Evaluation of grain characteristics of domestic wheat (Triticum aestivum L.) obsolete cultivars and landraces

The research on wheat accessions was carried out in order to evaluate their grain characteristics. Experiment was set in the agro-ecological conditions of Banja Luka in two experimental years (2015/16 and 2016/17). Ten obsolete wheat cultivars (Brkulja, Ličanka, Partizanka, Vuka, Talijanka, Šiđanka, Orašanka, Lozničanka, Dokučajevskaja and Nemcitaevskaja) and two landraces (Podrašnica and Previja) were used. Following grain characteristics were evaluated: grain length (mm), grain width (mm), grain thickness (mm), grain volume (mm3), grain surface area (mm2), thousand grain weight (g) and grain protein content (%). Significant interactions were found for most of these traits. The relationship between traits was established by correlation analysis. In this study genotypes Brkulja and Šiđanka showed promising for most of the grain characteristics, while Vuka and Partizanka obtained the highest grain protein content.

Higher Effectiveness of New Common Bean (Phaseolus vulgaris L.) Germplasm Acquisition by Collecting Expeditions Associated with Molecular Analyses

A remarkable portion of crop genetic diversity is represented by landraces and obsolete cultivars, that have not yet been integrated into the collections of genetic resources in genebanks. Fortunately, they are still maintained by small farmers in rural areas. Their acquisition is an important goal for collecting expeditions, followed by the evaluation of their genetic background. Molecular markers are powerful tools to evaluate the effectiveness of acquisition of new genetic variants. This approach was used for common bean landraces, that were collected through expeditions in the Slovak and Ukrainian Carpathians. In this study, microsatellite markers, developed from expressed sequence tags, were used for genotyping the collected materials. The sub-population of collected landraces contained higher total and average number of different alleles in comparison to equally large sub-populations of already-maintained cultivars. The same was true for the Shannon’s information index, observed heterozygosity, and expected heterozygosity. Both sub-populations showed the presence of private alleles: Average values of 0.500 and 0.833 private alleles per genotype were detected in landraces, and cultivars, respectively. Obtained results emphasized the importance of collecting expeditions to specific regions where landraces are cultivated, even at the present time. The effectiveness of the acquisition of new genetic variability can be determined by molecular tools, as confirmed by microsatellite markers in this study.

Earliness, spike productivity and protein content in European winter wheat landraces and obsolete cultivars

European winter wheat landraces and obsolete cultivars (121 accessions in set I and 101 accessions in set II) with modern check cultivars were evaluated in three-year field trials. Increased spike productivity in modern cultivars could be attributed mainly to increased number of grains in spikelet and increased HI, whereas TGW has marginal effect. Old cultivars had on average by 2–3% higher crude protein content in grain than modern ones. Among selected 10 characters, relatively wide diversity (C.V. 11–20%) has been estimated in spike length and characters of spike productivity (except of grain weight with C.V. close to 9%). It was difficult to distinguish the cultivars according to the country of origin, however, earliness and lower spike productivity seems to be characteristic for South-East origin whereas cultivars from North-West Europe showed opposite characters. Correlation analyses showed close relations between earliness in heading and in maturity and negative relation between late heading and grain filling period, which was positively correlated with TGW and HI (r = 0.26 to 0.38). Number of grains in spikelets was highly correlated with spike productivity and HI (r = 0.62 to 0.69) whereas relations between these two characters and TGW were lower (r = 0.20 to 0.51). Spike productivity characters, except of TGW, are in negative correlation with crude protein content in grain (r = –0.34 to –0.50). Regression analyses confirmed that main determining character for the spike productivity is number of kernels in spikelet (about 40% of variation) while effects of TGW are about half-size. Crude protein content was positively affected by plant height (15–30% of variation) impact of grain weight per spike was lower (14–17% of variation) and negative. Potentially valuable donors of earliness and longer grain filling period were identified for further studies and/or utilization in breeding programs. As especially valuable character can be considered very high crude protein content (around 18% in cvs Berg-land, Ukrajinka, Sippbachzeller, Innichen Nr. 25001 and Barbu du Finistre). High crude protein content combined with relatively good spike productivity and/or long grain filling period or earliness was found in cvs Visperterminen 640 E, Hatvan, Szekacz 1242, Berchtesgardener Vogel, Ble du Lot and Barbu du Finistere.

How can wheat landraces contribute to present breeding?

Two sets of winter wheat landraces and obsolete cultivars were studied in three-year field experiments, and compared with 3 modern control cultivars. The higher spike productivity in modern cultivars could mainly be attributed to an increased number of grains in a spikelet and harvest index (HI), whereas thousand grain weight (TGW) has only a slight effect. Landraces and old cultivars proved to have a higher content of crude protein. Spike productivity characteristics, except for TGW, showed a negative correlation with the crude protein content in the grain. The number of kernels in a spikelet strongly affected the spike’s productivity, whereas the TGW has only half the effect. The mean yield of four modern cultivars was 51% higher than the mean yield of 31 landraces and obsolete cultivars. Regression analysis proved the much stronger response of modern cultivars to environment (<I>b </I>= 1.63), then was the response of old cultivars (<I>b </I>= 0.87). Different responses to environments were found within the set of 31 landraces, as well. We could also identify potentially valuable donors of earliness and winter hardiness among the old cultivars. High crude protein content (up to 18%), and other valuable quality characteristics, were rather frequent. In both sets, HMW <I>Glu</I>-subunits were described, and we have additionally studied 67 selected lines. Among them, 10 lines showed the crude protein content of 17.5% to 18.3% (where the gluten index and Zeleny test varied from 28.5 to 54.0 and 36.8 to 61.7, respectively). High values of all quality characteristics showed lines gained from the cultivars Mindeszentpusztai (HUN), Szekacz 19 (HUN), Bartweizen linie a (AUT), Viglašská červenoklasá (CZE), as well as some others.

Landraces and obsolete cultivars of minor wheat species in the czech collection of wheat genetic resources

The proportions of landraces in the Czech collection of wheat genetic resources significantly differentiates among wheat species, 4.2% in bread, 77.6% in emmer, and 80.0% in the einkorn wheat collections. A set of 10 selected emmer wheat landraces has been characterized by high molecular weight glutenin subunits (HMW-GSs). They were evaluated for 3 years in field trials, and described by grain quality parameters. Emmer wheat accessions differ considerably in the polymorphisms of HMW-GSs. Out of the total of 10 studied emmer wheat landraces, 5 accessions appeared to be homogeneous in the electrophoretic patterns of HMW-GSs; they were formed by a single glutenin line. Much higher crude protein content was detected in all of the emmer wheat accessions, in comparison with the control bread wheat cultivar. The proportion of this important component varied between 15.5% and 22.2%. On the other hand, SDS sedimentation, an important parameter of bread making quality, was very low (1.2–4.4 ml); and a similar situation has been recorded in the gluten index. Based on such results, the emmer wheat landraces can be considered potentially more suitable for other purposes than for the preparation of bread (<I>e.g. </I>for different grain mixtures, purée, etc.).

Results of projects on collecting, mapping, monitoring, and conserving of plant genetic resources 1990–2008

&nbsp;Old landraces and obsolete cultivars represent a national heritage that must be conserved for future generations. Similarly, crop wild relatives (CWR) are a valuable gene pool for plant breeding or for direct introduction as a new crop. These materials have been mapped, collected, evaluated, regenerated, and conserved in the Gene Bank. In total, 3726 seed and vegetative samples have been collected in the Czech Republic, as well as 1582 abroad (in Slovakia, Poland and Austria) during cross-border cooperation projects. All collecting sites (over 1000) were located by GPS and plotted using the Geobaze Professional 2.8 mapping software. Altogether, 688 samples were declared as a national collection, and 627 seed accessions were conserved in the Gene Bank. In addition, 842 accessions of fruits were recommended for <I>in situ </I>conservation. Selected species of the families <I>Poaceae, Fabaceae, </I>and <I>Alliaceae</I>, which are rare or threatened in the Czech Republic, have been monitored <I>in situ </I>for 3–5 years. Two sites were suggested for protection as new protected areas.

Seed rates for soft white winter wheat in southwestern Ontario

This study was undertaken to determine the optimum seed rate for soft white winter wheat (Triticum aestivum L.) cultivars currently grown in southwestern Ontario (> 2900 corn heat units) where 65% of Ontario’s wheat is grown. The currently recommended density of 240–400 plants m−2 was determined using obsolete cultivars. Two popular cultivars, Harus, which tillers abundantly, and Rebecca, which tillers less, were grown from 100 to 600 seeds m−2 in increments of 100. The optimum seed rate for grain yield was 435 seeds m−2. This rate appears to be suitable for a range of genotypes adapted to southwestern Ontario. There was no interaction for yield among cultivars, years and locations. Yield was not related to tillering capacity, as the lower the plant density the more seeds there were per head. Key words: Wheat (winter), seed rate, tillering