Uv\K BU<;ilT 



COFFEA 



ARABICA 

 Diseases 



Ruin of Ceylon 

 Plantation*. 



ility to borer may be increased, but leaf-blight brought under control. On 

 me soils, under certain climates, or with particular exposures, leaf-blight never 

 been serious, and, moreover, either the plants are now better able to with- 

 1 isease or its virulency is being attenuated, because in South India coffee- 

 ting is by no means impossible, in spite of blight and borer. The low prices, 

 ugh overproduction in South America, are far more serious than all the 

 ''I) Jits at present known. There would seem little doubt that had the Ceylon 

 planters cultivated and manured their estates more thoroughly and systematically 

 than they did their industry might have been saved. When the disease ap- 

 peared both soil and plant wore exhausted. The rapidity of the destruction that 

 fiisnrd may be thus demonstrated: average yield for the years 1866-8, all over 

 tin- i.sland (that is, before J*-HI<*-< appeared), was 4'28 cwt. per acre; in 

 S7--4 it had fallen to 2'93 cwt. per acre, and in 1878 to 2 cwt. per acre. 



2. American Coffee Disease, Stillunn /ftn-i(fuin, Cooke ; Massee, I.e. 



eomte, I.e. 204; Juraelle, I.e. 377. 



" This disease is almost as destructive to the coffee industry in the New World 

 ii, -mill- in i-iiNintrij,- is in the Old World." " The symptoms of the disease 

 unmistakable ; circular whitish blotches occur on the leaves, often in con- 

 irablo numbers, and are equally marked on both surfaces. Using a pocket- 

 ;, very minute fungi resembling a miniature pin in shape, and of a clear yellow 



our, can be seen grouped on the spots on the upper surface of the leaf. The 

 ies are also sometimes attacked, being marked with circular spots. On the 



ung shoots the pale diseased spots are elongated" (Massee). As this disease 

 not appeared, so far as is known, on the coffee of Asia, we have the somewhat 

 ificant fact of two coffee blights, the one confined to the Old and the other 



the New World. A species of stllbmn does considerable injury to the tea, being 

 Thread Blight of tea planters. \Cf. Peata and Blights of Tea, 392.] 



3. Leaf-rot. This leaf-blight was described by Cooke under the name Leaf-rot. 

 flli<-til(U'i(t /lofcrof/d, the specific name being the vernacular for the 



lease. [Of. also Tubeuf, I.e. 518 ; Lecomte, I.e. 203.] It is said to be 



talent in Mysore during July ; the leaves, flowers and berries become 

 vered with a shiny gelatinous substance which turns black about the time 



,t the affected parts fall from the plant. 



Cameron thinks that continuous or heavy rainfall, dense shade, drip, and 

 .ation of drains favour the development of this blight. Improvements 

 combat these defects are beneficial. All affected leaves should be burned or 



ited with flowers of sulphur. As seen in the Kew Herbarium the leaves are 

 vered with a simple mycelium much as in stuiumi, but without any fructifica- 

 ms. Samples of it have come from the coffee plantations in Venezuela, Costa 

 ica and Jamaica, as well as Mysore, so that it is fairly widespread and should 

 commence to assume its complete form, may become a serious pest. It should 

 irefore be kept under control and carefully studied. 



4. Coffee- twig Disease, Necnt or decret-utt, Massee, I.e. 327. This 

 ig Disease is said to be a destructive parasite on coffee trees at Selangor. 

 commences at the tips of the young branches and extends downwards. 



ursting through the epidermis of the shoots are minute white spots, which 

 n become orange-red in colour and gelatinous in texture. The twigs 

 ereafter turn black and thus appear as if syringed with acid, while at 

 e same time the bark splits as in canker. 



During my tour through Coorg and the Wynaad I was shown a disease that 

 to mind the Malay twig disease or canker just described. The tips of the 

 iting shoots, including a large number of leaves and berries, become withered 

 " dried up, and in due course turn black. I was unable to discover on these any 

 s, but obviously should have visited the plantations at a much earlier season 

 the year in order to study the distressing disease indicated. The withered 

 its, if gathered along with the ripe cherries, greatly lower the value of the crop, 

 so that they are not only a serious loss but a source of danger through their 

 being inadvertently collected. The Indian planters regard the blackened and 

 withered shoots as a consequence of a want of general tone and vigour, and as 

 proceeding from poverty of soil rather than being due to any specific disease. An 

 inspection of the specimens preserved at Kew leads me, however, to suspect 



385 25 



Twig Disease. 



Withered and 



Blackened 



Berries. 



