Nilson Matheus Mattioni

Teste de condutividade elétrica em sementes de aveia preta

Determining physiological potential in black oats seeds shows some difficulties due to the lack of standardized tests. On the other hand, the measuring the electric conductibility of the seed immersion solution can be a fast method, that can be applied to oats seeds, because it indicates the integrity of cellular membranes, and gives us, indirectly, the information about the physiological quality of the seeds. The objective of this study was to evaluate the effect of the number of seeds and the imbibition time over the electrical conductivy of the solution, in the evaluation of the strength of oats seeds with and without shell. The experiment was conducted using three lots of common oats seeds. The test was made at 25o C, imbibition testing times of 4, 8 and 16 hours, with 25 and 50 seeds. The treatments constituted a factorial, using a complete randomized design with four repetitions. The use of 25 black oat seeds without shell in 75mL distilled water, with an imbibition time of eight hours, was enough to stratify the lots in different strength levels.

Teor de proteína e qualidade fisiológica de sementes de arroz

O trabalho teve como objetivo avaliar o teor de proteina como elemento auxiliar na determinacao da qualidade fisiologica de sementes de arroz, alem de correlaciona-la com a emergencia em campo. Foram utilizados seis lotes de sementes de arroz, sendo tres lotes da cultivar IRGA 417 e tres lotes da cultivar IRGA 422 CL, submetidas ao conjunto de testes, para caracterizar o potencial fisiologico dos lotes: germinacao, primeira contagem de germinacao, envelhecimento acelerado, frio sem terra, comprimento de plântula e massa seca de plântula. Apos a determinacao da qualidade inicial dos lotes foi aplicado novo conjunto de testes, composto pelo teor de proteina bruta e pelas avaliacoes das plântulas e plantas em campo. Conclui-se que o teor de proteina bruta e capaz de identificar diferencas entre lotes de arroz, em funcao da qualidade das sementes, e correlacionar-se com a emergencia em campo, quando ocorre em condicoes desfavoraveis; portanto, trata-se de uma determinacao promissora para associacao aos testes convencionais a fim de avaliar o potencial fisiologico das sementes de arroz.

VARIABILIDADE ESPACIAL DA PRODUTIVIDADE E DA QUALIDADE DAS SEMENTES DE SOJA EM UM CAMPO DE PRODUÇÃO 1

Seed production fields of soybean ( Glycine max L. Merrill) are subject to various factors that influence the final seed quality but which do not always act uniformly. The objective of the present study was to determine the spatial variability of the productivity and quality of soybean seeds in a production field using precision farming. Seeds were collected following a grid of one point per hectare, georeferenced, with four sub-samples, totaling a harvested area of 16 m 2 per point, which were used to estimate productivity after being weighed. Seed sizes were determined by the retention test in sieve sizes of 5.5, 6.5 and 7.5 mm and seed physiological

Physiological quality of soybean seeds treated with different spray volumes

The aim of this study was to define the influence of treatments with different seed spray volumes and their effects on the physical and physiological quality. The soybean seeds from cultivars NA 5909 RG and BMX Potencia RR were used and three lots of each cultivar were selected in sieves of different diameters (5.5; 6.0 and 6.5 mm). The treatments consisted of different seed volumes: 1) non-treated seeds; 2) 600 mL.100 kg of seeds-1; 3) 800 mL.100 kg of seeds-1; 4) 1000 mL.100 kg of seeds-1; 5) 1200 mL.100 kg of seeds-1; 6) 1400 mL.100 kg of seeds-1. The physical parameters evaluated were mechanical damage, water content and variations in the length and width of the seeds. The physiological seed quality was determined by germination, first count germination, length and dry weight of seedlings, field emergence and emergence speed index tests. In terms of use of the product in liquid form, it is possible to use the treatment in spray volumes up to 1400 mL.100 kg seed-1, regardless the cultivar or seed size and without damaging the soybean seeds physically and physiologically.

Comportamento de hidratação e qualidade fisiológica das sementes de arroz

O trabalho teve como objetivo verificar a relacao existente entre o comportamento da curva de hidratacao de sementes de arroz e sua qualidade fisiologica. Foram utilizados seis lotes de sementes de arroz, sendo tres da cultivar IRGA 417 e tres da cultivar IRGA 422 CL, inicialmente submetidos a testes para caracterizar o potencial fisiologico dos lotes: germinacao, primeira contagem de germinacao, envelhecimento acelerado, frio sem terra, condutividade eletrica, comprimento de plântula, massa seca de plântula e emergencia em campo. Posteriormente, foi determinada a curva de hidratacao das sementes de cada lote. Conclui-se que a qualidade fisiologica afeta o teor de agua alcancado pelas sementes de arroz durante a hidratacao, e nas sementes menos vigorosas notam-se menor velocidade de hidratacao e grau de umidade, comparativamente as sementes de mais vigor.