Life Without Alar 



Wesley R. Autio 



Department of Plant & Soil Sciences, University of Massachusetts 



In August, 1985 the controversy began regarding 

 the safety of Alar^*^ residues on apples. Since that time 

 many discussions and arguments have occurred. A 

 recent "60 Minutes" program fueled the controversy 

 by presenting claims made by the Natural Resources 

 Defense Council that Alar is a potent carcinogen. The 

 scientific data available certainly do not support that 

 view; however, the widespread publicity likely will 

 eliminate Alar-use as a hoilicultural practice. Apple 

 growers must look toward a future without Alar. In 

 this aiticle I shall present some of the ways that may 

 help reduce the need for Alar. 



Before discussing specific activities, we must be 

 clear on what benefits are received from Alar. The first 

 and foremost function of Alar is to act as a "stop-drop." 

 This function allows a grower to harvest most of his 

 crop before it drops to the ground. By allowing fruit to 

 remain on the tree longer they are able to color more 

 fully, giving higher grade fruit. One reason why fruit 

 stay on the tree longer is that Alar delays the beginning 

 of fruit ripening, which results in less-ripe fruit for 

 storage, which then allows the fruit to retain high 

 quality for a longer time. In particular, the apples stay 

 firm for a longer period of time. 



Alternative approaches to the use of Alar must 

 address these benefits that Alar provides. Approaches 

 will be divided into two types: short-term practices and 

 long-term changes. Short-term practices include sev- 

 eral activities, but in general these are practices which 

 may be undeilaken this season to reduce the losses 

 associated with the non-use of Alar. Long-term 

 changes require more time and capital to implement. It 

 must be understood that Alar provided a gi'eat deal of 

 benefit, and no practices are real alternatives: they only 

 assist in reducing the losses associated with non-use of 

 Alar. 



Short-Term Practices 



Pruning 



Several Fruit Notes articles [52(3):7-8; 53(1):12- 

 13; 53(2): 1; and 53(3): 1-2] have discussed the effects of 

 pruning, particularly summer pruning, on the produc- 

 tion of high quality fruit. Removal of upright, hanging, 

 and shade-causing wood in the summer can result in a 



dramatic increase in light penetration, fruit coloration, 

 and packout. Additionally, it causes earlier coloration 

 and thus allows earlier harvest, hopefully reducing 

 some of the need for Alar while not reducing average 

 fruit quality. Dormant pruning also is important, 

 specifically in improving light penetration to the fruit. 

 For more specific information about summer pruning 

 practices, see Fruit Notes 53(2):1, and for more infor- 

 mation about dormant pruning to improve packout, 

 see Fruit Notes 53(1):12-13. 



Chemical Treatments 



There are no chemical alternatives to Alar. How- 

 ever, there are two chemicals that can be used to 

 expand the harvest season: Ethrel and NAA. The 

 problem with both chemicals is that they may render 

 the fruit unusable for long-term storage by advancing 

 ripening. Ethrel is used to advance the hai^vest season 

 by breaking down to ethylene and triggering ripening. 

 Treatment with Ethrel results in marketable fruit 

 early in the season, but also fruit that probably must be 

 consumed immediately, because they are too ripe to 

 store. NAA is a "stop drop." It will significantly delay 

 premature fruit drop, but it also advances fruit ripen- 

 ing. NAA can expand the season, but treated fruit 

 must be sold relatively quickly. Details on the use of 

 both of these chemicals are given in the New England 

 Apple Spray Guide. 



Harvest and Storage Management 



Without Alar the fruit in storage probably will be 

 riper than what growers are used to. To maintain fruit 

 quality throughout the storage period, the fruit must 

 be handled with greater attention to details than if they 

 had been treated with Alar. This additional care in- 

 cludes more accurate attention to cooling and to the 

 rapid establishment and maintenance of optimal tem- 

 perature and atmosphere conditions, as well as to 

 application of the appropriate postharvest chemical 

 treatments. No longer will sloppy storage manage- 

 ment be acceptable, since the fruit will show the quality 

 of storage management more readily than before. In 

 addition to storage management, the intensity of har- 

 vest management must be increased. Growers must 

 accurately manage their harvest so that the most ap- 



FruU Notes, Spring, 1989 



