Péter Mikó

Cytomolecular discrimination of the Am chromosomes of Triticum monococcum and the A chromosomes of Triticum aestivum using microsatellite DNA repeats

The cytomolecular discrimination of the Am- and A-genome chromosomes facilitates the selection of wheat-Triticum monococcum introgression lines. Fluorescence in situ hybridisation (FISH) with the commonly used DNA probes Afa family, 18S rDNA and pSc119.2 showed that the more complex hybridisation pattern obtained in T. monococcum relative to bread wheat made it possible to differentiate the Am and A chromosomes within homoeologous groups 1, 4 and 5. In order to provide additional chromosomal landmarks to discriminate the Am and A chromosomes, the microsatellite repeats (GAA)n, (CAG)n, (CAC)n, (AAC)n, (AGG)n and (ACT)n were tested as FISH probes. These showed that T. monococcum chromosomes have fewer, generally weaker, simple sequence repeat (SSR) signals than the A-genome chromosomes of hexaploid wheat. A differential hybridisation pattern was observed on 6Am and 6A chromosomes with all the SSR probes tested except for the (ACT)n probe. The 2Am and 2A chromosomes were differentiated by the signals given by the (GAA)n, (CAG)n and (AAC)n repeats, while only (GAA)n discriminated the chromosomes 3Am and 3A. Chromosomes 7Am and 7A could be differentiated by the lack of (GAA)n and (AGG)n signals on 7A. As potential landmarks for identifying the Am chromosomes, SSR repeats will facilitate the introgression of T. monococcum chromatin into wheat.

Selection of winter durum genotypes grown under conventional and organic conditions in different European regions

Quality and agronomic performance of 14 winter durum wheat genotypes (Gs) were examined in Austria, France and Hungary for 3 years. Heading time, wet gluten content, semolina yield and grain protein content are traits that showed G-dependent significant differences between the two management (M) systems examined (conventional and organic). Therefore, breeding for these traits could result in specifically adapted Gs for organic agriculture in different countries. Based on strong or moderately significant correlations between traits, gluten index and plant height could also be specifically selected in an indirect way. The need for environmentally specific selection for grain yield (GY) in later generations was also demonstrated. In general, varieties that had the highest performance in a given mega-environment (E) originated from that mega-E (except for yellow index). This finding provides evidence for the influence of the selection E, whether it is the M system or the growing region. As the French site fell into a distinct mega-E, it should be handled separately. The Hungarian site was found to be an ideal test E for selecting Gs with high adaptability for most of the quality traits, while the Austrian site could be used in selecting agronomic traits. This was also reflected in the breeding origin of the best winter durum Gs for each trait. Based on these findings, a partly separate winter durum selection program is recommended for organic and low input agriculture in each country. As a consequence, specific varieties adapted to sub-optimal growing conditions would support the emerging movement towards sustainable farming systems.

Dataset on the mean, standard deviation, broad-sense heritability and stability of wheat quality bred in three different ways and grown under organic and low-input conventional systems.

An assessment was previously made of the effects of organic and low-input field management systems on the physical, grain compositional and processing quality of wheat and on the performance of varieties developed using different breeding methods (“Comparison of quality parameters of wheat varieties with different breeding origin under organic and low-input conventional conditions” [1]). Here, accompanying data are provided on the performance and stability analysis of the genotypes using the coefficient of variation and the ‘ranking’ and ‘which-won-where’ plots of GGE biplot analysis for the most important quality traits. Broad-sense heritability was also evaluated and is given for the most important physical and quality properties of the seed in organic and low-input management systems, while mean values and standard deviation of the studied properties are presented separately for organic and low-input fields.

Stability analysis of wheat populations and mixtures based on the physical, compositional and processing properties of the seeds

Six cropping populations, three variety mixtures and one diversity population were developed from winter wheat varieties and studied for physical, compositional and end-use quality traits for three years (2011–2013) under different European climatic and management conditions in order to study the stability of these traits resulted by the genetic diversity. The beneficial compositional and nutritional properties of the populations were assessed, while variation and stability of the traits were analysed statistically. No significant differences were found among the populations in low-input and organic management farming systems in the physical, compositional and processing properties, but there was a difference in the stability of these traits. Most of the populations showed higher stability than the control wheat variety, and populations developed earlier had higher stability than those developed later. Furthermore, some populations were found to be especially unstable for some traits at certain sites (mostly at Austrian, Swiss and UK organic sites). Protein content of the populations was high (13.0–14.7%) without significant difference among them, but there was significant variation in their gluten content (28–36%) and arabinoxylan content (14.6–20.3 mg/g). The most outstanding population for both protein and arabinoxylan content was a Hungarian cropping population named ELIT-CCP. It was concluded that the diversity found in the mixtures and CCPs have stabilizing effect on the quality parameters, but a higher stability was observed under low-input than under organic conditions. These results could be beneficial not only for breeders but also for the consumers in the long run.

Effects of Organic and Conventional Crop Nutrition on Profiles of Polar Metabolites in Grain of Wheat

The profiles of polar metabolites were determined in wholemeal flours of grain from the Broadbalk wheat experiment and from plants grown under organic and low-input systems to study the effects of nutrition on composition. The Broadbalk samples showed increased amino acids, acetate, and choline and decreased fructose and succinate with increasing nitrogen fertilization. Samples receiving farm yard manure had similar grain nitrogen to those receiving 96 kg of N/ha but had higher contents of amino acids, sugars, and organic acids. A comparison of the profiles of grain from organic and low-input systems showed only partial separation, with clear effects of climate and agronomy. However, supervised multivariate analysis showed that the low-input samples had higher contents of many amino acids, raffinose, glucose, organic acids, and choline and lower sucrose, fructose, and glycine. Consequently, although differences between organic and conventional grain occur, these cannot be used to confirm sample identity.

Application of Electrical Capacitance Method for Prediction of Plant Root Mass and Activity in Field-Grown Crops

The root electrical capacitance (CR) method is suitable for assessing root growth and activity, but soil water content (SWC) strongly influences the measurement results. This study aimed to adapt the method for field monitoring by evaluating the effect of SWC on root capacitance to ensure the comparability of CR detected at different SWC. First a pot experiment was conducted with maize and soybean to establish CR–SWC functions for the field soil. Ontogenetic changes in root activity were monitored under field conditions by simultaneously measuring CR and SWC around the roots. The CR values were normalized using SWC data and experimental CR–SWC functions to obtain CR*, the comparable indicator of root activity. The effect of arbuscular mycorrhizal fungi (AMF) inoculation on the CR* and biomass of field-grown soybean was investigated. The pot trial showed an exponential increase in CR with SWC. CR–SWC functions proved to be species-specific. CR showed strong correlation with root dry mass (R2 = 0.83–0.87). The root activity (CR*) of field-grown crops increased until flowering, then decreased during maturity. This was consistent with data obtained with other methods. AMF inoculation of soybean resulted in significantly higher CR* during the late vegetative and early flowering stages, when destructive sampling concurrently showed higher shoot biomass. The results demonstrated that the root capacitance method could be useful for time course studies on root activity under field conditions, and for comparing single-time capacitance data collected in areas with heterogeneous soil water status.