the under surface of the leaves, and the disease may often 

 prove to be very destructive if it is allowed to go on 

 unchecked. 



The disease has been recorded in the United States of 

 America and in Japan. 



Spraying with dilute Bordeaux mixture or with a solution 

 of " liver ot sulphur" is an effective remedy. 



Diagnosis : — Forming very delicate patches on the under 

 surface of the leaf white ; conidiophores dichotomously 

 branched, ultimate branches acute, straight, spreading ; 

 conidia hyaline, elliptical, 25-32 by 18-20 microns. 



MASSEE : Text Book of PI. Dis., p. 80, 1907. 



Berk, and Curt. : Joum Linn. Soc. Vol. X., p. 363. 



PERONOSPORA HYOSCYAMI, De Bary. 

 (Tobacco Mildew). 



The fungus is a destructive parasite on cultivated 

 tobacco in Queensland ; it has also been reported from 

 California. 



Spraying with dilute Bordeaux mixture has been found 

 to be effective in checking the spread of the disease. 



Diagnosis: — Forming dirty, greyish-violet tufts on the 

 under surface of the leaf ; conidiophores 300-500 microns 

 high, 5-8 times dichotomously branched near the apex, 

 ultimate branches diverging, short and awl-shaped ; conidia 

 small, elliptical, ends obtuse, pale dingy-violet, i5.24.by 13-18 

 microns ; oospore unknown. 



MASSEE : Text Booh of PL Dis. p. 81 , 1907. 



DeBarY: Ann. Nat. Sci. Vol. XX., p. 123. 



PYTHIUM PALMIVORUM, Butler. 

 (Bud Rot of Coconut.) 



In addition to the coconut the fungus also causes a 

 disease of palmyra and areca palms in India. 



The first symptom is the turning white of a whole 

 leaf situated usually near the centre of the " crown." 

 Next, the unopened leaf in the centre of the " crown " 

 becomes likewise discoloured. Finally, the central shoot 

 rots and the whole crown falls. When a plant is once 

 attacked it rarely recovers. 



BUTLER : Memoirs of the Pusa Institute, Bull. No. 9, 

 1908. 



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