Maria Luisa Prieto-Linde

Effects of Wheat Cultivar and Nitrogen Application on Storage Protein Composition and Breadmaking Quality

ABSTRACT Influences of cultivar and nitrogen application on protein concentration and composition, and amount and size-distribution of different protein components, were investigated in 10 spring wheat cultivars (Triticum aestivum L.) with widely varying gluten strength, grown under four nitrogen fertilizer conditions. The results showed that cultivar differences in gluten strength were determined by storage protein composition, differences in total amount of HMW glutenin subunits, the glutenin-to-gliadin ratio, and the relationship between SDS-soluble and SDS-insoluble protein polymers. Negative correlations were found between protein parameters related to gluten strength and bread volume. No cultivar stability for gluten strength in relation to differences in nitrogen application was found. Thus, the gluten strength was influenced by the nitrogen application in all the investigated cultivars. Increased nitrogen supply correlated significantly to an increase in all protein components containing gliadins ...

Influences of cultivar, cultivation year and fertilizer rate on amount of protein groups and amount and size distribution of mono- and polymeric proteins in wheat

Influences of cultivar and environment, i.e. cultivation year and fertilizer rate, on amount of protein groups and amount and size distribution of mono- and polymeric proteins, were investigated in four sets of wheat (Triticum aestivum L.). The cultivars were chosen in order to obtain a high range of variation in protein concentration and gluten strength. Environmental influences on protein concentration and gluten strength were investigated, as well as relations between variation in protein concentration and gluten strength and variation in protein groups and amount and size distribution of mono- and polymeric proteins. The results showed that cultivar and environmental influences giving rise to variation in protein concentration also gave rise to variation in most of the investigated protein components. Protein concentration was significantly positively correlated to the total amounts of glutenins and gliadins and amounts of most mono- and polymeric proteins. However, the correlation with the amount of gliadins and sodium dodecyl sulphate (SDS)-soluble mono- and polymeric proteins were often higher than the correlation to the glutenins and the SDS-insoluble mono- and polymeric proteins. Cultivar influences giving rise to variation in gluten strength were found to influence the relation between SDS-soluble and -insoluble polymeric proteins, leading to a significant positive correlation between the gluten strength and the percentage of total unextractable polymeric protein (TUPP) in the total polymeric protein and large unextractable polymeric protein (LUPP) in the total large polymeric protein. Environmental variation in gluten strength was found to be significantly positively correlated to SDS-insoluble proteins and negatively correlated to SDS-soluble proteins. This also led to a significant positive correlation with the percentage of LUPP and/or TUPP.

Individual and interactive effects of cultivar maturation time, nitrogen regime and temperature level on accumulation of wheat grain proteins.

BACKGROUND Background and reasons for differences in wheat grain protein accumulation and polymerization are not fully understood. This study investigated individual and interactive effects of genetic and environmental factors on wheat grain protein accumulation and amount and size distribution of polymeric proteins (ASPP). RESULTS Individual factors, e.g. maturation time of a cultivar, nitrogen regime and temperature level, influenced grain protein accumulation and ASPP, although interaction of these factors had a greater influence. Early maturation time and long grain maturation period (GMP) in a cultivar resulted in high amounts of sodium dodecyl sulphate (SDS)-extractable proteins (TOTE) and low percentage of SDS-unextractable polymeric proteins in total polymeric proteins (%UPP). Cultivars with late maturation time and short GMP resulted in low TOTE and high %UPP. Late versus early nitrogen application regime resulted in low %UPP versus low TOTE and high %UPP, respectively. High versus low temperature resulted in high %UPP and low %UPP, respectively. Differences in ASPP at maturity started as changes in protein accumulation from 12 days after anthesis. CONCLUSION Length of GMP, especially in relation to length until maturity, governs gluten strength (%UPP) and grain protein concentration (TOTE). Length of GMP is determined by cultivar, temperature during GMP and late nitrogen availability.

Mineral Nutritional Yield and Nutrient Density of Locally Adapted Wheat Genotypes under Organic Production

The aim of the present investigation was to investigate the nutritional yield, nutrient density, stability, and adaptability of organically produced wheat for sustainable and nutritional high value food production. This study evaluated the nutritional yield of four minerals (Fe, Zn, Cu, and Mg) in 19 wheat genotypes, selected as being locally adapted under organic agriculture conditions. The new metric of nutritional yield was calculated for each genotype and they were evaluated for stability using the Additive Main effects and Multiplicative Interaction (AMMI) stability analysis and for genotypic value, stability, and adaptability using the Best Linear Unbiased Prediction (BLUP procedure). The results indicated that there were genotypes suitable for production under organic agriculture conditions with satisfactory yields (>4000 kg·ha−1). Furthermore, these genotypes showed high nutritional yield and nutrient density for the four minerals studied. Additionally, since these genotypes were stable and adaptable over three environmentally different years, they were designated “balanced genotypes” for the four minerals and for the aforementioned characteristics. Selection and breeding of such “balanced genotypes” may offer an alternative to producing nutritious food under low-input agriculture conditions. Furthermore, the type of evaluation presented here may also be of interest for implementation in research conducted in developing countries, following the objectives of producing enough nutrients for a growing population.

Breeding for Stability in Bread Milling Quality

Both genotype and environment influence on the bread-making quality of wheat and a better stability in quality is desired. In order to better understand the variation in bread-making quality, protein composition and amount and size distribution of different protein compounds were investigated. The results showed that:

Evaluation of microsatellite-based genetic diversity, protein and mineral content in chickpea accessions grown in Kyrgyzstan

The genetic diversity of 23 chickpea accessions representing Kyrgyz landraces and cultivars, ICARDA breeding lines, Spanish and Turkish cultivars was characterized using nine microsatellite (SSR) markers which generated a total of 122 alleles. The number of alleles (Na) per locus varied from 9 to 20. The observed heterozygosity (Ho) ranged between 0.05 and 0.43 (average 0.13) whereas both the expected heterozygosity (He) and polymorphic information content (PIC) ranged from 0.71 to 0.90 (average 0.83). Analysis of molecular variance (AMOVA) showed that 62% of the total genetic variation was found within accessions while the remaining 38% was found among accessions. Principal coordinate analysis (PCoA) indicated the presence of two groups. The two Kyrgyz cultivars were found apart from these groups. Cluster analysis generally confirmed the results of PCoA and also separated the Kyrgyz cultivars from the subcluster formed by Kyrgyz landraces and the subclusters formed by breeding lines from ICARDA along with landraces from Turkey and Spain. In addition, protein content and mineral concentration were determined. Protein content and mineral concentrations for Ca, S, Mg, P, K, Fe, Mn, Cu and Zn varied significantly among accessions. The results show that Kyrgyz germplasm provides a source of diversity for improvement of chickpea.

Amount and Size Distribution of Monomeric and Polymeric Proteins in the Grain of Organically Produced Wheat

ABSTRACT In the present study, we evaluated 444 organically grown wheat genotypes for the amount and size distribution of polymeric proteins by size-exclusion HPLC. The investigated genotypes were divided into six genotype groups—selection, spelt, old cultivar, primitive, landrace, and cultivar—and these were grown in four different locations, namely, Alnarp, Bohuslan, Gotland, and Uppsala in Sweden. The results showed that the percentage of unextractable polymeric proteins in total polymeric proteins (%UPP) and percentage of large unextractable polymeric proteins in total polymeric proteins were higher in the cultivar group as compared with the rest of the investigated genotype groups. The amounts of total extractable polymeric proteins (TOTE) and total unextractable polymeric proteins were low in cultivars and selections, respectively. Spring wheat grain was found to have a significantly higher amount of all protein fractions as compared with winter wheat. The genotype Kenya was found to belong to both ...

Breeding for improved stability in bread-making quality.

: Both genotype and environment influence the bread-making quality of wheat and a better stability in quality is desired. The reasons for variation and stability of wheat quality were investigated in Swedish and Baltic cultivars using Size Exclusion-High Performance Liquid Chromatography (SE-HPLC) and Reversed Phase-High Performance Liquid Chromatography (RP-HPLC). The results showed that; • Both grain protein concentration and gluten strength vary due to environmental influences. • Differences in gluten strength were due to differences in amount and size distribution of monomeric and polymeric proteins. • Differences in protein concentration were related to accumulation of glutenins and gliadins in the grain but not to differences in amount and size distribution of polymeric proteins. • Differences in cultivar stability for gluten strength were found, and correlated to stability in amount and size distribution of polymeric protein. • The ending of the grain-filling period varied in different grain positions in the spike, with the longest grain-filling time in the lower-mid part of the spike. • Variations in amount and size distribution of polymeric proteins at grain maturity were due to a change in extractability of polymeric and large monomeric proteins during grain development, indicating influences on disulphide bond formation. The amount and size distribution of polymeric proteins is thus of high importance in breeding cultivars of good and even quality between years. Environmentally influenced changes in amount and size distribution of polymeric proteins are due to changes in extractability of the polymeric proteins, indicating influences on disulphide bond formation. Successful breeding of more stable polymeric protein formation would lead to cultivars with more stable bread-making quality.