Kuldeep garwa

Propagation Propagation by Graftingby Grafting

PROPAGATION OF HORTICULTURAL CROPS AND NURSERY MANAGEMENT

SUBMITTED BY ; SUBMITTED TO;

Kuldeep garwa Dr. L.N.Mahawar

GraftingGraftingDefn: connecting 2 pieces of

plant tissue to grow as one plant

It includes the SCION which forms the above ground part of the grafted plant:

AND the ROOTSTOCK which is the lower portion of the grafted plant which provides the root system for the new plant:

GraftingGraftingAn INTERSTOCK or intermediate rootstock may be used with some fruit trees where a degree of incompatibility occurs:

Interstocks are not normally needed with ornamental plants:

Grafting with interstocks is referred to as DOUBLE WORKING

GraftingGraftingThe aim of grafting is to make clean

cuts in the tissue of the two pieces so that the CAMBIUM tissues can be matched together:

Cambium is the main layer of meristematic tissue in woody plants:

It is located as a thin layer of tissue immediately under the bark in stem and roots:

The botanical limits of graftingThe botanical limits of grafting

Grafting within species:

Grafting of species within the same genus:

Grafting of different genera within the same family:

Grafting between families:

Reasons for grafting Reasons for grafting plantsplantsTo propagate

plants which cannot be economically propagated by other techniques

Eg. Cultivars of ornamental shrubs and trees

Reasons for grafting Reasons for grafting plantsplantsTo control the

growth and performance of trees

Eg. Apple and pear orchards

Malling series rootstocks

Malling 27, 26, 9

Reasons for grafting Reasons for grafting plantsplantsTo confer

resistance to pathogens to the grafted plant

Eg. WaxflowersEg. AvocadosEg. GrapesEg. Tomatoes

Reasons for grafting Reasons for grafting plantsplantsTo bring fruiting

plants into fruit production earlier in the life of the plant:

All fruit crops which are commercially grafted:

Fruit at 2-3 years

Reasons for grafting Reasons for grafting plantsplantsGrafting to obtain

special effects in plants:

Eg. Weeping standards

Eg. 2 citrus fruits on the same tree

Eg. Multicoloured rose plants

Reasons for grafting Reasons for grafting plantsplantsGrafting as an

orchard management technique

Eg. Top working of fruit trees to change varieties

Eg. Frame working of fruit trees to assist pollination

Grafting practice with students

Factors of importance in the Factors of importance in the healing of a graft unionhealing of a graft union

Time of yearScion material at

correct stage of growth

Standard of carpentry

Tying of the graftGrowing

environment

Polarity in graftingPolarity in grafting

Correct polar differentiation of stock and scion must be maintained:

The PROXIMAL end of the scion is fitted to the DISTAL end of the stock:

Selection of suitable Selection of suitable rootstocksrootstocksWith woody

ornamentals, most rootstocks used are closely related species to the scion:

Many are seed propagated:

Easy to propagate and fast growing:

The vigour characteristics of the rootstock usually determine the size and vigour of the grafted plant:

This means that many grafted shrubs grow to a large size:

Scion wood Should be One or twoYears old

Tying materials for Tying materials for graftinggraftingWith t-budding, simple rubber budding patches are often used:

The rubber is biodegradable and they will disintegrate within 4-6 weeks:

PVC budding tape is widely used but must be cut off after the graft union has formed:

Tying materials for Tying materials for graftinggraftingAt UQ Gatton we use the medical laboratory tape “PARAFILM”:

This is a thin, stretchable tape which seals the graft union very effectively against the entry of water:

It also degrades rapidly so it does not need to be removed:

METHODS OF GRAFTING

Selection of Scion: Scion stick or bud stick should be healthy

with swollen eye buds and 10 to 15 cm length and of pencil size

thickness. Leaves are defoliated 8 to 10 days before cutting for

grafting.

Procedure

Make a slanting cut up to 5 cm to the bud stick and same length

deep notch to mango rootstock seedling.

Put the cut part of scion in the notch of rootstock and tie with 1

cm wide polythene film tape.

Veneer Grafting

Season: Veneer grafting should be performed in the month of September to

October

After Care

Grafted plants / seedlings are kept humid and moist condition.

Scion shoot starts sprouting in about 3 to 4 weeks.

Polythene strip should be removed after the success of graft.

Grafts ready for planting in 3 months. Success rate is 75 to 80 %.

Veneer Grafting

Stone GraftingStone Grafting

Selection of Scion: Scion sticks with 7 to 8 cm long from current year growth from healthy mother plants should be selected.

Procedure Stone grafting operation should be performed in July- August

months.

Vertical cut of 3 to 4 cm is given on the rootstock and a corresponding wedge shaped cut is given on the scion.

Wedge shaped cut on scion is matched with the cut on rootstock and then tied firmly with a polythene strip.

Stone GraftingStone Grafting

After Care

Remove the growing shoots from root stock and inflorescence from

grafted scion immediately after emergence.

Remove the polythene strip when union is formed and protect the graft

from hot sun, pest and disease attack.

Advantages

Survival Success is more than 80 to 90 %, Requires less time and this

Method is very suitable for coastal region.

5. Grafted Scion 6. Successful Grafts

1. Selection of bud sticks 2. wedge shaped Cut on Scion

3. Vertical Cut on Rootstock

4. Grafting and Polystriping

Inarch GraftingInarch Grafting

Selection of Scion and Rootstock:

Select one year old at least two feet long and healthy rootstock

grown in pots / polythene bags.

Root stock plant and scion stock plant sticks should have equal

thickness. It should be from current year growth and from

healthy mother plant

Season

August-September is best season for Inarch Grafting.

Procedure:Procedure:

Arrange the root stocks and scion tree on some platform or

mandapam and Mark the grafting locations on stock and scion.

Remove 5 cm long, 1 to 2 cm wide & about 0.2 cm deep slice

of bark along with wooden part from stock and scion branches.

Bring the cut surfaces together, cover the joint with a banana

leaf sheath and tie them together with soft threads and cover joint

part with cow dung plaster to protect from rain water.

Inarch Grafting

Water the plants as and when required. Cut the scion from the

parent tree after 2 to 3 months when the wound has healed.

One week after separating the plant from root stock, the part of

the rootstock above the graft is cut off.

Keep the graft in semi shading area to harden the graft before

transplanting into the main field.

After care

Inarch Grafting

Grafting MethodsGrafting Methods Bench grafting

Field methods

Container or field methods

Repair grafting

Bench graftingBench grafting Whip-and-tongue graft Saddle graft

Whip-and-tongue graftingWhip-and-tongue grafting

useful for small (1/4-1/2 in.) material, double working (interstocks), root grafting, and bench grafting

splice grafting (the tongue is not made)

both stock and scion are dormant

Whip and Tongue GraftingWhip and Tongue Grafting

Cut a shallow angle

Whip and Tongue GraftingWhip and Tongue Grafting

Use the pith as center and split the stem. Note finger position!

Look at that finger position again!

Please don’t cut yourself!

Whip and Tongue GraftingWhip and Tongue Grafting

Repeat the same cuts with the scion wood except cut the bottom of the scion.

Whip and Tongue GraftingWhip and Tongue Grafting

Push rootstock and scion together with cambium lined up on one side.

Whip and Tongue GraftingWhip and Tongue Grafting

Whip and Tongue GraftingWhip and Tongue Grafting

Wrap the whole graft and also the tip of scion.

Healed GraftHealed Graft

Figure 1 Figure 2A (top), Figure 2B (bottom)Figure 3A (left), Figure 3B (right)

Saddle graftingSaddle grafting useful for machine grafting, bench

grafting of grape and Rhododendron scion and stock should be the same size grafting is done when stock and scion

are dormant, then the completed graft is stored in a grafting case until the graft union has healed

Field methodsField methods Cleft graft

Wedge graft

Bark graft

Cleft graftingCleft grafting useful for topworking fruit trees, crown-grafting grapes

the best time is early spring, before active growth

wedge grafting allows 1 more scion per stock

Bark graftingBark grafting Two types (rind and inlay-bark

grafts) differ only in prep of stock’s bark, which should be slipping

often used in lieu of cleft graft later in the season

Figure 23 Figure 24Figure 25 Figure 26

Container or field Container or field methodsmethods

Side grafts Approach grafts

Side graftingSide grafting defn: (smaller) scion inserted into

the side of a (larger) stock Types

side-stub: nursery trees too large for whip-and-tongue, not large enough for cleft

side-tongue: useful for broad- and narrow-leaved evergreens (e.g., oriental arbovitae)

side-veneer: useful for small potted plants, e.g., upright junipers

Approach graftingApproach grafting two independent plants are grafted together

after union, the top of the stock and the base of the scion are removed

used when other methods are unsuccessful (e.g., Camellia)

often done on plants in containers three methods: spliced-, tongued-, and inlay-approach grafting

Repair graftingRepair grafting Inarching Bridge grafting

InarchingInarching used for repairing damaged roots of a full-grown tree.

seedlings are planted around the tree during the dormant season, grafting is done in the spring.

Bridge graftingBridge grafting used for repairing a damaged trunk

early spring (with the bark slipping) is the best time

(dormant) scion wood should be 1/4 to 1/2 in. diam.

Technique Date Use

Bark grafting Mid-April through mid-May Establish a pollinating variety on a limb of a tree or to completely topwork a tree.

Bridge grafting Mid-April through mid-May Repair trees girdled above the ground line.

Cleft grafting Late February and March Establish a pollinating variety on a limb of a tree or to completely topwork a tree. Limbs should be 1 inch or more in diameter.

Inarch grafting Mid-April through mid-May Repair trees girdled at or below the ground line. Also used if a root disease is suspected or feared.

Saw-kerf grafting February and March On peaches, nectarines and plums to completely topwork a tree.

Whip grafting February and early March Propagate 1-year-old rootstocks. May also be used to establish a pollinating limb on a young, established tree.

The Biology of The Biology of GraftingGrafting

Natural graftingNatural grafting◦ Bracing of limbs in commercial orchards to Bracing of limbs in commercial orchards to

support weight of fruitsupport weight of fruit

◦ Root grafting in woods is prevalent (CHO’s of Root grafting in woods is prevalent (CHO’s of upper canopy trees provide support for upper canopy trees provide support for understory trees). This grafts only occur understory trees). This grafts only occur between trees of the same speciesbetween trees of the same species

◦ Problems with root grafting include: Problems with root grafting include: transmission of fungi, bacteria and viruses transmission of fungi, bacteria and viruses between plants (Dutch Elm Disease spreads between plants (Dutch Elm Disease spreads this way)this way)

The Biology of The Biology of GraftingGrafting

Formation of the graft unionFormation of the graft union◦A “de novo” formed meristematic A “de novo” formed meristematic

area must develop between scion area must develop between scion and rootstock for a successful graft and rootstock for a successful graft unionunion

3 events3 events◦1) adhesion of the rootstock & scion1) adhesion of the rootstock & scion◦2) proliferation of callus at the graft 2) proliferation of callus at the graft

interface = callus bridgeinterface = callus bridge◦3) vascular differentiation across 3) vascular differentiation across

the graft interfacethe graft interface

The Biology of The Biology of GraftingGraftingSteps in graft union formationSteps in graft union formation◦ 1.) lining up of the vascular cambium of 1.) lining up of the vascular cambium of

rootstock and scion. Held together with wrap, rootstock and scion. Held together with wrap, tape, staples, nails or wedged togethertape, staples, nails or wedged together

◦ 2.) wound response2.) wound response Necrotic layer 1 cell deep forms on both scion and Necrotic layer 1 cell deep forms on both scion and

stockstock Undifferentiated callus tissue is produced from Undifferentiated callus tissue is produced from

uninjured parenchyma cells below the necrotic layeruninjured parenchyma cells below the necrotic layer Callus forms a wound periderm (outer “bark”) which Callus forms a wound periderm (outer “bark”) which

becomes suberized to prevent entry of pathogensbecomes suberized to prevent entry of pathogens Necrotic layer dissolvesNecrotic layer dissolves

The Biology of The Biology of GraftingGrafting

◦3.) callus bridge formation3.) callus bridge formation Callus proliferates for 1 - 7 daysCallus proliferates for 1 - 7 days Callus mostly comes from Callus mostly comes from scionscion (due (due

to basal movement of auxins and to basal movement of auxins and CHO’s, etc.)CHO’s, etc.)

An exception to this is on established An exception to this is on established rootstock which can develop more rootstock which can develop more callus than that from the scion. callus than that from the scion.

Adhesion of scion and stock cells with Adhesion of scion and stock cells with a mix of pectins, CHO’s and proteins. a mix of pectins, CHO’s and proteins. Probably secreted by dictyosomes Probably secreted by dictyosomes which are part of the Golgi bodies in which are part of the Golgi bodies in cells.cells.

The Biology of The Biology of GraftingGrafting

◦4.) Wound-repair : First the xylem and then the phloem is

repaired Occurs through differentiation of vascular

cambium across the callus bridge Process takes 2 - 3 weeks in woody plants

◦5.) Production of 2º xylem and phloem from new vascular cambium in the callus bridge Important that this stage be completed

before much new leaf development on scion or else the leaves will wilt and the scion may die

The Biology of The Biology of GraftingGrafting

Some water can be translocated through callus cells but not enough to support leaves

Cell-to-cell transport via plasmodesmata = symplastic transport (links cells membranes)

Apoplastic transport is between adhering cells

Graft IncompatibilityGraft IncompatibilityCompatibilityCompatibility = = ability of two ability of two

different plants grafted different plants grafted together to produce a together to produce a successful union and continue successful union and continue to develop satisfactorilyto develop satisfactorily

Graft failureGraft failure:: caused by caused by anatomical mismatching/poor anatomical mismatching/poor craftmanship, adverse craftmanship, adverse environment, disease and environment, disease and graft incompatibilitygraft incompatibility

Graft IncompatibilityGraft IncompatibilityGraft incompatibility from:Graft incompatibility from:

◦Adverse physiological responses Adverse physiological responses between grafting partnersbetween grafting partners

◦Virus transmissionVirus transmission◦Anatomical abnormalities of the Anatomical abnormalities of the

vascular tissue in the callus vascular tissue in the callus bridgebridge

Graft IncompatibilityGraft IncompatibilityExternal symptoms of External symptoms of

incompatibilityincompatibility◦ Failure of successful graft or bud union Failure of successful graft or bud union

in high percentagesin high percentages◦ Early yellowing or defoliation in fallEarly yellowing or defoliation in fall◦ Shoot die-back and ill-healthShoot die-back and ill-health◦ Premature deathPremature death◦ Marked differences in growth rate of Marked differences in growth rate of

scion and stockscion and stock Overgrowth at, above or below the graft unionOvergrowth at, above or below the graft union Suckering of rootstockSuckering of rootstock Breakage at the graft unionBreakage at the graft union

Graft IncompatibilityGraft Incompatibility

Anatomical flaws leading to Anatomical flaws leading to incompatibilityincompatibility◦Poor vascular differentiationPoor vascular differentiation◦Phloem compression and vascular Phloem compression and vascular

discontinuitydiscontinuity◦Delayed incompatibility may take 20 Delayed incompatibility may take 20

years to show up (often in conifers years to show up (often in conifers and oaks)and oaks)

Graft IncompatibilityGraft IncompatibilityPhysiological and Pathogen-Induced Physiological and Pathogen-Induced

IncompatibilityIncompatibility◦ Non-translocatableNon-translocatable = localized. = localized.

Problem is fixed by using mutually Problem is fixed by using mutually compatible interstock(no direct contact compatible interstock(no direct contact between scion and stock)between scion and stock)

◦ TranslocatableTranslocatable = spreads. Interstock = spreads. Interstock does not solve the problem. Some does not solve the problem. Some mobile chemical causes phloem mobile chemical causes phloem degradation. Ex: cyanogenic degradation. Ex: cyanogenic glucosides like prunasin is converted to glucosides like prunasin is converted to hydrocyanic acid (from Quince to pear)hydrocyanic acid (from Quince to pear)

Graft IncompatibilityGraft Incompatibility◦Pathogen-induced virus of Pathogen-induced virus of

phytoplasma inducedphytoplasma induced◦TristezaTristeza = viral disease of = viral disease of

budded sweet orange that is budded sweet orange that is grafted onto infected sour grafted onto infected sour orange rootstockorange rootstock

Graft IncompatibilityGraft IncompatibilityCorrecting incompatible Correcting incompatible

combinationscombinations◦Generally not cost-effective. Generally not cost-effective.

Remove and top-work the Remove and top-work the rootstockrootstock

◦Bridge graft with a mutually Bridge graft with a mutually compatible rootstockcompatible rootstock

◦ Inarch with a seedling of Inarch with a seedling of compatible rootstockcompatible rootstock