For Arabidopsis, many studies have shown that RAP2 is involved in oxygen sensing, which plays a key role in controlling root bending in response to hypoxia (Hartman et al., 2019; Smit et al., 2020; Tang et al., 2021; Seok et al., 2022); bHLH029, as a putative transcription factor encoding the regulation of iron uptake responses, mRNA was detected in the outer cell layer of roots and accumulated in iron deficiency, similar to FER in tomato, as a regulator of iron uptake (Cai et al., 2021; Kanwar et al., 2021; Song et al., 2022). The gene discussed is FER; the disease is Iron deficiency anemia.