BULLETIN 1058, U. S. DEPARTMENT OF AGRICULTURE. 



Table III. — Counts of sterility observed in oat panicles collected at random in a field of 

 Wisconsin Pedigree 1 {Wisconsin Wonder), at Madison, Wis., July 21, 1920. 



[The extreme and 



average 



percentages of sterility are shown in 



boldface figures.] 







Normal and sterile spikelets counted. 





Bundle 1. 



Bundle 2. 



Bundle 3. 



Panicle. 



Total. 



Nor- 

 mal. 



Sterile. 



Total. 



Nor- 

 mal. 



Sterile. 



Total. 



Nor- 

 mal. 



Sterile. 





Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



Num- 

 ber. 



Per 

 cent. 



No.l 



45 

 53 

 38 

 44 

 40 

 40 

 42 

 41 

 34 

 38 

 42 

 60 



42 

 45 

 27 

 42 

 32 

 39 

 38 

 37 

 25 

 32 

 39 

 48 



3 



8 

 11 

 2 

 8 

 1 

 4 

 4 

 9 

 6 

 3 

 12 



6 



15 



28 



4 



20 



2 



9 



9 



26 



15 



7 



20 



40 

 50 

 43 

 32 

 65 

 37 

 31 

 38 

 55 

 41 

 54 

 54 

 50 



34 

 45 

 38 

 28 

 41 

 33 

 29 

 34 

 41 

 35 

 37 

 37 

 35 



6 

 5 

 5 

 4 

 24 

 4 

 2 

 4 

 14 

 6 

 17 

 17 

 15 



15 

 10 

 11 

 12 

 37 

 10 

 6 



10 

 25 

 14 

 31 

 31 

 30 



67 

 51 

 82 

 61 

 85 

 72 

 75 

 93 

 62 

 62 

 77 

 73 

 81 

 69 

 90 

 76 

 78 

 65 

 51 

 78 

 72 

 45 

 48 

 43 

 49 

 47 

 53 

 72 



52 

 41 

 58 

 45 

 60 

 54 

 49 

 66 

 52 

 46 

 62 

 40 

 52 

 45 

 67 

 53 

 55 

 50 

 35 

 59 

 54 

 34 

 37 

 29 

 40 

 35 

 40 

 56 



15 

 10 

 24 

 16 

 25 

 18 

 26 

 27 

 10 

 16 

 15 

 33 

 29 

 24 

 23 

 23 

 23 

 15 

 16 

 19 

 • 18 

 11 

 11 

 14 

 9 

 12 

 13 

 16 



22 



No. 2 



19 



No. 3 



29 



No. 4 



27 



No. 5 



29 



No. 6 



25 



No. 7 



34 



No. 8 



29 



No. 9 



16 



No. 10 



25 



No. 11 



19 



No. 12 



45 



No. 13 



35 



No. 14 









34 



No. 15 

















25 



No. 16 

















30 



No.17 

















29 



No. 18 













23 



No. 19 





i ._ 











31 



No. 20 

















24 



No. 21 







1 











25 



No. 22 







1 











24 



No. 23 







1 











23 



No. 24 

















33 



No. 25 

















18 



No. 26 



















25 



No. 27 





; | 











24 



No. 28 













25 







1 



" " 









Average 



43 



37 



5 



13 



45 1 35 



1 



9 



18 



67 



48 



18 



26 



The panicles recorded in Table III were collected on July 21 with- 

 out regard to sterility from an acre plat on the agricultural grounds 

 of the University of Wisconsin. It was noticeable that every panicle 

 showed some sterility, the amount varying from 1 spikelet per panicle 

 in bundle 1 to 33 spikelets per panicle in bundle 3. This field from 

 which the panicles were taken was practically free from halo blight. 

 There were no lesions on the upper leaves, flag leaves, or panicles, 

 and only an occasional lesion on a lower leaf could be found. In the 

 case of this variety there seems to have been no connection what- 

 ever between the halo blight and the sterility recorded above, yet 

 in bundles 2 and 3 the average sterility was more than a third of the 

 whole number of spikelets. 



In the 1920 experiments (Table IV), as in 1918, water and bac- 

 terial suspensions sprayed into oat sheaths produced more sterility 

 than occurred naturally. The average of 21 per cent of sterility on 

 untreated plants is high, but this increased to 40 and 52 per cent 

 when water was sprayed into the sheaths and to 44 and 63 per cent 

 with bacterial suspensions. In this experiment the bacterial sus- 



