Diego Baretta

Conteúdo de β-glucana em cultivares de aveia-branca cultivadas em diferentes ambientes

Abstract – The objective of this work was to characterize white oat cultivars as to β‑glucan content in grains, to verify its relationship with grain and industrial yield, and to defineadaptability and phenotypic stability parameters for these characters. In the 2007 and 2008 seasons, 15 white oat cultivars were grown in Augusto Pestana, Capao do Leao and Passo Fundo municipalities, state of Rio Grande do Sul, Brazil. It was used a randomized complete block design, with four replicates and 3-m 2 plots. Genotype performance varied according to the region and year of cultivation in relation to β‑glucan content in the grain. The genotypes Barbarasul, Brisasul, UFRGS 19, UPFA 22, URS 20, URS 22 and URS Guapa had an ideal biotype, comprising high mean β‑glucan content, wide adaptability and phenotypic stability. Significantcorrelations are observed between β‑glucan content and grain and industrial yield.Index terms: Avena sativa , adaptability, functional foods, stability, genotype x environment interaction, grain quality.

Correlações canônicas entre caracteres morfológicos e componentes de produção em trigo de duplo propósito

The objective of this work was to identify canonical correlations between morphological traits and yield components in dual‑purpose wheat, under different cutting managements. The experiments were carried out in 2013 and 2014, under a complete block design, in a factorial arrangement with five genotypes (BRS Taruma, BRS Umbu, BRS Figueira, BRS Guatambu, and BRS 277), four cutting managements (no cuts, one cut, two cuts, and three cuts), and three replicates. The canonical groups were established between morphological traits (group 1) and yield components (group 2). In group 1, number of tillers, diameter of the main stem and of the tillers, and number of fertile tillers were evaluated; in group 2, the number of grains per spike and of spikes per square meter, the mass of grains per spike and of a thousand grains, grain yield, and hectoliter weight were evaluated. The correlation between groups 1 and 2 depends on the adopted cutting management. The diameter of the main stem (in the managements without and with one cut), tiller diameter (two cuts), and the total number of tillers and of fertile tillers per plant (three cuts) should be prioritized for selection of superior genotypes as to grain yield and hectoliter weight.

Partial diallel analysis among maize lines for characteristics related to the tassel and the productivity

Diallel crosses are important to the prediction of the best combinations among different heterotic groups of maize lines. The work objective was to estimate the combining ability among inbred lines from two heterotic groups to predict the best combinations in traits related to tassel and grain yield, conducted in five environments in the southern region. The inbred lines of the two heterotic groups are from the company KSP seeds. The tests were conducted based on crosses with partial diallel, using 15 female parents and male parents 8, 2011/2012 agricultural harvest in five environments in randomized blocks design with three replications. The variables analyzed were tassel length (TL), distance from the last node to the first branch of the tassel (DLN), distance from the flag leaf to the first branch of the tassel (DFL), number of tassel branches (NB), mass thousand grains (MTG) and grains yield (GY). The data were submitted the individual and joint variance analysis, after were realized analyze partial diallel analysis. The additive effects were more important for group II, already to the group I the non-additive effects were more pronounced, for the traits tassel and of yield. The GCA (group I) of lines inbred 15; 4 and 3-4 (group II) are favorable for increasing the grains yield. The crosses promising tassel traits been: 1-3, 2-4, 3-3, 4-4, 7-3, 8-3, 9-3, 10-3, 10-4, 11-4, 12-4, 14-3 and 15-4. The crosses promising increasing of grains yield been: 1-1, 1-4, 2-3, 3-1, 3-4, 4-3, 4-6, 4-7, 5-3, 5-4, 6-3, 6-4, 7-4, 8-4, 9-4, 10-5, 11-3, 12-3, 14-4, 15-2, 15-5 e 15-8. Key words: Combinatorial capacity, genic effect, diallel crosses, grain yield.

Estimates of genetic parameters and genotypic values prediction in maize landrace populations by REML/BLUP procedure

The REML/BLUP statistics are analyses that can be used as selective criteria in the routine of maize breeding programs. The present study aims to determine the genetic potential in crosses of landrace populations applying the REML/BLUP methodology, and to identify populations for the synthesis of new populations and intrapopulation selection for family farming systems, as well as genetic constitutions for use in maize breeding programs. Nine top cross hybrids obtained in the 2012/2013 harvest were evaluated along with their testator, the landraces used as parents, and four commercial hybrids, in a randomized block design, with information taken from the average of each plot. The evaluated traits were: leaf angle, number of ramifications of the tassel, spike insertion height, plant height, spike diameter, number of grains per spike, mass of grains per spike, spike mass, spike length, prolificity, mass of one hundred grains, and grain yield per plot. The data were analyzed using the Selegen-REML/BLUP software. The top cross hybrids Cateto Branco x Planalto, Amarelão x Planalto and the population Cateto Branco are ranked among the ten best crosses, simultaneously, for the traits: leaf angle, number of ramifications of the tassel, spike insertion height, and plant height (Cateto Branco x Planalto), and leaf angle, spike insertion height, and plant height (Amarelão x Planalto and Cateto Branco). The top cross hybrids Criolão x Planalto, Branco 8 Carreiras x Planalto, Caiano Rajado x Planalto, Amarelão x Planalto, Branco Roxo Índio x Planalto stand out for their high genotypic value of the individual BLUP mean components among the ten best genotypes for grain yield, and by combining three or more traits of interest together, being, for effects of selection, the most indicated.

Identification of variability for agronomically important traits in rice mutant families

The increase of yield potential in new rice (Oryza sativa L.) varieties has been a major challenge for genetic improvement. The generation of mutants, followed by their characterization, constitutes a great possibility to isolate and select genes and genotypes that present agronomic traits of interest. This study aimed to evaluate the effect of chemical mutagen ethyl methane sulphonate (EMS) on agronomic traits in 340 M3 families of rice derived from BRS Querencia cultivar. Seeds from each family and the original genotype BRS Querencia were sown in the experimental field, and the characters main panicle length, main panicle weight, main panicle grain weight, flag leaf width and plant height were evaluated. Data were subjected to analysis of variance (p ≤ 0.05), and a comparison of means was carried out by Dunnetts test at 5% significance. The results show that there is genetic variability among the mutant families, suggesting that the mutagen EMS at 1.5% is effective for generating mutants for all assessed traits. Among the characters, plant height was the most affected by the mutagen, which provided an increase in the character. For the main panicle length character, seven families showed means above the control; for main panicle weight and grain weight, four and six mutant families were observed, respectively, with a superior performance in comparison to the control.

Tolerance to preharvest sprouting and yield of wheat genotypes from different breeding programs

The objective of this work was to characterize the performance of elite wheat genotypes from different Brazilian breeding programs for traits associated with grain yield and preharvest sprouting. The study was conducted in 2010 and 2011 in the municipality of Capao do Leao, in the state of Rio Grande do Sul, Brazil, in a randomized complete block design with three replicates. Thirty‑three wheat genotypes were evaluated for traits related to preharvest sprouting and grain yield. The estimate of genetic distance was used to predict potential combinations for selection of plants with high grain yield and tolerance to preharvest sprouting. The combined analysis of sprouted grains and falling number shows that the TBIO Alvorada, TBIO Mestre, Frontana, Fundacep Raizes, Fundacep Cristalino, and BRS Guamirim genotypes are tolerant to preharvest sprouting. Combinations of TBIO Alvorada and TBIO Mestre with Fundacep Cristalino show high potential for recovering superior genotypes for high grain yield and tolerance to preharvest sprouting.

Variabilidade genética para características agronômicas superiores em cruzamentos biparentais de aveia preta

abstract GENETIC VARIABILITY FOR TOP AGRONOMIC CHARACTERISTICS IN BIPARENTAL CROSSES OF BLACK OATSThe area sown to black oat in Brazil has experienced a dramatic growth as a consequence of the expansion of minimum tillage, crop rotations and crop-livestock systems. This growth was not accompanied by research work providing data on the relevant agronomic traits from this forage grass, which would eventually lead to the creation of new varieties meeting the growers’ demands. This work evaluated traits related to forage production and seed dormancy in black oat populations originating from artificial breeding between pure lines derived from the “Preta Comum” variety and commercial varieties from this species. Two experiments were carried out during the winter of 2008, at the Capao do Leao, Rio Grande do Sul State, one to assess forage production traits and the second to measure seed traits such as yield and dormancy levels. The results showed that artificial breeding enhanced genetic variability through improvement on the expression of forage traits, seed yield and dormancy levels. In relation to the former, plant stand was highly associated to dry matter production during the early stages of seedling development and establishment, while tiller production remained the major component explaining biomass production later stages of forage production. Artificial breeding produced large differences on seed-related traits such as yield and dormancy level, suggesting the existence of adequate levels of variability for these traits among the parent lines.