Evaluación de sistemas de implantación y variedades de tuna (Opuntia ficus-indica)

The vegetative growth and productivity of four prickly pear varieties grown under two planting systems (single cladode and double cladode) was evaluated over a period of five years (1995-1999) in the San Juan province of Argentina. The three Argentine varieties examined (possibly ecotypes of the variety known locally as "yellow prickly pear without spines") came from the Santiago del Estero, Córdoba and San Juan provinces. The fourth variety used was "Gialla" from Italy. The double cladode plants reached a greater photosynthetic area and total cladode number than the single cladode plants. The double cladode system produced earlier fruits and the highest yields from the second year onwards. "Gialla" gave the highest fruit yields, and showed the greatest vegetative growth. No differences were observed between the Argentine varieties in terms of yield and plant growth. Planting double cladodes significantly improved fruit production and vegetative growth in the Gialla variety. Most of the fruit produced (80%) by the national varieties fell into the medium (96-140 g) and large (> 140 g) categories, while "Gialla" produced mostly medium and small sized fruits ( 80%) se concentró en las categorías mediana (96 a 140 g) y grande (> 140 g) en las variedades nacionales, y en las categorías mediana y chica (< 96 g) en "Gialla"