Diversity in agronomically important traits of wild emmer wheat, Triticum dicoccoides, the progenitor of most cultivated wheats, was examined in l60 genotypes representing 16 populations derived from a wide ecogeographical spectrum of climate, soil and water availability in Israel and Turkey. The analysis included 14 quantitative economic characters including heading date, culm length, biomass, grain yield and its components, and grain protein percentage.

The results led to two major conclusions: (i) agronomically important traits varied genetically: ecogeographic diversity in these traits is dramatically displayed when populations are grown in a relatively standardized environment; and (ii) genetic diversity is revealed not only between, but also within populations. Thus, genotypes excelling in some of these characters were found in several populations.

Infestations of Italian ryegrass are problematic in both conventional and organic wheat production systems. The development of wheat cultivars with superior competitive ability against Italian ryegrass could play a role in maintaining acceptable yields and suppressing weed populations. Research was conducted in North Carolina to identify indirect methods of selection for Italian ryegrass suppressive ability (hereafter referred to as weed suppressive ability) of winter wheat cultivars that correlate well with Italian ryegrass-to-wheat biomass ratios. Two winter wheat cultivars (Dyna-Gro Baldwin and Dyna-Gro Dominion) and one experimental wheat line (NC05-19684) with differing morphological traits were overseeded with varying densities of Italian ryegrass. Wheat height measured throughout the growing season in weed-free plots was strongly associated with weed suppressive ability, but high wheat tillering capacity had no significant effect on weed suppressive ability in the lines tested in this study. Italian ryegrass seed head density during grain fill was strongly correlated (r = 0.94) with Italian ryegrass-to-wheat biomass ratio, the generally accepted measure of weed suppressive ability. Visual estimates of percent Italian ryegrass biomass relative to the plot with the highest level of Italian ryegrass infestation in each replicate were also strongly correlated with weed suppressive ability at all growth stages, especially during heading (r = 0.87) (Zadoks growth stage [GS] 55). Measurements from nonimaging spectrophotometers and overhead photographs taken from tillering (Zadoks 23 to 25) to early dough development (Zadoks 80) were unreliable estimates of end-of-season Italian ryegrass-to-wheat biomass ratios because they failed to account for wheat cultivar differences in biomass, color, and growth habit. Italian ryegrass seed head density and visual estimates of Italian ryegrass biomass during grain fill are appropriate indirect methods of selection for weed suppressive ability in breeding programs.

The valorization of genetic diversities of major crops like wheat may help substantially to feed the world Population. Durum wheat genotypes consisting of 265 farmers’ varieties (FVs), which have been cultivated for many centuries in Ethiopia, as well as 24 improved varieties (IMVs) have been recently evaluated in northern Ethiopia. The evaluation has been carried out at two different locations for 2 consecutive years to verify the inherited diversity in FVs for important phenological and agronomic traits; with the intention to provide refined information to breeders and genebank managers. As a result of a careful evaluation, a very significant variation was observed between the FVs and IMVs. A large number of the former have demonstrated superior performance to the latter in terms of mean values of the major traits within the stipulated years and locations. The best performing FV has shown a gain of 20% grain yield over the best IMV. Multivariate analyses revealed that FVs displayed larger genetic diversity than in those IMVs. FVs could therefore be used as donor of useful alleles in durum wheat breeding for improvement of yield per se and other traits of agronomic and phenological importance. The identified stable superior FVs include: 8208, 226834A, 238567, 222426, 226282 could be best candidates for farmers in marginal environments. Genotypes that have shown stable performance for spatial variation such as 204493A, 214357 and 238567; and temporal variation such as 8208, 208479, 214357 and 226834A could be the best candidates for exploitation in future breeding programs.

Fe and Zn deficiency are widespread worldwide. As wheat is the primary food for the majority of the world people, producing wheat grains with high mineral content can ameliorate the problem of mineral hunger. However, the genetic variation available for breeders is limited. The aim of this study was to assess the genetic variation in grain Fe and Zn contents in 47 synthetic hexaploid wheats and to identify marker loci associated with Fe and Zn contents. We measured the grain Fe and Zn contents using inductively coupled plasma atomic emission spectroscopy and performed genotyping using SSR markers. The results showed considerable genetic variation for these minerals. We identified three lines with high Fe and Zn contents and six quantitative trait loci of which three were associated with Fe content and the other three with Zn content. The minerals showed positive phenotypic and genotypic correlation and high heritability (>60%). The ratio of the σ2g to the σ2g×e was ≥1 for the two mineral contents indicating that breeding for increasing mineral content within the synthetic lines is possible. The synthetic wheat lines identified in this study are valuable genetic resources, and can be utilized for breeding wheat cultivars with high mineral content.