that if this leafhopper feeds on chokecherry first and then on peach, it \r±ll live 

 long enough to infeot the peach* However, if it feeds oa diseased peach first it 

 picks up a poison v;hich kills it before it can feed long enoxigh on another peach or 

 a chokecherry to transmit the virus* Since it has been found that the peach produces 

 enough hj'diicyanic acid at certain times of the year to kill other leafhoppers, this 

 explanation sounds plausible* 



— .JoS.Dalley 



4fr ^ ^<- -Ji- ■«■ ^- *•«■■«• ^ ■«■ it- * 



DR« GOHEEN TALKS TO STRAWBERRY GRCT'ifER S 



Dr» Austin Goheen, Plant Pathologist in charge of small fruit disease research 

 of the U» S» Agricultural Research Administration, talked to strawberry growers at 

 the twilight meeting at the University at Amherst on June ll;, and to another group 

 at the farm of Joseph reeling in North iuiddleboro on June l6» Dr, Goheen discussed 

 the three stravirberry diseases vfhich are giving the most trouble at the present timej, 

 red stele, virus and black root* 



Attempts have been made to control red stele by fvmigating the soil to kill 

 the fungus spores which can remain viable in the soil for several years and infect 

 any healthy plants which are set in such infected soil* Although some of the fumi-« 

 gants tried reduced very materially the number of spores in the soil, there were 

 still enouRh left to cause healthy plants to become diseased. The only hope for 

 control is still disease free plants set in disease free soil or the use of disease 

 resistant varieties in infected soil. He reported that Dr. D« H« Scott, the straw- 

 berry plant breeder, in the U, S, Agricultural Research Administration, has developed 

 selections resistant to three strains of red stele* One of these vdll be named and 

 introduced next winter* 



The ansiTer to the virus problem is to obtain virus-free plants ^ifhich are be- 

 coming available in rapidly increasing quantities*;'^ 



The cause of black root is still not knovm but the evidence that the ocadovr 

 nematode is a chief contributing factor, if not the causal organism, is increasing, 

 Dr* Goheen reported that he has been able to rid strawberry plants of nematodes by 

 giving them a heat treatment. Dipping the whole plant in hot water at 127 degrees 

 for two minutes does it* However, the plants must be dommt and be planted imaed- 

 iately after treatment or' the 3^ \rill be injured* Actually the nematodes, both root 

 knot and meadcrw neraatcdeo, can be killed in fifty seconds* The strav;berry plants 

 Tdll stand four or five minutes at that temperature. Consequently there is a safe 

 margin either i/ay, Dr, Goheen shovfed pictures of plants rid of nematodes in tMs 

 way, They were twice as large as untreated plants* 



This discover}' by I-'r, Goheen of a heat treatment for ridding strawberry plants 

 of nematodes is of tremendous importance* It opens the way to turning any virus-free 

 plants into both virus and nematode-free quickly and safely. It also makes it pos- 

 sible for anyone who has strawberries troubled vdth nematodes to treat their plants, 

 set them in fumigated soil, and have a little or no trouble from this pest* 



-/ Grovfers who wish to uee plants from their owi bed vdll do well to start ^dth 



virus-free plants and keep the spread of virus to a minimum by dusting with mala- 

 thion to control the aphids which carry the virus from diseased to healthy plants* 



, S.Bailey 



