THE FUNGUS PESTS OF 

 CERTAIN FLOWERS 



X-400 



FUNGUS OF SENECIO DISEASE 

 Uredo senecionis 



Cineraria and Senecio Disease. Senecio pulcher, soon 

 after its introduction into England, was attacked, and in some 



gardens completely destroyed, 

 by a fungus named Puccinia 

 glomerata, or rather the Uredo 

 stage of this fungus with 

 simple, not compound, spores. 

 The fungus is well known, 

 being closely allied to that 

 which causes the rust or mil- 

 dew of corn crops. It is very 

 common on the wild species 

 of Groundsel in England, being especially frequent and virulent on 

 the Ragwort Groundsel, Senecio Jacobea, from August to October. 

 The leaves of infected plants are covered with rust-coloured dusty 

 pustules, the Uredo condition of the fungus, and known in this stage 

 as Uredo senecionis, sometimes termed Trichobasis senecionis. The 

 fungus has a Puccinia stage of growth very similar to that of the 

 Hollyhock fungus, Puccinia malvacearum. 



At A is illustrated a fragment of a leaf of Senecio pulcher^ natural 

 size, and covered with the orange-coloured fungus; at B a small 

 part of a Uredo pustule as seen bursting through the cuticle of the 

 Senecio leaf. 



No remedial measures for the extirpation of this fungus are 

 known, but as garden Senecios and Cinerarias are infected by dis- 

 eased plants of Wild Groundsel, it is desirable that plants of the 

 latter (especially when diseased) should be destroyed. Weeds in and 



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