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This study aimed to evaluate the proximate composition of quinoa grown in the central plateau of the Brazilian Cerrado during the summer and winter periods. Grains of the Kancolla, BRS Piabiru, and BRS Syetetuba varieties were evaluated for parameters such as moisture, dry matter, ash, protein, lipids, carbohydrates, crude fiber, calcium, magnesium, phosphorus, sulfur, and potassium. It was observed that the proximate composition of quinoa grains varies depending on the cultivation period, with higher averages in the summer. However, in both periods, the Brazilian averages were higher than those reported in the worldwide literature for quinoa grains. Regarding the mineral components, grains grown in the summer period had higher levels than in the winter, when compared to the worldwide standards for quinoa. The BRS Syetetuba variety showed superiority in the levels of the evaluated parameters compared to the other varieties.

The centesimal analysis of grains is performed with the crushed sample as a way to minimize time and reduce costs with reagents. However, milling is an expensive task when there are a large number of samples. Thus, this work evaluated the need for grinding quinoa grains for the determination of protein and lipids by the semi-micro Kjeldahl method, using concentrated sulfuric acid and a temperature of 450 °C, and by the methodology using petroleum ether in an automatic extractor (lipids ). There was no statistically significant difference between whole and ground grain samples. Thus, it is recommended that, for protein and lipid analysis with these methodologies, it is not necessary to grind the grains.

The variations in seed quality and scarcity vigor studies have been limiting factors in crop establishment at different regions of its Andes origin. The present study aimed to evaluate the physiological quality of quinoa seeds, from cultivars of Brazil, Colombia and Ecuador. The research was conducted in the Seeds Technology Laboratory of the University of Brasilia, Brazil, through the tests of germination, hypocotyl and radicle length and accelerated aging test. Eighteen genotypes selected from different cultivars were evaluated using the F Test and Scott-Knotts. In addition, hierarchical cluster analysis was performed using the Ward method and Cluster analysis by k-means. The germination average was 80.81%; the hypocotyl and radicle length characteristics showed an average of 9.11 and 11.27 mm, respectively. The average germination after the accelerated aging test was 75.52%, with better results for the genotypes Piartal and Aurora. Quinoa genotypes showed variability in seed vigor, allowing determining differences in germination potential at high stress conditions. The application of methods developed for the analysis of quinoa seeds at 25°C and 4 days has been effective in screening for quality. Seed quality assessments in quinoa allow defining limits of tolerance to adverse conditions, facilitating selection in breeding programs. Key words: Accelerated aging test, Chenopodium quinoa, germination, selection, vigor.

The success of barley (Hordeum vulgare L.) cultivation and its adaptation to cropping systems relies on the knowledge and utilization of existing variability in germplasm banks. The objective of this work was to analyse diversity among pre-selected barley accessions to organize a working collection and to identify genotypes for a breeding program for irrigated barley in the Brazilian Savannah. The field experiment was conducted under irrigation in Planaltina, DF, Brazil. The plant population consisted of 433 accessions plus BRS 180 and BRS 195 as checks. The accessions were evaluated using fifteen morpho agronomic descriptors, in which 11 quantitative and four discrete. The interpolated control design was used for the statistical analysis. A genetic distance matrix was calculated using Gower’s coefficient. From the matrix, a grouping analysis was conducted, using the optimizing Tocher method and the graphic dispersion distance. The genetic distances varied between 0.025 and 0.572, with a mean of 0.256. The accessions were distributed in 18 groups by the Tocher method, which was directly related to the graphic dispersion. The existing genetic divergence in the collection under study helped the definition of accessions in crossing blocks from breeding programs directed to the savannah environment.

This work aimed at evaluating and comparing agronomic characteristics of 15 quinoa (Chenopodium quinoa Willd) genotypes cultivated in two altitudes and sowing densities. The experiment initiated by individual plant selection in Brasília, DF, followed by progeny evaluation in Colombia, at 1,100 m and 1,850 m altitude and population densities of 30 and 12 plants m-1, with row spacing of 0,50 m. Eleven progenies and four commercial cultivars were tested. The progenies were obtained by selecting individuals in BRS Syetetuba based on plant height, grain and dry matter yield, harvest index and 1,000 grain weight. The genotypes with the highest grain yield were BRQ 8 (2,283 kg ha-1), Aurora (2,121 kg ha-1) and BRQ 4 (2,043 kg ha-1). In general, the genotypes had early plant cycle, from emergence to physiological maturity of 100-110 days at high plant density for the two altitudes. It is concluded that exploring variability in progenies originated from natural crosses is effective in the adaptation of quinoa to tropical environments. Moreover, genotypes tested in the Cerrado (Brazilian Savannah) maintain the same response relation when evaluated in Colombia.

The objective of this paper was to evaluate the genetic and agronomic parameters of soybean F2 progenies in the Federal District, Brazil, from twenty biparental crosses, between parents with absence of lipoxygenases and parents with long juveniles. The experiment was conducted in the Federal District, crop 2013/14. The experimental design was randomized blocks with four replicates. The following were evaluated: agronomic characteristics, estimated heritability, relationship between the genetic and environmental variation coefficient and phenotypic correlations between the characters. Hybridizations between cultivars, with a long juvenile period and cultivars intended for human consumption, caused a great variation in the maturation cycle. The Amaralina x UFVTN105 cross was more likely to be selected for plant height, while the UFVTN105 x M8867 cross showed a higher frequency of recombinants for grain production. Based on heritability and the CVg/CVe quotient, the selection by number of days for maturation (NDM) and plant height at maturity (PHM) is effective in the F2 segregating population. Positive and significant correlations of strong magnitude between the variables NDM x PHM and NPP (number of pods per plant) x GY (Grain yield) and of medium magnitude between PHM x HPI (height first pod insulation), allow indirect selection in obtaining soybean genotypes with high grain yield per plant and with better flavor in early generations.

Objetivou-se com este trabalho estimar parâmetros geneticos (herdabilidade, coeficiente de variacao genetica e razao da variacao genetica e ambiental CVg/CVe), calcular as correlacoes fenotipicas e dispersao grafica entre caracteres agronomicos em populacoes de soja formadas por cruzamento biparentais e seus genitores. A selecao foi concentrada em altura de plantas (AP) e de insercao de vagem (AIV), numero de dias para maturacao (NDM), numero de vagens por planta (NVP) e rendimento de graos (RG). O experimento foi conduzido no Distrito Federal, latitude 15°56’S, longitude 47°56’W e altitude de 1.080 m, em latossolo vermelho amarelo. A semeadura foi realizada em dezembro de 2013. O delineamento experimental foi o de blocos casualizados com quatro repeticoes. Os tratamentos foram constituidos por 22 genotipos (10 genitores e 12 cruzamentos). A parcela experimental foi constituida por uma linha com 2,5 m de comprimento, espacada por 100 cm. A analise mostrou ganhos para os caracteres estudados, medidos pela herdabilidade (ha2). A razao CVg/CVe mostrou selecao favoravel para NDM, AP, NVP e RG. A maior variabilidade genetica (CVg) encontrada foi para NVP e RG. As correlacoes apresentaram magnitude media entre os caracteres NDM e AP, NDM e AIV, AP e AIV, AP e NVP, e NVP e RG. A selecao por NVP resulta em maior rendimento por planta. A dispersao grafica permitiu observar os genotipos de forma isolada, indicando os cruzamentos mais promissores para serem avancados no procedimento de selecao.

This study aimed at evaluating physiological and agronomic components of food type soybean introduced in the State of Tocantins, as compared to common type locally adapted cultivars. The experiment was conducted at the Federal University of Tocantins, located at 11° 43' S and 49° 04' W. The experimental design was randomized complete block with four cultivars and four repetitions of food type BRSMG790A and BRS 257, and common type A7002 and M 8585. Evaluations were made on plant height (PH), number of days to flowering (NDF), number of days to maturity (NDM), number of days of the reproductive period (NDPR), number of pods per plant (NPP), dry matter yield (DMY), grain yield (GY), leaf area (LA) and growth rates: leaf area index (LAI), leaf area ratio (LAR), net assimilation rate (NAR), absolute growth rate (AGR) and relative growth rate (RGR). The BRSMG 790A and BRS 257 had lower PH, LA, LAI, LAR, NAR, AGR and RGR, reflected by NDF and maturity, reducing NPP, DMY and GY. These lypoxigenase free cultivars are not adapted to soybean commercial production at low the latitudes of Tocantins but can be employed in hybridization with long-juvenile, locally adapted cultivars, being a source of genetic diversity in breeding programs.

The objective of this work was to evaluate the solubility of the micronutrients copper, nickel, and zinc, chemically extracted from silicate agrominerals, as alternative sources of potassium for lettuce (Lactuca sativa) and rice (Oryza sativa) cultures, as well as their availability to the plants. The micronutrient contents of five agrominerals (alkaline ultramafic, biotite schist, volcanic breccia, phlogopite schist, and mining by-product from Chapada) were evaluated, after being extracted by the citric acid, hydrochloric acid, diethylenetriaminepentaacetic acid, 3051A, neutral ammonium citrate, and Mehlich-3 methods. The agrominerals, at the doses of 0 (control), 200, 400, and 600 kg ha-1 K, were mixed to soil where lettuce and rice were cultivated. The agrominerals presented a low solubility of Ni, Cu, and Zn, with lower contents in lettuce shoots and rice grains than the corresponding soluble standards in sulfate form. The availability of micronutrients to the plants increased with the use of agrominerals, in comparison with the control. Similarities were observed in micronutrient solubility and availability between the different groups of agrominerals. The solubility and availability of Cu, Ni, and Zn depend on the solubility of the minerals that compose the agrominerals. Resumo: O objetivo deste trabalho foi avaliar a solubilidade dos micronutrientes cobre, níquel e zinco, extraídos quimicamente de agrominerais silicáticos, como fonte alternativa de potássio para as culturas de alface (Lactuca sativa) e arroz (Oryza sativa), bem como sua disponibilidade para as plantas. Avaliaram-se os teores de micronutrientes de cinco agrominerais (ultramáfica alcalina, biotita xisto, brecha vulcânica, flogopita xisto e subproduto de mineração de Chapada), após extração pelos métodos ácido cítrico, ácido clorídrico, ácido dietilenotriamino penta-acético, 3051A, citrato neutro de amônio e Mehlich 3. Os agrominerais, nas doses de 0 (controle), 200, 400 e 600 kg ha-1 de K, foram misturados em solo com cultivo de alface e arroz. Os agrominerais apresentaram baixa solubilidade de Ni, Cu e Zn, com menores teores em folhas de alface e grãos de arroz que o padrão solúvel correspondente na forma de sulfato. A disponibilidade de micronutrientes para as plantas aumentou com uso dos agrominerais, em comparação ao controle. Foram observadas similaridades na solubilidade e na disponibilidade de micronutrientes entre os diferentes grupos de agrominerais. A solubilidade e a disponibilidade de Cu, Ni e Zn dependem da solubilidade dos minerais que compõem os agrominerais.

The standard germination tests have been commonly used on commercial grain crops, such as soybean, field beans, rice and maize. However, there are no standard tests for potential new crops; quinoa being one of them. This work is aimed at evaluating the effect of substrate, temperature and counting time in seed germination of quinoa. The following treatments were used in tests with seeds: on blotter paper, between blotter paper, on sand and within sand, all previously soaked with distilled water. These substrates were combined to the temperatures of 15, 20, 25, 30°C, and alternated between 20 to 30°C. The experiment was conducted on an entirely randomized factorial design 5 × 4 (temperature × substrate) with 4 repetitions. Normal seedlings, abnormal seedlings and dead seeds were counted until stabilized. The germination velocity index and mean time for germination were calculated. From the results, it was concluded that germination test of quinoa seeds should be conducted at 20 to 30°C alternate temperatures, on or between blotter paper, with initial count at 2 days and final count at 4 days. Key words: Chenopodium quinoa willd., substrate temperature, counting time, seed viability.

Quinoa has grown importance in the world due to the nutritional quality of its grains and crop adaptability to diverse climatic conditions. One problem that limits its cultivation is the reduced viability of seeds during storage and the information is rather scarce. This work aimed at evaluating the physiological quality of quinoa seeds along time when submitted at storage conditions and packaging. An entirely randomized experiment was conducted on factorial scheme 2 x 3 x 6 with four repetitions. The treatments consisted of 2 storage conditions: lab environment and Biochemical Oxygen Demand (B.O.D.) chamber set at 4±2°C and 90% relative humidity (RH); 3 package types: permeable, semi-permeable and impermeable; and 6 evaluations: before storage (0), 60, 120, 180, 240 and 300 days after storage. Seed viability was determined by the standard germination test while vigor by accelerated aging test, emergence in sand and emergence speed index. The use of impermeable packaging kept at low temperature maintained the physiological quality of seeds during 300 days of storage. The seeds kept in permeable or semi-permeable packaging under uncontrolled temperature and humidity conditions were viable only for 180 days. The permeable package using kraft paper was the least efficient to conserve physiological quality of quinoa seeds. It was demonstrated that quinoa seeds are rather sensitive to high temperature, loosing viability in short time. Key words: Chenopodium quinoa, seed vigor, seed viability, seed conservation, packaging.

Ammonia volatilization (N-NH3) is one of the main pathways of Nitrogen loss reducing nitrogen use efficiency in coffee orchard. This work aimed at quantifying ammonia volatilization (N-NH3) losses from N-sources to be used in coffee plantations fertilization in Brazil. The experiment was conducted in the field on a dystrophic red latosol (Ferralsol in FAO's classification) at the Coffee Research Sector, University of Lavras, MG, Brazil. The experimental design was of complete randomized blocks with three repetitions of the following treatments: conventional urea, ammonium nitrate and urea + 0.15% Cu and 0.4% B, urea + anionic polymers, urea + elementary sulfur (S0) + polymers, and urea + plastic resin. These N sources were split into three doses of 150 kg ha-1 and band applied. The N-NH3 losses by volatilization and variations of pH (H2O) were measured, before and after N application. The N-sources contributed to reduce the soil pH, measured after the third nitrogen fertilization. The N-NH3 losses by volatilization (average from three applications) was as follows: urea + anionic polymers (35.8%) > conventional urea (31.2%) = urea + S0 + polymers (31.0%) > urea + 0.15% Cu + 0.4 % B (25.6%) > urea + plastic resin (8.6%) = ammonium nitrate (1.0%).

This study aimed to estimate the potential of chickpea cultivation when subjected to low soil moisture conditions and to identify genotypes with better agro...

Chenopodium quinoa seeds have high protein content. The nutritional value of quinoa is superior compared with traditional cereals. Its essential amino acid composition is considered next to the ideal, and its quality matches that of milk proteins. In this study, the seed storage proteins from Chenopodium quinoa were extracted, fractionated, partially purified, and characterized. The structural characterization was performed by Tricine-SDS-PAGE and two-dimensional electrophoresis, and it confirmed the presence of proteins of molecular weight of 30 and 7kDa, probably corresponding to lectins and trypsin inhibitors, respectively. The functional characterization of these proteins evidenced their activity as antinutritional factors due to their in vitro digestibility. Quinoa proteins have an excellent amino acid composition with many essential amino acids. In vitro digestibility evaluation indicated that heat-treated samples showed a more complete digestion than the native state samples. Quinoa seeds can be an important cereal in human diet after adequate heat treatment.

The increasing world population has led into big food and raw material demand, with high pressure on agriculture. In Brazil, potassium fertilizers are mostly imported rising interest on rocks and mining rejects as alternative sources. The objective of this work was to evaluate the effect of crushed rocks over mineral nutrition, yield and efficiency of potash fertilization in rice. The experiment was carried out under greenhouse conditions in pots with 3.7 kg of Oxisol soil samples. The experimental design was completely randomized, in a factorial layout 4 × 6, comprising six crushed rocks used as alternative multinutrient fertilizer (breccia, biotite schist, ultramafic, Chapada byproduct, mining byproduct and phlogopite), and four doses based on potassium (0, 200, 400, 600 kg K2O ha-1), with four replications. The concentration and accumulation of potassium, copper, zinc and nickel in rice shoot dry mass were determined. These data were used to evaluate the efficiency index of K-source rocks on fertilization. It was shown that crushed rocks promote alterations in mineral nutrition, grain yield and potassium use efficiency, remarking their potential to be used as alternative fertilizer in rice cropping systems. Key words: Alternative nutrient source, micronutrient, fertilization efficiency, plant nutrition, soil conditioner.

RESUMO Objetivou-se com este trabalho comparar o valor forrageiro do milheto e trigo-mourisco, sob irrigação, em diferentes idades de corte. Utilizou-se delineamento experimental em blocos ao acaso, com os tratamentos arranjados em modelo de parcelas subdivididas. As plantas foram cultivadas durante a estação seca, sob irrigação e colhidas em três idades de corte, 47, 57 e 67 dias (tratamentos). Foram determinados os teores de matéria seca (MS), proteína bruta (PB), fibra em detergente neutro (FDN), fibra em detergente ácido (FDA), matéria mineral e produção de gases in vitro e a produção de matéria seca. A produção do trigo-mourisco (2301, 3144 e 4471 kg MS/ha) foi superior à do milheto (437, 592 e 2224 kg MS/ha) nas três idades de corte. Os teores de PB do milheto foram, em média, 22,3% nas três idades de corte, mas no trigo-mourisco reduziu de 23,8% no primeiro corte, para 14% nos demais cortes. O trigo mourisco apresentou maior teor de FDN no primeiro corte 57,6% contra 52,1% do milheto, entretanto diminuiu no segundo e terceiro cortes, 46,8% e 41,2%, respectivamente, enquanto que no milheto mantiveram-se em 55,1% e 52,7% no segundo e terceiro corte. Os teores de FDA forma mais elevados para o trigo mourisco em comparação com o milheto nas três idades de corte estudadas. A produção de gases foi maior para o trigo mourisco em comparação ao milheto, com exceção do primeiro corte, quando o trigo apresentou maiores taxas de fermentação. O trigo mourisco apresentou qualidade como forrageira, sendo mais produtivo e nutritivo do que o milheto durante o período seco, sob irrigação. SUMMARY This trial compared forage production and quality of Pearl Millet and Buckwheat in three cutting age on irrigation conditions during dry season, evaluated in a randomized block split plot design with tree replications. Was determined content of Dry Matter (DM), Crude Protein (CP), Neutral Detergent Fiber (NDF), Acid Detergent Fiber (ADF), Mineral Matter (MM) and in vitro gas production. Forage production of Buckwheat was higher than Pearl Millet in all the cutting ages. Pearl Millet CP content was similar to all three cuts but Buckwheat CP content was higher in the first cut and reduced in the others. The NDF content of Buckwheat was higher in the first cut and reduced in the others, meanwhile Pearl Millet presented low NDF value in the first cut but increased in the second and third cut. The Buckwheat presented high ADF content than Pearl Millet in all the cuts. In vitro gas production from Pearl Millet was higher in the first cut but more high for Buckwheat in the second and third cuts. Buckwheat produced more forage with high quality than Pearl Millet during dry season.

Saponin-free quinoa genotypes were evaluated in summer and autumn–winter sowings, for phenotypic traits and yield stability. They were obtained by single plant-progeny selection from hybrids, as part of the breeding efforts in adapting the crop to the Brazilian Savannah environments. The soils (Ferralsols) were limed and fertilized prior to cultivation. The experiment was sown in two dates: 20th December 2006 (summer), and 30th April 2007 (autumn–winter), at 15°39′ and 16°14′ S latitude, 47°27′ and 47°44′ W longitude, with altitudes of 976 and 1,110 m, respectively. The mean temperature and rainfall for the summer sowing were 23.0°C and 723 mm. In autumn–winter, under controlled irrigation, the mean temperature was 2.9°C lower than in summer, when plants were exposed to water logging spells. The treatments consisted of fourteen selected genotypes and the varieties Kancolla, BRS Piabiru and Q4.5, used as controls. Comparisons were based on plant height, biomass and grain yield, harvest index (HI) and 1,000 seed weight. The experimental design was a complete randomized bloc, with three replications. Analysis of variance was performed for each sowing and jointly. Statistical differences for the environments were evident only for grain size and plant height. The performance of selected genotypes in each sowing date and in the joint analysis, allows saying that populations Q0779, Q0780 and Q0782 are potentially useful in the acquisition of stable genotypes for the Brazilian Savannahs.

A acidez do solo é fator limitante para a maioria das plantas cultivadas no Cerrado Brasileiro. A toxidez causada por alumínio (Al) é especialmente séria na subsuperfície, que permanece ácida após o uso de corretivos, por impedir o crescimento radicular e causar suscetibilidade à seca e desbalanceamento nutricional. Aqui objetivou-se a seleção de genótipos de soja com maior tolerância ao Al, pela associação de experimentos em hidroponia e no campo. Cruzamentos incluindo genótipos selecionados no Cerrado foram realizados. Sementes de indivíduos contrastantes, selecionados em hidroponia na geração F2 pelo crescimento radicular, foram obtidas para avaliação de progênies em F3, no campo, e em F4, novamente em hidroponia. Rendimento de grãos e de biomassa das progênies selecionadas foram superiores aos genitores, no experimento em solo ácido. Esses resultados foram confirmados pelo desempenho em hidroponia, indicando que o método de seleção pode ser empregado com êxito em programas de melhoramento para adaptação de cultivos a condições de acidez subsuperficial do solo. PALAVRAS-CHAVE: Acidez sub-superficial; Glycine max; estresse; genótipo; melhoramento de plantas. Soil acidity is a limiting factor for most of the cultivated plants in the Brazilian Savannah. Toxicity caused by aluminum (Al) is especially serious in the acid subsurface, which remains acidic after soil has been amended, by hindering root growth and causing drought susceptibility and nutritional unbalance. This research aimed at selecting soybean with increased tolerance to Al through association of hydroponics and field experiments. Crosses including savannah adapted genotypes were obtained. Seeds of contrasting individuals, selected in hydroponics at F2 generation for root growth, were obtained for progeny evaluation at F3, in the field, and at F4 in hydroponics. Grain production and total dry matter of selected progenies were superior to the parentals, in the acid soil experiment. These results were confirmed by performance in hydroponics, indicating the method may be successfully employed in breeding programs for crop adaptation to subsurface acid soil conditions. KEY-WORDS: Subsurface acidity; Glycine max; Al stress; plant breeding.

Soil acidity is a limiting factor for most of the cultivated plants in the Brazilian Savannah. Toxicity caused by aluminum (Al) is especially serious in the acid subsurface, which remains acidic after soil has been amended, by hindering root growth and causing drought susceptibility and nutritional unbalance. This research aimed at selecting soybean with increased tolerance to Al through association of hydroponics and field experiments. Crosses including savannah adapted genotypes were obtained. Seeds of contrasting individuals, selected in hydroponics at F2 generation for root growth, were obtained for progeny evaluation at F3, in the field, and at F4 in hydroponics. Grain production and total dry matter of selected progenies were superior to the parentals, in the acid soil experiment. These results were confirmed by performance in hydroponics, indicating the method may be successfully employed in breeding programs for crop adaptation to subsurface acid soil conditions. KEY-WORDS: Subsurface acidity; Glycine max; Al stress; plant breeding. A acidez do solo é fator limitante para a maioria das plantas cultivadas no Cerrado Brasileiro. A toxidez causada por alumínio (Al) é especialmente séria na subsuperfície, que permanece ácida após o uso de corretivos, por impedir o crescimento radicular e causar suscetibilidade à seca e desbalanceamento nutricional. Aqui objetivou-se a seleção de genótipos de soja com maior tolerância ao Al, pela associação de experimentos em hidroponia e no campo. Cruzamentos incluindo genótipos selecionados no Cerrado foram realizados. Sementes de indivíduos contrastantes, selecionados em hidroponia na geração F2 pelo crescimento radicular, foram obtidas para avaliação de progênies em F3, no campo, e em F4, novamente em hidroponia. Rendimento de grãos e de biomassa das progênies selecionadas foram superiores aos genitores, no experimento em solo ácido. Esses resultados foram confirmados pelo desempenho em hidroponia, indicando que o método de seleção pode ser empregado com êxito em programas de melhoramento para adaptação de cultivos a condições de acidez subsuperficial do solo. PALAVRAS-CHAVE: Acidez sub-superficial; Glycine max; estresse; genótipo; melhoramento de plantas.

O gênero Amaranthus compreende várias espécies de plantas dicotiledôneas cujas folhas e sementes são regularmente consumidas como alimento em diversos países, entre os quais não se inclui o Brasil. As espécies graníferas se destacam pela vantagem da rapidez de crescimento e produção, possibilitando o cultivo em condições de escassez de umidade na fase reprodutiva. Dadas suas nobres características nutricionais, este grão se apresenta como um alimento naturalmente balanceado, com propriedades de alimento funcional. O alto valor nutritivo e as características físico-químicas da proteína fazem com que a farinha possa ser utilizada na fortificação de cardápios consumidos pelas populações de baixa e alta renda, sem distinção. As proteínas do grão de amaranto têm ainda alto potencial na elaboração de produtos farináceos isentos de glúten, o que torna este produto de grande importância na ampliação da oferta de alimentos nutritivos para portadores da doença celíaca. Considerando o conjunto de suas propriedades, muito atraentes para a agricultura familiar ou o agronegócio, além do fato da Embrapa ter adaptado cultivares ao cultivo no Cerrado, é difícil entender como o país não aderiu ainda à produção e ao consumo deste produto.

Asian soybean rust caused by Phakopsora pachyrhizi, occurs in all soybean production regions of the world. Rust is the most destructive foliar disease of soybean and can cause yield losses of over 80%. To date, six race-specific resistance genes have been identified in plant introductions. However, races of P. pachyrhizi able to overcome the resistance conferred by these genes have evolved. Due to the limited availability of resistant varieties, fungicide application is the only management tool available for farmers, which significantly raises the production cost and the risk of environmental and human contamination. Thus, the transfer of resistance genes through classical breeding followed by marker-assisted selection allows the development of resistant varieties and their use as an efficient and cost-effective method for controlling soybean rust. The objective of this review is to provide a broad overview of the Asian soybean rust resistance, and a useful tool to guide future researches as well.

A produtividade da soja no Cerrado torna a região competitiva nacional e internacionalmente. Entretanto, para atingir estabilidade produtiva e aprimorar o sistema de produção de grãos, torna-se necessária a obtenção de cultivares com resistência a doenças, como o cancro-da-haste, e com ciclo menor. Como resultado dos esforços da pesquisa, selecionou-se a cultivar BRS Milena. Os resultados, em todos os testes, mostram uma elevada produtividade e estabilidade em relação às cultivares usadas como testemunhas. O número de dias para maturação a classifica como uma cultivar de ciclo médio. Apresenta altura de plantas adequada à mecanização, e à ausência de acamamento nas condições em que tem sido testada. A 'BRS Milena' apresenta resistência às principais doenças da soja, tais como o cancro-da-haste, a mancha-olho-de-rã, o oídio e a pústula bacteriana. _________________________________________________________________________________ ABSTRACT The high productivity of soybeans in the Brazilian Savannah (Cerrado) has turned the region into a major grain producer, at local and international competitive levels. To achieve yield stability and improve the production systems, however, the acquisition of disease-resistant and early maturity cultivars is necessary. 'BRS Milena' was selected as a result of research efforts. Results over the tests have shown it is highly productive and stable, in relation to cultivars commonly grown in the region (controls). Number of days to maturity defines it as a mid-cycle cultivar, with suitable plant height for mechanical harvest and nonlodging under the environments of testing. In addition, 'BRS Milena' is resistant to the main soybean diseases, like stem cancker, frogeye leaf spot, powdery mildew and bacterial pustule.

O objetivo desse estudo foi avaliar o efeito da aplicação de fontes alternativas de nutrientes na nutrição, produção e eficiência da adubação potássica na alface. O experimento foi conduzido em casa de vegetação, em vasos com 3,7 kg preenchidos com um Latossolo Vermelho Amarelo distrófico de textura média. O delineamento experimental foi inteiramente casualizado e os tratamentos foram distribuídos em arranjo fatorial 4 x 6, sendo quatro doses de potássio (0; 200; 400; 600 kg ha-1 de K2O) e seis fontes alternativas de nutrientes (brecha, ultramáfica, biotita xisto, flogopitito, subproduto de mineração e subproduto de chapada), com quatro repetições. Foram determinados o teor e o acúmulo de potássio (K), cobre (Cu), zinco (Zn) e níquel (Ni) na parte aérea da alface e com esses dados foram calculados dois índices de eficiência da adubação potássica. As aplicações de doses crescentes das fontes alternativas de nutrientes promoveram melhorias na nutrição e aumentos na produção da alface. A eficiência da adubação potássica diminuiu com o aumento nas doses de potássio aplicadas pelas fontes alternativas de nutrientes, sendo que o subproduto de mineração e a ultramáfica foram superiores às demais fontes. Diante disso, pode-se afirmar que as rochas silicáticas moídas e os subprodutos de mineração constituem uma opção para adubação em sistemas de produção orgânica e convencional. The aim of this study was to evaluate the effect of alternative sources of nutrients on the nutrition, yield and efficiency of potassium fertilization in lettuce. The experiment was carried out in a greenhouse, using 3.7 kg pots filled with a dystrophic red-yellow Latosol of medium texture. The experimental design was randomized, with treatments divided into a 4 x 6 factorial: four doses of potassium (0; 200; 400; 600 kg ha-1 K2O) and six alternative sources of nutrients (breccia, ultramafic, biotite schist, phlogopite, and mining and Chapada by-products), with four replications. Content and accumulation were determined for potassium (K), copper (Cu), zinc (Zn) and nickel (Ni) in the lettuce shoots, and from these data two indices were calculated for the efficiency of potassium as a fertilizer. The application of increasing values of alternative sources of nutrients promoted improvements in nutrition and increases in lettuce yield. The efficiency of potassium fertilization decreased with the increase in values of potassium taken from alternative nutrient sources, with the mining by-products and the ultramafic being superior to the other sources. Crushed silicate rocks and mining by-products can therefore both be used as fertilizer in organic and conventional production systems.