FusARiA OF Potatoes 



243 



On slightly acidified hard potato agar, culture fifteen days old; conidia 



from a sporodochium : 



Conidia: 1-septate, 0.5 per cent, 18 x 5.2 (14-22 x 4.7-5.9)^ 

 2-septate, 5.5 per cent, 23 x 6.9 (20-26 x 6.4-7.9) /x 

 3-septate, 34 per cent, 26.5 x 7 (21-33 x 5.6-7.6) /x 

 4-septate, 38 per cent, 33.2 x 7.3 (26-38 x 6.4-7.9);u 

 5-septate, 22 per cent, 36.4 x 7.5 (31^4 x 7-8.8) /z 

 6-septate, very few, 44.5 x 8.9yLi (only one measured) 



Fig. 43. — Fusarium culmorum var. leteius. a, Conidia, B, conidiophores, from aerial sporo- 

 dochium from 1 5-day s-old culture on slightly acidified hard potato agar; c, conidiophore from 

 11-days-old culture on hard lima-hean agar; d, conidia from plectenchymic sporodochium, e, f, g, 

 conidiophores, from 72-days-old culture on red raspberry cane plug; H, intercalary chlamydospores 

 from 17 5-day s-old culture on corn agar; i, conidia from plectenchymic sporodochium from 11- 

 days-old culture on hard lima-hean agar; 3, intercalary chlamydospores from 17 5-day s-old culture 

 on corn agar {some chlamydospores producing conidiophores); 'k, conidia from aerial sporodochia 

 from 72-days-old culture on red raspberry cane plug; L, tip of aerial hypha showing prominent 

 swellings {magnification 250 times) 



On red raspberry cane plug, culture seventy-two days old: 

 (1) Conidia from a plectenchymic sporodochium borne directly on the 

 plug 

 Conidia: 3-septate, 14 per cent 

 ' 4-septate, 20 per cent 



5-septate, 66 per cent, 43 x 6.2 (31-53 x 5.8-7)/x 



