Phylloxera-resistant Stocks.

New Zealand Journal of Agriculture, Volume 58, Issue 3, 20 March 1939, Page 267

Phylloxera-resistant Stocks.

( Continued from February issue.)

Viticulture.

r I <HE stocks available from the Te THE stocks available belong, Kauwhata State Vineyard belong, with few exceptions, to the Americo-American hybrids and to the Americo-Vinefera hybrids. The former were produced from pure American species and their varieties, and the latter have American and European blood in their composition. Americans. The Riparia x Rupestris combine the characters of the Riparia and ■ the Rupestris, and are represented in New Zealand by the Riparia x Rupestris No. 101-14, produced by Millardet and de Grasset, Riparia x Rupestris 3306 of Couderc, and Riparia x Rupestris 3309 of Couderc. The Riparia x Rupestris 101-14 stock resembles the Rip aria in root system and foliage rather than the Rupestris. It is more tolerant to lime than either. It makes a good growth in most soils, even in the compact clays known as gum lands in North Auckland, and is generally preferred to the Riparia Gloire for planting in Riparia (alluvial) soils. Its affinity for Vinefera is in most cases good. Vines grafted on it produce good crops which ripen early. It is particularly suitable for vines like the Gamays, which are liable to perish through overcropping.

The principal characteristics are : Trunk, thick; habit of growth, semierect ; bark, thick, and greyish in colour ; rods, - long, straight, cylindrical, slightly striped, reddish-chestnut when matured ; shoots (in a herbaceous state), bright red and smooth; leaves at tip of shoot, pale green ; leaves, larger than long, entire, the lateral lobes indicated by larger and more, pointed teeth, the terminal lobe is prolonged by a very pointed tooth ; petiolar sinus, deep V form, nearly closed ; upper side of leaf dark shining green, lower a lighter green, smooth or with a few hairs on the principal nerves ; stalk, short, strong, canaliculated, covered with short brushlike hairs. Unlike the 3306 and 3309, which are male vines, the 101-14 produces small bunches of small dark, violet-black berries. ‘The 101-14 is highly resistant' to phylloxera. The aria x Rupestris 3306 (Couderc) stock is becoming one of the most popular in New Zealand for grafting on both outdoor and underglass varieties of vines because of its very good affinity for Vine) er as, in which it promotes abundant fructification and early ripening. Cuttings of this stock root freely, and grafts take fairly well (30 per cent, to 40 per cent.). On the stiff clay of Te Kauwhata the 3306 makes a vigorous stock, and with the Berlandieri 420. A—on a little better soil— proved to be a very suitable

stock for grafting on the Albany Surprise (syn. Pierce). It is also proving a very good stock for the Black Hamburg, Gros Colman, and Muscat of Alexandria grown under glass. The 3306 is generally. recommended by European authorities for poorer soils than the 101-14 and as being more suitable for clay soils and soils with wet subsoils than the 3309. In New Zealand it is doing well so far wherever - it has been tried. It has the reputation of being one of the most resistant stocks to root-rot . (pourridie), and it resists chlorosis in soils containing up to 30 per cent, of lime. Its principal characteristics are : roots, rather fine, of spreading habit, yellowish in colour ; shoots, long and thin, covered with small hairs (which distinguishes the 3306 from the 3309, which has smooth wood). The leaf, which is a little longer than wide, is also pubescent, that of the 3309 being smooth. The leaf of the 3306 is more Riparia and less Rupestris than the 3309. It is dark green with rosy nerves and sharp narrow teeth. The petiolar is V-shaped, and the sinus is not so open as that of the 3309. The 3306, like the 3309, is a male vine, and in consequence does not bear fruit. (To be continued.)

—J. C. Woodfin,

Vine and Wine

Instructor, Te Kauwhata.