Stimulatory effects of smoke and smoke-derived butenolide on crop plants

Abstract

Plant-derived smoke is a powerful germination cue that promotes the germination of many species from fire-prone and non-fire areas [1]. A butenolide-type compound, 3-methyl-2H-furo[2,3-c]pyran-2-one, isolated from plant-derived smoke, was found to be the highly active germination cue present in smoke [2]. It promotes germination at concentrations as low as 10-9 M, and also promotes seedling vigour of several crop plants such as tomato, bean, okra and maize [3]. Preliminary toxicity testing has shown that the compound is not mutagenic or genotoxic at the concentrations tested (1×10-4 M and lower) [4]. Treatment of tomato (Solanum lycopersicum cv. Heinz-1370) seedlings with smoke-water and 1×10-9 M butenolide was conducted under greenhouse conditions. Smoke-water treatment resulted in maximum height, number of leaves and stem thickness from 57 to 78 days after sowing. For both smoke-water and butenolide-treated plants, the percentage of plants with fruit was higher than the control. In addition, smoke-water treatment significantly (P<0.05) increased the total number of marketable fruit. The butenolide-treated plants also yielded more fruit (although not significant). Thus, smoke technology and the smoke-derived butenolide hold promise for use in agriculture and horticulture for improving seed germination, seedling vigour and potentially increasing overall yield.