7i4 



Journal of Agricultural Research 



Vol. XX, No. 9 



They were carried through storage and examined on February 18, 191 9. 

 The results are given in Table VI. 



Table VI. — Relation of smudge to sprouting of onion sets in storage 

 EXPERIMENT 1 



Condition of bulbs. 



Total 

 number of 

 bulbs used. 



Healthy. 

 Diseased . 



47 

 49 



Number 

 sprouted. 



14 

 26 



Percentage 

 sprouted. 



29.7 



53- o 



Experiment 2. — The sets used in this experiment were sown late in 

 the spring and consequently were not harvested until about September 

 14, 1918. They were allowed to cure in the field in the normal manner 

 until September 30, when they were placed in storage. Three average 

 crates were selected at this time and kept under observation. At har- 

 vest time smudge was prevalent only on the dry outer scales of the sets, 

 but during the storage period it gradually penetrated the underlying 

 scales. When a final examination was made on March 5, 191 9, it was 

 clear that in nearly every case where the fungus had penetrated deeply 

 the bulb had sprouted and had thus become worthless. A typical 

 example of this condition is shown in Plate 81 , D. An estimate of the 

 amount of sprouting actually due to or intimately associated with smudge 

 was secured by counting 100 to 200 bulbs in each crate. The results 

 are given in Table VII. 



Tabi.E VII.— Relation of smudge to sprouting of onion sets in storage 

 EXPERIMENT 2 



It is not to be construed from these data that smudge is always the 

 chief cause of premature sprouting of onion sets in storage, since un- 

 questionably other factors may often be entirely responsible. One of 

 these, the neckrot decay of the scales, commonly produces a similar effect. 

 It is apparent, however, that the invasion of the bulb scales by the smudge 

 fungus brings about some physiological change which promotes growth 

 of the previously dormant bud. 



