Factors affecting the presence of Typhlodromusspp. (Acarina: Phytoseiidae) in the calyx cavities of apple fruits and implications for integrated pest management
Predatory mites of the family Phytoseiidae include several species of importance as biological control agents of phytophagous mites in various crops including apples. We report on the post-harvest presence of the motiles of two species, Typhlodromus occidentalis and Typhlodromus pyri, in the calyx cavities of apple fruits of three cultivars. The mean numbers of motiles per fruit were as high as 6.10. The phytoseiid densities were lowest in cv. Bonza and tended to be greater in samples taken in late autumn, particularly in cv. Red Delicious. No significant effect (p > 0.05) was observed for different insecticide treatments. Phytoseiids remained present within fruits of cv. Granny Smith left on the orchard floor in winter. Together with an observed reduction in the numbers of T. occidentalis in the early spring, this suggests that fruits constitute an overwintering refuge. The findings are discussed in relation to the implications for biological control, in particular the minimization of the removal of natural enemies from orchards.
Photoperiodic Induction of Diapause in a Predaceous Mite, Metaseiulus occidentalis,
Adult females of Metaseiulus occidentalis (Nesbitt) (Acarina: Phytoseiidae) exhibited an imaginal, reproductive diapause when reared under 8 hours of light per day at 19°C. Diapause was concluded spontaneously when the females were maintained under these conditions. Total productivity was lower than normal when the females in diapause eventually oviposited.
The life-history of the eriophyid mite Aculus schlechtendali on apple in south-east England.
SUMMARY 
 
During 1975–77 the life-history of Aculus schlechtendali was studied in apple orchards. The morphology of the mite and its development at a range of temperatures were studied in the laboratory. 
 
 
 
Deutogynes of A. schlechtendali hibernated mainly in small permanently dormant buds and under loose bark on spurs and around buds on 1-yr shoots, and moved into fruit buds between the bud burst and pink but stages and into vegetative buds as the buds began to swell. Populations on leaves reached a peak in August and mite feeding at high density caused browning of the under surfaces. The return to hibernation sites began in July. 
 
 
 
The developmental stages of the mite are described. A generation took c. 39, 16 and 10 days at 10, 16 and 22 dC, respectively. Protogynes laid totals of 67–102 eggs at a rate of 1.7, 2.4 and 2.8 eggs/day at 10, 16 and 22 dC: deutogynes laid 21–47 eggs after hibernation at a rate of 1.3 and 1.6 eggs/day at 10 and 16 dC. The species was found only on cultivars and species in the genera Malus and Pyrus.