mutat a legnagyobb tűrőképességű Sandora fajta gyökérzetében. Valósidejű kvantitatív PCR-rel ellenőriztük számos gén expressziós mintázatát, ez döntő többségében megerősítette a microarray hibridizációval kapottakat, egyúttal más aszályérzékenységű rizsfajtákban is meghatároztuk ezen gének expressziós mintázatát. | Rice cultivars featuring different water demand (upland and traditional cultivars) were studied in this project. Growth and harvest parameters of these cultivars were determined under flooding and limited sprinkle irrigation in order to find features characteristic to genotypes adapting well to water limitation. An experimental system was established that allows studies of root growth as well as collection of samples for gene expression experiments. Microarray hybridizations revealed the transcript profile of Sandora cultivar that develops strong and deep root system which is an important component of good yield performance under drought stress. Several hundred genes were found which showed water supply dependent transcript level changes in the roots of this cultivar on a daily manner. Microarray results were confirmed by quantitative real-time PCR for several genes. The expression patterns of these genes were also checked in cultivars being less drought tolerant

Androgenesis induction in microspore culture of sweet pepper (Capsicum annuum L.)

Isolated microspore culture experiments were carried out in sweet pepper (Capsicum annuum L.) F1 hybrid genotypes. In the first experiment, four culture media (W14, B5, MS and NLN) were compared to test their effectiveness in inducing the formation of microsporederived structures in two genotypes. The experiments revealed the superiority of B5 medium. In the second experiment, the effects of different ratios of 2,4-dichlorophenoxyacetic acid (2,4-D) (0, 0.1, 0.2 and 0.5 mg l-1) and kinetin (0, 0.2 and 0.5 mg l-1) were also investigated in B5 medium with two genotypes. The effect of growth regulators were investigated on the production of microsporederived calli and embryo-like structures (ELSs), the ratio of the two and plant regeneration (number of regenerated plantlets) in microspore culture. The histological experiments revealed the differences between the microsporederived ELSs and calli. The most promising results were obtained on the investigated parameters in the presence of 0.1 mg l-1 2,4-D and 0.2 mg l-1 kinetin producing the highest number of plantlets in both genotypes tested. In the response of 11 genotypes, the androgenesis induction was successful in each sweet pepper genotypes tested using the best basic medium and growth regulators combination. In case of 11 genotypes, the number of ELSs ranged from 20 to 100/Petri dish (an average of 48.1 ELS/Petri dish), while the number of green plantlets varied from 0 to 8 plantlets/Petri dish (an average of 1.5 plantlets/Petri dish) depending on the genotype. The spontaneous rediploidization rate obtained was 25% in isolated microspore