Oct. 1, 1899.] THE TROPICAL 
AGRICULTURIST. 
235 
TEA AND COFFEE DISEASES. 
(With Plate.) 
Brown Blight of Tea. 
The " blights " which afiect tea in Assam were 
investigated and described in the Kew Bulletin for last 
year (pp. 105-112). Another and different one has 
made its appearance ia (Jeylon, and has been trans- 
mitted to Kew for investigation by BIr. J, C. Willis, 
M.A., F.L.S., Director of ths Royal Botanic Gardens. 
DiBECTOK, Royal Botanic Gardens, Peradeniya, 
Ceylon, to Royal Gardens, Kew. 
Royal Botanic Gardens, 
Peradeniya, Ceylon, 
April 10, 1899. 
Sir, By parcel post this week I send you a tin 
containing fome specimens of a fungus blight which 
is causing considerable injury to tea iu many of the 
planting districts of Ceylon. It resembles the "grey 
blight " of Assam (which is also common here) in 
its action on the leaf, and I have recommended 
similar measures for ita eradication to those used 
for that pest. The specimens enclosed show the 
conidial fructification of the fungus, and I am sen- 
ding them in the hope that you may be able to give 
me the name of the fungus to enable me to round 
off my investigations into its ravages and life history. 
In the event of your publishing any account of this 
disease, I have to request that the name of the 
estate mentioned on the specimens be withheld from 
publication, 
N.otes upon the disease are given below, 
I am &c,, 
(Signed) John C. Willis. 
The Director, Royal Gardens, Kew. 
Specimens from Maskeliya district, 4,000 feet above 
the sea level, sent to Kew. Fructifying specimens 
pinned. Collected 7th April, 1899. 
Disease like grey blight in appearance and effect, 
but characterised, by chocolate-brown colour of fully 
diseased spots on the leaves attacked. Common in 
the Central Province. 
Shows first on upper side of leaf, and soon after- 
wards on lower also. Appears as yellowish-brown 
patches, which rapidly spread and to a chocolate or 
almost black colour, and as they extent their cen- 
tral parts dry up, die, and often fall out if the leaf 
is roughly shaken. When the leaf is held np to the 
light, a yellowish band, 1-3 mm. wide, is seen round 
the infected area, due to the spreading of the my- 
celium into the still unattacked area of the leaf, 
which losess its green colour. 
Fructifications not often seen ; on the accompany- 
ing specimens they show in typical form, as pinkish 
spots, more or less concentrically grouped. The 
spores are oval-oblong, unicellular, hyaline. The 
blight spreads very rapidly, and does much damage. 
Measures of treatment recommended are the same 
as for grey blight. 
J. C. W. 
JOth April, 1899. 
The specimens were examined by Mr. Massee, the 
Principal Assistant for Cryptogams in the Herba- 
rium of the Royal Gardens. He furnished the fol- 
lowing report: — 
The fungus proves to be undescribed, and may 
be known as CoUetotnchwn Camellice. 
All the many known species of Colletotrichum are 
parasites, and many are destructive to important 
economic plants. 
Spraying with Bordeaux mixture, or with ammo- 
niacal solution of carbonate of copper has proved 
effective in checking the spread of other species of 
Colletotrichum, and would probably prove beneficial 
in the present instance. In spraying plants like 
the tea, having glabrous leaves, success mainly de- 
pends on the fineness of the spray, which should 
hang like a fog. A coarse spray causes the solu- 
tion to form drops which roll off the polished surface 
of the leaves. 
In addition to spraying, all diseased leaves should 
be collected and burned, as Collet at ricMim is a, form- 
genus (—the conidial condition of an ascigerous), 
and if the leaves are allowed to fall and remain 
on I he ground under the trees, the higher form of 
fruit would form on the decaying leaves and in- 
oculate the new leaves the following season. 
G. M. 
3rd May, 1899. 
The following description has now been prepared 
by Mr. Massee : — 
The fungus present on the leaves proves to 
be a species of Colletotrichuvi, a genus perhaps 
too closely allied to Glososponum, differing only 
in the pcesence of a variable number of coloured 
spines being intermixed with the conidiophores. Nu- 
merous species belonging to these genera are known 
as destructive parasites, attacking more especially 
leaves and fruit. 
The leaves of the tea plant are probably infected 
in the first instance by floating spores settling on 
Iheir upper surface when damp. Ihe discoloured por- 
tion of the leaf corresponds to the range of mycelium 
in the tissues. Eventually the central portion of the 
blotch changes to a dull grey colour, and becomes 
studded with numerous very minute black spots, 
which are often arranged in irregular circles. These 
points correspond to the clusters of spores which 
rupture the epidermis of ihe leaf anil become free 
on the surface, whence they are washed by rain or 
carried by wind to other leaves. After the spores 
are mature, those portions of the leaf on which they 
are produced become dry and brittle, and are blown 
about by wind, and as many spores still adhere to 
such floating fragments, it is not difficult to under- 
stand why the disease spreads so quickly when once 
established in a plantation. 
As the species proves to be undescribed, the follow- 
ing diagnosis is given : — 
Colletotrichum Camelliae, Massee (sp. nov.) Maculee 
amphigensB effuso-indeterminalee, primo flavo brnnnes, 
dein nigrescentes, denique griseo-arescentes, postremo 
frnstulatim deciduae ac folium perforatum relinquentes. 
Acervuli ceutro maculie laxe insidentes, epiphylli. 
Conidia cylindraceo-elongata, continua, utrinque obtu- 
sata, hyalina, episporio levi donata, 15-17 M 4-5 u. Cysti- 
rfja lineari-cuspidata, septata, olivacea, 100-135 x 7-8 u. 
Ceylon. Central Province. On living leaves of 
Caviellia Thea. 
Preventive Measures.— 'Bot&e&xix mixture has been 
proved to arrest the spread of disease caused by other 
species of Colletotrichum, as C. lindemuthianum on 
sca.rlet-runners and French beans, C. Althece, on 
hollyhocks, &c., and would probably prove effective in 
the present instance. Care should be taken to experi- 
ment at first with a very dilute solution until iti action 
on the leaves is ascertained. 
Diseased leaves should be picked before the sporei 
are mature ; that is, as soon as the first indications of 
the presence of the fungus are observed. If thii 
practice was universally followed through the infected 
area, the disease could be readily exterminated. 
Central American CoPFEB-Disi ASE. 
This disease has attracted attention for rather more 
than the last twenty years. But it is, perhaps, only of 
late that it has attained serious dimensions. Apparent- 
ly, the first notice is contained in the Keiu Report for 
1876 (p. 21), where it is noticed as " Maucha de liierro" 
or " Iron atain." Berkeley attributed it to a minute 
fungus, Depazea maculosa, which was the only organism 
he could find on the diseased leaves. Dr. Ernst, how- 
ever, in his Estudios sobre las dejormaciones, Enfermede- 
das y enemigos del arbol de Cafe en Venezuela, Caracas, 
1878, was unable to accept this as the cause of the 
malady : — 
" Berkeley opina que la Depazea es causa de U 
' Mancha de hierro,' sin duda porque las hojas que le 
fuel on romitidas, vinierou con esta denominacion. No 
queremos contri'.decir el aserto de tan respetable 
autoridad, pero teudremos mds adelante ocasion de 
comprobar que la enfermedad llamada aaf es geueral- 
mente de otro origin " (p. 17). 
He further expressed the opinion that " iron stain" 
was to be attributed to more than one cause, and that 
