EXERCISE XXV. 

 SEED CORN TESTING. 



Supplies for a Laboratory Section of Twelve. Seventy-two ears of corn ranging from very poor to good 

 quality ; twelve cigar boxes lettered A, B, C, etc. ; two yards of cheese cloth ; two yards of closely wcven muslin : 

 twelve rulers : twelve soft blunt pencils for ruling on cloth ; two pairs of scissors ; wet sawdust sufficient to nil 

 twelve cigar boxes and the germination box (30x30x4 inches) to a depth of about two inches. One hundred ears 

 of ordinary seed corn numbered 1, 2 3, etc. Germination box (30x30x4 inches). 



Part A. The Relation of Certain Kernel Defects to Germination. 



DIRECTIONS. Fill a cigar box about 2/3 full of wet sawdust. Cut a piece of cheese 

 cloth and a piece of closely woven muslin the size of the box. With a ruler and pencil mark 

 off six equal sized divisions on the cheese cloth. Number and letter these divisions as is 

 shown by the following figure. 



(The lettering is correct only for the cigar box lettered A.) 



~KT 



AT 



J^T 



A4 



A5 



A6 



Wet the cheese cloth and lay it smoothly over the sawdust. Now letter and number six 

 ears of corn to correspond with the six divisions ruled on the cheese cloth. This may be 

 done by driving a pin or shingle nail through a small piece of cardboard, properly labeled, 

 into the cob at the butt of the ear. 



Remove six kernels from each ear, two from opposite sides, near the butt, likewise two 

 from the middle and two from near the tip. Prior to shelling corn for seed a certain per cent 

 is "nubbed" from both butt and tip and discarded. In removing the kernels for this test, 

 therefore, use only from the parts of the ear that would be used as seed. Place the six 

 kernels in the divisions corresponding to the numbers of ears. Wet the piece of muslin and 

 lay ft over the kernels. Scatter moist sawdust yi inch deep over the muslin and set the 

 box aside in a moderately warm place (65°-100° F.) where it will not be disturbed. It will 

 be necessary to watch moisture conditions within the box from day to day. 



1. After completing the above, remove six more kernels from each ear. Carefully ex- 

 amine these kernels, particularly the hulls and germs, to determine whether or not there 

 are any indications of lack of viability. Your notes may be recorded in the following form: 



81 



