MYSTROSPORIUM 55 



Conidia and conidiophores olive-brown. Conidia muri- 

 form, minutely warted, somewhat irregular in form, 25-33 x 



16-22 /JL. 



Malkoff, Von K., Zeit. Pflanzenkr., 12, p. 283 (1902). 



MYSTROSPORIUM (Corda) 



Conidiophores simple or sparingly branched, short, rigid, 

 brown ; conidia elongated, variously muriformly septate, dark 

 coloured. 



Closely allied to Macrosporium, differing in the darker 

 coloured, rigid conidiophores and conidia. 



Iris bulb scab {Mystrosporium adustum, Massee) some- 

 times destroys the bulbs of Iris reticulata by forming large, 

 black, crusty patches on the outer sheath, the mycelium 

 reaching to the heart of the bulb. 



The hyphae form a dark-brown crust, some of the cells are 

 often much swollen ; conidia elliptic-oblong or ovate, ends 

 obtuse, 5-7-septate, becoming muriform, sometimes with 

 transverse septa only, 45-60X20-22 /a, smooth, dark brown, 

 solitary on the tips of short branches. 



I have found that if bulbs are only slightly attacked, that 

 soaking for two hours in a solution of one part formalin to 

 three hundred parts water will destroy the fungus without 

 injuring the bulb. On the whole, however, it is wiser to 

 destroy all infected bulbs, rather than run the risk of infecting 

 the land. 



Mystrosporium alliorium (Berk.) sometimes forms dark 

 patches on onion bulbs. 



Conidiophores brown, septate, often flexuous, conidia 

 terminal or lateral, elliptic-oblong or subpiriform, constricted 

 in the middle, becoming multi-septate and muriform, epispore 

 brown, minutely warted, 30-45x8-12 /j.. 



Mystrosporium abrodens (Neuman) is destructive to the 

 wheat crop in some districts in France. Dark patches appear 

 on the leaves and nodes, the latter become weak and the 

 plant bends over. The ears are arrested. 



Neumann, Soc. Biol. Toulouse, 1892. 



