Qualidade fisiológica de sementes de leiteiro (Peschiera fuchsiaefolia) em função do estádio de maturação dos frutos
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Data
2004-12-01
Autores
Martins, D. [UNESP]
Martins, C.C. [UNESP]
Carbonari, Caio Antonio [UNESP]
Terra, M.A. [UNESP]
Título da Revista
ISSN da Revista
Título de Volume
Editor
Sociedade Brasileira da Ciência das Plantas Daninhas
Resumo
O leiteiro (Peschiera fuchsiaefolia) é uma infestante de pastagens de importância para as regiões Sudeste e Centro-Oeste do Brasil, cuja dispersão ocorre por sementes. Com o objetivo de avaliar a qualidade fisiológica das sementes de leiteiro, em função do estádio de maturação e armazenamento dos frutos, foram colhidos frutos em cinco regiões diferentes, constituindo cinco acessos: lote 1-Vitoriana/SP, lote 2-Botucatu/SP, lote 3Bauru/SP, lote 4-São Manuel/SP e lote 5-São Pedro/SP. Cada lote de sementes foi avaliado individualmente, seguindo-se o delineamento estatístico inteiramente casualizado, com os tratamentos dispostos em esquema fatorial 2x4, sendo dois períodos de armazenamento dos frutos (0 e 7 dias após colheita) e quatro estádios de maturação (verde-oliva, verde-limão, alaranjado-fechado e alaranjado-aberto). A polpa dos frutos foi retirada e as sementes extraídas mediante fricção em peneira sob água corrente. As sementes foram colocadas para germinar a 30 ºC com 8 h de luz, sendo as contagens realizadas semanalmente até os 42 dias do início do teste. Os resultados dos testes da primeira contagem de germinação, IVG e condutividade elétrica mostraram que o vigor das sementes foi superior em frutos colhidos nos estádios finais de maturação e que, de modo geral, o armazenamento dos frutos prejudicou a qualidade das sementes.
Peschiera fuchsiaefolia is a pasture weed in southern Brazil whose dispersion occurs by seeds. The objective of this research was to evaluate the physiological quality of P. fuchsiaefolia at fruit maturation stages and storage periods. This experiment was carried using fruit seeds harvested in 5 different regions: lot 1-Vitoriana/SP, lot 2-Botucatu/SP, lot 3Bauru/SP, lot 4-São Manuel/SP and lot 5-São Pedro/SP. The experimental design was completely randomized with the treatments arranged in a factorial design 2 x 4, being two storage periods (0 and 7 days after harvest) and four fruit maturation stages [dark green (5GY 4/4), green (5GY 6/8), dark orange (5YR 5/10) and light orange (2,5Y 8/12)]. The fruit pulp was removed and the seeds were extracted by friction in sieve under running water. The seeds were put to germinate at 30 ºC during 8 hours of light. Germination was weekly evaluated up to 42 days after sowing. Seed vigor was determined by first germination counting, index of germination speed and electrical conductivity. Seed vigor was greatest in fruits harvested at the final stage of maturation. Storage affected seed quality.
Peschiera fuchsiaefolia is a pasture weed in southern Brazil whose dispersion occurs by seeds. The objective of this research was to evaluate the physiological quality of P. fuchsiaefolia at fruit maturation stages and storage periods. This experiment was carried using fruit seeds harvested in 5 different regions: lot 1-Vitoriana/SP, lot 2-Botucatu/SP, lot 3Bauru/SP, lot 4-São Manuel/SP and lot 5-São Pedro/SP. The experimental design was completely randomized with the treatments arranged in a factorial design 2 x 4, being two storage periods (0 and 7 days after harvest) and four fruit maturation stages [dark green (5GY 4/4), green (5GY 6/8), dark orange (5YR 5/10) and light orange (2,5Y 8/12)]. The fruit pulp was removed and the seeds were extracted by friction in sieve under running water. The seeds were put to germinate at 30 ºC during 8 hours of light. Germination was weekly evaluated up to 42 days after sowing. Seed vigor was determined by first germination counting, index of germination speed and electrical conductivity. Seed vigor was greatest in fruits harvested at the final stage of maturation. Storage affected seed quality.
Descrição
Palavras-chave
planta daninha, germinação, pastagem, weed, germination, pasture
Como citar
Planta Daninha. Sociedade Brasileira da Ciência das Plantas Daninhas , v. 22, n. 4, p. 539-544, 2004.