Karrikins (KARs) have been identified as molecules derived from plant material smoke, which have the capacity to enhance seed germination for a wide range of plant species. However, KARs were observed to not only impact seed germination but also observed to influence several biological processes. The plants defected in the KARs signaling pathway were observed to grow differently with several morphological changes. The observation of KARs as a growth regulator in plants leads to the search for an endogenous KAR-like molecule. Due to its simple genomic structure, Arabidopsis (Arabidopsis thaliana L.) helps to understand the signaling mechanism of KARs and phenotypic responses caused by them. However, different species have a different phenotypic response to KARs treatment. Therefore, in the current work, updated information about the KARs effect is presented. Results of research on agricultural and horticultural crops are summarized and compared with the findings of Arabidopsis studies. In this article, we suggested that KARs may be more important in coping with modern problems than one could imagine.

Department of Botany and Plant Physiology Faculty of Agrobiology Food and Natural Resources Czech University of Life Sciences 16500 Prague Czech Republic

Department of Plant Biology Educational and Scientific Center Institute of Biology and Medicine Kiev National University of Taras Shevchenko Volodymyrska 64 01033 Kyiv Ukraine

Department of Plant Physiology Faculty of Agrobiology and Food Resources Slovak University of Agriculture 94976 Nitra Slovakia

Laboratory of Bioclimatology Department of Ecology and Environment Protection Poznan University of Life Sciences Piątkowska 94 60 649 Poznań Poland

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