Respiration of Cereal Plants and Grains.*

Respiration in frost-damaged wheat has been observed by us1 to be at a higher level than in normal or sound wheat of the same moisture content. This was believed to be due, in part at least, to the higher percentage of dextrose and other simple carbohydrates in the frozen wheat. It then appeared desirable to determine the effect of sprouting upon the respirat,ion of the grain, to ascertain whet’her or not, t.his form of unsoundness in bulk grain could be expected to affect its keeping qualit,ies. A quantity of normal hard spring wheat was divided into three port’ions: one of which was w&ted and allowed t,o sprout for 24 hours in t.he room at a temperature of &20°; t’he second was sprouted under the same conditions for 48 hours; while the third was used in its original state as a control. The sprouted wheats were rapidly dried by spreading them out in a t’hin layer and blowing air over and t,hrough them with an electric fan. They were thus reduced t,o a moisture content of about 12 per cent. Each of the three samples was divided, and t,he several portions brought to different percentages of moisture by the addit’ion of varying quant.ities of water. After standing for 3 days each of these was sealed in a tower, incubated at 37.8”C. for 4 days, and the respired COz determined. Chemical analysis of the several samples showed the normal wheat to cont,ain 0.16 per cent of reducing sugars (calculated as