Variability of in vitro culture response in wheat genotypes, genotype and environmental effects

The tissue culture response (TCR) of immature embryos, evaluated according to callus formation, percentage of regenerative green-spotted calli and the number of plants per embryo, was investigated in 96 wheat genotypes of worldwide origins. Immature embryos were collected 12-15 DAP from field-grown plants during three successive years 2003, 2004 and 2005. Year 2003 was with high air temperatures and tropical days during a period of vegetation, while the environmental conditions were more favorable for plant growth in the next two years, 2004 and 2005. Embryos were cultured on standard MS medium containing 2 mg l-1 2, 4-D. In all genotypes calli were efficiently induced, ranging from 36.7 to 100% (2003), 68.4 to 100% (2004), and 94.3 to 100% (2005). The calli occasionally formed green spots, but frequencies markedly differed among genotypes that varied from 0 to 72.5% (2003), 0 to 97.9% (2004), and 0 to 94.0% (2005). Coefficient of variation was highest in term of percent of regenerative calli (66.7%) following by a number of plants per embryo (35.6%) and callus formation (5.1%). Components of phenotypic variance showed that factor year (71.4%) had the highest impact on expression of callus formation, genetic factor (47,1%) on percentage of regenerative green-spotted calli and interaction year/genotype (30.3%) on number of plants per embryo. The results indicated factor genotype as the most important for determining regeneration potential in wheat

The effects of cytoplasmic male sterility and xenia on the chemical composition of maize grain

Sterile hybrids often outyield their fertile counterparts, especially if pollinated by a genetically unrelated pollinator. The combined effect of cms and xenia is referred to as the Plus-hybrid effect. The objective of this study was to determine the individual, as well as, combining effect of cms and xenia on the maize grain chemical composition. The percent of oil, protein and starch in the grain was also observed. Two sterile hybrids, their fertile counterparts and five fertile pollinator-hybrids were selected for the studies. The three-replicate trial set up according to the split-plot experimental design was performed at Zemun Polje in 2008. The obtained results show that the effects of cms on the oil percent was not significant in the studied hybrid ZP 341, while it increased at the significance level of P = 0.1 in the second observed hybrid ZP 360. The effect of this factor on the protein and starch percent was also significant (P = 0.01) in some hybrid combinations. Xenia effects on all three chemical parameters were significant (P = 0.01) in some hybrid combinations. The gained results indicate that the identification of a good combination of two hybrids, in which one would be a sterile female component, and the other a pollinator, would end up not only in the increased yield, but also in the improved maize grain quality

Assessing wheat performance using environmental information

The partial least squares (PLS) regression model was applied to wheat data set with objective to determining the most relevant environmental variables that explained biomass per plant and grain yield genotype x environment interaction (GEI) effects. The data set had 25 wheat genotypes (20 landraces + 5 cultivars) tested for 4 years in two different water regimes: rainfed and drought. Environmental variables such as maximum soil temperature at 5 cm in April and May, soil moisture in the top 75 cm in March, and sun hours per day in May accounted for a sizeable proportion of GEI for biomass per plant. Similar results were obtained for grain yield: maximum soil temperature at 5 cm in April, May and June, and sun hours per day in May were related to the factor that explained the largest portion (>38%) of the GEI. Generally, wheat landraces are able to better exploit environments with higher temperatures and lower water availability during vegetative growth (March-June) than cultivars

Grain yield, agronomic traits, and protein content of two- and six-row barley genotypes under terminal drought conditions

Small grain cereals in lower latitude areas usually mature under terminal drought conditions that affect their agronomic performance. An experiment was conducted to compare agronomic traits, grain yield, and protein content under control and terminal drought conditions of 15 two-row and 10 six-row barley (Hordeum vulgare L.) genotypes. The experiment was set up at two locations for two growing seasons (2011, 2012) and two treatments. One treatment was terminal drought (D) simulated by the mechanical removal of all leaf blades 7 d after the heading of each genotype, and a control (C) treatment in which plants were left intact. On average, defoliation caused a greater reduction in grain yield and protein content of the six-row genotypes (37.6% and 12.3%, respectively) than the two-row genotypes (28.8% and 7.1%, respectively). On the other hand, test weight of six-row genotypes showed better tolerance to terminal drought. According to the multivariate function analysis, the genotypes of both types of barley with a high test weight, a longer uppermost internode, and a longer grain filling period had high protein content under terminal drought stress. In contrast to six-row genotypes, it is possible to breed two-row genotypes that not only have high grain yield but also high protein content under both optimal and drought stress conditions

Expected genetic advance and stability of phytic acid and antioxidants content in bread and durum wheat

Fifteen genotypes of bread wheat (Triticum aestivum L.) and fifteen genotypes of durum wheat (Triticum durum Desf.) were evaluated in the multi-environment trial during 2010-11. and 2011-12 vegetation seasons to investigate components of variance, heritability in a broad sense (h(2)), expected genetic advance (GA), and stability of phytic acid (PA), inorganic phosphorus (P-i), phytic phosphorus (P-p)/P-i relation, yellow pigment (YP), water soluble phenolics (WSPH) and free protein sulfhydryl groups (PSH) content. The field trials were carried out at three locations in Serbia, as randomized complete block design with four replications. The genetic component of variance (sigma(2)(g)) predominated the genotype x environment interaction (sigma(2)(ge)) component for: P-i in bread wheat (3.0 times higher), P-p/P-i in bread wheat (2.1 times higher) and in durum wheat (1.2 times higher), YP content in bread wheat (2.2 times higher) and in durum wheat (1.7 times higher), and WSPH content in bread wheat (1.4 times higher). The relation sigma(2)(g)/sigma(2)(ge) for P-i content in durum wheat was equal to one. The sigma(2)(ge) prevailed sigma(2)(g) for: PA in bread wheat (1.7 times higher) and in durum wheat (5.7 times higher), PSH in durum wheat (3.7 times higher), and WSPH in durum wheat (5.2 times higher). High h(2) coupled with high expected genetic advance as percent of mean (GAM) were observed for: P-i (93.7% and 26.1%, respectively) in bread wheat, P-p/P-i relation in bread wheat (92.4% and 20.7%, respectively) and in durum wheat (87.2% and 20.8%, respectively), YP content in bread wheat (92.6% and 28.0%, respectively) and in durum wheat (90.7% and 28.1%, respectively), and WSPH content (88.9% and 25.8%, respectively) in bread wheat. PA content in bread and durum wheat had medium to medium high h(2) (50.5% and 77.9%, respectively), and low expected GAM (9.9% and 3.7%, respectively). GGE biplots with average-environment coordination (AEC) indicated less stability of durum wheat for PA, WSPH and PSH content

Oplemenjivanje pšenice na nizak sadržaj fitinske kiseline - stanje i perspektive

Interest in wheat breeding for low phytic acid content arised from its roll as antinutrient factor which chelates mineral elements (Ca, Zn, Fe, Mn, Cu and P), leading to their inadequate use. Excretion of unused P in phytic acid complex through non-ruminant animals such as poultry, swine and fish causes water eutrophication. Numerous indirect methods (e.g. spectrophotometric) and direct methods (HPLC - High Performance Liquid Chromatography) were developed for fast and accurate phytic acid determination in wheat. It typically represents 50-85% of seed total phosphorus and one to several percents of dry seed weight. Phytic acid content and phytate phosphorus genetic variability have been determined for wheat cultivars and lines under different environmental conditions. Wheat mutant (Triticum aestivum L) for low phytic acid content Js-12-LPA was created through breeding efforts.Potreba za oplemenjivanjem pšenice na nizak sadržaj fitinske kiseline proistekla je iz njene uloge antinutritivnog faktora koji vezujući mineralne elemente (Ca, Zn, Fe, Mn, Cu, kao i P) dovodi do njihovog nedovoljnog iskorišćavanja. Neiskorišćeni fosfor u kompleksu sa fitinskom kiselinom se preko lanca ishrane nepreživara (živina, svinje, ribe) izlučuje u spoljašnju sredinu i uzrokuje zagađivanje vodenih ekosistema. Razvijene su brojne indirektne (spektrofotometrijske) i direktne (HPLC - High Performance Liquid Chromatography) metode za brzo i pouzdano utvrđivanje sadržaja fitinske kiseline u zrnu pšenice. Brojna istraživanja u svetu su pokazala da se sadržaj fitinske kiseline kreće od jedan do nekoliko procenata suve mase semena i 50% do 85% ukupnog fosfora u semenu. Utvrđena je značajna genetička varijabilnost sadržaja fitinske kiseline i fitatnog fosfora u zrnu sorata i linija pšenice u različitim uslovima spoljašnje sredine. Oplemenjivanjem je dobijen i mutant pšenice (Triticum aestivum L) Js-12-LPA, za osobinu niskog sadržaja fitinske kiseline (Low phytic acid)

Contribution of Agro-Physiological and Morpho-Anatomical Traits to Grain Yield of Wheat Genotypes under Post-Anthesis Stress Induced by Defoliation

Post-anthesis drought affects wheat production worldwide, primarily through the limitation of grain filling. The enhanced remobilization of stem reserves induced by drought can provide considerable carbon sources for grain filling. The aim of this study, which was part of an ongoing wheat-breeding program targeting drought tolerance, was to assess the ability of 20 contrasting common wheat genotypes (2 cultivars, 8 F6:7 families (FAM), and 10 parent genotypes (PAR) used to make the families) to remobilize stem dry matter under water-stressed conditions simulated via defoliation 10 days after anthesis, and to estimate the contribution of stem dry matter remobilization to grain weight. In two-year field trials, the genotypes were scored for agro-physiological and peduncle morpho-anatomical traits. Stem reserve contribution to grain weight per spike was significantly enhanced in defoliated plants but did not differ amongst the groups of genotypes. F6:7 families had higher grain-filling rate and 1000-grain weight but without improvement in grain weight per spike under defoliation compared with parental groups. The total area of chlorenchyma, phloem-area-related traits, and stem reserve contribution to grain weight were positively associated with grain weight per spike under defoliation, whilst in both treatments, the grain-filling rate was determined by stem height. These results imply that the grain-filling rate is a trait desirable for drought tolerance that can be improved during the breeding process. © 2023 by the authors

Effects of climatic factors on grain vitreousness stability and heritability in durum wheat

Modern durum wheat breeding programs are becoming more oriented toward creation of not only high-yield cultivars but also high quality, with good stability for the trait of interest. Vitreousness of grain is associated with semolina granulation, color, and protein content; it is regarded as one of the most important characteristics in the grading industry, affecting the commercial value of the commodity. A set of 15 winter and facultative durum wheat genotypes was tested for grain vitreousness across 6 environments for 2 consecutive years. Three-way analysis of variance showed that genotype, location, and year contributed 4.1%, 20.6%, and 42.2% to the total sum of squares, respectively. Interaction terms, including genotype, contributed 6.1% to the total sum of squares, and location x year contributed 27.0%. Stability of grain vitreousness for the examined breeding lines and cultivars of durum wheat was shown by the site's regression. Broad-sense heritability of grain vitreousness was estimated to be 71%. Climatic variables were used for factorial regression modeling, and most of the interaction term for grain vitreousness was explained by mean temperatures in June (54.4%) and April (14.2%), and precipitation (14.4%) and sunshine hours (14.3%) in March. During the grain filling and grain ripening stages, the most influential climatic variables in explaining interaction were maximum temperature (43.4%), precipitation (30.9%), and sunshine hours (5.6%)

Triticum aestivum ir T. durum genetiniai parametrai kokybės technologinėms savybėms Serbijoje

Proteins are important in determining the nutritional value of wheat, and among them gluten determines the baking quality of bread wheat and pasta-making technological properties of wheat. By assessing genetic parameters of wheat quality traits, it is possible to elucidate potential for improvement. The plant material consisted of 30 genotypes of bread and durum wheat of worldwide origin. The trials were sown at three locations in Serbia during two vegetation seasons 2010-2011 and 2011-2012. Protein content, wet gluten content, Zeleny sedimentation volume and deformation energy were determined by near infrared spectrometry. The objectives of this investigation were to assess: i) variability, components of variance, heritability in a broad sense (hb2)expected genetic advance for protein content, wet gluten content, Zeleny sedimentation volume and deformation energy; ii) associations between agronomic characteristics and protein content, wet gluten content, Zeleny sedimentation volume and deformation energy in order to determine indirect selection feasibility. In durum wheat, the highest coefficients of genetic and phenotypic variation (CVg and CVph) were recorded for deformation energy in bread wheat (18% and 18.4%, respectively), whereas the lowest values of 4.1% and 4.6% were shown for protein content. The relation genetic component of variance (σg2)/component of variance due to genotype × environment interaction (σge2) < 1 was observed for protein content (3.2), wet gluten content (2.9) and deformation energy (3.9), and equal to one for Zeleny sedimentation volume, in bread wheat. In durum wheat, σge2/σg2< 1 was detected for protein content (1.4), wet gluten content (1.5), Zeleny sedimentation volume (2.1) and deformation energy (1.4). Considering very high and high hb2 observed for deformation energy and Zeleny sedimentation volume (95.8% and 86.2%, respectively) in bread wheat, coupled with high genetic advance (36.3% and 28.1%, respectively), success from classical breeding can be anticipated. Grain thickness was strongly associated with Zeleny sedimentation volume, and to a lesser extent with protein content, wet gluten content and deformation energy in bread and durum wheat, and along with grain vitreousness in durum wheat, can serve for indirect selection