Smoke Induced Seed Germination in Maize in Response to Self and Other Plants Biomass-derived Smoke

Abstract

Fire ecology plays an important roles in germination and establishment of many plant taxa. Smoke inducedgermination and seedling vigor are well documented in many wild, crop, and weedy species. Karrikins(KAR) substances in smoke are reported to be responsible for these effects. However, only a few experimentshave been conducted on different plant-derived smoke effects on particular plant species’ seeds. This studywas conducted to investigate effects of self-derived and other plants biomass-derived smoke on germinationand post-germination processes in maize and its wild relative teosinte. Smoke derived from maize and alegume (Vigna unguiculata ssp. sesquipedalis) foliage burning was exposed to maize variety Guidan 162and teosinte (Zeamexicana (Schrad.) Kuntze). Germination percentage in both maize and teosinte exposedto maize smoke was found to be significantly higher than unexposed and legume smoke exposure, howevergermination in legume smoke exposure was found to slightly higher than control but not significantly so.Shoot length in maize seeds exposed to maize smoke was highest and differed significantly compared tocontrol and legume smoke exposure, while control and legume smoke exposure showed approximatelythe same shoot lengths. Coleoptile and primary root lengths showed nosignificant variation among alltreatments. Similarly, seminal root length didn’t show much variation but legume smoke exposure seedsfound to have the lowest seminal root length. Hence direct exposure to smoke without rinsing in watermay not positively affect the shoot and root length in maize. Further studies should address morphologicaltraits, transcriptome expression, and enzyme activity to clarify effects of self-derived and other plant-derived smoke on different plant species.