Alan Junior de Pelegrin

Desempenho fisiológico de sementes olerícolas em diferentes tempos de hidrocondicionamento

The production of high quality physiological seed is a major challenge for seed producers. In the search for lower cost conditioners arises the possibility of using hydropriming, which consists of a controlled hydration of seeds. The aim of this study was to evaluate the efficiency of this technique on lettuce, cabbage and tomato seeds, submitted to different times of imbibition in water. Eight periods of hydropriming in three vegetable crops were used, wherein for each of these was conducted a separate experiment. For lettuce and cabbage, periods tested were 0, 5, 10, 15, 20, 25, 30 and 35 hours and for tomato were of the periods 0, 24, 48, 72, 96, 120, 144 and 168 hours. The seeds of each treatment were submitted to the germination test and vigor to determine the physiological potential. For the tomato crop, the best answers to the average time of germination, emergence speed index and emergency field were found 72 hours of imbibition. As for the cabbage crop the best answers to these variables were obtained with 20 hours of imbibition. Lettuce did not respond positively to the imbibition times.

Combination Capacity and Association Among Traits of Grain Yield in Wheat (Triticum aestivum L.): A Review

Grain yield is a complex quantitative trait, because its expression is associated to the large number of genes with small effect. In addition, there is interaction among different yield components and environment effect, making difficult the direct selection of genotypes. The most viable alternative for wheat breeding programs, an autogamous plant, is use artificial crosses in order to obtain superior genotypes. Hybridization after use of successive self-fertilizations results in segregating populations, which reveal the genetic variability, especially when the parents are genetically different. Therefore, it is important to know genetic relationships between crosses, which will serve as reference for decision making in the choice of combinations. Therefore, general combining ability (GCA) and specific combining ability (SCA) are used, which facilitate choice of the best parents to compose crossover block. In addition to these parameters, path analysis can be used to determine importance of primary and secondary traits and to guide indirect selection of promising genotypes by means of interest traits.

Parcelamento e fontes de nitrogênio na qualidade fisiológica de sementes de trigo

Diferentes fontes e manejos parcelados de nitrogenio podem aumentar a disponibilidade, a absorcao e a assimilacao deste nutriente pelas plantas, favorecendo o acumulo de N nos graos. No entanto, pouco se sabe sobre a influencia destes fatores na qualidade fisiologica de sementes de trigo (Triticum aestivum L). Dentro deste contexto, o objetivo deste trabalho foi avaliar a resposta de diferentes fontes e parcelamentos de nitrogenio aplicado em cobertura na qualidade fisiologica das sementes de trigo. O experimento foi conduzido em delineamento de blocos completos casualizados em esquema de parcelas subdivididas com tres cultivares de trigo (TBIO Mestre, TBIO Iguacu e Quartzo), tres fontes de nitrogenio (ureia, nitrato de amonio e ureia liquida) aplicadas em cinco parcelamentos (I: afilhamento; II: afilhamento e emborrachamento; III: afilhamento e florescimento; IV: emborrachamento e florescimento e V: afilhamento, emborrachamento e florescimento). O parcelamento do nitrogenio entre os estadios de emborrachamento e florescimento resulta em sementes com maior qualidade fisiologica, pois incrementa o percentual de germinacao em 4% e influencia positivamente os caracteres na primeira contagem de germinacao, comprimento de parte aerea, e massa seca de plântula. As fontes de nitrogenio, nitrato de amonia e a ureia fonte liquida, se equiparam com a ureia em relacao ao efeito na qualidade fisiologica das sementes, sendo alternativas interessantes para reduzir o custo de producao. As cultivares TBIO Mestre e Quartzo evidenciaram sementes com maior qualidade fisiologica, em funcao do maior comprimento de radicula e percentual de germinacao.

Heterosis and genetics parameters for yield and nutritional components in half-sibling maize progenies

The growing demand for maize creates a challenge to breeders, requiring the development of higher yielding and higher quality genotypes. The objective of this work was to estimate the most relevant heterosis, variance components and genetic parameters, and to use a multivariate approach to define narrow sense heritability profiles for yield and nutritional components in half-sib maize progenies. The experimental design used was random blocks, with a male parent (hybrid tester), five inbred lines (S5) as maternal parents and the progenies (hybrid Top Cross), totalizing 11 maize genotypes arranged in six replicates. Agronomic and nutritional characters were evaluated. Half-sibling progenies reveal greater additive genetic contribution to phenotypic expression through grain width and thickness, iron content, total flavonoids and carotenoids, soluble solids, and methionine. Narrow sense heritability values between and within progenies are higher for manganese content, glycine, proline and tryptophan. Regardless of the inbreeding line S5 used, heterosis gains are obtained for insertion of spike height, number of grain rows per spike, stem diameter, and zinc content, total carotenoids, soluble solids and pH. Specific heterosis’s evidenced for grain yield, glycine, serine, threonine, and phenylalanine. The multivariate approach used defines eight-character profiles regarding their genetic trends and indicates narrow sense heritability of the progeny mean as the major cause for this distinction.

Indução de mutação e mensuração da variabilidade genética em genótipos de cana-de-açúcar

The widespread usage of commercial varieties of sugar that are adapted to the agricultural system and come from parents with a small genetic distance can lead to a narrowing of the genetic basis of sugarcane. This study aimed to induce mutations and evaluate the genetic distance among the sugarcane mutants produced by different multivariate techniques. Mutations were induced and then the genetic distance among these sugarcane mutants was evaluated with the use of multivariate techniques. The study was conducted in the experimental area of the UFSM, Frederico Westphalen, RS. The genotype used for mutation induction was IAC 873396. The induction process proceeded with the placement of buds in a solution of the mutagenic agent MMS (Methyl Methane Sulfonate). A total of 22 mutations and six commercial checks were evaluated for 12 traits of agronomic interest. The analyses were: the evaluation of individual averages, Tocher’s grouping, average Euclidean distance, an analysis of principal components, and the relative contribution of characteristics. The mutation induction process generated significant patterns of genetic variability among sugarcane mutants verified by three multivariate analyses. The UPGMA clustering methods, Tocher and principal component analysis revealed similar results related to the dissimilarity of sugarcane genotypes. Genotypes 20, 24, and 10 were greater than the general average of genotypes and have a high genetic dissimilarity for traits. The yield of stems, bagasse mass, and the yield sugarcane broth are sufficient to characterize a set of sugarcane genotypes.

Adaptability, Stability and Multivariate Selection by Mixed Models

The aim of this work was to estimate the adaptability and stability of grain yield per hectare and percentage of crude protein of maize grains combined in an index, and to establish a multicharacter selection through mixed models based on an objective character and 15 auxiliary traits. The trials were conducted in the 2013/2014 agricultural year in four growing environments of the Rio Grande do Sul, BR state. The experimental design was randomized blocks arranged in a factorial scheme, being four growing sites × 15 single cross maize hybrids, arranged in three repetitions. The genotypic index, composed by the grain yield and the crude protein percentage in the grains, is the best selection strategy to achieve maize superior genotypes. The multivariate genotypes selection, considering grain yield and crude protein, is efficient. The genotypes FORMULA TL®, AS1656PRO®, P30F53Hx®, LG6304YG® and 30F53 are more adapted and stable for grain yield and percentage of crude protein, in the conditions of this study. The mixed models were efficient to employ the multicharacter selection and to contribute for maize genetic breeding.

Efeitos na produção e constituição bromatológica de silagem de híbridos de milho em diferentes ambientes

The aim of this study was to assess silage corn hybrids morphological, productive and bromatological parameters in irrigated and non-irrigated environmental conditions. The research was held in the 2010/2011 season, Campos Borges – RS. The experimental design was randomized blocks in factorial design, with two environments x eight corn hybrids, arranged in three replications. Analysis of variance showed environment x corn hybrids interaction significance for plant height, fresh and dry matter per hectare, dry matter percentage, mineral matter, crude protein, neutral detergent fiber, lignin, total and non-fibrous carbohydrates. In the irrigated environment, hybrids showed higher plant height, chlorophyll content, leaf area, fresh and dry matter per hectare, silage dry matter percentage, pH, mineral material, neutral detergent fiber, cellulose and lignin. Non-fibrous and total carbohydrate levels were higher for the non-irrigated environment. Crude protein content was higher in the non-irrigated environment. In the irrigated environment HS1356 hybrid showed higher plant height, fresh and dry matter per hectare, mineral material and neutral detergent fiber. HT4 hybrid led to higher silage crude protein content in the irrigated environment.

Efeitos de enxofre e nitrogênio na qualidade industrial e no rendimento de grãos de trigo

The consumer market’s demand and requirement for wheat grains which present a satisfactory industrial quality have driven the demand for enhanced cropping systems, especially related to nutritional aspects. In this context, the purpose of this research was to evaluate how the sulfur supplementation and the usage of nitrogen (N) affect the baking quality and the yield of the wheat grain cultivar TBIO Itaipu®. A randomized block experimental design in factorial arrangement, with two sulfur managements (with and without) and four split nitrogen managements (I: 100% of N in the double ring; II: 30% of N in the tillering period + 40% of N in the double ring + 30% of N in the ear development; III: 50% of N in the tillering period + 50% of N in the double ring; IV: 50% of N in the double ring + 50% of N in the ear development period), arranged in four repetitions. Our results showed that the sulfur supplementation increased the gluten content, which has been positively correlated with the strength and extensibility of the bread dough. This had a positive influence on the technological parameters of the flour used for baking. The splitnitrogen fertilizer application (in double ring, tillering, and ear development) increased the wheat grain yield due to the greater number of tillers per plant and also of the wheat ears per square meter.