Soil analysis is used to estimate nutrient availability, but nutrient concentrations are not always related to yield in most fruit plants, including grapevines. Thus, additional multivariate mathematical models, such as the compositional nutrient diagnosis (CND), which takes into account leaves nutrient concentration, and yield, can contribute to estimating critical levels or sufficiency bands of elements, as well as to detect deficiency and/or excess of nutrients. The aim of the present study was to establish CND standards, and the critical level and sufficiency band of nutrients, in the grapevine Vitis vinifera L., grown in a subtropical climate region. Leaves were collected in 81 vineyards in the Campanha Gaúcha do Rio Grande do Sul region, Southern Brazil, and analyzed for macro- and micro-nutrient concentration. The yield of each vineyard was assessed. Grapevine nutritional status was calculated through the CND method. CND-r2 indices were effective in establishing the nutritional status of grapevines for macro- and micro-nutrients as sub-optimal, excessive, or balanced. The CND methodology established the critical level and sufficiency bands of nutrients more accurately than the current recommendations for grapevines. Multi-nutrient associations were more effective than the single nutrient determination in defining the threshold of a given nutrient that can reduce grapevine yield.

Seed priming is a technique used to induce metabolic germination processes. Use of growth regulators in seed priming may facilitate increments in physiological processes during seed germination. The objective of this study was to evaluate the effect of priming and growth regulators on beet seed germination. The treatments were cultivar type (Early Wonder, Itapuã and Maravilha) and seed priming technique, which included a control (unconditioned seed) standard hydropriming (water) and a conditioning with salicylic, gibberellic and ascorbic acids, respectively. The treatments were defined by initially testing 0, 1, 2 and 4 mM ascorbic, gibberellic and salicylic acids. Before seed priming, imbibition seed curves were established to determine the optimal conditioning time. After conditioning, the germination, rate of germination, seedling length and seedling dry weight were evaluated. First, the appropriate dosage for conditioning was determined by using a completely randomized experimental design, with four replications per cultivar. Then, a 3 x 5 (cultivar x conditioning technique) factorial design was adopted. Whenever the results were significant by variance analysis, regression analysis was performed. Finally, Tukey's test was used to compare the means at P=0.05. Beet seed priming alters the potential of germination and is influenced by the cultivar and conditioning technique. Pretreatment with 1−2 mM ascorbic, gibberellic or salicylic acids, respectively, promotes beet seed germination, whereas at 1−3 mM, the growth of roots and shoots of beet seedlings is promoted. The most effective techniques to promote germination and growth of sugar beet seedlings were priming with water, salicylic acid or gibberellic acid. Key words: Beta vulgaris. Hydropriming. Gibberellic acid. Salicylic acid. Ascorbic acid. ResumoO condicionamento fisiológico é uma técnica que permite a ativação dos processos metabólicos e fisiológicos na germinação das sementes por meio da utilização de reguladores de crescimento. Desta forma, objetivou-se avaliar o efeito do condicionamento fisiológico de sementes de beterraba com reguladores de crescimento. Foram utilizadas três cultivares: Early Wonder, Itapuã e Maravilha, submetidas a cinco tipos de condicionamentos: testemunha (semente não condicionada) hidrocondicionamento padrão (água), condicionamento com os ácidos salicílico, giberélico e ascórbico. Para definição dos tratamentos, foram testadas doses de 0; 1; 2 e 4 mMol.L -1 dos ácidos. Previamente ao condicionamento, foram realizadas as curvas de embebição das sementes, para determinação do tempo ideal de condicionamento, logo após, as sementes foram avaliadas quanto à porcentagem e velocidade de germinação, comprimento e massa seca de plântulas. O delineamento experimental utilizado foi inteiramente casualizado com quatro repetições, separado para cada cultivar, determinando-se as dosagens adequadas. Na segunda etapa foi adotado esquema fatorial 3 x 5 (cultivares x tipo de condicionamento). Os resultados foram submetidos a análise ...

The aim of this study was to determine the effects of type of substrate and expanded polystyrene trays on the production of snapdragon seedlings. The experiment was completely randomized with a 3 x 2 factorial design (substrates x number of tray cells) and four replications. 'Baixa Sortida' snapdragon seeds, commercial substrate A (rice husk + vermiculite), commercial substrate B (Sphagnum + torrefied rice straw + perlite), A + B mixture (1:1) and expanded polystyrene trays with 72 and 128 cells were used. The characteristics evaluated were plant emergence rate, percentage of plant emergence at 14, 21, 28 and 35 days, number of leaves at 44 and 58 days after sowing, shoot height, root length and plant dry matter. The results showed that the substrates directly influenced the production of snapdragon seedlings. Seedling emergence and seedling development is favored by the mixture of the substrates A and B (1:1) as well as by the use of expanded polystyrene trays with 72 cells due to the higher volume available to the seedling.

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RESUMOA utilização de procedimentos eficientes para análise de sementes é fundamental para programas de controle de qualidade, auxiliando na escolha dos materiais de maior potencial para a produção de mudas, assim como para o monitoramento durante o armazenamento de sementes. O objetivo desta pesquisa foi identificar procedimentos adequados para o teste de envelhecimento acelerado para avaliação do vigor de sementes de Parapiptadenia rigida. Três lotes de sementes foram avaliados quanto ao teor de água e a germinação e vigor, por meio dos testes de condutividade elétrica, comprimento, massa fresca e seca de plântulas e com o teste de envelhecimento acelerado realizado com diferentes metodologias. Os resultados obtidos permitiram concluir que os testes de envelhecimento acelerado à 38°C por 24, 48 ou 72 horas e 41°C por 24 horas são eficientes na avaliação do vigor de sementes de Parapiptadenia rigida. PALAVRAS-CHAVE: angico, qualidade de sementes, tecnologia de sementes. ACCELERATED AGING TEST TO EVALUATE Parapiptadenia rígida SEED VIGORABSTRACT The use of efficient procedures for seed analysis is essential for quality control programs, helping to select the materials with the greatest potential for seedling production, as well as for monitoring during seed storage. The objective of this research was to identify appropriate procedures of accelerated aging test to evaluate Parapiptadenia rigida (Benth.) Brenan seed vigor. Parapiptadenia rigida seeds represented by 3 lots. Seed moisture content was measured and germination capacity were evaluated; seed vigor was evaluated by electrical conductivity, seedling length, fresh and dry seedling weight obtained after seedling length test and with different accelerated aging tests. Results showed that Parapiptadenia rigida seed vigor can be evaluated efficiently by accelerated aging tests, using combinations of 38 ° C for 24, 48 or 72 hours and 41 ° C for 24 hours.

RESUMOPara o cultivo da soja pode-se utilizar no tratamento de sementes formulados contendo microrganismos como Trichoderma spp. que é um fungo de solo conhecido como agente de controle biológico e promotor de crescimento vegetal. O objetivo do estudo foi avaliar a interferência de tratamentos com formulação líquida, formulação em pó e restrição hídrica e tempo de contato de sementes com Trichoderma spp. na emergência e no crescimento inicial da soja. Foram desenvolvidos dois experimentos em ambiente protegido. O delineamento experimental foi inteiramente casualizado em esquema fatorial 3 (formulados líquido e em pó e restrição hídrica) x 7 (tempo de contato com o fungo) + 1 (testemunha sem o fungo), com quatro repetições. O tratamento testemunha foi a semeadura das sementes de soja sem o contato com o fungo Trichoderma spp. Após cada período de contato (0h, 4h, 8h, 12h, 24h, 48h e 72h) as sementes foram semeadas em caixa tipo gerbox e em vasos contendo solo peneirado. As avaliações para o experimento em gerbox ocorreram aos sete dias e para os vasos aos trinta dias após a semeadura. Avaliaram-se: emergência, comprimento de parte aérea e de raiz e massa de matéria seca de parte aérea e de raiz. Os resultados encontrados para emergência e crescimento inicial de soja em gerbox foram diferentes dos encontrados para vasos, evidenciando que não se pode indicar o uso de uma formulação/tratamento ou um dos tempos de contato do fungo com as sementes, como sendo o ideal para o cultivo de soja. PALAVRAS-CHAVE: Controle biológico, Glycine max L., emergência.

Bioproducts can act on plant development in a positive, negative or neutral manner, as well as whether there is interaction of these products when used with other biological bioproducts, often used in soybeans such as Bradyrhizobium japonicum. The objective of this work was to evaluate the action of two trichoderma-based and two Bradyrhizobium japonicum-based bioformulates, combined or not, on variables in the early development of soybean plants, free of phytopathogens. The soybean cultivar Nidera 5909 was used and the treatments consisted of four commercial bioformulates, based on Trichoderma harzianum, Trichoderma sp. and two based on Bradyrhizobium japonicum, being tested in association and /or isolated for soybean seed inoculation. For the seedling emergence variable, there was no difference between the treatments tested. By analyzing the leaf variables such as leaf area, shoot length, fresh and dry shoot, the use of liquid B. japonicum results in higher averages compared to the other bioformulates. When evaluating root length, root surface area, root volume and root dry matter the use of bioformulated with Trichoderma sp. as active ingredient presented the highest averages. It was concluded that the use of Trichoderma sp. and Bradyrhizobium japonicum liquid in their isolated form, provide better initial development for soybean crop.

Direct onion sowing under soil tillage methods 1Onion production is conditioned to the adopted techniques during the cultivation. Sowing depth, soil preparation and cultivars are determinant factors for productivity to be increased. Two experiments were developed, the first with the objective of evaluating the effect of sowing depths and soil preparation methods on the germination and development of onion seedlings, while the objective of the second was to evaluate the productivity of onion cultivars as a soil preparation function. In experiment I, the split plot scheme was adopted, where the main plots consisted on soil tillage methods (total area and bed) and in the subplots, the sowing depths (0.5; 1.0; 1.5 and 2.0 cm), with six replicates. Experiment II was carried out in a split plot scheme, in which the main plots consisted on soil tillage methods (total area and bed) and in the subplots, such as onion cultivars (Itajubá, Rainha, Salto Grande, Ômega, Mulata and BR29), with four replicates. The 1.5 cm sowing depth provided greater speed of germination and plant stand. Raising beds offers the best initial seedling development. The onion cultivation under beds offers the highest vegetative development and productivity.