Phenotypical and physiological study of near-isogenic durum wheat lines under contrasting water regimes

Irrigation treatments involving two water regimes were carried out in a controlled environment on eight nearisogenic durum wheat lines that differed in a major yield-related QTL region (QYld. idw-3B) in order to assess the relationship between morpho-physiological traits, antioxidant enzyme activities, and polyamine contents in the flag leaves, and drought tolerance. Drought stress, simulated under a rain-out shelter, negatively affected the performance of the isogenic lines, leading to significant reductions in seed yield, tiller number, chlorophyll content, plant height, leaf area, and ascorbate peroxidase activity, while the polyamine content and guaiacol peroxidase activity increased. The ascorbate peroxidase activity was negatively correlated with seed weight per main (r = -0.446) and side spike (r = -0.465) and the 1000-grain weight of the main and side spike (r = -0.396 and r = -0.49, respectively) and the guaiacol peroxidase activity with the number of seeds per main (r = -0.457) and side spike (r = -0.378) and the seed weight per side spike (r = -0.38). PUT, SPD, and SPN contents showed a significant positive relationship with the number of seeds per main spike (0.534***, 0.496***, and 0.481**, respectively) and the seed weight per main spike (0.383*, 0.352*, and 0.399**, respectively). ANOVA showed that the QYld. idw-3B++ lines had significantly better yield performance under non-watered conditions than the QYld. idw-3B--lines, but their response to drought stress was not uniform regarding other yield-related traits. (C) 2016 SAAB. Published by Elsevier B.V. All rights reserved

Identification of superior spring durum wheat genotypes under irrigated and rain-fed conditions

An important objective of wheat improvement programmes is to breed varieties for high yield in optimum conditions and for minimum yield reduction under stress-prone conditions such as heat and drought. Analyses of yield and its components in multiple years allow a comprehensive and comparative understanding of genetic yield potential and stress-tolerance mechanisms in the study germplasm. The present study was carried out to evaluate performance of elite varieties and landraces of spring durum wheat under different water regimes, determine the repeatability of the examined traits, and identify superior genotypes for their potential use in breeding for drought tolerance. A total of 97 accessions of spring durum wheat (T. durum Desf.) were evaluated under rain-fed and well-watered conditions in the nursery of the Centre for Agricultural Research at Martonvasar, Hungary (2011-2013). The experiments were laid out in an unbalanced, incomplete alpha lattice block design. The trait with the lowest broad-sense repeatability was seed length (0.075), while high h(2) values were observed for heading date (0.89), thousand-grain weight (0.85) and the protein content (0.85). Grain yield showed moderate level of repeatability (0.53) across the three years. The principal component analysis revealed that grain yield (t/ha) is positively associated with the fertile tiller number, chlorophyll content values at early waxy ripeness stages and plant height. Based on biplot analysis, 'DP-133 ', 'DP-017 ' and 'DP-061 ' proved to be the best durum cultivars in terms of yield whereas genotypes 'DP-011 ', 'DP-185 ', 'DP-126 ' and 'DP-136 ' preceded them with their good yield stability

Bioinformatics tool for handling molecular data in wheat breeding

The research institute in Martonvásár is one of the largest agricultural research institutes in Hungary and in Central Europe. For many years now, the accumulated data on the extensive wheat breeding stocks has been handled and analysed using programs developed in the institute. The information system that has been elaborated and constantly improved can be used for keeping records of breeding stock, for planning field and laboratory experiments, for site-plant performance evaluation, for automated data collection, for the rapid evaluation of the results and for effective management of the pedigree, seed exchange and the institute’s cereal gene bank. The demand for the storage of molecular data and their use in breeding has increased parallel with the development of new, PCR-based markers. For this reason, informatics tools (data structure and software) suited to the design of marker-assisted selection experiments and the interpretation of the results have been developed as part of the existing Martonvásár wheat breeding information system. The aim was to link molecular data to the phenotypic information already available in the database and to make the results available to wheat breeders and geneticists. The interpretation of molecular data related to specific genotypes is of assistance in clarifying the genetic background of economically important phenotypic traits, in identifying markers linked to the useful genes or agronomic traits to be found in the genomics database, and in the selection of satisfactory parental partners for breeding. Marker assisted selection coupled with traditional breeding activities enables the breeder to make plant selections based on the presence of target genes. Conventional wheat breeding with the integrated molecular component allows breeders to more accurately and efficiently select defined sets of genes in segregating generations. The molecular data are stored in a relational database, the central element of which is the [DNASource] entity. This is used to collect and store information on gene sources arising during breeding. It is therefore linked both to the phenotypic data stored in the traditional breeding system (measurements, observations, laboratory data) and to the component parts of the new, molecular data structure ([PrimerBank], [Marker], [Allele] and [Gene])