218 



[September, 1912. 



A NEW DISEASE OF THE CEARA 

 RUBBER TREE. 



A new serious disease of the Ceara rubber tree {Manihot Glaziovii) is 

 recorded in the Tropenpflanzer for February, 1912, by Dr. Ule, who has 

 recently visited Ceara in order to investigate the conditions of rubber 

 production in that country. It is characterised by the production of large 

 swellings on the twigs and blanches, often more than four times the 

 diameter of the branch attacked. Most of the swellings give rise to a 

 number of young shoots which in some cases form "Witches Brooms.' 

 The cause of these deformations is a rust fungus, Uredo Manihotis P. 

 Henn., which was originally discovered on wild Manihots in Brazil in 1892. 

 It occurs on the leaves as well as on the stems, but in the former situation 

 it forms only the customary rust spots. Swellings are for med when it 

 attacks the stem because, according to Ule, the mycelium of the fungus 

 stops the flow of sap. No other stage of the fungus has yet been discov- 

 ered, and it is therefore not known whether it requires an intermediate 

 host plant to complete its development. The disease is widespread 

 throughout the whole Serra de Baturite, in the plantations along the 

 railwpy, and in the Serra de Maranguape ; and Ule considers it probable 

 that it occurs throughout the whole of Ceara and Rio Grande Do Norte. 

 When trees are attacked by the disease, the flow of latex diminishes, the 

 diseased branches die off, and finally the tree succumbs. Ule considers that 

 there is little danger of spreading the disease by the distribution of seed, 

 but cuttings should be taken only from sound trees. This opinion is quite 

 contrary to the generally accepted view that Hemileia vastatrix, a similar 

 fungus, was spread from Ceylon with coffee seed, either on the seed or in 

 the packing material, to other countries in the East; and it would 

 appear advisable that countries importing seeds from Ceara should 

 insist on disinfection. 



The fungus is known to occur on Manioc, Manihot utilissima, as well 

 as on Manihot Glaziovii. 



T. P. 



ESTIMATE OP THE AREA UNDER COTTON IN AUGUST. 



Province^ ^nd States. 



1012-1913. 



1911-12 



1910-11. 



Bombay (Deccan)(a) 



... 1,357,000 



.. 1,467,000 . 



.. 1.545,000 



Central Provinces and Berar 



... 4.222,000 



.. 4,135.000 . 



.. 4,491,000 



Madras 



60,000 



136.C00 



136,000 



Punjab (a) ... 



... 1,228,000 



.. 1,322.000 . 



.. 1,285,000 



United Provinces 



(b) 



(b) 



(b) 



Burma 



192,000 



179,000 



168,000 



Bengal 



50,000 



63,000 . 



'.'.\ 161,000 



Bihar and Orissa 



80,000 



85,000 . 



Assam 



35,000 



36.000 . 





N.W. Frontier 



48,000 



45,000 



31,000 



Ajmer-Merwara 



14.000 



18,000 



24,000 



Hyderabad 



... 2.213,000 



... 2,509,000 



... 2,833,000 



Central India 



... (c) 675,000 



... (c) 747,000 



.. 1,285,000 



Rajputana 



...(d) 236,000 



...(d) 230 000 



384,000 



Mysore 



11,000 



6.000 . 



12,000 



Total 



...10.421,00U 



10,978,000 



12.355.000 



(a) Including Native States, (b) Figures not reported, (c) Excluding Gwalior and 

 Baghelkhand States ( Report just received for Baghelkhand shows 28,000 acres sown.) 

 (d) Excluding Mewar and Bundi States. 



