Thursday 4 July 2013

Stone grafting method

Stone Grafting
In the tropics and sub-tropics, many farmers like to plant mango trees.Demand for good fruit is
increasing, and farmers are understanding the benefits of this. Farmers want to plant mangos, but often the seedlings aren't available, or if they are,they're expensive. But there is an easy way of producing good quality mango seedlings. This is called Stone Grafting.Using this method,mango seedlings can be grown quickly and cheaply at home, producing good quality fruit. Grafted trees also are fast to produce fruit. This means that poorer farmers can easily plant mangos without going into debt, and get faster benefits.
 Nowadays most mango grafting is done using the"In arching" method. But this takes 2-3 years to produce a seedling,which is why mango seedlings are so expensive. Also, in Nepal, the skilled grafters live in the south, so it is difficult to obtain mango seedlings in the poorer northern hill districts.Transport is expensive, and many seedlings can die during the journey in the hot summer,when they are distributed. Seedlings costings 2 or 3 times as much after they have been transported from the nursery into more remote hill districts.So there are many benefits from using stone grafting to produce mango seedlings • quick production - while it takes 2-3 years to produce a
seedling for distribution with in arching, it takes 2 months with stone grafting;
• stone grafted seedlings are cheap to produce
• stone grafting is an easy method
• many seedlings can be produced in a small place, unlike
in arching
• seedlings can be produced near to where they are to be
planted
 How to do Stone Grafting
 1. Planting the Seed
• Fill the poly pots with fertile
soil.• Dig a trench for the nursery bed, about 4-6 inches deep. The width and length of the trench
depends on how many seedlings are to be produced.• Lay out the thick plastic in the base of the trench.• Place the filled poly pots in the trench.• Collect ripe seed from healthy, disease free
wild local mango trees. They ripe nat just the right time for stone grafting.• Sow the seed in the poly pot and cover with the soil.• Watch for when the seed starts to germinate. Within a week,
the first seeds will start to grow, but they won't all start at the same time. Keep the sprouted pots in one place.
2. Preparing the Scion A scion needs to be cut and brought from a healthy, good fruiting
mango tree. This is called the mother tree. Before the scion is cut it needs to be prepared while
still on the mother tree, and the time to do this depends on when the rootstock seed had sprouted in the nursery. Five to seven days after the seed has sprouted in the nursery, you need to go to the mother tree and prepare the scion. However many seedlings in the nursery are 5-7 days old, the same number of scions need to be prepared on the mother tree.
Preparing the Scion
Go to the mother tree and select branches for scions. If the branch has red sprouting tips, then it
is suitable to use as a scion. The branch and tip should be healthy and disease free. Now trim off the leaves around the tip for a length of about 6 inches, but don't trim the tip itself.
3. Cutting the Scion
The trimmed branch will be cut for use as a scion to join to the rootstock, but not yet. It will be

another week before this is done, and until that time the trimmed, red branch tip will remain on the mother tree.
• After 7 days return to the mother tree to collect the scion.
• Using secateurs or a sharp tool, cut the branch 6 inches from the red tip. As soon as it has been cut, put the scion in a glass of water. This is because it is very soft and will otherwise dry out quickly.
• When the scion is in the glass, trim each leaf as shown. This also reduces water loss.
• Now take the scion to the nursery, where it should be grafted immediately onto the rootstock.
4. Grafting the scion to the
rootstock
• By this time, the seedlings growing from the local, wild mango seed should be 12-14 days old. Their leaves and stem should be soft and red, like the scion on the mother tree.

 Methods of grafting and budding

Specific methods, appropriate seasons for grafting and budding selected fruit and ornamental plants, along with suitable root stocks.
• Splice (also called whip) grafting is the simplest way to join a stock and scion. It is best suited for herbaceous plants in a protected location. The stock and scion should be less than 1 inch in diameter and of equal thickness. Make long, diagonal cuts of equal length on stock and scion. Fit cut surfaces of stock and scion together and use tape or other tying materials to hold the parts together. Additional protection with wax . When the diameter of stock and scion are not equal, the scion should be placed to one side of the stock to ensure cambial contact on at least one side. 
Side-veneer graft: Make a shallow cut, about 1.5 inches long at the base of the stock, directed slightly inward . At the base of this cut, make a short inward, downward cut to intersect the first cut, thus allowing removal of a piece of wood and bark. Prepare the scion with a long cut the same length and width as that of the first cut on the stock. Make a short cut on the opposite side of the base of the scion. Insert the scion in the stock with the long cut of the stock next to the long cut on the scion. Secure the scion by wrapping with tape or rubber budding strips. Cover the graft region with a protective material. When the graft union forms, cut off the stock just above the union.

 Inarching Method

  • For inarching, first the seedlings are to be raised. Stones are sown in beds immediately after extracting them from the ripe fruits.
  • If extracted and kept for a longer period, stones lose their viability completely.
  • Stones when stored in the open lose viability completely after 70 days, whereas those buried under sand retain 12.5% viability after 90 days.
  • Similarly, the seeds mixed with charcoal and sealed in tins or earthen pots retain their viability only for 80 days at room temperature. But those sealed in polythene bags with charcoal retain 37.5% viability after 100 days at room temperature and 17.5% viability after 120 days at 20-230 C.
  • However, storage of mango stones at 5-80 C seems to be harmful, as there is complete loss of viability after 20 days.
  • A spacing of 22 cm from seed to seed in the row and about 45 cm from row to row is usually adopted. Beds should be kept clean of weeds.
  • After about a year, the seedlings become ready for inarching. Seedlings should be carefully watched for vegetative malformation in the nursery bed and these must be culled in the beginning, as there is as yet no method to cure this in the nursery stage.
  • Such seedlings should invariably be avoided for grafting. These seedlings can later on be transferred either to pots or taken out (with ball of earth around the roots tied with grass all round to check the evaporation of water and to keep the roots intact) for inarching operation.
  • These should be taken to the tree from which the scion part is to be selected and kept or tied up conveniently to facilitate the process of inarching.
  • Sometimes the scion parent is headed back to produce a large number of conveniently available branches for grafting at ground level.
  • The technique of raising mango seedlings for inarching followed by the nurseries in Malihabad (Lucknow) is a scientific one.
  • Seeds are sown in the nursery bed, and when the seedlings are about 12 cm the whole bed is scrapped with the help of a khurpi taking care that stones remain uninjured and only the main root is cut.
  • These seedlings are transplanted afresh, and after about a few months these are again transferred to other beds.
  • This checks the development of main root and thus ultimately facilities the lifting of the plants with smallest ball of earth without any undue injury to the roots.
  • The scion plant is about 2-3 years old. It is kept prostrate in the bed during rainy season so that a few branches arise from the exposed side of the plant.
  • The seedlings are ultimately taken out from the nursery bed and planted just near this parent scion plant.
  • The actual process of inarching consists of removal of a strip of bark, about 6.0-7.5 cm long with a small layer of wood attached to it, from the potted seedling at a height of 22 cm from soil surface.
  • A similar strip is then removed from the scion shoot selected for inarching. The scion shoot should be healthy with well-developed foliage.
  • Care is taken to ensure that the 2 exposed surfaces on the seedling and the scion shoot fit together securely, leaving no gap when the 2 treated shoots are held together by hand with the exposed parts in contact with each other.
  • In this position they are tied firmly with raffia or banana fibre. The complete operation should be done at the commencement of rains for successful raising of the plants.
  • The inarching is done in October by the nurserymen in Malihabad when the rains are over.
  • Mango leaf and ordinary sutli are used for wrapping and tying the cut portions. While raising of mango stock seedlings is very scientific, for root distribution and for the small ball of earth required while taking out the plant from the nursery the method of raising scion material is unscientific-because the scion wood is taken without the knowledge about the performance of the parent material.
  • However, it has the following disadvantages:
    1. The rootstock seedlings are brought near the mother plant, so it is more cumbersome.
    2. It is laborious and time consuming.
    3. The inarched plants are irrigated regularly and care is required for 2-3 months at the place of mother plant.
    4. Only one plant is obtained from a long scion shoot so it is uneconomical.
    5. Usually one-year-old rootstock seedlings are planted/potted which causes high percentage of mortality during inarching.