kuldeep garwa
DESCRIPTION
TRANSCRIPT
![Page 1: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/1.jpg)
Propagation Propagation by Graftingby Grafting
PROPAGATION OF HORTICULTURAL CROPS AND NURSERY MANAGEMENT
SUBMITTED BY ; SUBMITTED TO;
Kuldeep garwa Dr. L.N.Mahawar
![Page 2: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/2.jpg)
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:
![Page 3: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/3.jpg)
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
![Page 4: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/4.jpg)
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:
![Page 5: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/5.jpg)
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:
![Page 6: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/6.jpg)
Reasons for grafting Reasons for grafting plantsplantsTo propagate
plants which cannot be economically propagated by other techniques
Eg. Cultivars of ornamental shrubs and trees
![Page 7: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/7.jpg)
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
![Page 8: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/8.jpg)
Reasons for grafting Reasons for grafting plantsplantsTo confer
resistance to pathogens to the grafted plant
Eg. WaxflowersEg. AvocadosEg. GrapesEg. Tomatoes
![Page 9: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/9.jpg)
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
![Page 10: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/10.jpg)
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
![Page 11: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/11.jpg)
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
![Page 12: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/12.jpg)
![Page 13: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/13.jpg)
Grafting practice with students
![Page 14: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/14.jpg)
![Page 15: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/15.jpg)
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
![Page 16: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/16.jpg)
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:
![Page 17: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/17.jpg)
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:
![Page 18: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/18.jpg)
Scion wood Should be One or twoYears old
![Page 19: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/19.jpg)
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:
![Page 20: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/20.jpg)
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:
![Page 21: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/21.jpg)
METHODS OF GRAFTING
![Page 22: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/22.jpg)
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
![Page 23: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/23.jpg)
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
![Page 24: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/24.jpg)
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.
![Page 25: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/25.jpg)
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.
![Page 26: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/26.jpg)
![Page 27: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/27.jpg)
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
![Page 28: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/28.jpg)
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.
![Page 29: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/29.jpg)
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
![Page 30: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/30.jpg)
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
![Page 31: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/31.jpg)
Grafting MethodsGrafting Methods Bench grafting
Field methods
Container or field methods
Repair grafting
![Page 32: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/32.jpg)
Bench graftingBench grafting Whip-and-tongue graft Saddle graft
![Page 33: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/33.jpg)
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
![Page 34: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/34.jpg)
Whip and Tongue GraftingWhip and Tongue Grafting
Cut a shallow angle
![Page 35: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/35.jpg)
![Page 36: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/36.jpg)
Whip and Tongue GraftingWhip and Tongue Grafting
Use the pith as center and split the stem. Note finger position!
![Page 37: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/37.jpg)
Look at that finger position again!
Please don’t cut yourself!
![Page 38: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/38.jpg)
Whip and Tongue GraftingWhip and Tongue Grafting
Repeat the same cuts with the scion wood except cut the bottom of the scion.
![Page 39: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/39.jpg)
Whip and Tongue GraftingWhip and Tongue Grafting
Push rootstock and scion together with cambium lined up on one side.
![Page 40: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/40.jpg)
Whip and Tongue GraftingWhip and Tongue Grafting
![Page 41: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/41.jpg)
Whip and Tongue GraftingWhip and Tongue Grafting
Wrap the whole graft and also the tip of scion.
![Page 42: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/42.jpg)
Healed GraftHealed Graft
![Page 43: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/43.jpg)
![Page 44: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/44.jpg)
![Page 45: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/45.jpg)
Figure 1 Figure 2A (top), Figure 2B (bottom)Figure 3A (left), Figure 3B (right)
![Page 46: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/46.jpg)
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
![Page 47: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/47.jpg)
![Page 48: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/48.jpg)
Field methodsField methods Cleft graft
Wedge graft
Bark graft
![Page 49: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/49.jpg)
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
![Page 50: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/50.jpg)
![Page 51: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/51.jpg)
![Page 52: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/52.jpg)
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
![Page 53: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/53.jpg)
Figure 23 Figure 24Figure 25 Figure 26
![Page 54: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/54.jpg)
Container or field Container or field methodsmethods
Side grafts Approach grafts
![Page 55: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/55.jpg)
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
![Page 56: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/56.jpg)
![Page 57: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/57.jpg)
![Page 58: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/58.jpg)
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
![Page 59: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/59.jpg)
![Page 60: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/60.jpg)
Repair graftingRepair grafting Inarching Bridge grafting
![Page 61: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/61.jpg)
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.
![Page 62: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/62.jpg)
![Page 63: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/63.jpg)
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.
![Page 64: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/64.jpg)
![Page 65: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/65.jpg)
![Page 66: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/66.jpg)
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.
![Page 67: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/67.jpg)
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)
![Page 68: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/68.jpg)
![Page 69: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/69.jpg)
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
![Page 70: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/70.jpg)
![Page 71: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/71.jpg)
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
![Page 72: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/72.jpg)
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.
![Page 73: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/73.jpg)
![Page 74: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/74.jpg)
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
![Page 75: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/75.jpg)
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
![Page 76: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/76.jpg)
![Page 77: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/77.jpg)
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
![Page 78: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/78.jpg)
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
![Page 79: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/79.jpg)
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
![Page 80: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/80.jpg)
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)
![Page 81: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/81.jpg)
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)
![Page 82: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/82.jpg)
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
![Page 83: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/83.jpg)
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
![Page 84: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/84.jpg)
![Page 85: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/85.jpg)
![Page 86: Kuldeep garwa](https://reader031.vdocuments.mx/reader031/viewer/2022012401/54839e87b4af9ff8228b45cd/html5/thumbnails/86.jpg)