Yield and Quality in Purple-Grained Wheat Isogenic Lines

Breeding programs for purple wheat are underway in many countries but there is a lack of information on the effects of Pp (purple pericarp) genes on agronomic and quality traits in variable environments and along the product chain (grain-flour-bread). This study was based on unique material: two pairs of isogenic lines in a spring wheat cv. Saratovskaya-29 (S29) background differing only in Pp genes and grain color. In 2017, seven experiments were conducted in Kazakhstan, Russia, and Turkey with a focus on genotype and environment interaction and, in 2018, one experiment in Turkey with a focus on grain, flour, and bread quality. The eect of environment was greater compared to genotype for the productivity and quality traits studied. Nevertheless, several important traits, such as grain color and anthocyanin content, are closely controlled by genotype, offering the opportunity for selection. Phenolic content in purple-grained lines was not significantly higher in whole wheat flour than in red-colored lines. However, this trait was significantly higher in bread. For antioxidant activities, no differences between the genotypes were detected in both experiments. Comparison of two sources of Pp genes demonstrated that the lines originating from cv. Purple Feed had substantially improved productivity and quality traits compared to those from cv. Purple

Opportunities in Tajikistan to breed wheat varieties resistant to seed-borne diseases and improved baking quality

Wheat seed-borne diseases and options for improving baking quality of wheat, as well as the role of genotypes for breeding to achieve high yield and quality are the key issues discussed in this introductory paper. The importance of wheat for Tajikistan and how to achieve food security goals in the country is also elucidated. Wheat seed-borne diseases are caused mostly by fungi. Loose Smut (Ustilago tritici), Common Bunt (Tilletia laevis and T.caries), Karnal Bunt (T.indica), Dwarf Bunt (T.controversa) and Black point (Alternaria spp., Bipolaris sorokiniana etc.) are all seed-borne diseases that are economically and regulatory important for Tajikistan, and these are therefore discussed in detail. The peculiarities of Tajik bread and requirements to the grain quality are also highlighted

Transcriptome pathways unique to dehydration tolerant relatives of modern wheat

Among abiotic stressors, drought is a major factor responsible for dramatic yield loss in agriculture. In order to reveal differences in global expression profiles of drought tolerant and sensitive wild emmer wheat genotypes, a previously deployed shock-like dehydration process was utilized to compare transcriptomes at two time points in root and leaf tissues using the Affymetrix GeneChip(R) Wheat Genome Array hybridization. The comparison of transcriptomes reveal several unique genes or expression patterns such as differential usage of IP(3)-dependent signal transduction pathways, ethylene- and abscisic acid (ABA)-dependent signaling, and preferential or faster induction of ABA-dependent transcription factors by the tolerant genotype that distinguish contrasting genotypes indicative of distinctive stress response pathways. The data also show that wild emmer wheat is capable of engaging known drought stress responsive mechanisms. The global comparison of transcriptomes in the absence of and after dehydration underlined the gene networks especially in root tissues that may have been lost in the selection processes generating modern bread wheats

Cell membrane stability- an important criterion for selection of heat tolerant genotypes in wheat (Triticum aestivum L.)

Cell membrane stability, grain filling rate, grain filling duration, canopy temperature and grain yield were used to evaluate performance of 100 diverse bread wheat (Triticum aestivum L.) genotypes under timely sown and late sown heat stress conditions for two cropping season. The genotypes differed significantly for all the traits show-ing considerable variation for improvement of characters. The genotypes WH1165 had significant high grain yield (14.6* g and 11.4g) and (11.3* g and 11.4* g) followed by cell membrane stability under timely sown and heat stress conditions, respectively indicating potential tolerance against heat stress. Correlation coefficients revealed that cell membrane stability (0.451**) and (0.639**) in timely sown and in late sown conditions, respectively were the most important trait followed by grain filling rate (0.882** and 0.744**) under timely sown and late sown conditions respec-tively. Results revealed that bread wheat genotypes which had high value of cell membrane stability had high grain yield showed potential photorespiration and high grain filling rate under heat stress condition. Twenty two genotypes WH1021, WH1155, VL803, WH787, NW1014, Raj3765, HD1869, 2042, WH1124, HD2285, WH1133, HUW234, 4066, Sonak, UP2425, UP2473, PBW503, PBW373, PBW533, SGP13, HD2643 and WH789 were identified as heat tolerant genotypes based on their relative performance in yield components, grain yield and heat susceptibility indi-ces. These genotypes were found to be ideal candidates to be used in developing heat tolerant wheat varieties. Canopy temperature, membrane thermostability and grain filling rate have also shown strong correlation with grain yield. Because of this association, these traits constitute the best available ‘tool’ for genetic improvement of wheat suitable for cultivation under heat stressed environments. Thus, these could be used as indirect selection criteria for developing heat tolerant wheat genotypes that would provide sufficient yields to meet the ever increasing wheat demand

Genotypic variation in phosphorus efficiency between wheat cultivars grown under greenhouse and field conditions

Phosphorus (P) efficiency (relative growth), which is described as the ratio of shoot dry matter or grain yield at deficient P supply to that obtained under adequate P supply, was compared in 25 winter wheat cultivars grown under greenhouse and field conditions with low and adequate P levels in a P-deficient calcareous soil. Adequate P supply resulted in significant increases in shoot dry weight and grain yield under both experimental conditions. In the greenhouse experiment, the increases in shoot dry weight under adequate P supply (80 mg kg(-1)) were from 0% (cv: C-1252) to 34% (cv: Dagdas). Under field conditions, the cultivars showed much greater variation in their response to adequate P supply (60 kg ha(-1)): the increases in shoot dry weight and grain yield with adequate P supply were between -2% (cv: Sivas-111/33) and 25% (cv: Kirac-66) for shoot dry matter production at the heading stage and between 0% (cv: Kirkpinar-79) and 76% (cv: Kate A-1) for grain yield at maturity. Almost all cultivars behaved totally different in their response to P deficiency under greenhouse and field conditions. Phosphorus efficiency ratios (relative growth) under greenhouse conditions did not correlate with the P efficiency ratios under field conditions. In general, durum wheat cultivars were found to be more P efficient compared with bread wheat cultivars. The results of this study indicated that there is wide variation in tolerance to P deficiency among wheat cultivars that can be exploited in breeding new wheat cultivars for high P deficiency tolerance. The results also demonstrated that P efficiency was expressed differently among the wheat cultivars when grown under greenhouse and field conditions and, therefore, special attention should be paid to growth conditions in screening wheat for P efficiency

Proceedings of the COST SUSVAR/ECO-PB Workshop on organic plant breeding strategies and the use of molecular markers

In many countries,national projects are in progress to investigate the sustainable low-input approach.In the present COST network,these projects are coordinated by means of exchange of materials,establishing common methods for assessment and statistical analyses and by combining national experimental results.The common framework is cereal production in low-input sustainable systems with emphasis on crop diversity.The network is organised into six Working Groups,five focusing on specific research areas and one focusing on the practical application of the research results for variety testing:1)plant genetics and plant breeding,2)biostatistics,3)plant nutrition and soil microbiology,4)weed biology and plant competition,5)plant pathology and plant disease resistance biology and 6)variety testing and certification.It is essential that scientists from many disciplines work together to investigate the complex interactions between the crop and its environment,in order to be able to exploit the natural regulatory mechanisms of different agricultural systems for stabilising and increasing yield and quality.The results of this cooperation will contribute to commercial plant breeding as well as official variety testing,when participants from these areas disperse the knowledge achieved through the EU COST Action

What breeding strategy(ies) should be carry up for organic winter wheat? Results and prospects from a long-term comparison with low input variety trials

Breeding varieties adapted to various organic farming conditions is one solution, among others, to increase yields and improve organic winter bread wheat quality. From 2004 to 2011, INRA winter wheat breeders have conducted variety trials in three contrasting agro-climatic regions across north-west France to test the relative response of 25 to 30 diversified genotypes when cultivated in low input (FI) and organic (AB) conditions. The comparison of 17 paired management trials showed the relevance of low input conditions to identify genotypes adapted to organic farming conditions for yield and protein content. Such a selection environment is useful also to screen “GPD+” (positive Grain Protein Deviation) genotypes with better nutrient use efficiency. In contrast, our results highlighted the need to evaluate genotypes baking quality in organic conditions in which bread making ability is frequently lost

Roots and Compost, - organic crop production under reduced nutrient availability

With plans to phase out manure import from conventional farms, it will become increasingly difficult to secure plant nutrients for organic crops. In the RoCo project we will address this problem through three approaches: 1) study variation in root growth and root hair formation among cultivars of wheat, onion and lettuce, to identify superior cultivars and critical root traits which can be used as breeding objectives for new cultivars for organic farming, 2) study recirculation of urban nutrient sources through composting, to make them good fertilizers and study what make them acceptable for consumers and organic farmers, and 3) with wheat baking quality as example, study whether we can solve some of the quality problems caused by nutrient limitation by the way we use the product rather than by increasing nutrient supply in the field. We will do research within all three main themes and interactions between them, i.e. whether genotypes with superior root traits are better at using nutrients from the composts, and whether some wheat genotypes vary in their ability to utilize compost to achieve god baking quality. We will develop and test improved compost products, and develop bread baking including the use of natural additives to enhance backing quality. Demonstration activities will be related to all parts of the project. Composts will be tested for different wheat types at organic farms and differences in root traits or baking quality will be demonstrated at open field days

Concentration and localization of zinc during seed development and germination in wheat

In a field experiment, the effect of foliar Zn applications on the concentration of Zn in seeds of a bread wheat cultivar (Triticum aestivum L. cv. Balatilla) was studied during different stages of seed development. In addition, a staining method using dithizone (DTZ: diphenyl thiocarbazone) was applied to (1) study the localization of Zn in seeds, (2) follow the remobilization of Zn during germination, and (3) develop a rapid visual Zn screening method for seed and flour samples. In all seed development stages, foliar Zn treatments were effective in increasing seed Zn concentration. The highest Zn concentration in the seeds was found in the first stage of seed development (around the early milk stage); after this, seed Zn concentration gradually decreased until maturity. When reacting with Zn, DTZ forms a redcolored complex. The DTZ staining of seed samples revealed that Zn is predominantly located in the embryo and aleurone parts of the seeds. After 36 h of germination, the coleoptile and roots that emerged from seeds showed very intensive red color formation and had Zn concentrations up to 200 mg kg1, indicating a substantial remobilization of Zn from seed pools into the developing roots (radicle) and coleoptile. The DTZ staining method seems to be useful in ranking flour samples for their Zn concentrations. There was a close relationship between the seed Zn concentrations and spectral absorbance of the methanol extracts of the flour samples stained with DTZ. The results suggest that (1) accumulation of Zn in seeds is particularly high during early seed development, (2) Zn is concentrated in the embryo and aleurone parts, and (3) the DTZ staining method can be used as a rapid, semiquantitative method to estimate Zn concentrations of flour and seed samples and to screen genotypes for their Zn concentrations in seeds