Abstract
Possibility of artificial regeneration through vegetative propagation of Aegiceras corniculatum (Myrsinaceae) was studied. Rooting in air-layer was induced with the aid of root promoting substances like IAA, IBA and NAA. Maximum rooting ability (in terms of percentage of rooting and root number) was recorded in the air-layers treated with IBA 2500 +NAA 5000 ppm with a promising rate of survivability. Untreated air-layers, however, did not produce any root. Anatomical and biochemical changes were investigated during rooting. Exogenously applied auxins hastened rooting by stimulating cambial activity resulting in the formation of root primordia from phloem parenchyma and eventual root emergence after 27 days of treatment. The rooting response in the air-layers might be determined by higher level of carbohydrate and lower level of nitrogen (a high C/N ratio) especially at the root initiation stage which was confirmed by the activity of amylase, a hydrolysing enzyme. The metabolism of auxins during rooting might be due to enhanced activity of peroxidases and polyphenol oxidase, which had a protective and preparatory role on auxins. Present study revealed a high possibility of scaling up propagation of Aegiceras corniculatum, an economically important tree mangrove through air-layering for use in afforestation programmes.
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