Practical advice for choosing rootstocks. Introduction

Transcription

1 Practical advice for choosing rootstocks Introduction

2 .the use of rootstocks, quite apart from saving the European (and North American, South African and New Zealand) wine industry from oblivion, offers real scope for improvement in wine quality at all levels. In other words these are tools to be used. If used skilfully and intelligently they help make better wine; used clumsily and without sufficient thought, they will make rubbish. James Halliday and Hugh Johnson (1992) The Art and Science of Wine. Octupus Publishing.

3 Rootstock use in the Mornington Penninsula Current rootstock use? Inhibitors to rootstock use?

4 Pathway to successful rootstock use: Rootstock Characteristics Create a balanced vine Site Factors Final Decision Rootstock Management

5 Phylloxera: Biology Fil-ox-era ( dry leaf ) Yellow, aphid-like insect 1mm long X 0.5mm wide Native to North America Can only live on grapevines

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8 Phylloxera: Biology Lives mainly on vine roots.. but Moves into canopy Causes galls to form on the roots leaf galls can also form, but only on rootstocks

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11 Biology Kills vines: Hijacks vine hormone system Wounds cause fungal rot Phylloxera are all female & breed asexually Only one insect needed to start an infestation 200 eggs per female Up to 15 generations 16 billion in 12 months Active Nov-April when soil temps rise

12 Symptoms Above Ground yellow leaves stunted shoots vine decline weak growth reduced yields vine death

13 Infested vineyard, note dying vines centre rows

14 History of phylloxera and rootstocks Phylloxera imported into Rhone Valley Widespread damage in Rhone valley First symptoms in Bordeaux Phylloxera identified as the cause Early 1870 s- Experimentation on methods of control: flooding, fumigating, whale oil and petrol, crushed bone and sulphuric acid, cows urine(!), beating the ground

15 History of phylloxera and rootstocks 1872 (approx.) - First V. vinifera grafted onto American vitis sp La Rhizoplastie.guide on field grafting produced Phylloxera first identified in Australia (Geelong) 1878 S.A. parliament passes act preventing importation of planting material practically all vineyard regions in France infested -370,000 ha destroyed (Galet, 1979)

16 History of phylloxera and rootstocks Montpellier school of agriculture set up a grafting course Phylloxera recorded in all major grapegrowing countries of Europe 1885 Chemical control failing- vines dying French government backed grafting, rootstock breeding programs begin Phylloxera recorded in Champagne, California, New Zealand and South Africa

17 History of phylloxera and rootstocks just under 1 million hectares grafted to rootstocks in France 1900 onwards- Europe one big rootstock experiment 1900 onwards- Phylloxera continues to spread around the globe

18 Further reading: Phylloxera by Christy Campbell The great wine blight by George Ordish

19 Vitis Species American species co-evolved with phylloxera and so developed resistance mechanisms There are over 40 vitis species, mainly found in North America Four American vitis species are commonly used for rootstock breeding: V. riparia V. rupestris V. berlandieri V champinii Each American species evolved in geographically distinct areas of North America

20 Vitis Species The American species were cross bred with the aim of maximising the desirable traits and minimising the undesirable traits The successful crosses are the rootstocks that we use today These rootstocks have characteristics that reflect those of their parents

21 Vitis Species Understanding the basic characteristics of the four parents used in breeding will give an insight into the expected performance of a rootstock at a particular site and will therefore aid in the selection process The following information on the characteristics of the Vitis species used for rootstock breeding is taken from Cirami, (1999) unless otherwise specified.

22 V. riparia (the river grape) V. riparia is a trailing or climbing vine (Furkliev, unpublished). Of all the American Vitis species it has the greatest geographical range. It extends from the centre of Canada in the north, to Texas and Louisiana in the south and west to the Rocky mountains.

23 V. riparia: Distribution Image:

24 V. riparia V. riparia prefers cool, moist environments where there is an uninterrupted supply of water. In its natural environment it grows along the edges of rivers and streams or in shady, moist forests.

25 V. riparia Image:

26 V. riparia Copyright University of Wisconsin System Board of Regents. This digital version of the Virginia Kline Collection: Ecological Communities of Wisconsin is published by the Libraries of the University of Wisconsin-Madison.

27 V. riparia Its root tends to grow laterally rather than vertically (Furkliev, unpublished). It has a short vegetative cycle adapted to low light, conditions Resistance to the cold Has some tolerance of wet feet It is susceptible to drought conditions and performs poorly in sandy or calcareous soils. Very high phylloxera resistance Cuttings of Vitis riparia root very easily and graft well.

28 V. rupestris: the rock grape This species occurs commonly in stony soils in south-western Texas extending northward and eastward to New Mexico, Indiana, Tennesee and Pennsylvania. V. rupestris prefers deep, gravelly, rocky soils next to mountain streams.

29 V. rupestris Image:

30 V. rupestris Image: Scott Bauer, USDA Agricultural Research Service, United States humb.cfm?sub=16779&start=1

31 V. rupestris Reproduced with permission of Dr A. Walker (UC Davis)

32 V. rupestris Reproduced with permission of Dr A. Walker (UC Davis)

33 V. rupestris It produces a deep root system It requires a deep soil and penetrable subsoil. It has moderate lime tolerance (less than V. berlandieri and more than V. riparia) A long vegetative cycle. Roots and grafts easily for nursery production but is sensitive to root-rotting fungi.

34 V. berlandieri A native of the limestone hills of southwest Texas, this species is found in New Mexico and north Mexico, It thrives in calcareous, non-fertile soils and dry, hot climates..

35 V. berlandieri Image:

36 Vitis berlandieri Reproduced with permission of Dr A. Walker (UC Davis)

37 South-West Texas V. berlandieri Image: Julie Wyatt at

38 V. berlandieri Lime tolerant Drought tolerant Salt tolerant Long vegetative cycle V. berlandieri is highly resistant to phylloxera Excellent source of rootstock material but only as hybrids with other vitis species as they are difficult to root from cuttings

39 V. champinii Considered to be a natural hybrid between V. rupestris and V. mustangensis (V. candicans) Found in south-central Texas Prefers well-drained calcareous soils Ramsey

40 Vitis champinii Reproduced with permission of Dr A. Walker (UC Davis)

41 Summary American vitis species are the parents of the rootstock hybrids we use They evolved in diff. geographical areas and have different attributes which is therefore the reason why we have rootstock hybrids with a wide range of attributes Understanding the conditions under which these Vitis species evolved gives us an insight into which rootstocks are best suited at a own site