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The program included talks, demonstrations and field trips. Although niany 

 topics were discussed, most attention was given to breeding, virus and the nematode 

 problem. 



The use of virus-free plants has increased very materially this year 

 as more virus-free plants were made available. The progressive nurseries are making 

 every effort to increase the supply and keep them virus-free. Two methods are being 

 used to keep the "foundation stock" or "mother plant beds" free of virus. In some 

 states, as is being done in liassachusetts, the plant growers are building screenhouses 

 to protect the foundation stock plants from the aphids which carry the virus from 

 plant to plant. In others, the foundation stock is grown in Isolated areas where 

 there are neither cultivated nor wild strawberries for several miles, as is being 

 done in California and Tennessee, 



One of the serious problems being faced by every state where strawberries 

 are grown is how to be sure that the g rovrer gets virus-free plants when he orders 

 them. This involves a number of technical, inspection, control and financial problems. 

 These are being attacked in several ways by different states, Tennessee has decided 

 to follow a "get tough" policy, A rather detailed set of rules and regulations has 

 been established and will be rigidly enforced xintil relaxation seems justified. The 

 cost of "indexing" (testir^ for virus), inspection and certification is borne by the 

 State, California, which also has a stringent set of rules and regulations, charges 

 the plant grower for these services. In both states the plant grower is allowed to 

 charge a premium of $U»00 per thousand for the virus-free plants. 



Other states are approaching the problem the other way around. That is, they are 

 starting out with a few milri regulations which will be tightened upas it appears 

 necessary. Other states, including mssachusetts, have set up no regvilations as yet. 



The nematode problem received a great deal of attentiontecause it is one of 

 the neT,Test fields of strawberry research and also because Dr, Caroline Klinkenberg of 

 the Netherlands was present and discussed the results of her work. She stated that 

 the nematode problem is the most serious strawberry problem in the Netherlands and 

 that work on it was started during the last war. It has still not been proved that 

 nematodes are the cause of the root condition called black-root rot, or simply black 

 root, , However, it has been shown quite conclusively that where black root is a pro- 

 blem, plant growth has been greatly improved and yields increased by soil fximigation 

 vdth nematocides, Dr, Braun, of the Geneva New York Experiment Station, discussed 

 his work on this same problem and agreed with Dr, Klinkerberg's conclusions. 



During the discussion it was emphasized that the soil must be in the 

 right condition for fumigation, that is, in condition to make a good seed bed, the 

 right amount of soil fumigant must be used, it must be put down deep enovigh, at least 

 six inches, the soil must be sufficiently warm, 50^, for the commonly used fumlgants, 

 and the fumigant sealed in by a drag, smoothing harrow or cultipacker. Therefore, 

 for strawberries, fumigation in the fall before the plants are set is a practical 

 necessity. 



Strawberry breeding is being carried on in twenty-one colleges and research 

 stations. The objectives vary with the needs of a particular region, Ona of the ob- 

 jectives of the breeding work at Beltsville is the production of varieties resistant 

 to all three strains of the jred stele disease. This phase of the breeding work is 

 being carried on in cooperation with the University of Maryland, The variety Stele- 

 master, which was named and introduced last vd-nter, is one of the products of this 

 project. It is recognized by the men who named and introduced it that Stelemaster 

 is only a stop-gap variety to be grown where it is impossible to grow other varieties 

 because of red stele. Varieties which are superior to Stelemaster and have the same 

 multiple resistance to red stele are in prospect for the very near future. 



