4 Bacterial Disease of the Mango 



and this would seem to point to the fact that the disease was not known 

 in Natal at that time. This idea was confirmed by a statement made 

 by Dr Medley Wood, who was, until recently, Director of the Durban 

 Botanic Gardens, and who informed me that whereas some years back 

 he sold mangoes from the trees in the gardens up to the value of £30, 

 recently he had scarcely obtained sufficient for his own use. 



In August, 1911, an inspection of the mango trees at the Tzaneen 

 and Westphalia Estates in the Zoutpansberg District showed them to 

 be quite free from this trouble. 



This disease was noted on some mango fruits from Lourenco Marques 

 in November, 1910; but in Portuguese East Africa would appear to be 

 confined to the neighbourhood of Delagoa Bay ; for in a letter dated 

 14th November, 1913, Mr Pole Evans writes: "When I visited Portu- 

 guese East Africa in September last, I saw some of the largest mango 

 trees that I have ever seen at Quilimane and Inhambane. The trees 

 were then in flower. I examined carefully for any disease that might be 

 present, and saw no evidence of the bacterial disease. The inhabitants 

 told me that the trees bore well and that the fruit was clean." 



In the absence of any reference in available literature to any disease 

 at all resembling the one under discussion, an attempt was made by 

 various means to discover whether it occurred outside South Africa 

 or not. 



The symptoms accompanying the disease, which are very charac- 

 teristic, were described to Dr Erwin F. Smith of Washington, and 

 he stated that he was not aware of the existence of such a disease in 

 America. 



With reference to the possible occurrence of this trouble in India, 

 Dr E. J. Butler, Director of the Imperial Agricultural Research Institute, 

 Pusa, in a letter dated the 29th February, 1912, writes as follows: 



"Last year for the first time a supposed bacterial disease of mango 

 fruits was reported from the Bengal Agricultural College, Sabour, 

 Bhagalpur. The Indian Assistant Professor of Mycology who examined 

 the disease could find no fungus in the rotted spots on the fruit. Bacteria 

 were naturally present, and he attributed the damage, which was con- 

 siderable, to this cause. Some fruits were sent to my Laboratory and 

 on examination I found the common Gloeosporium Mangae 'Noack 

 (probably G. Raciborski, common on the leaves) together with a little 

 of a Hendersonia which we have previously found associated with a 

 mango fruit rot. I found no evidence to support the idea that the 

 disease was bacterial." 



