FIELD OBSERVATIONS ON OVIPOSITION OF CODLING MOTH, CYDIA-POMONELLA (LINNAEUS) (LEPIDOPTERA, OLETHREUTIDAE), IN AN UNSPRAYED APPLE ORCHARD IN SOUTH-AFRICA
Tl. Blomefield et al., FIELD OBSERVATIONS ON OVIPOSITION OF CODLING MOTH, CYDIA-POMONELLA (LINNAEUS) (LEPIDOPTERA, OLETHREUTIDAE), IN AN UNSPRAYED APPLE ORCHARD IN SOUTH-AFRICA, African entomology, 5(2), 1997, pp. 319-336
Oviposition of the codling moth, Cydia pomonella (Linnaeus), was studi
ed from 1985 to 1989 in unsprayed apple orchards on the Elgin Experime
nt Farm, Grabouw, Western Cape Province. There was a significant diffe
rence in the site of oviposition, more eggs being recorded from the bo
ttom half of the western and southern aspects of the tree. There was a
lso contingency between the time of year and level (upper half, lower
half) in the tree. Moths of the first generation preferred the bottom
half of the tree and second and third generation moths the top half of
the tree. The preferred oviposition sites on Granny Smith (GS) and Go
lden Delicious (GD) cultivars, in order of preference, were leaves, fr
uit and wood. More eggs were laid on the fruit of GS spurs (35.6 %) th
an on those of GD spurs (10.7 %). On fruit spurs, there was a signific
ant increase in the number of eggs on GD leaves, and GS fruit over the
season, whereas the number of eggs on GS leaves and GD fruit remained
constant. On branches, there was an increase in the number of eggs on
GD and GS leaves, but not on the fruit or wood. The distribution with
in different fruit-bearing classes (1-4 fruit per spur) was random onl
y for one fruit per spur) while on the other spur classes clustering o
ccurred.