H. glycines J 6 



degree of confidence in the possibility of resistance occurring in the 

 test plant. If both plants were free of cysts, the results on that 

 test plant were disregarded. Lines which showed signs of resistance 

 are, of course, being tested ajrain this season. 



Dr. Ross is currently checking the roots of some of the resistant lines 

 to determine if the larvae have entered. He is finding that the larvae 

 do enter, but fail to develope. This is about as far as the work has 

 gone, to date, along the line of resistance as a means of control. It 

 does appear that in the soybean germ plasm there certainly is some re- 

 sistant genetical material for the plant breeders to work with. 



Now, regarding the distribution of the soybean cyst nematode. It appar- 

 ently is confined to a small area within North Carolina, but, as you 

 know, it has been reported now from at least five other states. Perhaps 

 one reason it showed up as it did in North Carolina was because of the 

 intensive soybean cultivation in the particular area for about 15 to 20 

 years. Every summer the fanners grew soybeans as a cover crop. It 

 seems that the histoiy is similar in the infested areas in Tennessee, 

 that is, soybeans were grown continuously over a long period of years. 

 I do not know that we can say the pest was introduced from the Orient, 

 although it could have been. Certainly we have no proof. I believe it 

 is going to show up in this country wherever, as Ilr. Al Taylor has 

 pointed out, we have grown soybeans or some other susceptible crop for 

 a good many years. 



In concluding, I would like to give you the little bit of information 

 we do have on the longevity of the nematode in the soil. This past 

 January I collected soil fron the field where the nematode was origi- 

 nally found in North Carolina. Cysts screened from this soil, which 

 had not been replanted to soybeans since 19Sh, yielded viable larvae. 

 There had been two complete years with non-host crops in the field. I 

 cannot, at the present, give you the degree to which the population has 

 been reduced. 



I would like to call on Dr. Andes of Tennessee for information of the 

 soybean cyst situation and work begun in his state. 



J. 0. Andes 



In September of 1956 we were processing soil from Lake County, which 

 is in the northwest corner of Tennessee, and we found cysts in some of 

 the samples. We sent them to Dr. Sasser for checking and later to '■ r. 

 Taylor at the Section of Nematology. They were identified as being the 

 soybean cyst nematode. Following this discovery of the pest in our 

 state, the Plant Pest Control workers came to begin a survey. The dis- 

 tribution of the nematode extended into various areas in several of 

 the counties in the western end of the state. A mof^ting was called in 

 Memphis to have a hearinr^ on the situation. One result has been the 

 establishmc-nt of a quai-antine which went into force yest'=rday. I have 



