Phylloxera: Wikis

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Phylloxera
Scientific classification
Kingdom: Animalia
Phylum: Arthropoda
Class: Insecta
Order: Hemiptera
Suborder: Sternorrhyncha (was Homoptera)
Superfamily: Phylloxeroidea
Family: Phylloxeridae
Genus: Viteus
Species: vitifoliae
Binomial name
Viteus vitifoliae Fitch 1855
The phylloxera, a true gourmet, finds out the best vineyards and attaches itself to the best wines
Cartoon from Punch, 6 Sep. 1890)

Grape phylloxera (Viteus vitifoliae Fitch (1855) , family Phylloxeridae); originally described in France as Phylloxera vastatrix; equated to the previously described Daktulosphaira vitifoliae, Phylloxera vitifoliae; commonly just called phylloxera (from Greek φύλλο, leaf, and ξερό, dry) is a pest of commercial grapevines worldwide, originally native to eastern North America. These almost microscopic, pale yellow sap-sucking insects, related to aphids, feed on the roots and leaves of grapevines depending on the phylloxera genetic strain. On Vitis vinifera L., the resulting deformations on roots ("nodosities" and "tuberosities") and secondary fungal infections can girdle roots, gradually cutting off the flow of nutrients and water to the vine. Nymphs also form protective galls on the undersides of grapevine leaves of some Vitis species and overwinter under the bark or on the vine roots; these leaf galls are typically only found on leaves of American vines.

Contents

Biology of Phylloxera

The phylloxera louse has a complex life-cycle of up to eighteen-stages that is divisible into four principal forms: sexual form, leaf form, root form, and winged form.

The sexual form begins with male and female eggs laid on the underside of young grape leaves. The male and female at this stage lack a digestive system, and once hatched, they mate and then die. Before the female dies, she lays one winter egg in the bark of the vine's trunk. This egg develops into the leaf form. This nymph, the fundatrix (stem mother), climbs onto a leaf and lays eggs (via parthenogenesis) into a leaf gall she creates by injecting saliva into the leaf. The nymphs that hatch from these eggs may move to other leaves, or move to the roots where they begin new infections in the root form. In this form they perforate the root to find nourishment, infecting the root with a poisonous secretion that prevents it from healing. It is this poison which eventually kills the vine. This nymph reproduces four to seven more generations of eggs (which are also capable of parthenogenetic reproduction) each summer. These offspring spread out to other roots of the vine, or to the roots of other vines through cracks in the soil. The generation of nymphs that hatch in the autumn hibernate in the roots and emerge the following spring when the sap begins to rise. In humid areas, the nymphs develop into the winged form (otherwise, they perform the same role without wings). These nymphs start the cycle over again by either remaining on the vine to lay male and female eggs on the bottom side of young grape leaves, or flying to an uninfected vine to do the same.

Many attempts have been made to interrupt this life cycle to eradicate phylloxera, but the louse has proven to be extremely adaptable, as no one stage of the life cycle is solely dependent upon another for the propagation of the species.

Fighting the "phylloxera plague"

In the late 19th century the phylloxera epidemic destroyed most of the vineyards for wine grapes in Europe, most notably in France. Phylloxera was introduced to Europe when avid botanists in Victorian England collected specimens of American vines in the 1850s. Because phylloxera is native to North America, the native grape species there are at least partially resistant. By contrast, the European wine grape Vitis vinifera is very susceptible to the insect. The epidemic devastated vineyards in Britain and then moved to the mainland, destroying most of the European wine growing industry. In 1863, the first vines began to deteriorate inexplicably in the southern Rhône region of France. The problem spread rapidly across the continent. In France alone, total wine production fell from 84.5 million hectolitres in 1875 to only 23.4 million hectolitres in 1889.[1] Some estimates hold that between two-thirds and nine-tenths of all European vineyards were destroyed.

In France, one of the desperate measures of grape growers was to bury a live toad under each vine to draw out the "poison".[1] Areas with soils composed principally of sand or schist were spared, and the spread was slowed in dry climates, but gradually the aphid spread across the continent. A significant amount of research was devoted to finding a solution to the phylloxera problem, and two major solutions gradually emerged: grafting cuttings onto resistant rootstocks and hybridization.

Use of a resistant, or tolerant, rootstock, developed by Charles Valentine Riley in collaboration with J. E. Planchon and promoted by T. V. Munson, involved grafting a Vitis vinifera scion onto the roots of a resistant Vitis aestivalis or other American native species. This is the preferred method today, because the rootstock does not interfere with the development of the wine grapes, and it furthermore allows the customization of the rootstock to soil and weather conditions, as well as desired vigor. Unfortunately not all rootstocks are equally resistant. Between the 1960s and the 1980s in California, many growers used a rootstock called AxR1. Even though it had already failed in many parts of the world by the early twentieth century, it was thought to be resistant by growers in California. Although phylloxera initially did not feed heavily on AxR1 roots, within twenty years, mutation and selective pressures within the phylloxera population began to overcome this rootstock, resulting in the eventual failure of most vineyards planted on AxR1. The replanting of afflicted vineyards continues today. Many have suggested that this failure was predictable, as one parent of AxR1 is in fact a susceptible V. vinifera cultivar. But the transmission of phylloxera tolerance is more complex, as is demonstrated by the continued success of 41B, an F1 hybrid of Vitis berlandieri and Vitis vinifera. The full story of the planting of AxR1 in California, its recommendation, the warnings, financial consequences, and subsequent recriminations remains to be told. Modern phylloxera infestation also occurs when wineries are in need of fruit immediately, and choose to plant ungrafted vines rather than wait for grafted vines to be available.

The use of resistant American rootstock to guard against phylloxera also brought about a debate that remains unsettled to this day: whether self-rooted vines produce better wine than those that are grafted. Of course, the argument is essentially irrelevant wherever phylloxera exists. Had American rootstock not been available and used, there would be no V. vinifera wine industry in Europe or most places other than Chile, Washington State, and most of Australia. Cyprus avoided the phylloxera plague, and thus its wine stock has not been grafted for phylloxera resistant purposes.

By the end of the 19th Century, hybridization became a popular avenue of research for stopping the phylloxera louse. Hybridization is the breeding of Vitis vinifera with resistant species. Most native American grapes are naturally phylloxera resistant (Vitis aestivalis, rupestris, and riparia are particularly so, while Vitis labrusca has a somewhat weak resistance to it) but have aromas that are off-putting to palates accustomed to European grapes. The intent of the cross was to generate a hybrid vine that was resistant to phylloxera but produced wine that did not taste like the American grape. Ironically, the hybrids tend not to be especially resistant to phylloxera, although they are much more hardy with respect to climate and other vine diseases. The new hybrid varieties have never gained the popularity of the traditional ones. In the EU they are generally banned or at least strongly discouraged from use in quality wine, although they are still in widespread use in much of North America, such as Missouri, Ontario, and upstate New York, where they yield commercially acceptable wines.

The only European grape that is natively resistant to phylloxera is the Assyrtiko grape which grows on the volcanic island of Santorini, Greece, although it is not clear whether the resistance is due to the rootstock itself or the volcanic ash on which it grows.

To escape the threat of phylloxera, wines have been produced since 1979 on the sandy beaches of Provence’s Bouches-du-Rhône, which extends from the Gard Coast to the waterfront village of Saintes Maries de la Mer. The sand, sun and wind in this area has been a major deterrent to phylloxera. The wine produced here is called "Vins des Sables" or "wine of the sand".[2]

See also

References

  • Boubals, Denis, "Sur les attaques de Phylloxera des racines dans le monde", Progres Agricole et Viticole, Montpellier, 110:416-421, 1993.
  • Campbell, Christy, "The Botanist and the Vintner: How Wine Was Saved for the World", Algonquin Books, 2005.
  • Ordish, George, "The Great Wine Blight", Pan Macmillan, 1987.
  • Powell, Kevin, "Grape phylloxera: An Overview". In Root feeders An Ecosystem perspective (Eds S.N. Johnson & P.J. Murray) CAB International 2008.
Footnotes
  1. ^ a b winepros.com.au The Oxford Companion to Wine. "phylloxera". http://www.winepros.com.au/jsp/cda/reference/oxford_entry.jsp?entry_id=2410. 
  2. ^ "Wines of the Sand". Feature Article. Novus Vinum. 2006-09-17. http://www.novusvinum.com/features/vins_des_sables.html. Retrieved 2008-11-05. 

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1911 encyclopedia

Up to date as of January 14, 2010

From LoveToKnow 1911

PHYLLOXERA (Gr. c, yov, leaf, and rjpos, dry), a genus of insects belonging to the family of Aphidae, or Plant-lice, in the Homopterous section of the order Hemiptera. It is chiefly known from the causal relation of one of its species of the most serious of vine-diseases. The name was first given in 1834 to a plant-louse which was observed to "dry up the leaves" of oaks in Provence. About twenty-seven species are now known, all characterized by length not excee 4 ding 06 of an inch, flat wings, three articulations in the antennae, one or two articulations in the tarses, with digitules, but without cornicles on the abdomen.

The following full description of the only species which attacks the vine, the Phylloxera vastatrix, or grape-louse, is reprinted from the article Vine in the 9th edition of this encyclopaedia.

" The symptoms of the disease, by means of which an infected spot may be readily recognized, are as follows: The vines are stunted and bear few leaves, and those small ones. When the disease reaches an advanced stage the leaves are discoloured, yellow or reddish, with their edges turned back, and withered. The grapes are arrested in their growth and their skin is wrinkled. If the roots are examined numerous fusiform swellings are found upon the smaller rootlets. These are at first yellowish in colour and fleshy; but as they grow older they become rotten and assume a brown or black colour. If the roots on which these swellings occur be examined with a lens, a number of minute insects of a yellowish-brown colour are observed; these are the root-forms (radi- ?, cola) of Phylloxera (fig. I); they are about 8 mm. long, of an oval outline and with a swollen body. No distinction between head, thorax and abdomen can be observed. The head bears small red eyes and a pair of three-jointed antenn ae, the first two joints being short and thick, the third more elongated, with the end cut off obliquely and FIG. I. - Root-inhabiting Form slightly hollowed out. Under- (Radicola) of Phylloxera, with proneath, between the legs, lies the boscis inserted into tissue of root rostrum, which reaches back to of vine. the abdomen. The insect is fixed by this rostrum, which is inserted into the root of the vine for the purpose of sucking the sap. The abdomen consists of seven segments, and these as well as the anterior segments bear four rows of small tubercles on their dorsal surface. These root-dwelling insects are females, which lay parthenogenetic eggs. The insect is fixed by its proboscis, but moves its abdomen about and lays thirty to forty yellow eggs in small clusters. After the lapse of six, eight or twelve days, according to the temperature, the larvae hatch out of the eggs. These are light yellow in colour and in appearance resemble their mother, but with relatively larger appendages. They move actively about for a few days and then, having selected a convenient place on the young roots, insert their proboscis and become stationary. They moult five times, becoming with each change of skin darker in colour; in about three weeks they become adult and capable of laying parthenogenetic eggs. In this way the insect increases with appalling rapidity: it has been calculated that a single mother which dies after laying her eggs in March would have over 25,000,000 descendants by October. If, however, the insect were content with this method of reproduction the disease could be isolated by surrounding the infected patches with a deep ditch full of some such substance as coal-tar, which would prevent the insects spreading on to the roots of healthy vines. The fertility of the parthenogenetically produced insects would also diminish after a certain number of generations had been produced.

As the summer wears on a second form of insect appears amongst the root-dwellers, though hatched from the same eggs as the form described above. These are the nymphs, destined to acquire wings; their body is more slender in outline, and at first they bear well-marked tubercles. After several moults the rudiments of two pairs of wings appear, and then the insect creeps up to the surface of the earth, and on to the vine. Here it undergoes its fifth and last moult, and appears as a winged female, capable of reproducing parthenogenetically. The winged form has a slender body with distinct head (fig. 2). The eyes are well developed, with numerous facets; the antennae minal one shaped like that of the are transparent, with few nervures, flight. The anterior pair reach far beyond the end of the abdomen; the posterior are narrower and not so long. These winged forms are about i mm. long. They fly about from July till October, living upon the sap of the vine, which is sucked up by the rostrum from the leaves or buds. They lay their parthenogenetically produced eggs in the angles of the veins of the leaves, in the buds, or, if the season is already far advanced, in the bark. In very damp or cold weather the insect remains in the ground near the surface, and deposits its eggs there. The eggs are very few in number and of two sizes, small and large (fig. 3, b and c). From the larger a female (fig. 4) is hatched in eight or ten days, and simultaneously, for the first time in the life-history of the Phylloxera, a male (fig. 3) appears from the smaller egg. Neither male nor female has wings; the rostrum is replaced by a functionless tubercle; and there is no alimentary canal. The female is larger than the male and differs from it and the other forms in the last joint of the antennae. The life of these sexual forms lasts but a few days, and is entirely taken up with reproduction. The female is fertilized by the male and three or four days later lays a single egg - the winter egg - and then dies. This egg is laid inthecrevicesofthebarkof thevine, and as it is protectively coloured it is almost impossible to find it. Here the winter eggs remain undeveloped during the cold months; but in the following spring, as a rule in the month of April, they give from small egg c, laid by winged female (fig. 2); b, large egg; c, small egg.

FIG. 3. - a, Male produced duced from large egg (fig. 3, b), laid by winged female (fig. 2).

FIG. 4. - Wingless Female pro birth to a female insect without wings, which resembles the rootdwelling forms, but has pointed antennae. These forms are termed the stock-mothers; they creep into the buds of the vine, and, as these develop intofthe young leaves, insert their proboscis into the upper side. By this means a gall is produced on the under side of the leaf.

Scheme of the Various Forms of Phylloxera vastatrix. A. Root-infesting forms, Root-infesting forms, znd generation, 2 Winged forms, 1 Root-infesting forms, 3 rd generation, Wingless female. Male.

&c.

Winter egg. Stock-mother.

I I Gall-producing Root-infesting 2 1 ditto A.

Missing image
Phylloxera-1.jpg

The gall is cup-shaped, and its outer surface is crumpled and covered with small warts and hairs. The opening upon the upper surface have three joints, the terroot-dwellers. The wings and are well adapted for FIG. 2. - Phylloxera. Winged Female which lives on leaves and buds of vine, and lays parthogenetically eggs of two kinds, one developing into a wingless female, the other into a male.

Missing image
Phylloxera-2.jpg
Missing image
Phylloxera-3.jpg

of the leaf is protected by similar structures. Within this gall the stock-mother lives and surrounds herself with numerous parthenogenetically produced eggs - sometimes as many as two hundred in a single gall; these eggs give birth after six or eight days to a numerous progeny (gallicola), some of which form new galls and multiply in the leaves, whilst others descend to the roots and become the root-dwelling forms already described. The galls and the gallproducing form are much commoner in America than in the Old World.

The particular species of phylloxera which attacks the vine is a native of the United States, probably originating among the wild vines of the Colorado district. It was first observed in 1856 by Asa Fitch (1809-1878), who did not suspect its mischief, and called it Pemphigus vitifoliae. In 1863 it was independently discovered by Westwood in an English vinery at Hammersmith; he was ignorant of Fitch's observation, and called it Peritymbia vitisana. From 1858 to 1863 there were many importations of American vines for grafting purposes to Bordeaux, Roquemaure and other parts of France, England, Ireland, Germany, Portugal, &c. It is practically certain that the deadly phylloxera was imported on these plants. A year or two later certain vine-growers in the South of France began to complain of the new vine-disease. M. Delorme, of Arles, in 1865, appears to have been the first who recognized its novelty and had a presentiment of disaster. The disease steadily spread outwards in concentric circles from its first place of lodgment near Roquemaure. Within two or three years whole departments were infested. In 1866 a second centre of infection made its appearance near Bordeaux. The vine-growers were at their wits' end to account for this new plague, which threatened to be even more costly than the oidium. The completeness of the ruin which threatened them may be illustrated by the statistics for a single commune, that of Graveson, whose average annual production of wine in the years1865-1867was about 220,000 gallons. In 1868 this fell to 121,000 gallons, in 1869 to 48,400 gallons, in 1870 to 8800 gallons, and by 1873 to 1 ioo gallons.

In 1868 Planchon proved that the disease was due to a new species of phylloxera, which was invariably found on the roots of the affected vines, and to which he accordingly gave the prophetic name of Phylloxera vastatrix. During the next ten years a series of students, of whom only Riley and Balbiani need be mentioned here, worked out the natural history of Phylloxera vastatrix, and proved its identity with the American grape-louse. Its devastations rapidly assumed gigantic proportions. In France, where the disease was by far the most prevalent - owing in great part to the obstinacy with which the vine-growers at first refused to take any reasonable precautions against its spread - M. Lalande, president of the chamber of commerce at Bordeaux, in 1888 calculated the direct loss to the country by the phylloxera at 10 milliards (£400,000,000), or double the indemnity which had been paid to Germany in 1871 1 The phylloxera has made its appearance in almost every vinegrowing country in the world. Thus it appeared in Austria-Hungary in 1868; in Italy, in spite of the frantic efforts made - as in other countries - to keep it out by strict legislation against the import of vines, in 1879; in Russia in 1880; in Germany, on the Rhine and Moselle, and in Switzerland in 1872; in Madeira, Spain and Portugal, about 1876. The pest even crossed the oceans, and appeared in Australia, at Geelong, about 1880; it has since twice broken out in Victoria, and has ravaged the vineyards of South Australia and New South Wales. At the Cape, in spite of a long endeavour to prohibit the import of the phylloxera, it appeared about 1884. In 1885 it crossed the Mediterranean to Algeria. There was only one country where its ravages were long unimportant; that was its home in the United States, where the native vines had become, by the operation of natural selection, immune to its attacks. Yet no imported vine has ever lived there more than five years, and in 1890 the phylloxera crossed the Rocky Mountains, and seriously damaged the vineyards of California, where it had previously been unknown.

Three different methods of fighting the pest have been successfully adopted. One is to kill the phylloxera itself; another, to destroy it along with the infected vines, and plant fresh and healthy plants; the third, to adapt the secular therapeutics of nature, and to introduce American vines which a long acquaintance with the phylloxera has made immune of its ravages. Insecticides, of which the bisulphide of carbon (CS 2) and the sulpho-carbonate of potassium (KS CS2) remain in use, were injected into the earth to kill the phylloxera on the roots of the vine. These methods were chiefly advocated in vineyards of the first class, where it was worth while to spend a good deal of money and labour to preserve the old and famous vines: the Château Leoville Poyferre and Clos Vougeot are instances. Some good judges attribute the peculiar and not unpleasing flavour of certain clarets of 1888 to means thus adopted to kill the phylloxera. The second plan was largely adopted in Switzerland and on the Rhine, where measures resembling those taken with cattle suspected of anthrax were applied to all diseased vineyards. The third plan, which consists in replanting the affected vineyard with American vines - such as the Vitis labrusca, V. riparia, V. rupestris or V. monticola - has proved the most generally successful.

A very good bibliography will be found in Les Insectes de la vigne, by Professor Majet of Montpellier (1890), which is the best book on the subject. Reference may also be made to the classic memoirs of Planchon, culminating. in Les Mceurs de la phylloxera de la vigne (1877); Dreyfus, Uber Phylloxerinen (1889); Lichtenstein, Histoire du phylloxera; the Rapports annuels a la commission superieure du phylloxera; and the excellent Report on Phylloxera drawn up by the Hon. J. W. Taverner (Victoria, 1899, No. 68).

(W. E. G. F.)


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