Table 1 . Average ovipositional preference rank among apple cultivars according to seasonal 

 period.* 



Values within a column followed by the same letter are not significantly different at odds of 

 19:1. Certain circumstances disqualified results of late-season tests for statistical analysis. 



Mac and Akane), along with mid-ripening cultivars 

 (Mcintosh, Gala, and Cortland to a lesser degree) and 

 a late ripening cultivar (Braebum) became acceptable 

 for oviposition during mid season. During late season, 

 all three mid-ripening cultivars (Mcintosh, Gala, and 

 Cortland) were the most acceptable for oviposition. 

 Acceptance of late-ripening cultivars was moderately 

 high in 1999, but remained low in 2000 despite the 

 fact that apples of those cultivars had become sweet. 

 Interestingly, AMF cultivar preferences in terms 

 of accumulation on traps in our field study and 

 ovipositional acceptance here were not always in 

 accord. Some cultivars were both highly attractive (or 

 highly arrestive) as well as highly acceptable for 

 oviposition (Akane, Gala, Jersey Mac, and Tidemann 

 Red) and therefore should be considered as highly 

 susceptible to AMF damage. Other cultivars 

 accumulated large or substantial numbers of AMF but 

 bore fruit comparatively unacceptable to ovipositioning 

 females (Fuji, Golden Delicious, and Delicious), or 

 failed to accumulate large numbers of AMF despite 

 the fact that they bore highly or substantially acceptable 

 fruit (Mcintosh, Cortland, and Braeburn). Such 



cultivars can be considered as being moderately 

 susceptible to AMF damage. Finally, cultivars that 

 were both comparatively unattractive and 

 comparatively unacceptable should be considered as 

 tolerant or of low susceptibility to AMF (e.g., Paula 

 Red). 



Conclusions 



Combined findings of an earlier study on the 

 influence of tree size and planting density on AMF (Fall 

 1999 issue of Fruit Notes), the preceding study on 

 cultivar susceptibility to accumulation of AMF, and 

 this study on cultivar susceptibility to AMF oviposition 

 suggest that orchard architecture could have a strong 

 impact on the success of behavioral control of AMF 

 with traps. 



For example, an idea! type of orchard architecture 

 to achieve maximum AMF control using odor-baited 

 spheres placed on perimeter-row apple trees (to 

 intercept immigrating AMF) might be as follows: plant 

 trees on dwarfing rootstock (M.9 or M.26) and arrange 

 cultivars in such a way that late-ripening cultivars such 



Fruit Notes, Volume 66, 2001 



23 



