-20- 



DISEASE DIAGNOSIS: INFORMATION FOR GROWERS 



Daniel R. Cooley , Christopher M. Becker 

 William J. Manning^ 



Department of Plant Pathology 



The Plant Pathology Department has a number of facilities in 

 the state devoted to plant disease diagnosis. The department at 

 Fernald Hall, the Shade Tree Laboratories, the Field Stations at 

 Waltham and Wareham, and specialists in different regions of the 

 state all offer assistance in identifying plant disease problems. 

 In addition, private consultants, usually working for agrichemical 

 companies, offer assistance. 



This system allows basically three options to fruit growers. 

 First, most problems are identified by growers themselves. V/hen 

 a problem is outside the realm of a grower's experience, a regional 

 specialist or chemical company representative can be consulted. 

 If the problem is not resolved at that level, a fruit grower or 

 the regional specialist will then go to the University. Hence, 

 generally it is the most difficult diagnosis problems which find 

 their way to the University. 



Sometimes these problems can be resolved in a matter of hours, 

 by examining the sample microscopically and consulting reference 

 books or other specialists. However, disease problems often take 

 longer to identify. Samples must be submitted for culturing and 

 then the organisms in these cultures have to be identified. This 

 may take weeks. Virus diseases are particularly difficult to ident- 

 ify, and may require months or even years to diagnose, as artificial 

 growth media which speed identification of other pathogens do not 

 \\fork for viruses . 



The policy at the University is to give growers an informed 

 opinion as soon as possible. If culturing tests or other information 

 contradicts the initial diagnosis, then the revised diagnosis is 

 relayed to the grower. The amount of effort involved in a diagnosis 

 will also reflect the options available in managing a problem. For 

 example, if the same fungicide plus pruning program are recommended 

 for managing several different canker diseases, it is not vital that 

 the specific canker problem be identified, as long as it is one which 

 can be managed by the program. To most growers, economical disease 

 control is the goal of diagnosis. The goal of the Plant Pathology 

 Department is to fit diagnosis to the growers needs. 



We encourage growers to consult with us on any problem. We would 

 appreciate suggestions as to how we might improve our diagnostic 



services 



1 



Extension Technician 

 2 



Extension Plant Pathologist 



