LEAFY VEGETABLES IN CHAPAI NAWABGANJ DISTRICT OF BANGLADESH FOCUSING ON MEDICINAL VALUE

Leafy vegetables in Chapai Nawabganj district of Bangladesh was studied from January to December 2019. A total of 111 species belonging to 59 genera under 30 families were recorded, out of which, 52.25% species were wild and 46.84% species were cultivated in this study. Status of occurrence has been recorded for proper conservation management and sustainable utilization of the taxa resulting in 81.98% to be common, 17.11% as rare and 0.90% are found as vulnerable in the study area. A total of 93 medicinal plants have been documented with their uses for the cure of more than 53 diseases. The study showed that the people of Chapai Nawabganj district use leafy vegetables to treat their diseases. Therefore, the documented leafy vegetables should be further investigated for their efficacy and safety to be integrated into conventional medicine. Further more these leafy vegetables need to be conserved for their sustainable utilization. Introduction Leaf vegetables, also called potherbs, greens, or leafy greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Nearly one thousand species of plants with edible leaves are known (Rashid, 1999). Leaf vegetables most often come from short-lived herbaceous plants, such as lettuce and spinach. Woody plants of various species (Moringa oleifera, Murraya koinigii, Morus alba, Toona cilliata etc.) also provide edible leaves (NRC, 2015). They constitute a major portion of our diet and play an important part in alleviating malnutrition. FAO (2012) has estimated that about 870 million people are chronically undernourished in the period 2010-12 representing 12.5% of the global population, or one in eight people. In order to arrest the undernourished situation, much attention has been paid on the exploitation and utilization of unusual plant materials for food (Kawatra et al., 2001). Indigenous (traditional) vegetables are best defined as species that are locally important for the sustainability of economics, human nutrition and health, and social systems. Over the last decade, many studies have shown that fresh vegetables constitute important functional food components by contributing vitamins, iron, folic acid, mineral, biologically active compounds and photosysthetic pigments (Kmiecik et al., 2001; Su et al., 2002; Kimura and Rodriguez-Amaya, 2003). Vegetables also contain antioxidants which offer protection against many chronic disease including heart disease and certain types of cancer (Saxena, 1999). In Bangladesh, people have a long heritage of taking leafy vegetables. However, very little attempt has been made to study the leafy vegetables of Bangladesh although they constitute a large proportion of the daily diet of the rural dweller of the country (Ali et al., 1977; Sarker and Corresponding author, E-mail: drrahmanahmm@ru.ac.bd 360 RAHMAN AND KHATUN Hossain, 2009; Hassan, 2010, Rahman et al., 2015; Khatun et al., 2013; Rashid 1999). Despite the importance of leafy vegetables in the present day human lives, no systematic work has been carried out in the study area to identify and document the plant species. In view of potential beneficial attributes of leafy vegetables, there is a need to explore, identify and document the leafy vegetables of Chapai Nawabganj district, Bangladesh. Materials and methods Study area Chapai Nawabganj is located on the north-western part of Bangladesh. It is a part of the Rajshahi Division and known for its special tone of local dialect. The north and west part of Chapai Nawabganj is bounded by Malda and Murshidabad district of India, east is by Naogaon District, and south-east is by Rajshahi District (BPC, 2001). Data collection The work is based on fresh materials collected during twenty three visits to Chapai Nawabganj distict, Bangladesh from January to December 2019 to cover the seasonal variations as well. The visits covered all types of habitats, particular river bank, slope, village grove, fruit gardens and roadsides of the study area. Medicinal information was obtained through semistructured interviews with knowledgeable people such as local ‘Kabiraj’(local herbal doctor) and elderly people. A total of 161 informants having an age rangeing from 21 to 69 years were interviewed using semi-structured interviewed method (Alexiades, 1996). Plant parts with either flower of fruits collected using traditional herbarium techniques to make voucher specimens for documentation. Plant identification Collected specimens have been critically examined, studied and identified. Identifications have been confirmed by consulting standard literatures (Hooker, 1877; Prain, 1903) and Herbarium of Rajshahi University (HRU). Nomenclature has been updated following recent literature (Ahmed et al., 2008-2009; Huq, 1986, and Pasha and Uddin, 2013). Results and Discussion Documentation of leafy vegetable taxa in Chapai Nawabganj district of Bangladesh was investigated. Out of 111 species, 106 belong to angiosperms, and 5 to pteridophytes. Among the angiospermic taxa Magnoliopsida is represented by 96 taxa and Liliopsida is represented by 10 taxa (Table 1). Distribution of leafy vegetables in the families shows variation. Cucurbitaceae is the dominant family represented by 16 species, followed by Amaranthaceae (13 species), Brassicaceae (9 species), Fabaceae (8 species), Araceae (8 species), Solanaceae (7 species), Convolvulaceae (7 species), Malvaceae (4 species) and Polygonaceae (4 species) (Table 1; Fig. 3). A single species is represented by 9 families while 2 to 3 species is represented by 12 families. Out of recorded species, 52.25% species were wild and 46.84% species were cultivated in the study area (Fig. 2). Status of occurrence has been recorded for proper conservation management and sustainable utilization of the taxa resulting in 81.98%) to be common, 17.11% as rare and 0.90% are found as vulnerable in the study area (Fig. 1). The collected information is comparable with the result of other studies in Bangladesh and abroad. In Bangladesh, 186 species were recorded as leafy vegetables (Khatun et al, 2013). A total of 24 species belonging to 22 genera and 16 families were collected and identified in Bogra district (Rahman et al, 2015). Narayanan and Kumar (2007) in India recorded a total of 102 wild edible leaves in Paniya, Kattunaikka and Kuruma tribes, but families consume 88, 43 and 21, LEAFY VEGETABLES IN CHAPAI NAWABGANJ DISTRICT 361 Table 1. Diversity of leafy vegetables in Chapai Nawabganj district, Bangladesh. Scientific name Bangla name Family Status of occurrence Flowering time Voucher number Acalypha indica L. Muktajhuri Euphorbiaceae Common Mar-Oct MK 91 Amaranthus blitum L. Notiya shak Amaranthaceae Common Jan-Dec MK 29 Amaranthus gangeticus L. Lal shak Amaranthaceae Common Jun-Aug MK 124 Amaranthus lividus Roxb. Gobranotey Amaranthaceae Common Jan-Dec MK 31 Amaranthus oleracea L. Data shak Amaranthaceae Common Jan-Dec MK 122 Amaranthus polygonoides L. Notey shak Amaranthaceae Common Jan-Dec MK 33 Amaranthus spinosus L. Katanotey Amaranthaceae Common Jan-Dec MK 120 Amaranthus tricolor L. Lal shak Amaranthaceae Common Jan-Dec MK 35 Amaranthus viridis L. Notey shak Amaranthaceae Common Jan-Dec MK 118 Alternanthera sessilis (L.) R. Br. Sachishak Amaranthaceae Common MayOct MK 37 Alternanthera philoxeroides (Mart.) Griseb. Malancha Amaranthaceae Common Mar-Jun MK 116 Alternanthera bettzickiana L. Malancha Amaranthaceae Rare Mar-Jun MK 39 Azadirachta indica A. Juss. Nimpata Meliaceae Common Mar-Apr MK 93 Alocasia indica Schott. Mankochu Araceae Common Aug-Oct MK 117 Amorphophalus bulbifer (Roxb.) Blume Olkochu pata Araceae Common JulAug MK 36 Allium cepa L. Piaj. Liliaceae Common Feb-Apr MK 125 Allium sativum L. Rasun. Liliaceae Common Feb-Apr MK 28 Angiopteris evecta (Forst.) Hoffm. Dhekishak Angiopteridaceae Rare Jan-Dec MK 127 Argemone mexicana L. Sialkata Papaveraceae Common Jan-Dec MK 133 Basella alba L. Puishak Basellaceae Common Nov-Feb MK 110 Benincasa hispida (Thunb.) Cogn. Chalkumra. Cucurbitaceae Common May-Sep MK 57 Boerhaavia repens L. Punarnava Nyctaginaceae Common Jan-Dec MK 130 Brassica alba Hook. Sada sorisha shak Brassicaceae Common MarMay MK 80 Brassica campestris Roxb. Sorisha shak Brassicaceae Common MarMay MK 75 Brassica juncea L. Rai sorisha Brassicaceae Common MarMay MK 78 Brassica napus L. Kalo Sarisha Brassicaceae Common MarMay MK 77 Brassica oleracea L. var. botrydis Fulkopi Brassicaceae Common Dec-Feb MK 76 Brassica oleracea L. var. capitata Badhakopi Brassicaceae Common Dec-Feb MK 79 Brassica oleracea L. var. gangyloides Olkopi Brassicaceae Common Dec-Feb MK 74


Introduction
Leaf vegetables, also called potherbs, greens, or leafy greens, are plant leaves eaten as a vegetable, sometimes accompanied by tender petioles and shoots. Nearly one thousand species of plants with edible leaves are known (Rashid, 1999). Leaf vegetables most often come from short-lived herbaceous plants, such as lettuce and spinach. Woody plants of various species (Moringa oleifera, Murraya koinigii, Morus alba, Toona cilliata etc.) also provide edible leaves (NRC, 2015). They constitute a major portion of our diet and play an important part in alleviating malnutrition. FAO (2012) has estimated that about 870 million people are chronically undernourished in the period 2010-12 representing 12.5% of the global population, or one in eight people. In order to arrest the undernourished situation, much attention has been paid on the exploitation and utilization of unusual plant materials for food (Kawatra et al., 2001). Indigenous (traditional) vegetables are best defined as species that are locally important for the sustainability of economics, human nutrition and health, and social systems. Over the last decade, many studies have shown that fresh vegetables constitute important functional food components by contributing vitamins, iron, folic acid, mineral, biologically active compounds and photosysthetic pigments Su et al., 2002;Kimura and Rodriguez-Amaya, 2003). Vegetables also contain antioxidants which offer protection against many chronic disease including heart disease and certain types of cancer (Saxena, 1999).
In Bangladesh, people have a long heritage of taking leafy vegetables. However, very little attempt has been made to study the leafy vegetables of Bangladesh although they constitute a large proportion of the daily diet of the rural dweller of the country (Ali et al., 1977;Sarker and Hossain, 2009;Hassan, 2010, Rahman et al., 2015Khatun et al., 2013;Rashid 1999). Despite the importance of leafy vegetables in the present day human lives, no systematic work has been carried out in the study area to identify and document the plant species. In view of potential beneficial attributes of leafy vegetables, there is a need to explore, identify and document the leafy vegetables of Chapai Nawabganj district, Bangladesh.

Study area
Chapai Nawabganj is located on the north-western part of Bangladesh. It is a part of the Rajshahi Division and known for its special tone of local dialect. The north and west part of Chapai Nawabganj is bounded by Malda and Murshidabad district of India, east is by Naogaon District, and south-east is by Rajshahi District (BPC, 2001).

Data collection
The work is based on fresh materials collected during twenty three visits to Chapai Nawabganj distict, Bangladesh from January to December 2019 to cover the seasonal variations as well. The visits covered all types of habitats, particular river bank, slope, village grove, fruit gardens and roadsides of the study area. Medicinal information was obtained through semistructured interviews with knowledgeable people such as local 'Kabiraj'(local herbal doctor) and elderly people. A total of 161 informants having an age rangeing from 21 to 69 years were interviewed using semi-structured interviewed method (Alexiades, 1996). Plant parts with either flower of fruits collected using traditional herbarium techniques to make voucher specimens for documentation.

Results and Discussion
Documentation of leafy vegetable taxa in Chapai Nawabganj district of Bangladesh was investigated. Out of 111 species, 106 belong to angiosperms, and 5 to pteridophytes. Among the angiospermic taxa Magnoliopsida is represented by 96 taxa and Liliopsida is represented by 10 taxa (Table 1). Distribution of leafy vegetables in the families shows variation. Cucurbitaceae is the dominant family represented by 16 species, followed by Amaranthaceae (13 species), Brassicaceae (9 species), Fabaceae (8 species), Araceae (8 species), Solanaceae (7 species), Convolvulaceae (7 species), Malvaceae (4 species) and Polygonaceae (4 species) (Table 1; Fig. 3). A single species is represented by 9 families while 2 to 3 species is represented by 12 families. Out of recorded species, 52.25% species were wild and 46.84% species were cultivated in the study area (Fig. 2). Status of occurrence has been recorded for proper conservation management and sustainable utilization of the taxa resulting in 81.98%) to be common, 17.11% as rare and 0.90% are found as vulnerable in the study area (Fig. 1).
The collected information is comparable with the result of other studies in Bangladesh and abroad. In Bangladesh, 186 species were recorded as leafy vegetables (Khatun et al, 2013). A total of 24 species belonging to 22 genera and 16 families were collected and identified in Bogra district (Rahman et al, 2015). Narayanan and Kumar (2007) in India recorded a total of 102 wild edible leaves in Paniya, Kattunaikka and Kuruma tribes, but families consume 88, 43 and 21,  (Abukutsa and Onyango, 2005). Further, in Andhra Pradesh, India; Reddy et al. (2007) report 69 families of wild food plants, where four families: Amaranthaceae (11 species); Rubiaceae (9 species); Euphorbiaceae (8 species) and Papilionaceae (7 species); have a high number of species, with Amaranthaceae family having the highest number of species. Fleuret (1979) recorded more than 15 species of wild leafy vegetables in her study in the Lushoto district, Tanzania. Woodcook's (1995) studied on indigenous knowledge and forest use in the East Usambaras in Tanzania documents 25 wild leafy vegetable species. So far the information available, no published data recorded on the leafy vegetables in Chapai Nawabganj district, Bangladesh. The present study will also help in identifying the important leafy vegetables for future reference. Present study demonstrated that there is an urgent need for documentation of traditional knowledge related to the intangible cultural heritage concerning wild vegetables are utilized. The utilization and cultivation of these vegetables should be promoted to maintain the dietary needs of the household in Chapai Nawabganj district. The study can provide a baseline data that may be helpful for prioritization of conservation through sustainable use and management of the resources.

Medicinally Important Leafy Vegetables
Out of 111 species, 93 medicinal plants have been documented with their uses for the cure of more than 53 diseases. The medicinal plants are used by the local people to cure many the diseases, especially for anemia, asthma, burning sensation, blood diseases, bronchitis, cough, chicken pox, constipation, dysentery, diarrhea, diabetes, eczema, fever, headache, itches, jaundice, menstrual disease, paralysis, piles, sex problems, skin diseases, snake-bite, toothache, worm, wound etc. Different plant parts of different species are used as medicine for treating various diseases where;-leaf of 65.76%, fruit of 17.11%, root of 9.90%, stem of 1.80%, seed of 19.81%, bulb of 1.80%, Corm of 2.70%, Flower of 2.70% and whole plant of 18.01% species were used as medicine (Fig. 4). The survey recorded 53 categories of uses of 93 medicinal leafy vegetables ( Table 2). Out of 53 categories of ailments, Dysentery, fever, skin disease, cough, inflammation,    constipation, gonorrhea, piles and rheumatism was dominant diseases in the study area (Fig. 5). This finding suggests that the leafy vegetables may possibly contain other phytochemical constituents which need to be investigated in future studies. This finding of common medicinal plant families in this study is in agreement with Anisuzzaman et al (2007); Ghani (2003); Khan (1998), Choudhury and Rahmatullah (2012), Faruque and Uddin (2014), Uddin and Hassan (2014), Uddin et al., (2015), and Yusuf et.al (2006). The present study revealed that medicinal plants still play an important in the primary health care of the rural communities. The information gathered from the local traditional healers are useful for further researchers in the field of ethnobotany, taxonomy and development of new drug from natural resources.