Preliminary Study Mechanism of Ethylene Induced Abscission Zone Formation and Function of GhArfGAP in Upland Cotton Boll Stalk

Abstract Background: With the continuous growth of population, the demand for fiber is also rising sharply. As one of the main fiber plants in the world, cotton fiber yield of upland cotton is affected by boll abscission, which is related to the formation of abscission zone. Therefore, we explored the formation of the abscission zone of upland cotton.Result: The formation of abscission layer of cotton boll stalk was promoted by exogenous ethylene. It was found that both the number of Golgi apparatus and the number of stacking layers increased in the dissociated cells. The GhArfGAP gene family in upland cotton was screened by bioinformatics method, and the species and evolutionary relationship of GhArfGAP gene family were analyzed. qRT-PCR showed that the expression patterns of GhArfGAP13,GhArfGAP15, GhArfGAP25 and GhArfGAP34 in cotton were spatiotemporal specific. Subcellular localization suggested that GhArfGAP25 played a role in Golgi apparatus . The expression of GhArfGAP25 in transgenic Arabidopsis increased in the root, stem and leaf.Conclusions: Ethylene could induce the formation of abscission zone in upland cotton. GhArfGAP13,GhArfGAP15,GhArfGAP25,GhArfGAP34 might regulate the changes of Golgi apparatus in abscisson zone.Taken together the findings provide new ideas for the study of cotton abscission formation.