摘要：Abstract In nature, allelopathic substances are likely to influence the germination of seeds. Callistemon viminalis, Tephrosia vogelii, Senna spectabilis, Cupressus lusitanica, and Polyscias fulva are found around some tomato culture fields in Cameroon. These plants may produce allelochemicals that can influence tomato seed germination and seedling characteristics. Methanol extracts and their fractions were prepared from leaves of these plants and tested on seed germination rate, shoot diameter, root and stem lengths, and vigor index of seedlings. The tested substances did not significantly (p > 0.05) affect the seed germination rate. Aqueous extracts of T. vogelii, C. lusitanica, and C. viminalis exerted the highest inhibition on seed germination while methanol extract, hexane, and ethyl acetate fractions of all the plants induced significant increases in diameters of seedlings. Aqueous extracts were effective on the stem length. All treatments generally reduced the root length. Methanol extracts induced significantly higher vigor indices (p < 0.05).
关键词：Allelopathy ; germination ; vigor index ; extract ; fractions
