| Sumario: | [EN] Current agriculture, increasingly subject to environmental restrictions and reduced economic margin, calls for a greater rationalization of the cultivation methods used. These factor have a special interest in the crop of loquat because this crop have not rational criteria of fertilization that enable the realization of adjusted contributions of nutrients for optimal production and quality of the fruit. This production must be economical and environmentally sustainable. The aim of this work is to establish a protocol of nutritional diagnosis in the crop of Japanese loquat (type of leaf, time of sampling and foliar concentration of macro and micronutrient reference levels). This protocol allow for diagnose the nutritive state of the plant. On the other hand, this study delves into the knowledge of the dynamics of nitrogen, using isotope dilution technique (15N), which allows to adjust the contribution of nitrogen fertilizers to the needs of the crop. The studies for the establishment of nutritional diagnosis were held in forty plots of reference, with optimal production and quality of the fruit in adult plants of loquat grafted with the Algerie variety on ungrafted. The nitrogen dynamics tests were performed in the experimental plot of the Cooperativa Ruchey in Callosa d'En Sarrià (Alicante, Spain) with plant of the same variety in production. The results obtained have established a nutritional diagnosis protocol for Japanese loquat. For foliar sampling is set as reference, the third leaf from the base of the budding of spring (139 state scale phenological BBCH, first fully expanded leaves). These leaves were sampled in August and September. Also, the foliar benchmark indices were obtained for N, P, K, Ca, Mg, S, Fe, Zn, Mn, Cu, B and Na, which diagnosing the nutritional status of the plant as deficient, low, optimum, high or over in Japanese loquat. This parameter establishes rational criteria of fertilization. The fertilizer brought before sprouting of spring is font of nitrogen for the summer leaves and skeleton panicle. The fertilizer brought before summer sprouting and later of the blooming is who primarily contribute to the development of the fruit and its maturation. The foliar application of urea is a tool to supplement the foliar concentration of the nitrogen in leaves and fruits. For this motive, the planning is very important. The most suitable time for applying foliar urea are at beginning or the sprouting of summer and the studded fruit. Finally, the relative contribution from nitrogen is decisive for the development of the news organs. Therefore, it would be of interest to consider reducing fertilizer early contributions, provide that the nutritional status of the plant is adequate to sustain, higher, the development of these.
|
|---|
