Production of lettuce, cucumber and sweet pepper seedlings in substrate with different combinations of sand, soil and Plantmax    .

RESUMO-Este trabalho teve como objetivo determinar a metodologia mais eficiente para superação da dormência em sementes de Myracrodruon urundeuva. As sementes foram submetidas a 16 tratamentos: testemunha-sementes intactas (T 1); escarificação mecânica com lixa d'água nº. 80 por 3, 6 e 9 min (T 2 , T 3 e T 4 , respectivamente), imersão em ácido sulfúrico por 2, 4, 6, 8, 10 e 12 min (T 5 , T 6 , T 7 , T 8 , T 9 e T 10 , respectivamente), escarificação mecânica com lixa d'água nº. 80, por 3, 6 e 9 min, seguida de embebição em água na temperatura ambiente por 24 h (T 11 , T 12 e T 13 , respectivamente) e escarificação mecânica com lixa d'água nº. 80, por 3, 6 e 9 min, seguida de embebição em solução de nitrato de potássio (KNO 3) na temperatura ambiente por 24 h (T 14 , T 15 e T 16 , respectivamente). Os efeitos foram avaliados por meio de testes de emergência e de vigor (percentual de emergência, primeira contagem e índice de velocidade de emergência, comprimento e massa seca das plântulas). O delineamento utilizado foi o inteiramente ao acaso, com quatro subamostras de 25 sementes, sendo as médias comparadas pelo teste de Scott-Knott. Os resultados dos tratamentos envolvendo a embebição em água e em KNO 3 não foram satisfatórios para superar a dormência de sementes de M. urundeuva. Constatou-se que houve diferença significativa entre os tratamentos em todas as variáveis avaliadas, e a dormência pôde ser superada eficientemente pela imersão em ácido sulfúrico por 12 min. Palavras-chave: Emergência, dormência, sementes florestais e planta medicinal. PRE-GERMINATION TREATMENTS IN Myracrodruon urundeuva FREIRE ALLEMÃO SEEDS ABSTRACT-This study was carried out aiming at determining the most efficient methodology to overcome dormancy in Myracrodruon urundeuva seeds. The 16 treatments employed were: control-intact seeds (T 1); mechanical scarification with sandpaper for 3, 6 and 9 minutes (T 2 , T 3 and T 4 , respectively), immersion in sulfuric acid pondered for 2, 4, 6, 8, 10 and 12 minutes (T 5 , T 6 , T 7 , T 8 , T 9 and T 10 , respectively), mechanical scarification with sandpaper of water number. 80, for 3, 6 and 9 minutes, followed by immersion in water at room temperature during 24 hours (T 11 , T 12 and T 13 , respectively) and mechanical scarification with sandpaper of water number. 80, for 3, 6 and 9 minutes followed by immersion in solution of potassium nitrate (KNO 3) at room temperature during 24 hours (T 14 , T 15 and T 16 , respectively). The effects were appraised through emergency and of vigor tests (percentile of emergency, first count and index of emergency speed, length and mass evaporates of the seedlings). It was used a completely randomized experimental design with four replicates of 25 seeds and the averages were compared through the Scott-Knott test. The treatments that involvd water and KNO 3 soaking were notsatisfactory to overcome the dormancy of seeds of M. urundeuva. There were significant differences among the treatments for all variables and the most efficient treatment to overcome dorma...

RESUMOA cultura do girassol (Helianthus annuus L.) pode ser conduzida em diversas épocas do ano, destacando-se desta forma, entre as culturas viáveis de serem exploradas nas savanas (lavrados) de Roraima. Entretanto, as cultivares podem apresentar diferenças de adaptação e desenvolvimento dependendo da área de cultivo. Assim, desenvolveu-se este estudo comparativo em área experimental da Embrapa Roraima em 2000, visando avaliar o desempenho de seis cultivares (Agrobel 910; Agrobel 920; Cargill 11; Embrapa 122; Morgan 742; e Rumbosol 91) semeadas em duas épocas (seca, com irrigação suplementar; e chuvosa) em Boa Vista, Roraima. Utilizaram-se parcelas subdivididas num delineamento de blocos ao acaso com quatro repetições, sendo as duas épocas de semeadura em 20 de janeiro e 19 de julho. As subparcelas constaram de quatro fileiras de 6 m, distanciadas de 0,90 m, sendo 0,30 m o espaçamento entre plantas. As cultivares Cargill 11, Rumbosol 91 e Agrobel 910 foram as mais produtivas para cultivo nas condições climáticas das savanas de Roraima, e a semeadura em janeiro é mais indicada, comparada a de julho. PALAVRAS CHAVES emergência; cultivares; Helianthus annuus Avaliation of Sunflower Cultivars in Savanna Ecosystem

-Nitrogen is the nutrient that limits most the production in the culture of sunflower (Helianthus annuus L). The nutritional requirements among cultivars of the same species is distinct, under the same conditions of culture and for the same agricultural year. With the objective of evaluating four different ways of nitrogen application in the production components of different genotypes of sunflower, an experiment was carried out in a randomized block design in a 3 x 4 factorial scheme (genotypes x ways of nitrogen applying) with four replicates . The treatments consisted on the combination of three varieties: Agrobel 960, Agrobel 962 and V -2000 and four different ways of nitrogen application: 100% at 20 days after sowing (DAS) -(0-100-0-0); 30% at sowing and 70% at 20 DAS -(30-70-0-0); 30% at sowing, 30% at 20 DAS e 40% at 40 DAS 20% at sowing, 30% at 20 DAS,. Measured variables were: height of the plant, height of the capitulum, diameter of the stem, diameter of the capitulum and achene yield. The ways of nitrogen application affected all components of yield. The N formulation (30-70-0-0) has determined the best results for the variables studied, but the form (30-30-40-0) provided results comparable to treatment (30-70-0-0); treatments where N was applied as (20-30-30-20) caused decrease in the performance of sunflower for all variables. The varietal effect was observed only for plant height and height of the capitulum. The highest yield of achene achieved was 1.639 kg ha-1, with no superiority for the hybrids Agrobel 960 and 962 in relation to the variety 122/V2000 Embrapa.

o objetivo de estudar métodos para o alívio da dormência de sementes de paricarana. O delineamento experimental foi o inteiramente ao acaso com 4 repetições de 50 sementes. Os tratamentos foram: escarificação mecânica com lixa d'água; imersão em ácido sulfúrico (pa) por 5 e 10 minutos; imersão em álcool etílico por 5 e 10 minutos e testemunha, sem tratamento prévio das sementes. As sementes foram incubadas a 25 o C no interior de placas plásticas 'gerbox', com papel "germitest" umedecido. Através de avaliações regulares, verificou-se os parâmetros porcentagem de germinação, porcentagem de sementes duras, índice de velocidade de germinação e porcentagem de plântulas normais ao final de 30 dias. A contagem diária das sementes germinadas foi feita durante 30 dias. Os resultados demonstraram que os tratamentos pré-germinativos promoveram a germinação de paricarana, sendo que a escarificação com ácido sulfúrico (5 minutos), revelou ser o método mais efetivo para o alívio da dormência desta espécie.Termos para indexação: Bowdichia virgilioides, germinação, escarificação, permeabilidade do tegumento. SEED DORMANCY OF PARICARANA TREE (Bowdichia virgilioides Kunth) -FABACEAE -PAPILIONIDAEABSTRACT -This study was carried out at the Seed Laboratory of Embrapa Roraima, with the objective to study the alleviation of seed dormancy of the Paricarana tree (Bowdichia virgilioides).The experimental design was a completely randomized design with four replications of 50 seeds each. The treatments were: mechanic scarification with water sandpaper; sulfuric acid -pa (5 and 10 minutes), ethanol (5 and 10 minutes) and control. The seeds were placed in plastic boxes on moist paper and incubated at 25 o C in a germinator. The parameters obtained were germination percentage, hard seed percentage, germination rate and percentage of normal seedlings at 30 days after sowing. The germinated seeds were counted daily for 30 days. Chemical scarification with sulfuric acid for 5 minutes was shown to be the most appropriate method for seed alleviation of this species.

The aim of this study was to verify the effect of different substrates, in the presence and absence of controlled-release fertiliser, on the growth and morphological quality of seedlings of Agonandra brasiliensis Miers ex Benth. & Hook.f., in the state of Roraima, Brazil. The experimental design was a 2 * 5 factorial scheme, with and without the addition of 1.0 g L-1 NPK 18-05-09 formulation controlled-release encapsulated fertiliser (Forth CoteR) and five substrates. The following were evaluated: shoot height (H), collar diameter (CD), increase in shoot length (IncH) and collar diameter (IncCD), shoot dry weight (SDW), root dry weight (RDW), total dry weight (TDW) and Dickson quality index (DQI). The use of NPK 18-05-09 formulation controlled-release fertiliser (Forth CoteR) in a medium-sand substrate is recommended for obtaining plants of Agonandra brasiliensis of greater robustness, balance of biomass distribution, and a high standard of quality. In the substrate composed of soil from the cerrado + carbonised rice husks - CRH + organic substrate (2:1:1), the addition of NPK 18-05-09 formulation Forth CoteR is not necessary to obtain Agonandra brasiliensis plants of good morphological quality. Substrate 3, composed of soil + CRH (3:1), with or without the addition of NPK 18-05-09 formulation Forth CoteR, is not recommended for producing plants of Agonandra brasiliensis, due to the slow development and reduced morphological quality of the plants.

Near Infrared (NIR) Spectroscopy technique combined with chemometrics methods were used to group and identify samples of different soy cultivars. Spectral data, collected in the range of 714 to 2500 nm (14000 to 4000 cm -1 ), were obtained from whole grains of four different soybean cultivars and were submitted to different types of pre-treatments. Chemometrics algorithms were applied to extract relevant information from the spectral data, to remove the anomalous samples and to group the samples. The best results were obtained considering the spectral range from 1900.6 to 2187.7 nm (5261.4 cm -1 to 4570.9 cm -1) and with spectral treatment using Multiplicative Signal Correction (MSC) + Baseline Correct (linear fit), what made it possible to the exploratory techniques Principal Component Analysis (PCA) and Hierarchical Cluster Analysis (HCA) to separate the cultivars. Thus, the results demonstrate that NIR spectroscopy allied with de chemometrics techniques can provide a rapid, nondestructive and reliable method to distinguish different cultivars of soybeans.

ResumoO objetivo nesse trabalho foi avaliar a qualidade fisiológica de sementes de pimenta em frutos de diferentes maturações, submetidas ao repouso pós-colheita nos frutos e o armazenamento das sementes. As sementes utilizadas foram colhidas em julho de 2009, de plantas cultivadas em casa de vegetação da área de transferência de tecnologia da Embrapa Roraima. O delineamento experimental utilizado foi inteiramente casualizado em esquema fatorial 3x2x2 com 4 repetições. Na colheita foram retirados frutos imaturos, intermediários e maduros, totalizando 90 frutos. Em parte dos frutos colhidos, a extração das sementes foi imediata e nos demais foram mantidas por 10 dias em temperatura ambiente a 25°C. A qualidade fisiológica das sementes foi avaliada quanto a germinação (plântulas normais e anormais) e velocidade de germinação. Os testes foram repetidos três meses após a colheita para avaliar o armazenamento. A colheita de frutos de pimenta no estádio intermediário (verde alaranjado) apresentou sementes com melhor qualidade fisiológica em relação às obtidas de frutos maduros (vermelho intenso) e frutos imaturos (verdes). A permanência das sementes no interior dos frutos, por dez dias, melhora a qualidade fisiológica das sementes obtidas de frutos colhidos precocemente (intermediário). As sementes extraídas dos frutos dez dias após a colheita apresentam melhor qualidade fisiológica aos três meses, do que as sementes extraídas logo após a colheita. Palavras-chave: Capsicum frutencens L, vigor, coloração de frutos AbstractThe objective of this study was to evaluate the physiological quality of pepper seeds as a function of maturity, presence of seeds in fruits and storage. Pepper seeds used for the study were collected in July 2009, from plants grown in greenhouse belonging to Embrapa Roraima sector of technology transfer. The experimental design was entirely randomized under a (3 x 2 x 2) factorial scheme. At harvest, immature, intermediate and ripe fruits were collected, totalizing 90 fruits. Extraction of seeds was immediate in part of fruits, and therest of fruits were left for 10 days at room temperature at 25 °C. Seed physiological quality was evaluated concerning germination, germination speed. The tests were repeated three months after harvest to assess storage aspects. According to results, the maturation stages that showed better physiological quality were the seeds originated from green orange color fruits (intermediate class) as compared to those obtained from ripe (intense red color) fruits and immature (green) fruits. Seed permanence within fruits for ten days improved its physiological quality among early harvested fruits (intermediate). Seeds extracted from fruits ten days after harvest showed better physiological at three months of storage, when compared to seeds extracted immediately after harvest.