118 MORPHOLO ;Y and PARVSITISM or RHIZOCrONMA. 



I'ut.itu .. .. Sniiiniim liibtro«um, 



I Swcot Ptitnto I iHimiTii hnliilan. 



I'liiiipkin .. Ciicurbilii /ifpo. 



WaliT Melon •• filriiltim vulgnrii. 



ti;irilcn Pi-n . . I'lKitm mlivum. 



UiiiiTiiP .. .. •• Mtdioijo sail I'll. 



The fungus frequently attacks the host in the seedling stage, 

 anrl the siniilarity to the damping off caused by Pijtitiinn renders it 

 not improbable that many cases of disease have been wrongly attrib- 

 uted to the latter genus. In India Rhizoctonin appears to have a 

 wide range of hosts ; in the past year the following plaiils were 

 attacked on Pusa Farm- - 



( Inmiicl mil .. .. .. .. Ainchis linixjgwn. 



( 'i)W Poa . . . . . . . . Vigna rnliiing. 



.hitc .. .. .. Corrhonix cnp-iiiliiriii. 



S<iy B<'an . . . . Cllijrinr mjn. 



IkilirhoH UihUih 



Trirhinnitithis rurmitfriii/i 



Mulberry Muni/i iilh'i. 



It has also been found on ground nut and scsanio at Surat. on 

 melon roots at Peshawai-. on cotton at ('awnj)or(' and on loots of 

 Af/aiT iKjidd in .Mailias. Some fifteen years ago Cunningham (7) 

 described a root rot of lucerne and a disease of potato stems known 

 as '■ Bangle blight."" both of which he attributed to the attack of a 

 sclerotial fungus. Judging from his description and figures, the 

 fungus was most probably R. soUiiti Kiihn, but in his memoir it was 

 not identified. The fact that a disease of potato tubers due to the 

 attack of /<■. fiohtm Ki\hn iskuown to occuriu l5aid<i])ort' strengthens 

 this \ne\v. 



In the rains of 1910 a severe outltreak of the disease took j)lace 

 on Pusa Farm, and the present research was undertaken to discover 

 what species of the fungus was present in India and whether any 

 specialisation existed in its parasitism on different hosts. The 

 association of a basidiomycete resembhng Cnrticium rafjtrui 

 with the /?// /zor/ou/a also gave a favourable opportunity for investig- 

 ating the connection between the two. The most iinj)oitaiit crops 

 attacked were ground mit, cow pea, jute and cotton, and it was 



