STRAWBERRY CULTIVARS GROWN UNDER PROTECTED STRUCTURE AND THEIR SUSCEPTIBILITY TO NATURAL INFESTATION OF THE COTTON APHID, APHIS GOSSYPII AND TO POWDERY MILDEW, SPHAEROTHECA MACULARI F. SP. FRAGARIE

Strawberry (Fragaria ananassa Duchesne) cultivars were evaluated to determine their susceptibility to a natural infestation of the cotton aphid, Aphis gossypii Glover (Homoptera: Aphididae), and powdery mildew, Sphaerotheca macularis f. sp. fragarie, in a passively ventilated greenhouse.
Cultivars were planted at a density of 22 plants per m2. No insecticide and only one fungicide application was made.
Bi-weekly releases of Aphidius colemani L. at an approximate rate of 10 wasps per m² were made to control aphids.
Ten strawberry leaflets were selected at random, and the total number of aphids and parasitized aphids per leaflet were counted weekly.
The presence of powdery mildew also was recorded. ‘Sweet Charlie’ and ‘Carmine’ sustained the greatest average number of aphids per leaflet throughout the growing season, while FL 97-39 and ‘Camarosa’ had the lowest number.
Populations of the aphid continued to rise in all cultivars from late November to mid January; however, 95% control by A. colemani was achieved by the end of February.
FL 97-39 produced the most fruit and possessed the lowest number of aphids per leaflet throughout the season; however FL 97-39 was the most susceptible to powdery mildew.

VII International Symposium on Protected Cultivation in Mild Winter Climates: Production, Pest Management and Global Competition

S.I. Rondon, A.V. Paranjpe, D.J. Cantliffe, J.F. Price

Biological control, greenhouse, pests

https://doi.org/10.17660/ActaHortic.2004.659.47