The objective of this work was to evaluate the chemical composition of the macronutrients: nitrogen (N), phosphorus (P), potassium (K), calcium (Ca), magnesium (Mg) and sulfur (S), and micronutrients: boron (Cu), iron (Fe), manganese (Mn), molybdenum (Mo) and zinc (Zn), and the elements aluminum (Al) and sodium (Na) measured in soybean seeds from different producing regions of Brazil. This work was carried out by sampling 2543 lots of soybean seeds produced in the 2009, 2010, 2011 and 2012 growing seasons. There is high variability of macro and micronutrients concentration in soybean seeds produced in several regions of Brazil. The nitrogen, potassium, phosphorus, and calcium are the most pronounced macronutrients in soybean seeds. Among the micronutrients, iron, manganese and zinc are those with more evidence. Understanding macro and micronutrients variability is critical for improving management and fertility treats in soybean seed production fields.

The objective of this work was to evaluate the adaptability and multi-trait stability of wheat (Triticum aestivum) genotypes according to the phenotypic index of seed vigor (PIV). Thirty wheat genotypes were grown in seven environments in the state of Rio Grande do Sul, Brazil, during one crop season. In each environment, a randomized complete block design with three replicates was used. The PIV was elaborated from the following traits: first germination count, germination percentage, accelerated aging, and electrical conductivity. The evaluated phenotypic index makes it possible to define macroenvironments for the production of wheat seeds with high physiological potential and to understand the implications of the genotype x environment interaction. The phenotypic index of seed vigor is effective to rank genotypes considering multi-trait selection related to the vigor of wheat seeds produced in Southern Brazil.

The objective of this work was to evaluate the agronomic performance of corn hybrids, the interrelations of the characters with the grain yield, and to genetically discriminate the corn hybrids by means of the dispersion analysis of the canonical variables. The experiment was conducted in the agricultural crop of 2013/2014, in an area belonging to the Federal University of Santa Maria, Campus of Frederico Westphalen, RS. The experimental design was a randomized block design, with four replications. The treatments were composed of seven maize hybrids with different genetic bases and maturation cycles. The LG 6304 modified simple hybrid has higher grain yield than the others. The characters plant height, spike insertion height and number of grains per row of spike have positive interrelations with grain yield of corn hybrids. Hybrids are not grouped according to the genetic basis and maturation cycle. The canonical variables explain 94.62% of the existing genetic variation, and allows the formation of five groups of maize hybrids.

The aimed to correlate the micronutrients content in soybean seeds with their physiological potential. The work was developed in the Federal University of Pelotas, in the facilities of the Seed Science and Technology Graduate Program. The experimental design was randomized blocks in arranged in four replicates. The micronutrients measured were: B, Cu, Fe, Mn, Mo, Zn, Al and Na. The magnitudes of micronutrients are dependent on the genetic constitutions of soybean cultivars. Higher variations are expressed for boron, copper, manganese, zinc, molybdenum, sodium and aluminum content, while iron is the most stable micronutrient in soybean seeds. Molybdenum and copper are characterized as determining micronutrients for physiological quality of soybean seeds.

A espécie Solanum americanum (maria-pretinha) é considerada planta daninha; por possuir elevada habilidade competitiva e agressividade, ela reduz a produtividade dos cultivos. O trabalho foi conduzido em casa de vegetação e objetivou analisar o crescimento e a partição de assimilados em plantas de maria-pretinha submetidas a três níveis de sombreamento. As plantas foram coletadas em intervalos regulares de sete dias após o transplante até o final do ciclo, sendo determinada a massa seca e a área foliar. A partir dos dados primários, foi aplicada a análise de crescimento, sendo calculados a massa seca total (Wt), as taxas de produção de matéria seca (Ct), crescimento relativo (Rw) e assimilatória líquída (Ea), o índice de área foliar (L), as razões de área foliar (Fa) e massa foliar (Fw), a área foliar específica (Sa), a partição de matéria seca entre órgãos e o número de frutos. Plantas de maria-pretinha cresceram e se desenvolveram melhor sob condição intermediária de luz (65%), em que atingiram maior Wt, Ct, L, Fa, matéria seca de caule, matéria seca de fruto e maior número de frutos, enquanto a luz plena e a redução da luminosidade em nível acentuado, de maneira mais marcante, afetaram negativamente o crescimento e o desenvolvimento, o que possivelmente pode influenciar a habilidade competitiva da maria-pretinha.