André Pich Brunes

Desempenho de sementes de soja sob deficiência hídrica: rendimento e qualidade fisiológica da geração F1

Seed vigor interferes significantly in tolerance to water deficit and seed yield. The objective of this study was to evaluate the influence of water stress on yield and physiological quality of seeds produced in the F1 generation. The study was conducted in a greenhouse using seeds of the cultivar M-SOY 8008RR, sown in pots with capacity of 15kg of soil A1 horizon of a Eutrophic Haplic Planosol Solodicin . The experimental design was completely randomized in a 2x2 factorial, with and without water deficit of 1st to 10th day after emergence and seed vigor level: high and low, totaling four treatments with five replicates. The variables analyzed were dry mass of shoots and leaf area at 10, 20, 30 and 40 days after emergence, yield and physiological quality through germination, first count, accelerated aging and weight of a thousand seeds of seeds in the F1 generation. The use of seed provides high force increases over 15% yield with respect to the use of low seed vigor. Water deficit from the 1st to the 10th day after emergence does not interfere in the yield and seed quality of the F1 generation, either for seeds of high and low vigor.

Desempenho de sementes de arroz tratadas com zinco, boro e molibdênio

The objective of this study was to assess physiological quality of seeds and the initial growth of lowland rice seedlings, cv. PUITA INTA-CL, treated with a product based on Zinc, Boron and Molybdenum. The following dosages of product were used: 0 (control), 50, 100, 150 and 200 mL.100 kg-1 seed. A completely randomized experimental design was used, with 10 treatments and four replications. Physiological quality of seeds was assessed by following tests: germination; first count of germination; and length and dry phytomass of seedlings. The initial growth was assessed at 7, 14, 21, 35, and 42 days after emergence (DAE) through plant height, leaf area and dry phytomass of aerial parts and roots. It was concluded that the treatment of rice seeds with the product containing Zinc, Boron and Molybdenum up to the dosage tested of 200 mL.100 kg-1 seed does not influence germination, first count of germination, and the dry phytomass of aerial parts and roots; however, negatively influences seedling length. In addition, it also promotes greater plant height, higher leaf area, higher production of dry phytomass of seedlings, and increase on the growth rate, until 42 DAE.

Tratamento de sementes de arroz com silício e qualidade fisiológica das sementes

The use of silicon is from environmental point of view a clean technology which can confer several benefits to plants. The aim of this study was to evaluate the effect of different doses and sources of silicon as seed treatment, the physiological quality of treated seed produced from plants grown from seeds coated with silicon. The experimental design was a randomized block in factorial 3x5 (silicon sources: Kaolin, Ladle Furnace Slag and Ash Bark Rice, Si doses: 0, 30, 60, 90, 120 g per100 kg seeds) with four replications. The rice cultivar used was BRS Querencia. The physiological quality of seeds was evaluated by the following tests: germination, first count, cold test, accelerated aging, shoot length and root length. Treatment of rice seeds with silicon does not adversely affect the physiological quality of treated seeds. Silicon application via seed treatment provides the production of rice seeds with greater vigor.

Seedling length in wheat determined by image processing using mathematical tools

Seed vigour is determined by a series of laboratory tests, many of these laborious and time-consuming. In view of this, the present study aimed to compare the determination of seedling length in wheat using image processing, with the traditional method, as well as the ability of the method to determine seed vigour. The experimental design was completely randomised, with five replications comprising a single-factor experimental scheme. The data were analysed for normality by the Shapiro-Wilk test and variance analysis using ANOVA at 5% probability. The response variables were correlated using Pearsons test, and the methodologies for determining the length of the shoots and roots, by measuring with a graduated rule and by image processing, were compared using the F-test at 5% probability. To compare mean values between cultivars, Tukeys test at 5% probability was used. The length of the shoots and roots of wheat seedlings, determined by image processing using the Matlab ® mathematical tool, is efficient in separating the cultivars

Accelerated aging test in amaranth (Amaranthus cruentus L.) seeds.

The use of vigor tests for assessing seed lot quality is an important tool for production and commercialization. However, research on evaluating the quality of amaranth seeds is still scarce. The objective of this work was to evaluate procedures for conducting the accelerated aging test, aiming at the identification of different levels of vigour among lots of amaranth (Amaranthus cruentus L.) seeds cultivar BRS Alegria. Five seed lots were used and submitted to tests of germination, first count of germination, seedling emergence and accelerated aging, using the aging periods of 24, 48 and 72 hours and adopting the traditional methodology with water and the use of saturated (40g NaCl in 100mL of water) and unsaturated (11g NaCl in 100mL of water) sodium chloride (NaCl) solution. The accelerated aging test at 41oC and periods of 24, 48 and 72 hours of conditioning saturated NaCl solution allowed the stratification of the lots at vigour levels, similar to the results obtained by the seedling emergence test and the first count of germination. The accelerated aging test, using saturated saline solution (40g NaCl in 100mL of water) for 24 hours at 41°C, is therefore suitable for evaluating the physiological potential of amaranth seeds.

TRATAMENTO DE SEMENTES DE SOJA COM ZINCO: EFEITO NA QUALIDADE FISIOLÓGICA E PRODUTIVIDADE

Objetivou-se avaliar o efeito do tratamento de sementes de soja com zinco na qualidade fisiologica das sementes tratadas e produzidas bem como nas caracteristicas agronomicas. O delineamento experimental adotado foi inteiramente casualizado, em esquema fatorial 2 X 5 (Lotes: A e B; e doses da fonte: 0, 2, 4, 6 e 8 mL kg-1 de semente). Apos o tratamento das sementes, foi analisada a qualidade fisiologica das mesmas, avaliadas pelo teste de germinacao, primeira contagem de germinacao, teste frio, envelhecimento acelerado, comprimento da parte aerea e de raiz. Na sequencia foi realizada a semeadura das sementes tratadas em vasos, conduzindo o experimento ate a fase de maturacao de campo. Apos a colheita, foram avaliados as caracteristicas agronomicas e a qualidade fisiologica das sementes produzidas. As caracteristicas agronomicas foram avaliadas atraves do numero de sementes por planta, numero de legumes por planta, peso de sementes por planta. A qualidade das sementes produzidas foi avaliada pelos testes acima citados mais o teste de emergencia a campo. O tratamento das sementes de soja nas doses entre 2 a 6 mL kg de sementes-1 apresentou os melhores resultados para a qualidade fisiologica e caracteristicas agronomicas. O numero de sementes por planta, numero de legumes por planta e peso de sementes por planta apresentam incrementos com o aumento das doses de zinco. O tratamento das sementes de soja com zinco nao influencia a qualidade fisiologica das sementes produzidas. Os lotes apresentam comportamentos diferentes em resposta ao tratamento das sementes com zinco.

Crescimento de plântulas de aveia branca submetidas ao estresse salino

The cultivation of white oat in succession to irrigated rice is considered a viable alternative, mainly because of their added value and for their restorative characteristics of the soil, though their productive potential can be reduced considerably because of the soil salinization, being very important to determine salt concentration tolerated by different white oat cultivars.The objective is to evaluate, oat cultivars recommended for the state of Rio Grande do Sul under different salt concentrations in seed germination and early growth. The experimental design was completely randomized factorial 2X5, with four replications, (cultivars Barbarasul and Chiarasul, salt concentration and levels 0, 25, 50, 75 and 100 mM NaCl per liter of water). The physiological seed quality was evaluated in the laboratory by germination, first count of germination, length of shoot and root dry weight of shoot and root. Based on the results we can conclude that: germination and seedling growth of oat cultivars and Barbarasul Chiarasul are 1 Eng°s Agros, Discente de Doutorado em Ciência e Tecnologia de Sementes, Universidade Federal de Pelotas UFPEL, Pelotas, RS. E-mail: beldar_brunes@msn.com; danielfonseca30@yahoo.com.br; lizandro_cicilianotavares@yahoo.com.br 2 Licenciado em Ciências Agrícolas, Discente de Doutorado em Ciência e Tecnologia de Sementes, UFPEL, Pelotas, RS. E-mail: cassyo.araujo@yahoo.com.br 3 Enga Agra, Profa Dra do Programa em Pós-Graduação em Ciência e Tecnologia de Sementes, UFPEL, Pelotas/RS. E-mail: lilianmtunes@yahoo.com.br 4 Prof. Dr. do Programa em Pós-Graduação em Ciência e Tecnologia de Sementes, UFPEL, Pelotas, RS. E-mail: francisco.villela@ ufpel.edu.br * Autor para correspondência

Effect of acetic acid on rice seeds coated with rice husk ash

O alagamento do solo para o cultivo do arroz irrigado promove condicoes anaerobias que favorecem a producao de acidos orgânicos de cadeia curta, como o acido acetico, os quais podem ser toxicos para a cultura. O objetivo foi avaliar o efeito do acido acetico em sementes de arroz recobertas com cinzas de casca de arroz. Foi utilizado o delineamento inteiramente casualizado, usando-se o esquema fatorial 2 x 5 x 5, sendo dois cultivares (IRGA 424 e BRS Querencia), cinco doses de recobrimento com cinzas de casca de arroz (0, 2, 3, 4 e 5 g.kg-1 de semente) e cinco concentracoes de acido acetico (0, 3, 6, 9 e 12 mM), totalizando 50 tratamentos com quatro repeticoes. Os testes realizados foram: primeira contagem da germinacao, germinacao, comprimento da parte aerea, comprimento da raiz, fitomassas secas da parte aerea e da raiz. Conclui-se que o recobrimento de sementes de arroz com cinzas de casca de arroz ate 5 g.kg-1 de semente nao influencia o desempenho de sementes de arroz dos cultivares IRGA 424 e BRS Querencia, quando submetidas a concentracoes de acido acetico ate 12 mM. A presenca do acido acetico, em substratos para germinacao de sementes, reduz o vigor e a viabilidade de sementes de arroz dos cultivares IRGA 424 e BRS Querencia, alem de reduzir o desenvolvimento de plântulas, afetando, principalmente, as raizes da BRS Querencia.