ABSTRACT


Gonzalo Gil S.1, José Rodríguez S.2, Sergio González M.3, Domingo Suárez F.4, Horacio Urzúa S.5
 
The seasonal trends of N, P, K, Ca, Mg, Mn, Cu and Zn in the lamina and petiole of leaves opposite to clusters in grape (Vinis vinifera L.) cv. Semillon were established. The foliar samples were collected at a vineyard located near Santiago, Chile. The total nitrogen concentration in the lamina was highest in the sample collected prior to bloom. The level decreased within 20 days, and a second decrease ocurred between 110 days after bloom and fruit maturity. The nitrate nitrogen in the petiole followed a similar trend, except that the concentration between berry set and veraison was more stable. The P content decreased rapidly during the pre and post bloom period in both tissues; after berry set, the concentration decreased slowly in the blade, but remained nearly constant in the petiole.The Ca concentration in both tissues and Mg and Mn in the petioles showed increasing trends. The Mg and Mn levels in the lamina showed no definite pattern. Likewise, Potassium level in the blade showed no trend but that in the petiole. had a decreasing trend over the season with great fluctuations. The trends of Cu in the leaf blade showed small fluctuations in relation to the seasonal mean but that of the petiole was nearly constant during the entire season. Zn in the lamina showed a sharp initial decrease at bloom period but thereafter remained fairly constant whereas Zn in the petioles remained fairly constant over the entire samplig period. Analysis of petiole opposite to clusters at bloom period was considered to offer a reliable criteria for diagnosing the status of the above named elements at a time.
Keywords:
1Ing. Agr., Ph. D., Profesor del Departamento de Frutales y Viñas, Escuela de Agronomía, Universidad Católica de Chile. Casilla 114-D, Santiago, Chile.
2Ing. Agr., M. S., Profesor del Departamento de Edafología, Escuela de Agronomía, Universidad Católica de Chile. Casilla 114-D, Santiago, Chile.
3Ing. Agr., M. S., Depto. de Agrología, Servicio Agrícola y Ganadero. Avda. Sucre 2397, Santiago, Chile.
4Ing. Agr., M. S., Profesor del Departamento de Edafología, Escuela de Agronomía, Universidad Católica de Chile. Casilla 114-D, Santiago, Chil