RT article T1 Effects of the Frequency of Iron Chelate Supply by Fertigation on Iron Chlorosis in Citrus A1 Banuls, Josefina A1 Quinones, Ana A1 Martin, Bernardo A1 Primo-Millo, Eduardo A1 Legaz, Francisco K1 Fruit quality K1 Iron deficiency K1 Iron chelate K1 F61 Plant physiology - Nutrition K1 Citrus K1 Fertigation K1 Mineral nutrients AB A field experiment was carried out in a drip‐irrigated orchard of Clementine (Citrus clementina Ort. ex. Tan) grafted on Troyer citrange (C. sinensis × Poncirus trifoliata) rootstock located in the Valencian Citrus area (Spain). The trees received a single iron (Fe) EDDHA (ethylene diamine diorthohydroxyphenyl acetate) rate (3 g Fe tree−1) supplied in different application frequencies from April to September (8‐, 4‐, 2‐, or 1‐week intervals). Leaf chlorophyll (Chl) concentrations were estimated every month by using an SPAD‐502 meter. The foliar contents of Fe were also evaluated with time. Mineral composition of leaves, total Chl concentration, yield, and fruit quality were also evaluated at the end of the assay. SPAD readings, Chl, N, K, Mg, Fe, and Mn concentration in leaves increased as a result of Fe application. The concentration of Zn, however, significantly decreased in comparison to the control trees. Iron treatment increased yield and some of the fruit quality parameters, like total juice, sugar, and acid contents. Iron application frequency had not a consistent effect on the concentrations of macro and micronutrients in leaves, yield, and fruit quality. The highest values of SPAD readings and the leaf Chl content were obtained when Fe was applied at 4‐week intervals along the year. These results suggest that soil Fe‐EDDHA application with a moderate frequency could be recommended to the Citrus farmers in the area for a more rational Fe application along the growth cycle in Citrus orchards. PB Taylor & Francis SN 0190-4167 YR 2003 FD 2003 LK http://hdl.handle.net/20.500.11939/6578 UL http://hdl.handle.net/20.500.11939/6578 LA en NO Bañuls, J., Quiñones, A., Martín, B., Primo‐Millo, E., & Legaz, F. (2003). Effects of the frequency of iron chelate supply by fertigation on iron chlorosis in citrus. Journal of plant nutrition, 26(10-11), 1985-1996. DS MINDS@UW RD Aug 16, 2022