H. glycinessS 



debris of various sorts in baggage, biirlap bags, and things of that 

 natiore. In this particular area of North Carolina, soybeans are 

 grown rather incidentally during the suimier months as a soil-builder 

 and also to provide some shading for gladiolus bulbs. We were inter- 

 ested in whether or not a period of storage after digging the bulbs 

 has any material effect on killing the nematodes, or whether they 

 could remain viable in a dry condition, like H. rostochiensis and some 

 of the others, for an extended period of time. 



^/\fhile this work is by no means complete. Dr. Skotland did get convincing 

 evidence that desication has a very pronounced effect. Drying the cysts 

 at room temperature for a period of two, three, or four weeks reduced 

 the population about 9%. He never did get all the nematodes in the 

 cysts completely killed by this method, but it is quite evident that 

 desication is a very important factor in the survival of this nematode. 



Hot-water treatments were worked out for the growers who wished to dig 

 bulbs and to sell them. While I do not remember the details, this 

 likewise has been published in Phytopathology, if you desire specific 

 information. The combination of hot-water-formalin treatment for a 

 given period of time was found very effective in eradicating the nema- 

 tode on bulbs. Also, a chemical material called Dowcide D, at given 

 concentrations and at varying periods of time, proved effective. Thus, 

 we did have a means of treatment vjhereby the growers could sell or 

 move their bulbs. I would like to stress that the bulbs are not a 

 host for the nematode. They could be a source of spread— the nematodes 

 as contaminents adhering to the biilbs. 



Another line of research that was started was a five-year rotation pro- 

 gram. This was set up last year. We are in the second year with that 

 now, and, while Dr. Skotland initiated the work Dr. Ross is now in 

 charge of it, as Dr. Skotland left for another assignment. 



The rotation consists of cowpeas, which are not a host, and soybeans. 

 The experiment is set up over a five-year period, in which soybeans in 

 some plots will be planted continuously. Other plots will be planted 

 in one year rotations of soybeans, followed with cowpeas; two years of 

 cowpeas, followed with soybeans; three years of cowpeas, followed with 

 soybeans; and so on. 



I visited the plots last week and observed that there are some very 

 striking differences already evident in plots that were of soybeans 

 last year and are planted with s oybeans again this year, as compared 

 to rotated crop plots. I believe that I will be safe in saying that 

 not a single bean will be produced on those plots. The plants were 

 about four inches high and had a yellow chlorosis. I doubt that they 

 will live throughout the season. On the other hand, in the plots that 

 were planted in'cowpeas last year but have been planted in soybeans 

 this year, in other words, just one year of a non-suscoptible crop, 

 the soybeans are about knee-high and look as if thny will make a good 

 yie]d. I would like to mention that this field in which this expcri- 



