Citrus fruits are a group of fruits comprising of Mandarins, Sweet Oranges, Grape Fruit, Limes & Lemons etc. Citrus fruits have a prominent place among popular, extensively grown tropical & subtropical fruits. In India citrus is considered to be the third most important fruit crop. It has highest value in terms of international trade.
Rootstocks
A rootstock is part of a plant, often an underground part, from which new above-ground growth can be produced. The stock & scion must be compatible & should be capable of producing long lived, productive trees. The influence of the most important & widely used rootstocks & their characteristics should be known to the grower for choosing the right kind of the stock for the locality.
The most commonly used stocks for sweet orange as well as mandarins in India are Jamberi (Rough Lemon) & Karnakhatta.
The characteristics of different rootstocks:
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Jamberi:With a greater number of seeds, high percentage of germination & polyembryony is a vigorous stock for sathgudi The tree top is oval. Fruits are large, rind is rough & thick & juice is insipid (Tasteless). Morality is very high due to quick decline or other diseases out of use.
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Ganjanimma:It has all the good nursery characters of Jamberi & has a profilic but is susceptible to gummosis & collar not resulting in high mortality & hence disordered.
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Trifoliate Orange:It is hardiest root stock & does well in forestry areas. Resistant to many virus diseases. The plant gets dwarfed on this rootstock & is frost resistant.
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Karnakhatta: It is found to be most common & satisfactory rootstock for grape fruit, for heavy & wet soil to Punjab & U.P.
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SathgudiSeedling: Suitable for moderately heavy soils. It gives smooth joint. The trees are long lived being tolerant to decline. Yields are moderate. Fruits are of fine quality & good keeping quality.
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Rangpur Lime:It is used as stock for Mosambi in Bombay region. It is a vigorous grower, resistant to many of the virus diseases chiefly Tristeza virus. It gives high yields with fruits of much better quality & hence recommended as stock for sweet orange.
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Acid Lime: Slow growth. Thorns make it difficult to bud. Resistant to high water table conditions.
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Kichili:Drought resistant. Slow growth & gives a globular tree.
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Pummelo:It has given a dwarf tree
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Wood apple:Dwarfs sathgudi very much. Reduces prebearing period, longevity & yield but increases the sweetness of fruit.
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Sweet Lime:It is satisfactory stock for Nagpur Santhra with better quality & tighter skin.
