1845; in 1848 it appeared at Versailles; by 1851 it had spread

through all the wine-producing countries of Europe, being specially virulent in the lands bordering on the Mediterranean; and in the following year it made its appearance in Madeira. Like the Phylloxera {g.v .; also Wine), the mildew is in its origin probably American. The disease is characterized by the appearance of a mycelium forming white or greyish-white patches on the young leaves; this spreads quickly and attacks the older leaves and branches, and ultimately reaches the grapes. At first these are marked only by small brown spots; but the spots spread and fuse together, the skin of the grape is destroyed, and the flesh decays, the seed only remaining apparently untouched. The disease spreads by the mycelium growing over the epidermis of the plant. The hyphae composing the mycelium are provided with haustoria which project into the cells of the affected part (fig. 3). Some of "i the hyphae which project from the leaf bear spores (conidia), which are constricted off one

at a time, and by their means

the fungus

is

distributed

(fig. 2, 3). The perithecia are only produced exceptionally

in Europe, but this stage of

the life-history is common in

the United States and causes

a widely spread disease among

the American vines.

The

mildew is in its turn attacked

by a fungus of the same tribe,

Cicinnobohts Cesalii,

which

lives parasitically within the

hyphae of its liost, and at

times even succeeds in destroying it. The means which

have proved most efficacious,

both as a remedy and a preventive of this disease, is to

scatter flowers of sulphur over the vines, before the morning

dew has evaporated.

An-

other method is to boil one

part of lime with three parts

//

B

-Vncinula mcalor (Erysiphe

Tuckeri). A and B, mycelium (m), °f

^"1?^"^.

and to spnnkle

with haustoria (A). (Afterde Bary.) »>?<= ">^ture over the affected 1".^^!^/^"°^"'^*'"'"'^ Another fungus which atare mdicated.

^^^^^ ^;^^^ especially those of America, is Plasmopara viticola, which has also been mtroduced from America to Europe. The mycelium spreads through the green parts of the plant, attacking the leaves, twigs and unripe grapes. On the upper side of the leaf, where it is first visible, it forms pale green irregular spots, which become darker in colour. On the under side of the leaf these patches are white and are composed of the spore-bearing hyphae. The leaf ultimately becomes dried up and brittle. The grapes

which are attacked cease to grow, turn brown or white, and ultimately dry up and fall off.

This disease has been successfully treated with a spray of copper sulphate and lime, or sulphate of iron; solutions of these salts prevent the conidia from germinating. Anthracnose is the name usually given to a disease which was formerly known as " charbon, "

" pech " or " brenner."

This

disease is caused by the parasitism of Sphacelotna ampelinum, one of the Pyrenomycetous fungi (fig. 4). The fungus assails all the green parts of the vine, and injures the leaves and young shoots as much as it does the grape itself. The first sign of its presence is the appearance of a minute spot, which is greyish in the centre, with a brown border.

This spot increases in size; in the stalks it assumes an oval shape, with its long axis parallel to the stalk, whilst in the leaves and grapes it is more or less circular in outline.

The centre of the spots on the grapes becomes darker as the disease advances, and a red line appears dividing the dark brown border into an outer and an inner rim and giving a very characteristic appearance to the diseased plant. The surrounding tissue enlarges, so that the spots appear as if sunk in depressions, and bear a considerable resemblance to hailstone wounds. Later the spots on the leaves often drop out. The berries do not shrivel up as those do that are affected by the black rot. The mycelium of Sphaceloina grows just beneath the cuticle of the vine, through which it soon bursts, giving rise to a number of minute hyphae, which bear conidia. These are minute, oval, colourless spores, which serve to spread the disease over the vineyard and from place to place. The complete life-history of this form is at present unknown; and information as to where the f^ungus passes the winter, and m what form, would probably afford some useful indications as to the method that should be adopted to combat the disease. Anthracnose has been

known in Europe for many years, but has only been observed in America since 1 881, whither it was probably imported from the old world. As a preventive to its attacks the copper sulphate sprays and a solution (50 %) of iron sulphate have been found very useful, as well as care in planting on well-djained soil that does not lie too low, the disease seldom appearing in dry, well-exposed vineyards. A great deal of confusion still exists with regard to this disease. A similar disease which of late has frequently been found in England, and which is ascribed to the fungus Gloeosporium ampelophagum, is very similar to it. In their mode of attack,

in the symptoms they produce, and in the result upon the grapes and the vine the two fungi are so much alike that for practical purposes they may be regarded as identical. Massee recommends

that the shoots should be dredged with flowers of sulphur at intervals of ten days, while the disease continues to spread, a small quantity of quicklime in a finely powdered con-FiG. 4 . — Charbon or

Anthracnoseof Vine,

caused by Sphaceloma

ampelinum.

1. Portion of twig with

discoloured patches,

caused by the fungus.

2. Fruit attacked by

the f ungus(reduced).

Fig. 5. — Black Rot of Grapes,

Cuignardia Bidwellii.

1. Grapes attacked by the fungus; the fruit becomes black,

hard and shrivelled.

2. Fructification of the fungus, entire and in section; the latter shows the asci containing as cos pores, much enlarged.

3. Single ascus, more enlarged, showing the eight contained

spores.

dition being added and the quantity of lime being increased at every application, not so as to exceed the sulphur, however. The iron sulphate solution should be used while the vines are in a dormant condition, and diseased parts should be cleared away and burned.

The black rot, like the Uncinula and Plasmopara, is also American in its origin. It has been known and observed there since 1848, but appeared

for the first time in France in 1885. The disease is caused by a fungus, Cuignardia Bidwellii (fig. 5) {Phoma uvicola), one of the Pyrenomycetes, and by some authorities it has been considered to be a further stage in the life-history of Sphaceloma ampelinum. The fungus is most conspicuous on the grapes, but the leaves and stems From Hartig's Lchrbuch dcr PJlanzenireitkheilen, by pemiission of Julius Sprinser.

Fig. 6.

—

Rosellinia (Dematophora) nualrix. A. Mycelium of the fungus attacking root of vine (reduced). B. Portion of vine root, showing masses of fructification (perilliecia) of the fungus (reduced).

are also affected. The grapes are not assailed until nearly fuU-gro^vn, when a brownish spot appears, which spreads over the