Plant derived smoke stimulation for seed germination and enhancement of crop growth: A review

Abstract

Smoke is an important factor involved in fire and post fire germination cues. The role of smoke in stimulating germination was first highlighted in South Africa in a study on Audouinia capitata, a threatened fynbos species. Farmers throughout the world have traditionally used fire and smoke in grain drying practices. It is thought that these methods improve germination and seedling vigor. Smoke has been applied in agriculture mainly by two ways viz., Aerosol method and Smoke water method. In aerosol method, seeds were directly exposed to smoke generated from burning plant material. Smoke-water is one of the most convenient means of application. The biologically active compounds present in smoke readily dissolve in water and when this smoke-extract is used as a diluted solution, treated seeds of many species show a marked improvement in germination. The main active germination compound of smoke-water derived from burned plant materials and cellulose has been identified as butenolide [3-methyl-2H-furo (2, 3-c) pyran-2-one], which is effective at very low concentrations (1 ppb). The compound has recently been referred to as "karrikinolide". Following the initial isolation of KAR1, a whole new family of plant growth regulators, termed 'karrikins', were identified in smoke and several related compounds have been synthesized. It is estimated that between 2 and 5 g of KAR1 is more than sufficient for 1 ha of land application rates that are commercially viable. Application of smoke in various agricultural, horticultural forage and forestry crops had found that smoke acted as a cue for breaking seeds of dormancy, improve seed germination, seedling growth, flowering, plant biomass of different plant families, Invitro plantlet regeneration and pathogen control (Anti-microbial properties).

Using smoke solutions in grass pea (Lathyrus sativus L.) to improve germination and seedling growth and reduce toxic compound ODAP

“…The positive and stimulating effects of smoke solutions on germination and plant development were also demonstrated in many previous studies (Ghebrehiwot et al, 2012;Kamran et al, 2013;Govindaraj et al, 2016).…”

“…More recently, the positive effects of smoke and smoke product-derived plant materials on germination and plant growth have been reported (Govindaraj et al, 2016). It was reported that smoke components encouraged germination (De Lange and Boucher, 1990) and played an important role in the breakdown of dormancy (Light et al, 2002(Light et al, , 2004Van Staden et al, 2004;Ghebrehiwot et al, 2011).…”

Can plant derived smoke solutions support the plant growth and forage quality in the hydroponic system?

“…All these results showed that there were positive and stimulating effects of priming with oat and grass pea derived smoke solutions on growth and forage quality of hydroponic barley and wheat. Previous studies showed that plant derived smoke solutions have stimulating effect on the germination and seedling growth of Poacea families (Ghebrehiwot et al 2012), lettuce (Kamran et al 2013) and a threatened fynbos species (Govindaraj et al 2016). However, the effectiveness of smoke solution in hydroponic system was first mentioned in this study.…”

Molecular functions of nitric oxide and its potential applications in horticultural crops

“…In tomato seeds, NO scavengers maintained seed dormancy and counteracted the stimulating effect of fluridone 98 . It is well known that smoke is commonly used in horticulture to break dormancy and promote seed germination of some vegetables, such as lettuce and celery 99 . It is now clear that NO is among the essential active compounds responsible for seed germination stimulated by smoke.…”