Nutritional status, vigor and yield of grapevines intercropped with cover crops/Estado nutricional, vigor e producao em videiras cultivadas com plantas de cobertura

Perennial or annual species of cover crops can be grown in vineyards to protect the soil surface and to reduce the availability of water and nutrients to the vine. The study aimed to evaluate the nutritional status, vigour and yield of grapevines intercropped with some species of cover crops under two different managements. A field experiment was conducted for two years, 2009 through 2011, in a vineyard of cv Cabernet Sauvignon in a Haplumbrept soil. The following treatments were evaluated: a control, where weeds were controlled by chemical drying in the grapevine row and by mowing in the inter row; a perennial species, tall fescue (Festuca arundinacea); two sequences of annual species, ryegrass-moha (Lolium multiflorum-Setaria italica) and oat-buckwheat (Avena sativa-Fagopyrum esculentum); and two types of crop residues management, with and without its transfer of the grapevine row to the inter row. The grapevine leaves were sampled at flowering and at berries softening stages for analysis of N, P, K, Ca and Mg contents. It was determined the branches and internodes lengths, branches pruned mass, grape bunches length, width and mass, yield per plant and the weight of 100 berries and it was also calculated the Ravaz index of the grapevines. Grapevines intercropped with succession of annual cover crops showed higher total N content in leaves at flowering, vigour and grape yield. The transfer of the crop residue from the row to the inter row, did not affect the grapevine vigour and yield, but decreased the total content of N in the leaves at flowering. The tall fescue as soil cover crop in vineyard can be an effective alternative to reduce the vigor of the grapevine. Index terms: Green manure, mineral nutrition, green cover, yield components, Vitis vinifera. Especies perenes ou anuais de plantas de cobertura podem ser cultivadas em vinhedos para proteger a superficie do solo e tambem controlar a disponibilidade de agua e nutrientes a videira. O trabalho objetivou avaliar o estado nutricional, o vigor e a producao de uva em videiras consorciadas com especies anuais e perenes de plantas de cobertura submetidas a dois manejos. O experimento foi conduzido nas safras de 2009/2010 e 2010/2011, em vinhedo da cultivar Cabernet Sauvignon, em Sao Joaquim (SC), sobre um Cambissolo Humico Distrofico. Os tratamentos foram: testemunha, caracterizado pela presenca de plantas espontaneas controladas por dessecacao na linha e por rocadas nas entrelinhas; a especie perene de