Sept. 1, 1899.] 
THE TROPICAL AGRICULTURIST. 
193 
very slender, straight or flexuous, head globose ; 
conidia elliptical or subglobose, 2-2 5 x 1-5-2 ((. 
This is considered by Spegazzini to be a Basidiomy- 
cete, and renamed Pistillinaflavida', however, I have 
failed to iind basidia, and so prefer to retain the spe- 
cies under Stilbum. 
These are but samples of Mr, Massee's valu- 
able work which we have much pleasure in 
recommending to the attention of our plant- 
ing readers, — a supply of the book is shoi'tly 
expected. 
fy. 
TEA BLIGHTS. 
CIRCULAR FROM THE ROYAL BOTANIC 
GARDENS, CEYLON. 
Tea Blights. — The following notes on tea blights 
have been prepared at the request of Mr. PGA Laue, 
Chairman of the Planters' Association, and to a large 
extent in consultation with him. The immunity 
from disease that tea has enjoyed in so marked a 
manner for many years is now disappearing; 
many insect and fungus enemies, some of local origin, 
some introduced from Assam and elsewhere, are now 
attacking tea in many parts of the Island, and it be- 
hove') all interested in the cultivation to be upon the 
watch to recognize the signs of disease as soon as pos- 
sible after they appear and to at once attack and as far 
as practicable eradicate the disease. The diseases are 
here, and all experience of cultivators in all ages and 
lands shows that such disease come to stay ; they can- 
not be completely eradicated, but they can be kept in 
check if taken in time. Of course this involves a 
certain expenditure, but if the disease be early 
recognized and properly attacked this need not be 
large. Planters should make it a regular part of 
their work to learn to recognize the diseases and 
to teach this knowledge to conductors, kanganies, 
^nd coolies, and should remember that one dis- 
eased estate may reinfect all its neighbours in a few 
days, if there be any wind, and thus cause them much 
loss or trouble. 
The two chief fungus blights that are attacking tea 
in Ceylon are the Gray Blight, well-known in Assam, 
and a blight which has so far only been noticed in 
Ceylon, and which I have called the Brown Blight. 
Both are now to be found in most of the districts, but 
the latter is the more common of the two. It is not 
always easy to distinguish without the aid of the micro- 
scope which of the two diseases is present in an 
affected leaf, but this is of less practical importance, as 
the effects of the two are the same, and also the 
methods to be adopted for their treatment. Several 
other fungi hava been observed attacking tea, and care- 
ful watch should be given in case of any spread of 
these. When a disease is observed to be spreading, no 
time should be lost in dealing with it. 
Gray Blight. — This disease is due to the attack 
of a parasitic fungus, known to science as Pes- 
talozzia Guepini. It attacks tea in Assam, from 
which country it has very probably been imported 
with tea seed. It also occurs on camellias in India 
and Europe and on citrus (orange and lime 
genus) in America, as well as on other plants in 
various countries, 
It is purely a leaf disease. It is found chiefly, if not 
only, on mature leaves, and does not affect the flush 
by direct attack, but reduces it by injuring the older 
leaves, on whose proper performance of their duties 
the rate of flushing largely depends. If many of 
the old leaves are attacked by the disease, the 
amount of flush may fall to less than half wliat it 
was before the attack. 
The first thing to look out for is leaves showing 
dead portions. If part of a leaf is dead and shows 
a gray or brown colour, the probability is that it has 
been attacked by one or other of the blights we are 
now considering. Of course we know that drip of 
water on the leaf will produce this result, and it may 
also follow from the attack of insect?, and sometimes 
from other causes. If the appearance results from 
any other cause than the attack of an insect or fungus 
blight, it is of little or no importance, is not in- 
fectious, and will not spread, and consequently the 
removal of the few leaves that may come under this 
category need cost little in time or trouble. The 
blights are foes of a different order-, and spread so 
quickly, when once started on an estate that they 
should be at once attacked. Therefore, bearing in mind 
that the blights in question are present to some extent 
in nearly all the districts, it will be good policy for 
planters to make a point of getting all injured leaves 
plucked and destroyed, as explained below. 
In the case of the gray blight, the injured portion 
of the leaf usually turns of a light gray colour, which 
is fairly characteristic of the disease. The edge 
of the injured part where it joins the green 
part of the leaf is usually dark brown, and 
the edge of the yet living part where it meets the 
dead portion is yellowish when held up to the light 
owing to the destruction of the green-colouring matter 
which is going on under the attacks of the fungus, 
which spreads from the dying portions into the living. 
When the fungus starts from one spore only upon the 
leaf, the disease appears as a small gray spot, which 
widens rapidly, but remains approximately circular, 
except where its growth is interfered with by the veins 
or edge of the leaf. Most commonly, however, the 
fungus spreads from several places at once and forms 
an irregular patch, which may at length occupy almost 
the whole leaf. The patch is, however, usually bor- 
dered by a dark line, behind which, in the dead por- 
tion, may often be seen other faint lines concentric 
with it. These when present are very characteristic 
of the attacks of blights. As the attacked part of the 
leaf dies, it turns grayish or whitish in colour on the 
surface. On the dying portion the spores or reproduc- 
tive organs of the fungus are prcrduced in vast numbers. 
Millions may be formed on one leaf, and each one may, 
if it reach the surface of another leaf, cause an attack 
of blight there. The spores are extremely small 
and light, • and consequently float in the 
air like tine dust, and may be carried a long way by 
wind, especially in dry weather. One estate may 
thus easily infect others to leeward of it, though the 
wind belts, now so general, will tend to largely check 
this. When a spore reaches the damp surface of 
another leaf, it promptly germinates and a few days a 
patch of disease appear on the leaf and new spores 
begin to form. 
Bkown Blight.— This is also due to the attack as a 
parasitic fungus, which appears to be new to science, 
and has been named by Mr. G. Massee, of Kew, 
Colletofrichum Camellia. To the eye it closely 
resembles the gray blight : the chief distinction is 
that the attacked portions of the leaf turn to a 
reddish or chocolate brown colour as they die. 
The edge of the diseased part is, as in the 
case of gray blight, bounded by a dark line, 
and the adjacent edge of the green part of the 
leaf, into which the fungus is growing, shows a 
yellowish colour when held up to the light. The spores 
are chiefly formed on the under side of the leaf, and 
appear near the edge of the diseased portion as little 
reddish eruptions, about the size of a very small piu'a 
head. In all other respects the appearance of leaves 
attacked by brown blight is practically much like 
that of those suffering from gray blight. 
Other Blights.— Several other fungus blights may 
at times be found attacking the leaves of the tea 
plant, but the result is always much like that caused 
by the gray and brown blights— a more or less irre- 
gular diseased portion, the centre of which is dead 
and at the edge of the dark part an extension of the 
fungus into the still living portion of the leaf, which 
shows a yellowish colour where first attacked. One 
very common blight, found in all parts of the island, 
is the " Spot Blight," the affected leaves being covered 
with small, roundish gray syots, rarely as large as a 
10-cent piece. This blight does less harm than gray 
and brown blights, but is troublesome enough, and is 
worth keeping down by the same methods as will be 
used for the others. 
Genkkal Peinciples of Tkeatment. — When the 
disease has been recognized on leaves that have been 
largely damaged by it, a close study should be made 
