Nutritional situation of pear orchards affected by late frosts

7 Pags.- 6 Tabls.- 1 Fig. The definitive version is available at: https://www.actahort.org/index.htmThis study was carried out in three 'Agua de Aranjuez' pear orchards located in the Alto Jalón area, which is regularly affected by late frosts. Twenty trees were identified in each plot. Individual leaf samples were taken during 5 consecutive years and tree yields were recorded. Based on the methodology for foliar diagnosis, the nutritional situation was defined in terms of N, P, K, Ca and Mg content and balance. The information obtained showed potasium and calcium deficits resulting in a clear nutriional imbalance in that area. The situation is worsened for trees wi th higher relati ve yields ( low yields in absolute terms), which may be due to the fact that the increased transfer of the deficient elements to the fruit results in a further reduction of leaf levels.The study was funded by CAICYT projects 2225/76 and 61142/02 and was conducted with the support of DGA (CONAI Project CA-11/86).Peer reviewe