April 1, 1902.] THE TROPICAL AGRrCXJLTURIST. 
655 
oolonr of the nfused leaf of black tea. although 
treated in exactly the same manner, with the ex- 
ception of the preliminary heating to a temparature of 
boiling water. , ^, , . 
Thii would indicate that the presence of the active 
enzyme was necessary for the proper oxidation of 
the constituents of the sap or leaf to produce the 
colour of black tea. 
From the higher percentage of unchanged tannm 
in green tea it wor.ld appear that the enzyme has a 
considerable influence on this product. 
Another point is in connection with the mrjour. It 
there is »ny flavour in green tea it cannot be due 
to the action of the enzyme during manufacture, 
as this ig completely destroyed in the preliminary 
process of steaming. Some planters state that tho 
up-country green teas have no more flavour than the 
low-country teas of the same class, and if this is 
correct, it would appear that the enzyme has some 
effect in producing flavour, as its destruction has 
apparently prevented the development of the flavour 
' that we know is characteristic of the black teas 
from up-country leaf. If it is a fact that leaf from 
an np-oountry estate has less flavour when manii- 
faotnred into green instead of black tea, the dimi- 
nution of flavour might be due to the destruction 
of the enzyme, or. as ia more likely, to the loss ot 
essential oil during the steaming process. 
In the investigation which we are continuing, there 
are several points of interest which m^-y be men- 
tioned here. The most important is that of deter- 
mining the nature of the reactions ami the products, 
when the several constituents of the leaf are brought 
into contact with the pure enzyme at different tem- 
• paraturea. This ia, of course, first being carried out 
in the laboratory, and if possible and deemed advanta- 
geous, will be applied in the factory. 
The reaction between the enzyme and the tannin, 
essential oil, cellulose and protied, is being deter- 
mined separately for each of these bodies, together 
•with that between the enzyme and tea leaf en masse. 
It is obvious that the products of these reactions 
»re many - nd not always easy to recognize, but it 
we can prove that any of them will impart a desir- 
able flavour to tea, a great point will have been gained, 
though it will remain to be seen whether it can be used 
commercially. , . , , ^ i. , 
The work must be continued in the factory at low 
and high elevations, and this we are prepared to do at 
the earliest opportunity. 

WOODINESS OF THE PASSION FRUIT. 
A. Despeissis. 
A disease hitherto unknown in Western Australia 
was, last season, first observed on some locally grown 
passion vines. That disease has of late years played 
havoc with the passion fruit plantations around 
Sydney, and our ports have this season been made 
the dumping ground of several important consign- 
ments of diseased passion. 
The figures illustrating this woodiness ' show the 
disease in a mild form. 
They are taken from a Paper on the subject, pre- 
pared by Dr. N. A. Cobb, Government Vegetable Patho- 
logist of New South Wales. . ^ 
The disease is still an obscure one. First observed 
around Parraraatta some seven or eight years ago, it 
has since spread to the whole surrounding County 
of Cumberland, where its progress is more or less 
erratic. , , . 
It afiects most vineyards in the locality named, 
and at the same time spares a few in the centre of 
infection. 
Even in a diseased vineyard some plants eseape ; 
the disease is less common on moist, free soil, suited to 
passion fruit, than elsewhere. 
Symptoms. 
A "woody" passions vine is stunted in growth, 
with short distorted canes, of pale-yellowish leaves 
instead of a dark-green colour. The stocks are some- 
times enlarged and knobby ; much of the fruit drops 
early the rest hang on, become distorted, crack on 
the surface, and when cut open are either empty 
and show a considerable thickness of the rind, or 
what there is of tt e edible pulp is thin, has a "flat" 
taste, with a colour diiJerent from that found in 
healthy fruit. The seeds do not ripen properly, and 
remain light and sometimes glassy instead of turning 
black. 
Causes or the Disease. 
A disease passion vine often shows amongst woody 
fruits, some which have every appearance of sound- 
ness, and yet seeds from these apparently sound 
fruit contain in them germs of the disease which, 
when shown, they transmit to the resulting p'ant. 
Exposed situations and frosts are also known to 
have a prejudicial influence on pnssion vines show- 
ing a tendency to woodiness, but, above all, exhaus- 
tion of the soil seems to accompany in most cases the 
woody disease. 
The passion fruit plant is most exacting on the 
store of plant food in the ground. By reason of its 
rank growth and its pvodigious bearing capacity (it 
bears two to three crops of fruit each year) it soon 
exhausts the soil of nourishment as well rs of mois- 
ture. It has been noticed that, where manured, 
the vines are less affected by the disease than 
are vines growing alongside which have been stinted of 
fertilisers. 
Dr. Cobb has observed on the yellow spotted leaves 
of diseased plants, as well as ou the spotted bark 
of dead branches, a specific fungus wiiich he be- 
lieves to be associated with woodiness of the passion 
fruit. 
REMEDIEi, 
The passion vine is a gross feeder. According to 
Mr. F. B. Guthrie's computatiou, each passion vine 
with fruit removes on an average annually from the 
soils ejoz.nitrogen, IJoz. phosphoric acid, and 2^ oz. 
potash, so that a vineyard planted with 300 (12ft, 
M 12ft,) passion vines to the acre would remove: 
nitrogen, 117 lbs, ; phosphoric acid, 28 lbs ; potash, 
52 lbs. 
Knowing that sulphate of ammonia of commerce 
contains about 20 per cent, of nitrogen, superphos- 
phate a-bout 14 per cent, phosphoric acid, and sul- 
phate of potash of commerce 50 per cent, of potash, 
we arrive at the following mixture, in order to 
restore to the land all the elements of plant food 
extracted by pasion vines, and by a crop of passion 
fruit, viz. :— 
Sulphate of Ammonia 600 lb. 
Superphosphate of Lime . . ... 200 ,, 
Sulphate of Potash, 100 ,, 
Such a mixture, applied at the rate of 3 lb., per 
vine, would cost 4cl. per vine or a little over It 
should be applied a year or so after the vines are 
plunted. 
Besides a liberal application of chemical fertilisers, 
it has been suggested that, considering that the woody 
disease is propagated by means of diseased seeds, 
and, moreover, that in all attacked vineyards thero 
are some vines which always look healthy and ap- 
pear to be proof against the blight, cuttings be 
taken from such vines and planted with a view to 
obtaining passion vines endowed with the immunity 
of the parent.— Jowoio/ of the Department of Agricul- 
ture oj Western Australia. 
ALEXANDRIA BANANA DISEASE. 
Peeliminart Eeport Bi' Da. Loos and 
G. P. FOADEN. 
A few daye ago we stated that the report of Dr. Looa 
and Mr. Foaden on the disease, which has caused such 
widespread destruction among the Alexandria bana- 
nas, had appeared and been issued by the iVIunicipality. 
Tl.a disease, according to the report, is caused by • 
worm of the same species as that which caused grMt 
