-The use of chemical seed treatment is an important tool in the protection of seedlings and has contributed to the increase of rice yield (Oryza sativa L.). The objective of this study was to evaluate the physiological quality and quantify the retention of chemical products in rice seeds treated with insecticide and fungicide coated with polymers. Six seed treatments were used: control, phytosanitary treatment and phytosanitary treatment and coating with the polymers, Florite 1127 ® and VermDynaseed ® polymers were efficient at retaining thiamethoxam in the rice seeds, preventing some of the active ingredients of the insecticide from being leached through the sand columns immediately after the simulated pluvial precipitation.

ResumoO objetivo do trabalho foi determinar a eficiência do tratamento químico de sementes de crambe com fungicida, inseticida e polímero na qualidade fisiológica e na produção de sementes. Sementes de crambe, cultivar FMS brilhante, foram submetidas aos seguintes tratamentos: T1 = Testemunha; T2 = Fungicida (F); T3 = Inseticida (I); T4 = Polímero (P); T5 = F + I; T6 = F + I + P; T7 = F + P, e T8 = I + P. O fungicida utilizado foi o Derosal 500 SC (i.a. Carbendazim), na dose de 3,0 ml kg -1 de sementes, e inseticida Cruiser 350 FS (i.a. Tiametoxam), na dose de 1,0 mL kg -1 de sementes. O polímero utilizado foi o Laborsan (resina sólida), na dose de 0,6 mL kg -1 de sementes. Após o tratamento, as sementes foram avaliadas em laboratório pelos testes de germinação, comprimento da raiz e parte aérea e massa seca de plântulas. Em solo, determinaram-se a emergência, o comprimento da raiz e da parte aérea e a massa seca de plântulas. Em vasos, foram avaliados a altura das plantas, o número de racemos por planta, o número de frutos por planta, o número de frutos por racemos e a produção de sementes. O tratamento de sementes de crambe com fungicida e/ou inseticida, associado a polímero, afetou o vigor em testes de laboratório e, em condições de solo, não afeta a germinação, a emergência de plântulas e a produção de sementes de crambe.Palavras-chave adicionais: polimerização; qualidade; revestimento. AbstractThe objective of this study was to evaluate the effects of treating crambe cultivar 'FMS brilhante' seeds with a fungicide, an insecticide, and a polymer on their physiological potential and productivity. The treatments were the following : T1 = control, T2 = Fungicide (F), T3 = Insecticide (I), T4 = Polymer (P), T5 = F + I, T6 = F + I + P, T7 = F + P, and T8 = I + P. The fungicide used was Derosal 500 SC (a.i. carbedazim) at the dose of 3.0 mL kg -1 of seeds and the insecticide was Cruiser 350 FS (a.i. Tiametoxam) at the dose of 1.0 mL kg -1 of seeds. Laborsan (solid resin) was the polymer used at the dose of 0.6 mL kg -1 of seeds. After the treatments the seeds were evaluated in the laboratory as to germination, seedling root and aerial part length, and the seedling dry weight. In vases, seedling height, the number of racemes per plant, number of fruits per plant, number of fruits per racemes, and seed production were evaluated. Seed treatment with fungicide and/or insecticide in association with a polymer affected seed vigor as evaluated in laboratory and, in the soil, had no effect on seed germination, seedling emergence and seed production.

-The objective of this study was to evaluate methods of overcoming dormancy, light regimens, temperature and depth of sowing variations in the physiological quality of Echium plantagineum seeds. The diaspores (agglutinated fruits from the seeds) were submitted to treatments using accelerated aging, potassium nitrate and gibberellic acid to overcome dormancy. A 7 x 2 factorial design was used to evaluate the temperatures (5, 10, 15, 20, 25, 30 and 35 °C) and light regimens (presence or absence of light). A 6 x 2 factorial design was used for sowing depth (0, 1, 2, 3, 4 and 5 cm) and soil coverage (presence or absence of straw). In all experiments, a completely randomized design with four replicates of 50 diaspores was used. The main evaluations were germination, first germination count, germination speed index and emergence. The seeds showed dormancy, which was overcome by the immersion of the diaspores in potassium nitrate and gibberellic acid. The ideal temperature for germination was 20 °C, showing greater germination in the presence of light, considered as preferentially positively photoblastic. The highest germination percentage occurred when the diaspores were positioned on the soil surface in the presence of straw.Index terms: gibberellic acid, purple flower, photoblastism, potassium nitrate, straw. Germinação de sementes de Echium plantagineum L. submetidas à superaçãoda dormência e variações na temperatura, luz e profundidade de semeadura RESUMO -Objetivou-se avaliar métodos de superação da dormência, regimes de luz, variações da temperatura e profundidade de semeadura na qualidade fisiológica de sementes de Echium plantagineum. Para isso, os diásporos (fruto concrescido das sementes) foram submetidos a tratamentos utilizando envelhecimento acelerado, nitrato de potássio e ácido giberélico para a superação da dormência. Utilizou-se um fatorial 7 x 2 para avaliar temperaturas (5, 10, 15, 20, 25, 30 e 35 °C) e regimes de luz (presença ou ausência). Já para profundidade de semeadura (0, 1, 2, 3, 4 e 5 cm) e cobertura de solo (presença ou ausência de palha) utilizou-se um fatorial 6 x 2. Em todos os experimentos foi adotado o delineamento inteiramente casualizado com quatro repetições de 50 diásporos. As principais avaliações realizadas foram germinação, primeira contagem de germinação, índice de velocidade de germinação e emergência. As sementes apresentam dormência, sendo superada pela imersão dos diásporos em nitrato de potássio e ácido giberélico. A temperatura ideal para a germinação foi 20 °C, apresentando maior germinação na presença de luz, sendo consideradas fotoblásticas positiva preferencial. A maior porcentagem de germinação ocorreu quando os diásporos foram posicionados na superfície do solo, na presença de palha.Termos para indexação: ácido giberélico, flor roxa, fotoblastismo, nitrato de potássio, palha.

This study evaluated the physiological quality and quantified the efficiency of polymer in reducing the loss of phytosanitary products by leaching from soybean seeds of different diameters and in different treatments. Two lots of seed and two types of treatments were tested: polymers associated with seed treatment, and polymer application in layers after the seed treatment. For that, the following treatments were analyzed: Control= no seed treatment; Treat+pol= seed treatment + polymers in the mix; Treat/pol= seed treatment + polymers applied in layers; Treat= seed treatment. To evaluate seed treatment retention by the polymers, extraction equipment was employed and leaching of the active ingredient thiamethoxam was quantified. Evaluation of physical quality was conducted with tests of germination rate, first count, emergence rate, accelerated aging, seedling length, seedling dry mass and moisture content. Polymer application associated with seed treatment was efficient in reducing losses by leaching, reducing product loss by 20%. No significant differences in retention and physiological quality were found when different methods for polymer application were compared. Bigger seeds presented greater vigor, but the germination rate was unaffected.

Salicylic acid acts on several plant physiological processes. Therefore, the aim of this study was to determine if salicylic acid interferes on the physiological quality of common bean seeds soaked with different concentrations by testing two seed imbibition methodologies. Common bean seeds of the cultivars Fepagro 26 and Predileto were utilized. The seeds were soaked in solutions of salicylic acid with concentrations of zero, 250, 500, 750, 1,000, 3,000 and 5,000 μM. Seed imbibition occurred in two ways: (1) germination paper moistened with salicylic acid solutions, and (2) seed imbibition in salicylic acid solutions in plastic boxes for 24 hours and subsequent sowing on germination paper moistened with distilled water. The experiment was maintained in a germination incubator under 25 °C temperature and with constant light. The number of normal seedlings (first count), length, fresh and dry matter of seedlings were determined on the fifth day after sowing. Germination percentage was assessed nine days after sowing. The study was performed in a completely randomized design with four replicates and 50 seeds were used for each treatment. Regression analysis was performed for salicylic acid concentrations, with no comparison of cultivars and seed imbibition methods. Salicylic acid in concentrations up to 1,000 μM does not negatively affect the common bean seed germination of the cultivars Fepagro 26 and Predileto, using seed soaking for 24 hours and imbibition in the germination paper. Concentrations of salicylic acid up to 1,000 μM and seed imbibition for 24 hours do not affect the vigor (first count) of the two common bean cultivars.