A secagem de sementes de pepino é etapa obrigatória no seu beneficiamento, bem como o armazenamento para conquistar mercados competitivos e melhores oportunidades de preços. Portanto, o objetivo com este trabalho foi o de avaliar o desempenho fisiológico e bioquímico durante a secagem e armazenamento de sementes de pepino. A cultivar utilizada foi o híbrido de pepino Ômega comercializado pela Agristar Ltda. As sementes foram lavadas e secadas em temperatura ambiente de 25 ºC, 35 ºC e 45 ºC até atingir grau de umidade de 7%. As sementes foram embaladas em sacos de papel multifoliado e armazenadas em condições de ambiente não controlado. As avaliações da qualidade foram realizadas aos 0, 3, 6, 9 e 12 meses pelos testes de germinação, primeira contagem, condutividade elétrica e emergência de plântulas em bandeja. Avaliaram também as atividades enzimáticas de superóxido dismutase, catalase, esterase, lipoxigenase, isocitrato liase e proteína LEA, e por fim o teste de sanidade. A secagem de sementes de pepino, em temperatura ambiente, e a 35 ºC resulta em sementes de melhor qualidade. Ocorre redução da qualidade fisiológica das sementes e da atividade da proteína LEA a partir de seis meses de armazenamento, independente da temperatura de secagem.

Considering the scarce information on nutrient extraction by plants for seed production within vegetable crops, as well as the effect of fertilization over extraction, studying nutrient accumulation in different plant parts under varied fertilization rates is necessary. This study aimed to evaluate the influence of phosphate rates on macronutrient accumulation in cauliflower plants during seed production. Five phosphate rates were studied (0, 300, 600, 900 and 1200 kg/ha P₂O₅), in a randomized complete block design, with four replications. Accumulation of nutrients in the different plant parts was evaluated at the end of the cycle (vegetative and reproductive, the latter divided in seeds and inflorescence). Data were submitted to analysis of variance and regression. Considering only the seeds, a quadratic effect was obtained for the accumulation of all macronutrients, with maximum estimated for rates between 858 and 952 kg/ha P₂O₅. Considering the whole plant (total accumulation), a linear increase for P, Ca and S was obtained the higher the P₂O₅ rates, while the effect was quadratic for N, K and Mg accumulation. The total nutrient accumulation descending order was: K>N>Ca>S>P>Mg, and considering only the seeds was: N>S>K>P>Ca>Mg, S being highlighted as the second most accumulated nutrient in the seeds.

The authors evaluated the effects of doses of organic compost on the production and accumulation of macronutrients in endive plants in two areas with different fertility levels. The experiments were carried out at Fazenda Experimental São Manuel, located in the municipality of São Manuel, São Paulo State, Brazil. The study was carried out in a completely randomized design with seven treatments, six doses of organic compost (0, 35, 70, 105, 140 and 175 t/ha) and one additional treatment with inorganic fertilizer (N-P-K 4-14-8) and four replicates. In both areas, when the dose of organic compost was increased, the authors noticed a linear increase in fresh matter weight, number of leaves and plant height. In high-fertility area, compared to control (dose 0), using the highest dose (175 t/ha), the authors observed an increase of 280, 58 and 101% in fresh matter weight, number of leaves and plant height, respectively. For dry weight, we observed a linear increase in low fertility area and quadratic effect in high fertility area, with maximum estimated dry matter of 22.26 g applying 144 t/ha of organic compost. The nutrient accumulation was proportional to dry matter, with a linear increase in low fertility area and quadratic effect in high fertility area. The decreasing order of accumulated nutrients was K>N>Ca>P>S>Mg, with the highest values, in high fertility area, of 1,269, 471, 185, 91, 53 and 35 mg/plant, respectively, for doses varying from 121 to 158 t/ha.

There are researches with calcium to produce the cauliflower inflorescence, but for seeds production no studies were found, this element is fundamental for the fixation of the floral buds and in the production and quality of seeds. The objective was to evaluate the effect of foliar application of calcium on different phenological stages of cauliflower plants in seed production and quality. Eleven treatments were evaluated, varying the number (1 to 4) of calcium (6 g L-1 of calcium chloride) applications and the phenological stages (E1 = floral stem with 30 cm length, E2 = opening of the first flowers; E3 = formation of first siliques; E4 = 50% of silique formed), resulting: T1 = control without application of Ca; T2 = E1; T3 = E1 + E2; T4 = E1 + E2 + E3; T5 = E1 + E2 + E3 + E4; T6 = E2; T7 = E2 + E3; T8 = E2 + E3 + E4; T9 = E3; T10 = E3 + E4; T11 = E4. The results showed a higher seed production per plant in treatments T10 (E3 + E4) and T11 (E4) with 42 and 48 g per plant, and a higher number of seeds per plant, with 12,379 and 12,978, respectively, compared to the control (T1): 23 g and 5,725 seeds per plant. Calcium applications in different phenological stages did not influence the physiological quality (germination and vigor) of cauliflower seeds of cultivar 'Piracicaba Precoce'. Application of these treatments in other cultivars is promising for further studies.

Due to the scarcity of information related to the effect of fertilizers on production and quality of vegetable seeds, mainly on species which present an increase in the cycle, like cauliflower, more studies are necessary about the influence of nutrients rates which provide high production of high-quality seeds. This research aimed to evaluate the influence of rates of phosphorus (P) on the production and quality of cauliflower seeds. Five rates of phosphorus were studied (0, 300, 600, 900 and 1200kg ha-1 of P2O5), in a randomized complete block design, with four replications. Production and quality (weight of a thousand seeds, germination test, first count of germination test and emergence in substrate) of the seeds and soil chemical characteristics were evaluated. The higher the rate of phosphorus, the higher P content in the soil and values of sum of bases, cation exchange capacity and saturation of bases were observed at the end of the cycle. Seed quality was not affected by P fertilization, with the exception of the weight of a thousand seeds which was adjusted to a linear model. For seed production quadratic effect was obtained. The highest weight of seeds per plant was estimated for the rate of 862kg ha-1 of P2O5.

Producing seeds in the organic production system still requires a lot of information regarding the fertilization and nutritional requirements. Thus, the objective of this study was to determine the dry mass and macronutrient accumulation curve in lettuce for seed production, aiming at cultivation in an organic system. The treatments consisted of two phosphorus doses (320 and 800 kg ha⁻¹ of P₂O₅, Yoorin^® thermophosphate source). The crisp lettuce plants, cultivar Solaris, were collected at eight stages (0, 14, 28, 42, 56, 70, 84, and 98 days after transplanting—DAT) for an analysis of the proposed characteristics. A nonlinear sigmoid regression curve was fitted and the results demonstrated continuous plant growth, accompanied by a gradual increase in dry matter throughout the experimental period, regardless of the phosphorus dose studied. The vegetative part of the lettuce plant shows slow initial growth, followed by acceleration up to the beginning of flowering (70 DAT), and stabilization after this period. The reproductive part of the lettuce plant begins to grow from 56 DAT, increasing the daily nutrient demand until the end of the seed maturation and harvest at 98 DAT. The dose of 800 kg ha⁻¹ of P₂O₅, the lettuce plant accumulated 1527.7, 308.2, 2922.6, 1658.4, 416.0, and 197.6 mg per plant of N, P, K, Ca, Mg, and S, respectively. The dose of 320 kg ha⁻¹ of P₂O₅, the lettuce plant accumulated 1743.1, 256.9, 2575.7, 1210.2, 358.8, and 185.5 mg per plant of N, P, K, Ca, Mg, and S, respectively. The greatest demand for nutrients in the plant occurred between 55 and 88 DAT.