Diseases and Management of Crops under Protected Cultivation

(Diseases and Management of Crops under Protected Cultivation)
this technique. The scion shoot of pencil thickness, with 3 to 4 healthy buds of 15-18 cm long is
used for grafting. Selected scion shoots are defoliated on the mother plant, about 5-7 days prior to
detaching. At the same time, the apical growing portion of selected shoot is also beheaded. This
helps in forcing the dormant buds to swell. In this way, the buds on the scion are ready to start
sprouting at the time of grafting. This treatment is essential for high success of grafts. After
selection of the scion, rootstock (seedling) is headed back by retaining 15-18 cm long stem above
the soil level in the polyethylene bag. The beheaded rootstock is split to about 4.0 - 4.5 cm deep
through the centre of the stem with grafting knife. A wedge shaped cut, slanting from both the
sides (4.0 -4.5 cm long) is made on the lower side of the scion shoot. Care must be exercised to
match the cambium layer of the stock and scion along with full length of each component. The
union is then tied with the help of 150 gauge polyethylene strip, 2 cm in width and 25 - 30 cm in
length. Immediately after grafting, the graft is covered by 2.5 x 18.0 cm long white polyethylene
cap which is tied with rubber band at the lower end.
Aonla (Emblicaofficinalis Gaertn)
Commercial Cultivars :Chakiya, Kanchan, Krishna, Narendra Aonla-6, Narendra Aonla-7,
Narendra Aonla-10
Raising of rootstocks
Aonla is commercially propagated by budding/ grafting on seedling rootstock. Fruits are
collected from local seedling (desi) aonla trees and used for rootstock raising. Mature fruits should
be collected during January/February. Fruits are dried in open and seeds are extracted by
applying light pressure. One kg seed can be obtained from one quintal of desi aonla fruits. Raising
of seedling is essential for rootstock. The timing for sowing of seed has been standardized.
Sowing of seed on raised bed (after soaking in water for 12 hours) or in poly bag during March/
April facilitates quick germination. Germination of seeds of aonla is better during March-April and
July-September.
Patch Budding
Six months to one-year old seedlings are used as rootstock for budding. The scion shoots
should be selected from the mother plants, which are prolific bearers and free from disease and
pest incidence. Patch/ modified ring budding during mid of May to September gives 60 to 90 per
cent success under north Indian conditions. However, in south India, aonla propagation is being
done almost 8-10 months in a year with the aid of greenhouse and net house facilities. Besides
budding, veneer and soft wood grafting are also successfully attempted with about 70 per cent
success. However, considering the efficiency, budding appears to be an ideal method for aonla
propagation. Propagation of aonla in poly bags/poly tubes, or in situ orchard establishment
(particularly in the drier areas) have been standardized and needs popularization. Aonla scion
shoots can safely be stored/ transported in sphagnum moss / moist newspaper for 5-7 days with
ample success.
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