1923] 



LEHMAN — POD AND STEM BLIGHT OF SOYBEAN 137 



Pods, leaves, and stems were atomized with a spore suspension. 

 Pot 19 contained 2 plants bearing 15 pods in the same state of 

 maturity as the plant in Pot 21. Pods, leaves, and stems were 

 atomized with a spore suspension. Pot 10 contained 1 plant 

 bearing 11 pods, the oldest being still green but just at the point 

 of turning brown. All were atomized with a spore suspension. 

 Pot 17 contained 2 plants; one with 8 pods was inoculated by 

 inserting mycelium into pod walls; the other, by laying mycelium 

 on unwounded pod. Pot 18 containing 2 plants with 20 pods 

 was used as a check, a part of the pods being wounded by pushing 

 tweezer point through wall. Strain 13 was used for these inocu- 

 lations. The plants were covered with bell jars and shaded 

 from direct sunlight. By July 1, infection was apparent on all 

 wounded pods of Pot 17, pycnidia being present on most of them. 

 One unwounded pod showed definite infection. The bell jar 

 was removed on this date. By July 7, 3 unwounded pods of 

 Pot 17 had become infected. No infection was apparent on 

 stems or pods of Pots 21, 18, and 10, but the leaves of these 

 plants possessed marginal areas of dead tissue dotted above with 

 many pycnidia. It was very apparent that the causal organism 

 was advancing into uninvaded tissue. The bell jar was removed 

 from Pot 10 on this date. By July 13, pycnidia were present on 

 a few and infection was evident on most of the pods of Pots 19 

 and 21. The stems and most of the petioles were still green 

 but most of the leaves had fallen. Pycnidia were numerous 

 on stems in Pot 10, but none were present on pods. The plants 

 of Pot 18 were entirely free from disease at this date. 



On June 27, the plants in 2 more jars were inoculated. Pot 

 31 contained 2 plants. The older of these was beginning to 

 mature, as indicated by the formation of yellow-brown color 

 in the 12 pods and in the leaves. The younger plant had 23 

 pods, the largest being full-size but still green. The leaves 

 likewise were green with no indication of turning. These plants 



spraying with a spore suspension. Pot 27 

 one with 9 yellowing pods, the other with 



inoculated by 



pods, with no indication of yellowing, wj 

 mycelium on unwounded pod walls. Th 

 ;re kept under bell jar and shaded from 



both 



