Tech. A:5 



D. Sample Processin;^ Equipment: 



Processing plant or soil samples to recover tivi nematodes pres- 

 ent involves separating the nematodes from the soil particles or 

 plant tissues, getting the nematodes into suspension in water, 

 and then concentrating the nematodes into a small voliune of v/ater 

 for examination and for other purposes. Various means of accom- 

 plishing these three steps have been devised and have been used 

 in different combinations. The equipment involved can be very 

 simple, as is described here, or it may take the form of machines, 

 usually utilising the saiiie principles, but requiring more descrip- 

 tion than space herein will allow. 



1. A blendor , such as the Waring blender or its equivalent, is used 

 for facilitating the rapid recovery of nematodes from plant tis- 

 sues, which are reduced to small fragments by the blendor. 



2. Pails or pans for containing soil and water are used for the 

 decatitation-sieving method. Galvanized pails which neat together 

 are more durable and space-saving than enameled pails. The 12 

 quart size is satisfactory. Four to srx containers should be 

 obtained with two as the minimum. Plastic pails are suitable. 



3. Sieves in a series of meshes of 2$, 60, 200, and 270 should be 

 acquired. The addition of a 100 and a 325 mesh sieve may be 

 desirable, but it is not necessary. The eight-inch diameter, nest- 

 type sieve is stocked by all scientific supply companies. A 

 smaller five-inch type is available from some companies, but will 

 not be as generally useful as the larger size. A set of small 

 sieves of about two or three-inch diameter for use in rjpid re- 

 moval of nematodes from small samples is useful to have but is 

 not commercially stocked. Such a set is easily made by solder- 

 ing, fusing, or cementing sieve screening to small tin or plastic 

 dishes or suitable size and shape. 



U. Sieve supports will eliminate the need for holding a sieve by 

 hand while pouring the nematode-soil suspension in water through 

 it. A simple, effective support can be made by shaping aluminum 

 clothesline wire into the form of a ring the size of the sieve, 

 with three or four lugs twisted outwards around the border. In 

 use, the sieve fits in the ring which is then placed over the 

 pail or pan and is supported there by the lugs. Similar sieve 

 holders can be made of wood or metal strips. Another possibility 

 is to make a stand to hold the sieve over the container. 



5. Funnels are used for isolation of nematodes from soil and plant 

 materials; this m.uch used item, of equipment is referred to as the 

 Baerinann funnel. In its simplest form, the Daermann funnel con- 

 sists of a fimnel with a short piece of flexible tubing attached 

 to the stem and a clamp to close the tubing. The sample is 

 either supported on or enclosed in a porous material and immersed 

 in water with which the funnel is filled. Separation of the 



