Response of Lupinus bracteolaris seeds to pre-germinative treatments and experimental conditions

EnglishContextualization: Lupinus bracteolaris is a heliophite species that vegetates low lands, open slopes and sandstone hills. Knowledge gap: Despite the high rusticity and potential for covering poor soils, there is still no information to assist in the analysis of its seeds. Purpose: To determine pre-germinative treatments, substrate, temperature, luminosity and water intake in the vigor of Lupinus bracteolaris seeds. Methodology: Fruits were collected from 20 matrix plants, then the seeds were processed and submitted to the following tests: pre-germinative methods (six treatments at 25°C); substrates and temperatures (sand and paper at 20, 25 and 30°C); photoblast test (white light, diffuse-green light and continuous dark under 20°C) and the imbibition curve (control and scarification between sandpaper under 20°C). Evaluations: percentage of germination and formed seedlings, germination speed index, average germination time and seedling formation, using a completely randomized design. Results and conclusions: According to the analyzed variables, the results showed superiority for the pre-germinative treatment between sandpapers for 20 seconds. In addition, the substrate paper germibox and the temperature of 20°C were the most suitable during seed germination. The seeds of Lupinus bracteolaris were classified as neutral-photoblastic and without dormancy. portuguesContextualizacao: Lupinus bracteolaris e uma especie heliofita que vegeta campos baixos, taludes descobertos e morros areniticos. Lacuna de conhecimento: apesar da elevada rusticidade e potencial para cobertura de solos pobres, ainda nao ha informacoes que auxiliem na analise de suas sementes. Objetivo do estudo: determinar tratamentos pre-germinativos, substrato, temperatura, luminosidade e absorcao de agua no vigor de sementes de Lupinus bracteolaris. Metodologia: Coletaram-se frutos em 20 plantas matrizes, posteriormente realizou-se o beneficiamento das sementes e as submeteram aos testes: metodos pre-germinativos (seis tratamentos sob 25°C); substratos e temperaturas (areia e papel sob 20, 25 e 30°C); teste de fotoblastia (luz branca, luz verde difusa e escuro continuo sob 20°C) e a curva de embebicao (controle e escarificacao entre lixas sob 20°C). Avaliacoes: percentual de germinacao e de plântulas formadas, indice de velocidade de germinacao, tempo medio de germinacao e de formacao de plântulas, utilizando-se delineamento inteiramente casualizado. Resultados e conclusoes: De acordo com as variaveis analisadas, os resultados evidenciaram superioridade para o tratamento pre-germinativo entre lixas durante 20 segundos. Alem disso, o substrato papel germibox e a temperatura de 20°C foram os mais adequados durante a germinacao das sementes. As sementes de Lupinus bracteolaris foram classificadas como fotoblasticas neutras e sem dormencia.