Incidence of misshapen fruits in strawberry plants grown under tunnels is affected by cultivar, planting date, pollination, and low temperatures

Abstract

Misshapen fruit represent a significant problem for strawberry (Fragaria 3ananassa Duch.) producers around the world. We investigated the effect of cultivar and different cropping practices on the productivity of strawberry plants growing in tunnels at Huelva (Spain) over three years. In the first experiment, 'Camarosa', 'Ventana', and 'Medina' were planted on 10 or 22 Oct. at standard (30 × 25 cm), wide (35 × 25 cm), or narrow (25 × 25 cm) spacings. In the second experiment, 'Camarosa' was grown in macro- or microtunnels with and without bees. There was no effect of plant density. Planting time resulted in higher early yields in 'Ventana' and higher misshapen fruit in 'Camarosa' with an early compared with a late planting. 'Camarosa' had the lowest yields and the highest incidence of misshapen fruit. More of the early crop was misshaped and this was related to low temperatures in the 7 weeks before harvest. Pollination reduced the incidence of misshapen fruit and increased yield. Plants grown in macrotunnels were only more productive than those grown in microtunnels when they were pollinated by bees. These results demonstrate that the productivity of strawberry plants growing in tunnels can be enhanced by the selection of the appropriate cultivar, planting date, tunnel system, and pollination protocol. The use of macrotunnels with supplementary pollination results in better economic returns by increasing yield and decreasing the incidence of misshapen fruit. In addition, in some cultivars this profit can be enhanced by early planting, which enables early arrival of fruits into the markets at better prices for growers.