Iron and zinc grain density in common wheat grown in Central Asia

Sixty-six spring and winter common wheat genotypes from Central Asian breeding programs were evaluated for grain concentrations of iron (Fe) and zinc (Zn). Iron showed large variation among genotypes, ranging from 25 mg kg1 to 56 mg kg1 (mean 38 mg kg1). Similarly, Zn concentration varied among genotypes, ranging between 20 mg kg1 and 39 mg kg1 (mean 28 mg kg1). Spring wheat cultivars possessed higher Fe-grain concentrations than winter wheats. By contrast, winter wheats showed higher Zn-grain concentrations than spring genotypes. Within spring wheat, a strongly significant positive correlation was found between Fe and Zn. Grain protein content was also significantly (P < 0.001) correlated with grain Zn and Fe content. There were strong significantly negative correlations between Fe and plant height, and Fe and glutenin content. Similar correlation coefficients were found for Zn. In winter wheat, significant positive correlations were found between Fe and Zn, and between Zn and sulfur (S). Manganese (Mn) and phosphorus (P) were negatively correlated with both Fe and Zn. The additive main effects and multiplicative interactions (AMMI) analysis of genotype × environment interactions for grain Fe and Zn concentrations showed that genotype effects largely controlled Fe concentration, whereas Zn concentration was almost totally dependent on location effects. Spring wheat genotypes Lutescens 574, and Eritrospermum 78; and winter wheat genotypes Navruz, NA160/HEINEVII/BUC/3/F59.71//GHK, Tacika, DUCULA//VEE/MYNA, and JUP/4/CLLF/3/II14.53/ODIN//CI13431/WA00477, are promising materials for increasing Fe and Zn concentrations in the grain, as well as enhancing the concentration of promoters of Zn bioavailability, such as S-containing amino acids

Genetic gains for grain yield in high latitude spring wheat grown in Western Siberia in 1900-2008

Short season high latitude (50 degrees N-56 degrees N) spring wheat (Triticum aestivum L) is grown on approximately 7 million ha in Western Siberia with average yield of 1.5-2.0 t/ha. A historical set of 47 varieties developed and grown in the region between 1900 and 2000 was evaluated at a trial in Siberian Research Institute of Agriculture (Omsk) in 2002-2008. The genetic gains for grain yield and associated changes in agronomic traits were analyzed for three maturity groups (early, medium and late) and four breeding periods (before 1930, 1950-1975, 1976-1985 and after 1985). The overall yield was 3.71 t/ha for modern varieties versus 2.18 t/ha for old varieties representing 0.7% increase per year in the course of 100 years. The genetic gains between the breeding periods indicated that the rate of progress for the early and medium maturity groups was more or less comparable from one breeding period to the other. For the late maturity group there was an obvious and sharp decline in genetic gain with time. Modern varieties were also characterized by average response to environmental mean and good grain yield stability evaluated according to Eberhart and Russell (1966). Thousand kernel weight and number of grains per unit area were linearly correlated with grain yield and genetic gain over time suggested their importance for breeding progress. Resistance to leaf rust in some modern varieties sustained and contributed to stability of genetic gains. The yield increase over time was not associated with plant height reduction and incorporation of Rht genes. The maturity range of the newer varieties is narrower compared to old germplasm as they tend to belong to medium maturity group. Translocation 1B.1R had limited contribution to Western Siberian germplasm being observed in only three varieties. The increase in adaptation, yield potential and its stability has been reached due to gradual accumulation of favorable genes through diverse crosses, robust selection and testing system. Resistance to leaf rust and other prevalent pathogens is of paramount importance for future progress

10681_2006_9321_Author.pdf

Abstract Sixty-six spring and winter common 11 wheat genotypes from Central Asian breeding 12 programs were evaluated for grain concentrations 13 of iron (Fe

Phenotypic correlations, G x E interactions and broad sense heritability analysis of grain and flour quality characteristics in high latitude spring bread wheats from Kazakhstan and Siberia

Grain and flour samples of 42 high latitude spring bread wheat genotypes from Kazakhstan and Siberia evaluated in a multi-location trial were analyzed for grain concentrations of protein, zinc (Zn) and iron (Fe), as well as flour quality characteristics. The genotypes showed high grain protein concentrations (14-19%), but low dough strength was a common feature for most of them. Significant positive correlations were found between grain protein and flour protein, gluten, gliadin, gli/glu ratio, Zn, and Fe contents. Grain protein was also correlated positively with hardness, sedimentation, farinograph dough development time (DDT), stability time and ash content. Grain Fe concentration was positively associated with sedimentation, stability time, water absorption and valorimeter value, suggesting that improvements in micronutrient concentrations in the grain parallels enhancement in gluten strength. Interestingly, glutenin content correlated negatively with the concentrations of grain and flour protein, gluten, and minerals; and also with gluten deformation index (IDK), DDT, and stability time. Conversely, gliadin content showed strong positive correlations with the concentrations of grain and flour protein, gluten, and minerals. Gliadin also correlated positively, but in lesser magnitude, with DDT, stability time and IDK. Environment and GxE interaction were important sources of variation for some quality characteristics. This was reflected in the low broad sense heritability (H) values for traits related to flour strength, such as sedimentation, IDK, stability time and gliadin content. Breeding strategies, including three testing locations at the advanced selection stages, are adequate for the enhancement of most of the quality traits, but faster improvement in flour strength could be achieved with a larger number of locations