Sources and concentrations of smoke-water on the seed germination and seedling vigor of tomato

Abstract

Smoke and smoke diluted in water, known as smoke-water, can be used to promote both seed germination and seedling vigor of several wild and cultivated species. The objective of this study was to assess the effectiveness of smoke-water produced with different sources (raw materials) and concentrations on seed germination and seedling vigor of tomato. Smoke-water was produced with ten different raw materials, for each was done a control (distilled water) and eight concentrations with smoke-water (1:5,000, 1:2,500, 1:1,000, 1:100, 1:50, 1:25, 1:10 e 1:2.5 v:v), making up nine treatments repeated eight times and distributed following a completely randomized design. Germination was assessed in the laboratory and the variables were evaluated five days after sowing. With the exception of one source, all tested raw materials showed, with the highest concentration tested (1:2.5), inhibitory effect on the germination of the tomato seeds. Promoting effect was observed mainly in smoke-waters produced from raw materials of palm leaves (Euterpe precatoria) and corn leaves (Zea mays), of light wood from a pioneer species (Cecropia palmata), sawdust of amazonian timber species (Dinizia excelsa; Sextonia sp.; Licania spp.; Aniba spp.) and of germination paper. The promoting effect was more significant on root length and on vigor index with concentrations between 1:25 and 1:5,000, in accordance with the source. The dilution of 1:25 excelled in most of the tested raw materials.