34 research outputs found
VIGOR TESTS ASSOCIATION AS AN ALTERNATIVE FOR PRECISE AND EFFICIENT ASSESSMENT OF MAIZE SEED QUALITY
CHARACTERIZATION AND EARLY SELECTION OF SILK BLOSSOM ( CALOTROPIS PROCERA ) GENOTYPES WITH FORAGE POTENTIAL
Aplicação de dessecantes na cultura de soja: teor de umidade nas sementes e biomassa nas plantas Application dissecants in soybean: degree of humidity in the plant's seeds and biomass
Os objetivos deste trabalho foram avaliar a eficácia dos dessecantes e determinar a melhor época de aplicação na cultura de soja. O delineamento experimental utilizado foi em blocos casualizados, estando os tratamentos dispostos em esquema fatorial 3x3 e 4x4 de produtos (dessecantes) e épocas de aplicação, nos anos agrícolas 1996/97 e 1997/98, respectivamente. Os dessecantes utilizados foram: paraquat, diquat e paraquat + diquat em 1996/97 e paraquat, diquat, paraquat + diquat e glufosinato de amônio em 1997/98, respectivamente nas dosagens de 0,4, 0,3 e 0,2 + 0,15; e 0,4, 0,3, 0,2 + 0,15 e 0,4 kg i.a. ha¹. Como épocas, foram realizadas três aplicações em 1996/97 e quatro em 1997/98, com intervalos de cinco dias a partir do estádio R6. Após análise e interpretação dos resultados, concluiu-se que os dessecantes foram eficazes na dessecação e que o teor de umidade das sementes entre 50 e 60%, as plantas com baixa incidência de vagens amarelas e marrons e a relação peso de biomassa verde de vagens/biomassa verde total de cerca de 0,5 foram características marcantes na determinação da melhor época de aplicação dos dessecantes.<br>The objectives of this work were to evaluate dissecant efficiency and determine the best application time for soybean crop. The experimental design was randomized blocks in factorial schemes 3x3 and 4x4 (dissecants x application time), in 1996/1997 and 1997/1998, respectively. The dissecants applied were: paraquat, diquat and paraquat + diquat in 1996/97 and paraquat, diquat, paraquat + diquat and ammonium glufosinate in 1997/1998, respectively, in the following doses: 0.4; 0.3 and 0.2 + 0.15 and 0.4; 0.3; 0.2 + 0.15 and 0.4 kg a.i. ha-1 Three application times were used in 1996/1997 and four in 1997/1998, with intervals of five days starting from stage R6. Analysis and interpretation of the results allowed to conclude that the dissecants were efficient and that seed moisture between 50 and 60%, plants with low incidence of yellow and brown beans and the relation green biomass weight/total green biomass weight of the plants around 0.5 were the main characteristics for determining the best times for dissecant application
Pruebas de vigor y calidad fisiológica de semillas de soja Vigor tests and physiological quality of soybean seeds
El objetivo de este trabajo fue estudiar las alteraciones producidas por el deterioro en semillas de soja (Glycine max L. Merrill) utilizando diferentes pruebas de vigor. Se utilizaron semillas de soja de diferentes cultivares en 1997 y 1998, las cuales fueron sometidas a la prueba de germinación y diferentes pruebas de vigor: envejecimiento acelerado; conductividad eléctrica; deterioro controlado y tetrazolio. El deterioro controlado en semillas con 22% de humedad mostró ser un mejor indicador de la disminución del vigor de la semilla de soja que el envejecimiento acelerado. La conductividad eléctrica en semillas individuales podría ser considerada una buena prueba de vigor para detectar alteraciones producidas en las membranas citoplasmáticas en un estadio temprano del deterioro de las semillas. La clasificación de la viabilidad y el vigor a través de la prueba de tetrazolio está dada por el lugar donde se produce el daño y no por el tipo de daño que sufre la semilla.<br>The objective of this work was to study soybean (Glycine max L. Merrill) seed alterations produced by deterioration using different vigor tests. Soybean seeds of different cultivars were used in 1997 and 1998, which were submitted to standard germination test and the vigor tests: accelerated aging; electric conductivity; controlled deterioration and tetrazolium. The controlled deterioration with an elevation of the seed humidity to 22%, showed to be a better indicator of the diminishing of soybean seed vigor than the accelerated aging. The electric conductivity in individual seeds would be considered a good vigor test to detect the alterations produced in the cytoplasmic membranes in an early stage of the seed deterioration. The tetrazolium test by the evaluation of the different kinds of injuries suffered by the seeds, depends on the place where the seed is damaged not on the kind of injury suffered by the seed