Abscisic acid alleviates iron deficiency by regulating iron distribution in roots and shoots of apple

Abstract Hormone regulation is a crucial factor during plant growth and development, and is widely involved in various stress responses of plants, including the iron (Fe) deficiency response. Apple faces a broad Fe deficiency as a major fruit in China, due to improper cultivation management. In this study, we explored the feasibility of using abscisic acid (ABA) to alleviate Fe deficiency in apple. ABA treatment increased total Fe content in shoots, but no significant change in roots under a Fe deficient condition. Interestingly, exogenous ABA not only significantly alleviated chlorosis in new leaves but also promoted development of the root system under the Fe deficient condition. Taken together, our data demonstrate that exogenous ABA alleviates Fe deficiency by promoting root development and regulates the Fe distribution in the roots and shoots of apple.