Seasonal variation of the foliar concentration of nutrients in fig orchards under intensive production systems

In order to investigate the fluctuation in the foliar concentration of nutrients during the growing season, a study was carried out in four fig orchards with intensive production systems, in the Comarca Lagunera, Durango, Mexico. A soil characterization was carried out, as well as monthly sampling and analysis, from April to October, of N, P, K, Ca, Mg, Fe, Cu, Mn, Zn and Ni. With respect to the foliar concentration of nutrients, in most cases they did not show significant differences between orchards, within each sampling date. The foliar concentration of N, Mg and Zn was highest at the beginning of the cycle (April-May) and then decreased during the cycle. On the other hand, the concentration of P, Ca, Cu and Ni showed a lower concentration at the beginning than at the end of the cycle, while K, Fe and Mn did not obtain a definite trend during the season. All the nutrients were within the levels of sufficiency reported in the literature, with the exception of Ca and Mg which were lower, despite which they did not show symptoms of deficiency. It was concluded that this species shows large seasonal variations during the cycle, in most of the nutrients; therefore, it is recommended that the sampling of leaves for nutrimental diagnostic purposes be made in June, in the period between the end of the harvest of brevas and before fruit harvest, which was when there was less variability among orchards.