INTRODUCTION:

Global food security has become increasingly dependent on a handful of crops. Over 50 percent of the daily global requirement of proteins and calories is met by just three crops maize, wheat and rice¹and only 150 crops are commercialized on a significant global scale. On the other hand, ethnobotanical surveys indicate that worldwide, more than 7,000 plant species utilized by humans are rather cultivated or harvested from wild ^{2, 3}.

It is obvious that the underutilized food plants will ensure a more nutritive and healthy food security. Efforts from the authorities are also inevitable to promote the conservation and sustainable utilization of underutilized food plant species to maintain biodiversity and to provide food security in the country. Plants are vital for existence of life on earth. The plants around the habitats of the rural populations not only provide food for living organisms, but also provide different chemicals necessary for human health. Rural women are often the major players in utilizing wild traditional food plants including vegetables. The greens provide a rich source of minerals and vitamins. Besides the common leafy vegetables and greens, a number of other plants are also consumed particularly by the indigenous community. The habitat degradation and fragmentation of these forests have resulted in the depletion of natural resources on which these tribes used to depend on and it has become increasingly difficult for them to follow their traditional practice. Due to urbanization, their life style gets altered and it is visible that there is an increasing encroachment in and around the tribal settlements. Millions of people in many developing countries depend on wild resources including wild edible plants to meet their food needs especially at times of food crises¹⁰.

The 550 tribal communities, belonging to 277 ethnic groups, present perhaps the richest heritage of India. They account for about 7% of the population in India. A survey of the use of plants that the tribal communities make use of came out with staggering data of diversity. According to a recent study¹¹, over 10,000 wild plant species are reported to be used by tribals for meeting their primary healthcare, food and other material requirements. They use over 3,900 species of plants for edible purposes, over 8,000 for medicinal uses, another 1,000 for fodder, fibre and assorted purposes¹².

Some botanical explorations and publications have emphasized on the diversity and the value of wild edible plants ^{4, 5, 6, 7, 8, 9}. The information available on the homestead garden plants is rather scanty. Hence, it is felt that there is an urgent need to document the list of cultivated plants used by the tribal community, as this will enhance the nutritional status of local inhabitants and thus will pave the way for their importance and role in horticultural and agricultural fields. The objective of this study is to assess the utility of the cultivated edible plants used by the Irulars tribes in Coimbatore district forest region (Anaikatty). Similar ethnobotanical studies have been reported in several parts of India, so the study is undertaken to document the same, to protect the tribals traditional knowledge from vanishing and involve them in the conservation of these biological resources including their sustainable utilization.

MATERIALS AND METHODS:

Description of the Study Area:

The hill ranges of Western Ghats cover less than 6% of India’s landmass but harbour more than 30% of the world’s plant and vertebrate species¹³and are thus considered to be one of the global biodiversity hotspot¹⁴. The Western Ghats is a chain of mountainous ranges running from river Tapti in Gujarat to Kanniyakumari in Tamilnadu and is about 1600 km long in North-south direction. The study area Anaikatty hill is situated at a distance of 30 km from Coimbatore. The Nilgiri Biosphere which covers 5520 sq.km in the Western Ghats, was established by the Ministry of Environment and Forests, Government of India, to provide a means of conserving the endemic and threatened flora and fauna of the area. The site lies juxtaposed to the Perianaicken palayam Reserve forest on the east. Two hill slopes, northern and southern, also form a part of park. The hills elevate to a height of 80 to 120m from the valleys the temperature ranges from 18-37C¹⁵. There are few hill ranges in the study area, in this study 4 hamlets of Irulars namely Kondanur, Anaikatty, Sembbukarai, and Aalamaramedu were selected as study area. These hamlets are found at an altitude of 400-450 MSL.

Ethnobotanical Survey:

The field work was conducted in 4 hamlets around Anaikatty study area, Coimbatore District as part of a study of ethnobotanical observations on Irular tribe in Tamilnadu ^16. More than 150 families and nearly 600 members of Irulars are found in the study area. During the investigation, their daily activities were closely observed and interpersonal contacts were established by participating in several of their social functions like marriages, rituals and other festivals. There were 25 informants (15 females and 10 males) between the ages of 20-65 in the study area. Out of which 13 were farmers, 7 were house wives and rest of them were traditional healers.

Interviews with Tribal Community:

Ethnobotanical data was collected according to the methodology suggested by¹⁷. This was done through interviews, various direct observations at different study sites and discussions with the tribals in their own language. The specimens were collected and identified with the help of Flora of Presidency of Madras¹⁸ and The Flora of Tamilnadu Carnatic¹⁹ the nomenclature was checked by using ²⁰. The herbarium specimens were deposited in the Herbarium of the Department of Botany, Kongunadu Arts and Science College, Coimbatore.

Irular Tribes:

The indigenous people of the study area are called Irula/ Irulars. Irulars belong to forest hunting type of tribals. These Irulars are also known by different names including Eravallan, Erukala, Irava, Irular, Iruliga, Iruligar, Korava, being some of the prominent names. Each type of tribal communities has developed a different life style. They are found in the foot hills of Coimbatore and Nilgiri District and they depend upon the forest for their livelihood, hunting and gathering of minor forest products. It is believed that Irulars are indigenous people of Tamilnadu; in general they are illiterate and speak Tamil. Their main occupations are snake and rat catching and they also work as labourers (coolies) in the fields of the landlords during the sowing and harvesting seasons or in the rice mills. Irulars when compared to various tribal communities in Tamilnadu constitute relatively a small group.

RESULTS AND DISCUSSION:

The Irulars have a sound knowledge on the utility of wild plants along with cultivation of plants at their backyards for their personal consumption. A total of 75 species are enumerated in this investigation. As sources of cultivated plants, herbs are dominant with 25 species, shrubs with 18 species, climbers with 20 species and trees with 12 species. The Solanaceae recorded the highest number of species (8 species) followed by Cucurbitaceae and Amaranthaceae with 6 species, Euphorbiaceae and Lamiaceae with 4 species; Malvaceae and Oleaceae with 3 species each and the rest are represented with one or two species (Table 1). The Irulars who live in the jungles of the foothills of Western Ghats consume different varieties of roots, tubers, rhizomes, twigs/ leaves, fruits and seeds. From the edible wild plants identified as important sources of food the following parts were more commonly used: leaves 17 species; fruits 27 species; roots/ tubers/ bulbs/ corms/ rhizomes 6 species; seeds 5 species. 14 edible plant parts were consumed directly without any processing while 38 species (vegetables and spices) were processed somehow before consumption by the women. Some of the wild plant species had more than one edible part. After their personal consumption, any plant food items available in excess, are sold to the local consumers/markets.

In the forests of Anaikatty, the Irulars cultivate a large number of plant species which are used for food, medicine and other miscellaneous needs. Besides collecting wild plants from nearby forests, they also cultivated a variety of plants for their subsistence needs. However, this area of research has been neglected in research and development. The indigenous knowledge on the wild as well as cultivated plants has to be documented for serving future generations. Priority should be given to develop a system for the systematic recording of the information related to the ethnobotanical uses and indigenous knowledge of edible plant species.

Plant Parts used and Modes of Consumption:

The cultivated edible plants are consumed in different ways and are prepared using availability of recipes according to their local traditions. Some of them are eaten raw and many of them are cooked and thus require more or less complex preparation process. It is obvious that cooked (38) edibles predominate in the modes of consumption; while the raw consumption (14) gets a relatively low percentage. However, the high percentage of cooked edibles indicates the availability of plant resources near or around their habitations.

Plants Consumed as Raw Ones:

Within the study area, it is noticed that most of the plants with edible parts (the root, leaves and fruits) are eaten raw. The majority of the plants are eaten fresh, directly after they are gathered. The leaves and fruits of Solanum nigrum are eaten fresh for their medicinal value. Fruits yielding species like Mangifera indica, Annona squamosa, Carica papaya, Phyllanthus emblica, Phyllanthus acidus, Azadirachta indica, Psidium guajava, Syzygium cumini, Passiflora foetida, Punica granatum, Ziziphus mauritiana and Lycopersicon esculentum are also eaten raw: whereas the tuberous roots of Ipomoea batatas and Manihot esculenta were also taken raw as soon as they are collect removed from the garden.

Plants Consumed as Cooked:

The nutrient content of different types of vegetables varies considerably and they are not major sources of carbohydrates compared to the starchy foods which form the bulk of food eaten, but contain vitamins, essential amino acids as well as minerals and anti-oxidants. Vegetables are included in meals mainly for their nutritional value; however some are reserved for the sick and convalescence because of their medicinal properties²¹. Many of the cultivated plants have been cooked and eaten. Some plants are consumed after frying in the palm oil/ ground nut oil/ coconut oil. For example, the seeds are removed from the fruit of Solanum torvum, washed thoroughly with water and fried in the oil for culinary purpose.

The twigs of Amaranthus species, Alternanthera sessilis, Centella asiatica, Sesbania grandiflora, Basella alba, Chenopodium album, Portulaca oleracea, Portulaca quadrifida are mostly cooked and eaten. The fresh and dried fruits of Solanum melongena, S. torvum, S. nigrum, S. americanum are also cooked and consumed. The tuberous roots/ rhizomes of Ipomoea batatas, Manihot esculenta and Canna indica are also cooked and eaten.

Seasonings and Spices:

The leaves/shoots of Mentha arvensis, Murraya koengii and Coriandrum sativum, fruits of Capsicum frutescens, Capsicum annum and Coriandrum sativum are used for flavouring both in fresh and dry form.

Preserved Plants:

Very few plant species are gathered, served and to be preserved for consumption over a long period. Fruits are pickled in Citrus limon and Phyllanthus emblica; salt is used as preservative in Mangifera indica and used whenever needed.

Multiple uses including Medicinal uses:

The cultivated plants such as Solanum nigrum, S.americanum, S. torvum, Coccinia grandis, Cucurbita maxima, Psidium guajava, Carica papaya, Momordica charantia, Brassica juncea, Centella asiatica, Basella alba, Phyllanthus emblica, Luffa acutangula, Tamarindus indica, Chenopodium album, Alternanthera sessilis, Azadirachta indica, Musa paradisiaca, Oxalis corniculata, Solanum trilobatum, Cissus quadrangularis are used for their multiple purpose and most of them are cooked and eaten. Many of these plants are having therapeutic value in curing some common ailments.

Plants which are Sold in the Market:

Twigs/shoots of the plants like Alternanthera sessilis, Amaranthus spinosus, Amaranthus viridis, Oxalis corniculata and Portulaca oleraceae and fruits of Phyllanthus emblica, Phyllanthus acidus, Ziziphus mauritiana, Carica papaya, Psidium guajava, Annona squamosa, Solanum torvum, S. nigrum, S.americanum, Capsicum annum and Musa paradisiaca and fruits of Cucurbitaceae are sold in the market. The Irulars prefer some species like Alternanthera sessilis, Amaranthus viridis and A. spinosus and it is evident that they domesticate these species around their settlements. Using biotechnological tools, it is possible to develop new crops by domesticating the available wild edible species, especially in the tropical countries. In many developing countries, millions of purple depend on wild resources including wild edible plants to meet their food requirements especially in periods of drought and famine.

The present data on Irulars shows the importance of leafy vegetables in their daily diet. Out of the 75 species, 17 species of edible leaves are recorded from the study area. It is interesting to observe that most of the species are distributed throughout their habitations and their surroundings. ²² reported strong dependence on leafy vegetables for the food among the tribes of north-eastern region. Most of the vegetables form permanent food for the Irulars. ²³studies also reported that their kitchen gardens not only provide their daily requirements but also play a significant role in the economy of these two communities namely Puliyars and Muthuvars.

Apart from collecting vegetables from the wild, their cultivation in home gardens plays an important role towards household and nutritional security. Home gardens not only provide food, fodder, fuel, medicines, spices, construction material and income out they serve as genetic resources of plants. Hence, the home gardens play an important role for in-situ conservation of a wide range of plant genetic resources²³.

The phytochemical contents of the leafy vegetables serve as supplements for food and also have the potential to improve the health status of its users as a result of the presence of various compounds vital for good health. Their fibre content provides bulk in the diet and this helps to reduce the intake of starchy foods, enhances gastrointestinal function, prevents constipation and may thus reduce the incidence of metabolic diseases. However, with a combination of ethnobotanical, nutritional and biochemical research efforts, it is possible to improve the nutritional status of the rural poor by the use of native plants.

CONCLUSION:

“Food itself is medicine and medicine itself is food” is one of the basic principles of Siddha system of medicine. The plants taken by the irular tribe as food has various medicinal properties to cure diseases like cold, fever, mouth ulcer, diabetes. The plants used by them also contain cardioprotective, hepatoprotective, expectorant, stimulant, laxative, cooling, diuretic, aphrodisiac, rubefacient, demulscent, germicide, stomachic, alterative, diaphoretic, tonic and antibilous properties to heal various disorders.

This study was undertaken and aimed at recording the knowledge and usage of traditional plants, which grow in the kitchen garden and its association with their perception, cultural practice, gathering, processing and consumption of plants and their parts in diets in the Anaikatty area. The wild and cultivated food plants are of great importance to the Irulars. The traditional knowledge of the utility of these species which has been handed over from one generation to another faces extinction, due to urbanization and change in lifestyle. Therefore, it is important to document traditional knowledge before it vanishes.

The result of the present study provides a list of cultivated edible plants which plays an important role in supplying the edible plants to this ethnic community for their optimal and sustainable utilization. The ethnobotanical information gathered in this study may be considered as clues for prioritizing species for further critical scientific evaluation and bioprospection, leading to the development of value added products for human welfare. The underutilized food plant species are indispensible for food and nutrition security and will have a greater potential for income generation and environmental services. The Irulars are rich in traditional knowledge on food plants and their invaluable information on the local food consumption pattern make them to utilize these plant resources during adverse situation in future.

The underutilized food plants of Irulars required a detailed study regarding the nutritive value and other health factors and it is also requires attempts for developing nutraceuticals and other value added products from the research and development activities of various institutions. It is obvious that the underutilized food plants will ensure a more nutritive and healthy food security and efforts from the authorities also inevitable to promote the conservation and sustainable utilization of underutiltilized food plant species to maintain biodiversity and fight food insecurity in the country.

Table.1 List of edible plants used by the Irulas

S.No	Botanical name	Family	Local name	Parts used	Economic importance	Remarks
1	Barleria cristata L.	Acanthaceae	Kanakambaram	Flower	Hair do	-
2	Crossandra infundibuliformis (L.) Nees	Acanthaceae	Kanakambaram	Flower	Hair do	-
3	Alternanthera sessilis (L.) R.Br. ex DC.*	Amaranthaceae	Ponnankanni keerai	Whole plant	Vegetable	Cooking
4	Amaranthus polygamus L.	Amaranthaceae	Keerai	Whole plant	Vegetable	Cooking
5	Amaranthus roxburghianus H.W.Kung *	Amaranthaceae	Thandu keerai	Whole plant	Vegetable	Cooking
6	Amaranthus spinosus L. *	Amaranthaceae	Mullu keerai	Whole plant	Vegetable	Cooking
7	Amaranthus viridis L. *	Amaranthaceae	Paruppu keerai	Whole plant	Vegetable	Cooking
8	Celosia argentea L.	Amaranthaceae	Kozhi kondai	Flower	Ornamental	-
9	Mangifera indica L.*	Anacardiaceae	Mavu	Fruit	Edible/Medicinal	Cooking
10	Annona squamosa L.*	Annonaceae	Seetha	Fruit	Edible	-
11	Centella asiatica (L.) Urban*	Apiaceae	Vallarai	Leaf	Edible/Medicinal	Cooking
12	Coriandrum sativum L.*	Apiaceae	Kothamalli	Whole plant	Vegetable	-
13	Nerium oleander L.	Apocynaceae	Arali	Flower, Seed	Religious	-
14	Artemisia nilagirica (C.B.Clarke) Pamp.*	Asteraceae	Masipathri	Twig	Medicinal	-
15	Basella alba L.*	Basellaceae	Pasalai keerai	Twig	Vegetable	Cooking
16	Ceiba pentandra (L) Gaertn.*	Bombacaceae	Elavampanju	Fruit(Aril)	Aril raw eaten	-
17	Brassica juncea (L.) Czern.*	Brassicaceae	Kadugu	Seed	Flavour	Cooking
18	Tamarindus indica L. *	Caesalpiniaceae	Puli	Fruit	Vegetable	Cooking
19	Canna indica L.	Cannaceae	Kalvazhai	Flower	Ornamental	-
20	Carica papaya L.*	Caricaceae	Pappali	Fruit	Edible	-
21	Chenopodium album L.	Chenopodiaceae	Chakravarthi keerai	Leaf	Vegetable	Cooking
22	Ipomoea batatas (L.) Lam.	Convolvulaceae	Sarkaraivalli kizhangu	Tuber	Vegetable	Cooking
23	Coccinia grandis (L.) Voigt*	Cucurbitaceae	Kovai	Fruit	Vegetable	Cooking
24	Cucurbita maxima Duchesne	Cucurbitaceae	Poosanikai	Fruit	Vegetable	Cooking
25	Cucurbita pepo L.	Cucurbitaceae	Arasanikai	Fruit	Vegetable	Cooking
26	Luffa acutangula (L.) Roxb.*	Cucurbitaceae	Peerkangai	Fruit	Vegetable	Cooking
27	Momordica charantia L.*	Cucurbitaceae	Paagarkai	Fruit	Vegetable	Cooking
28	Mukia maderaspatana (L.) M.Roem. *	Cucurbitaceae	Musumusukkai	Leaf	Medicinal	-
29	Manihot esculenta Crantz	Euphorbiaceae	Maravalli kizhangu	Tuber	Vegetable	Cooking
30	Phyllanthus acidus (L.) Skeels	Euphorbiaceae	Arai nelli	Fruit	Edible	Making pickles
31	Phyllanthus emblica L.*	Euphorbiaceae	Nelli	Fruit	Edible/Medicinal	Making pickles
32	Ricinus communis L.*	Euphorbiaceae	Aamanakku	Leaf/Seed	Medicinal	Drug preparation
33	Lablab purpureus (L.) Sweet*	Fabaceae	Avaraikai	Fruit	Vegetable	Cooking
34	Sesbania grandiflora (L.) Pers.*	Fabaceae	Agathi	Leaf	Vegetable	Cooking
35	Plectranthus amboinicus (Lour.) Spreng.*	Lamiaceae	Karpuravalli	Leaf	Medicinal	Aromatic oil
36	Mentha arvensis L.*	Lamiaceae	Puthina	Leaf	Vegetable	Cooking
37	Ocimum basilicum L.	Lamiaceae	Thulasi	Leaf	Medicinal	-
38	Ocimum tenuiflorum L.	Lamiaceae	Thulasi	Whole plant	Medicinal	-
39	Allium cepa L.*	Liliaceae	Vengaayam	Bulb	Vegetable	Cooking
40	Lawsonia inermis L.*	Lythraceae	Maruthaani	Leaf/bark	Medicinal/Cosmetics	Hair dye
41	Abelmoschus esculentus (L.) Moench*	Malvaceae	Vendai	Fruit	Vegetable	Cooking
42	Gossypium arboreum L.*	Malvaceae	Paruthi	Fruit/Seed	Medicinal	-
43	Hibiscus rosa-sinensis L.*	Malvaceae	Sembarathi	Flower, stem	Edible/Medicinal	-
44	Azadirachta indica A.Juss.*	Meliaceae	Vembu	Whole plant	Medicinal	-
45	Musa paradisiaca L.	Musaceae	Vaazhai	Whole plant	Vegetable/Edible/Medicinal	-
46	Psidium guajava L.	Myrtaceae	Koyya	Fruit	Edible	-
47	Syzygium cumini (L.) Skeels*	Myrtaceae	Naaval	Fruit	Edible	-
48	Jasminum sambac (L.) Aiton*	Oleaceae	Malli	Flower	Hairdo/oil	-
49	Jasminum angustifolium (L.) Willd.	Oleaceae	Kaatu malligai	Flower	Medicinal/Cosmetics	-
50	Jasminum grandiflorum L.	Oleaceae	Malligai	Flower	Hair do	-
51	Oxalis corniculata L.*	Oxalidaceae	Puliyarai	Leaf	Vegetable	Cooking
52	Passiflora foetida L.	Passifloraceae	Sirupunnaikali	Leaf	Vegetable	Cooking
53	Piper nigrum L.*	Piperaceae	Milagu	Fruit	Medicinal/Spice	Cooking
54	Portulaca oleracea L	Portulaceae	Pasalai keerai	Leaf	Vegetable	Cooking
55	Portulaca quadrifida L.*	Portulaceae	Pasalai keerai	Leaf	Vegetable	Cooking
56	Ziziphus jujuba Mill.*	Rhamnaceae	Elanthai	Fruit	Edible	-
57	Rosa damascena Herrm.	Rosaceae	Roja	Flower	Edible	-
58	Coffea arabica L.*	Rubiaceae	Kaapi	Fruit	Beverage	-
59	Ixora coccinea L.	Rubiaceae	Idly poo	Flower	Ornamental	-
60	Citrus limon (L.) Osbeck*	Rutaceae	Elumichai	Fruit	Medicinal	Cooking/Pickles
61	Murraya koenigii (L.) Spreng.	Rutaceae	Karivepilai	Leaf, Fruit	Flavouring	Cooking
62	Capsicum annuum L.*	Solanaceae	Milagai	Fruit	Vegetable	Cooking
63	Capsicum frutescens L.*	Solanaceae	Milagai	Fruit	Vegetable	Cooking
64	Lycopersicon esculentum Mill.*	Solanaceae	Thakkali	Fruit	Vegetable	Cooking
65	Solanum melongena L.	Solanaceae	Katrikkai	Fruit	Vegetable	Cooking
66	Solanum nigrum L.*	Solanaceae	Manathakkali	Leaf, Fruit	Vegetable, Medicinal	Cooking
67	Solanum torvum Sw.*	Solanaceae	Chunda	Fruit	Vegetable, Medicinal	Cooking
68	Solanum americanum	Solanaceae	Manthakkali	Leaf, Fruit	Vegetable, Medicinal	Cooking
69	Solanum trilobatum L.*	Solanaceae	Thuduvalai	Leaf	Vegetable, Medicinal	Cooking
70	Vitex negundo L.*	Verbenaceae	Nochi	Seeds	Medicinal	-
71	Cissus quadrangularis L.*	Vitaceae	Pirandai	Young stem	Vegetable, Medicinal	Cooking
72	Zingiber officinale Roscoe*	Zingiberaceae	Inji	Rhizome	Flavouring, Medicinal	Cooking
73	Curcuma aromatica Salisb.*	Zingiberaceae	Kasthuri manjal	Rhizome	Cosmetics, Medicinal	-
74	Curcuma longa L*	Zingiberaceae	Manjal	Rhizome	Medicinal, Colouring agent	Cooking
75	Punica granatum L.	Punicaceae	Maadulam	Fruit	Medicinal, Edible	-

*Plants mentioned in Siddha literature to cure various ailments.