Temprate Fruits (1+1)

ROOTSTOCKS AND PROPAGATION

Apple is propagated by asexual method of grafting and budding on rootstocks.

Rootstocks:

(1) Seedling rootstocks

• Seedling rootstocks are vigorous and not uniform in size.
• Seeds of crab apple (Malus baccata) or self pollinizing varieties like Golden Delicious and Granny Smith are used for raising seedling rootstocks.

(2) Clonal rootstocks

• Clonal rootstocks are precocious, uniform and resistant to some insect pests and diseases.
• In recent years size controlling clonal rootstocks are gaining popularity especially for establishment of high density.
• The promising clonal rootstocks of apple are:
• M9 or EMLA9 and M26 or EMLA26 (Dwarf)
• M7 or EMLA7, MM106 or EMLA106 ( Semi dwarf)
• MM111 or EMLA111 (Semi vigorous)
• Merton 793 ( vigorous)
• Malling series( M) rootstocks are size controlling but not resistant to woolly apple aphid.
• Malling Merton series (MM) are size controlling and resistant to woolly apple aphid.
• EMLA series rootstocks are virus free.

Propagation
Propagation of rootstocks

(a)Seedling rootstock

• Seeds of apple are dormant, which require stratification treatment (moist chilling) to break dormancy.
• Seeds are stratified for 60-70 days in alternate layers of moist sand at 4-6 oC during December to February.
• The stratified seeds are sown in nursery beds during March at a spacing of 8-10 cm from seed to seed and 15-20 cm from line to line.
• After sowing, the nursery beds are mulched with 10 cm thick dry grass and light irrigation is given to avoid desiccation of stratified seeds.
• Mulch is removed as soon as seed start germinating.
• Cultural operations like weeding, hoeing, irrigation and spray of insecticide and fungicides are done at regular intervals.
• The seedling rootstock attain graftable size of 15 mm diameter in a year.

(b)Clonal rootstock

• The clonal rootstocks are commercially propagated through mound layering or trench layering (Fig 1 and 2)

Propagation of scion

• The commercial method of propagation of apple scion varieties is grafting and chip budding.
• For grafting and budding the scion wood should be collected from healthy, disease free, true to type mother trees during January.
• The scion wood is collected from one year old shoots and packed in moist sphagnum moss, after proper labeling of variety.
• These bundles of scion wood are stored in cold storage or buried deep in the soil at shady place till required for grafting .
• The best time of grafting of apple is February to March with tongue and cleft methods.
• Chip budding can also be done in March and July.

PLANTING AND PLANTING DENSITY

• The best time of planting of apple is January - February.
• The planting distance varies according to variety, rootstock and fertility status of soil.
• Before planting, orchard layout should be planned. In flat land square or hexagonal system of layout is adopted, whereas in sloppy land contour and terrace system of layout is done.
• After layout of an orchard, the pits of 1x1x1 m size are dug well in advance of planting.
• The pits are filled atleast one month before planting with soil in which 40-50 kg well rotten FYM and 1 kg single super phosphate are mixed.
• After planting, watering is done and tree basins are mulched with 10 cm thick dry grass, which helps in conserving the soil moisture and control the weed population.
• In apple, most of the varieties are self unfruitful, therefore, at the time of planting proper proportion of pollinizer varieties (25 or 33%) should be planted in the orchard.

Table 3 Spacing and planting density for different scion stock combinations

Fruit crop	Scion/variety	Rootstock	Tree size	Spacing (m)	Density (trees/ha)
Apple	Standard	Seedling	Vigorous	7.5 x 7.5	178
	Standard	MM111 and Merton 793	Semi vigorous	6.0 x 6.0	278
	Standard	MM106, M7	Semi dwarf	4.5 x 4.5	494
	Standard	M9 and M26	Dwarf	1.5 x 1.5	4444
	Spur type	Seedling	Semi vigorous	5.0 x 5.0	400
	Spur type	MM111, Merton 793	Semi dwarf	3.5 x 3.5	816
	Spur type	MM106, M7	Dwarf	3.0 x 3.0	1111