Origin and distribution
Wild Himalayan Aonla belongs to the family Phyllanthaceae. It is believed to be originated to tropical Southeast Asia, especially parts of Central and South India. It occurs in Pakistan, Ceylon, Malaysia, Southern China and Mascarene Island. It is called as Indian gooseberry and by various vernacular names i.e. Amlaki, Amla, Amluki, Amli, Aonla, Amalkamu, Nelli in India. In India, the domestication first began in Kashi (Varanasi) in Uttar Pradesh where Baranasi a superior variety was developed by selection from wild Aonla trees available in large number bear by Vindhyachal range, is still considered one of the best varieties. The rich diversity of Aonla exists in North-East region of India particularly lower Assam, Meghalaya, Mizoram and Tripura and in the Shivalik region of western Himalaya.
Aonla tree is deciduous, small to medium in size, 5-6 m tall. The bark is usually light brown to black. The main trunk is divided into 2-7 scaffolds 1-2 m above the base. Leaves are pinnate, 10-15 mm long, 2-3mm wide, making the branches feathery in general appearance. The leaves develop after the fruit-set. Flowers are unisexual (staminate and pistillate), tubular at the base, pale green, 4 to 5 mm in length, borne in leaf-axils in clusters of 6 to 10, having a very small stalk, gamosepalous, having 6 lobes at the top, stamens 1 to 3, polyandrous, filaments 2 mm long, pistillate flowers, fewer, having a gamopetalous corolla arid a two-branched style.
Both staminate and pistillate flowers are borne on the same branch, but the staminate flowers occur towards the apices of small branches. Fruits are pale green to dark green, round, fleshy, almost depressed to fruit apex, 1.5-2.5 cm in diameter and 5-6 g in weight. The stone of the fruit are citron green, six-ribbed, splitting into three segments, each containing usually two seeds, seeds 4-5 mm long, 2 to 3 mm wide and each weighing 500-550 mg.
Nutritional value and uses
The fruit pulp, which constitutes 90.97% of whole fruit, contains 70.5% moisture. The total soluble solids constitute 23.8% of the juice. The acidity of Aonla is 3.28% on pulp basis. The pulp contains 5.09% total sugars and 5.08% reducing sugars. The ascorbic acid content is 1,094.53 mg per 100 ml of juice. The tannins and pectin content of the pulp is 2.73% and 0.59% respectively. The fruit pulp contains 0.75% protein while the mineral content of the edible portion is 2.92%. The wild Aonla fruits are used for making pickles and preserves.
Dried fruits are used in making “triphala”, “chyavanprash”. The fruits and bark are rich in tannin are used in leather industry. Wild Aonla has tolerance to frost which may help in the diversification of Aonla cultivation in other areas of plains where frost is a major problem. The plant is considered to be an effective antiseptic for cleaning wounds. The leaves of Aonla are used as a mouth wash and as a lotion for sore eyes. An ointment is made from the burnt seeds and applied to cure skin infections. The fruits are diuretic and laxative. They are useful in the disorders associated with the digestive system and also prescribed in the treatment of jaundice and coughs.
Wild Aonla grows well in sub-tropical cool-humid climate on variable soils but commercial cultivation needs soil which is rich in humus and well drained. It can be propagated through seeds, however, prolonged juvenility and wide variability may take place. Selected promising genotypes from wild Aonla populations may be used for budded or veneer grafting on six months to one year old seedlings of wild aonla as rootstock. To raise the seedlings mature wild aonla fruits are collected during January-March and seeds are extracted after drying.
Seeds are sown in raised beds in the month of April onwards and transplanted in separate bed for subsequent budding or grafting. Grafted or budded plants are planted 7-10 m apart in the pits of 1x1x1 m size during July-August or February. Pits should be filled with 20-30 kg well rotten FYM and 500 g of bone meal.
Filled pits need to be irrigated if planted in winters. Tree can be trained to modified central leader system. Two to four branches with wide crotch angle, appearing in opposite direction encouraged in early years. Unwanted branched should be pinched off during March-April. However, dead, infested, broken or overlapping branches should be removed regularly.
A dose of 10 kg FYM, 100 g N, 50 g P, and 100 g K should be given to one year old plants of aonla each year. This dose should be increased yearly up to 10 years. Flowering season may vary from place to place, but in general, it occurs from the middle of April to first week of May. The fruiting season of wild aonla also varies from place to place in Himachal Pradesh, but at most of the places, it is harvested in winters.
- National Bureau of Plant Genetic Resources Regional Station , Phagli, Shimla