178 PHYT0PHTH0RA PARASITICA. 



of seed worth Rs. 16,499,640. The oil is greatly used in the manufac- 

 ture of the famous Turkey-red. Again its medical properties secure 

 for it an extensive trade. In many parts of India it is used as a 

 luminant as it gives a bright smokeless light, Especially in Austra- 

 lia and some other places it finds a wide use as a lubricant, It is 

 also employed for dressing tanned hides and skins. The castor 

 oil-cake is an important constitutent of manures. In Assam the 

 plant is cultivated for feeding the eri-silk worm on its leaves. The 

 growing cottage en-silk industry will necessitate its wider cultiva- 

 tion for this purpose. 



Though the castor oil plant is so widely distributed still no 

 important fungus pest, except the rust, 1 has been recorded as 

 attacking this crop ; it has been considered to be comparatively free 

 from fungus enemies, and yet two serious pests occur at Pusa, 

 One is Phytophthora parasitica no v. spec, the other a species of 

 Cercospora. The latter is confined only to leaves and so does not 

 prove fatal to the plant. In wet weather this disease is a serious 

 menace to the cultivation of this crop for the en'-silk industry, 

 as about ninety per cent, of the leaves of old and young plants are 

 sometimes covered all over with Cercospora spots. To a greater 

 or less extent this disease is present all the year round. 



In the wet months of August and September Choanephora 

 attacks leaves, growing points and tender shoots. This parasite 

 sets up a rot in the affected parts. 



There is also an Altemaria found occurring on the leaves which 

 might be parasitic. 



All these diseases will be dealt with in another paper when their 

 study is completed. 



Phytophthora on castor was first found at Pusa in the year 1909 

 in August. Since then it has been found appearing every year about 

 the end of June, after the rains have set in. Last year (1912) it 

 appeared as early as June on account of the frequent showers of 



1 Ajrekar, S. L. The Castor rust (? Melampsorella Ricini, de Toni). Jour. Bombay Nat. 

 Hist. Soc. 1912, p. 1092. 



