Floral Induction of Longan (Dimocarpus longan) by Potassium Chlorate: Application, Mechanism, and Future Perspectives

Abstract

Longan (Dimocarpus longan L.) is one of the most important tropical and subtropical fruits in the world. Longan fruit has high nutritional and medical value, and is regarded as a treasure among fruits. Since it was first reported that potassium chlorate (KClO3) could be successfully applied to promote flowering in longan, this compound has been widely used in the production of on-season and off-season longan fruits. KClO3 has thus played a great role in promoting the development of the longan industry. In this review, we summarize the application methods, influencing factors, and physiological and molecular mechanisms associated with KClO3-mediated induction of longan flowering. It can be deduced that leaves may play a crucial role in the transport of and response to KClO3. Leaves supply carbon and nitrogen nutrition, and hormone and signaling molecules needed for the differentiation of apical buds. Moreover, cytokinins may be crucial for KClO3-mediated induction of longan flowering. More effort should be focused on studying the molecular mechanisms underlying this process. This will not only help us to better understand floral induction by KClO3 in longan but also enrich our understanding of flowering regulation mechanisms in woody plants.

Transcriptome sequencing and DEG analysis in different developmental stages of floral buds induced by potassium chlorate in <i>Dimocarpus longan</i>

“…These results align with those of previous studies, which showed that hormonal changes (e.g. involving auxin, cytokinins and gibberellin) are key factors in potassium chlorate-induced longan flowering (Hegele et al 2008;Huang et al 2021;Potchanasin et al 2009a;Qiang et al 2015;Susawaengsup et al 2011).…”

“…This trait is thought to depend on physiological processes that protect particular meristems from FI by floral promoting substances (Bangerth 2006;Wilkie et al 2008). For a few subtropical fruit tree species, it has become possible to induce flowering artificially by the application of chemicals, although the regulatory mechanisms behind this process may be rather different (Bonhomme et al 2000;Huang et al 2021;Li et al 2016). However, these techniques are still not fully developed and require further research and refinement.…”

Genome-Wide Identification and Expression Analysis of the R2R3-MYB Transcription Factor Family Revealed Their Potential Roles in the Flowering Process in Longan (Dimocarpus longan)

“…Environmental factors like low temperature, drought, and oxidative stress can regulate the flowering of many plants. Potassium chlorate (KClO 3 ) treatment is one of the most effective ways that widely apply in longan production to induce off-season flowering (Huang et al, 2021). To the best of our knowledge, KClO 3induced flowering has only been utilized in longan (Huang et al, 2021).…”

“…Potassium chlorate (KClO 3 ) treatment is one of the most effective ways that widely apply in longan production to induce off-season flowering (Huang et al, 2021). To the best of our knowledge, KClO 3induced flowering has only been utilized in longan (Huang et al, 2021). Studies on the physiological mechanism of KClO 3mediated FI showed that KClO 3 could increase the content of hormones such as cytokinin (CK) and salicylic acid (SA) in longan, which are closely related to plant flower formation (Sringarm et al, 2009).…”

Influence of warming climate and the green revolution on the optimum range of weather parameters of longan yield in Taiwan since 1909

“…In addition, Yen et al (2001) found that potassium chlorate could promote longan flowering. This method has been widely applied to longan fruit production (Huang et al 2021;Matsumoto et al 2007a), more widely in Northern Thailand (Sutigoolabud et al 2004(Sutigoolabud et al , 2005. However, the drawbacks of using potassium chlorate include the risk of combustion, lack of availability, and associated difficulties with transport and storage (Matsumoto et al 2007b).…”