ABSTRACT

The world is suffering due to the double burden of malnutrition i.e., under-nourished and over-nourished which is increasing day by day. Lack of dietary diversity and changing climatic scenarios are paving the way for this severe problem. There could be many solutions to address this chronic problem. However, using locally grown indigenous fruit species could be the cheapest and sustainable solution to tackle these issues locally as well as globally. To understand the existing barriers which are hindering to unlock the full potential of these fruit species, the present study was designed. To explore the ethno-horticultural and physico-chemical potential of some selected indigenous fruits such as persimmon, date plum, apple, pear, autumn olive, black raspberry, yellow raspberry, quince, barberry, apricot, fig, wood land strawberry, wild pomegranate, black mulberry, and plum were collected from different villages of District Poonch and analysed for various parameters. Ethno-horticultural information was gathered and documented during a survey conducted in this area while physico-chemical characterization was done through analytical studies. Samples were analysed for physico-chemical parameters such as, fruit weight, total soluble solids, titratable acidity, vitamin C, pH, total antioxidants, total flavonoids, and total phenols. The physico-chemical results showed that there is a huge potential of these fruit crops to be used locally and at national level. Further, small scale industry should be established to develop value added products.

INTRODUCTION

The knowledge about ethno-horticultural and physico-chemical composition of indigenous plant species is considered an important source of commercialization for those plants (Silva et al., 2017). The physico-nutritional elements are the main source of nutrients and contribute widely to human nutrition (Maqbool et al., 2019; Hardisson et al., 2001), which help to prevent incidence of various diseases and maintain human health (Hooshmand and Arjimani, 2009). In this regard fruits and vegetables have an important role as they are the main source of antioxidants and other functional and nutritional elements. They contain various organic acids, carbohydrates fibres, aromatic compounds, tannins, and enzymes. Each of these compounds is considered essential for taste and nutritional value of fruits (Ertekin et al., 2006). Apart from these elementary food contents, fruits are rich source of phenolics, relatively high anthocyanins and antioxidants (Cevallos-Casals and Cisneros-Zevallos, 2004).

It has been reported by many researchers that fruits from different cultivars and wild relatives vary in their physico-chemical properties and sensory characteristics (Ajenifujah-Solebo and Aina, 2011; Lozano et al., 2009; Gil et al., 2002). This variation is always linked with variety, environmental conditions, and growing practises (Vursavus et al., 2006). Further, many scientists also reported that there were different values of phenolic contents, total flavonoids, total anthocyanins, and antioxidants among different cultivars of different fruits (Kristl et al., 2011; Cevallos-Casals et al., 2006; Rupasinghe et al., 2006; Gil et al., 2002).

Indigenous fruit species are generally not known as cash crops due to their unexplored and unutilized market potential. They play an important role in most of the rural communities as their farming practices as well as lifestyle strategies are dependent on these indigenous fruit species (Mitra et al., 2008). The reason for not recognising them as cash crops is that they are mostly planted alongside major crops as subsistence crops (FAO, 2009). In most of the cases, these indigenous fruit species are locally grown and are well adapted to the environmental and climatic conditions which is a huge advantage for farmers who can grow them on a relatively low cost (Jaenicke and Lengkeek, 2008; WHO, 2002). Therefore, they are designed to suit local conditions and for this reason research into these species and the farming systems in which they are produced has the potential to support both food security and nutritional wellbeing of growers.

The area of Azad Jammu and Kashmir is highly diverse in terms of natural flora and fauna. This genetic diversity is because of its geographic location, as it is located between the centre of China and Caucasus Mountains (Nisar et al., 2015). This mountainous area possesses varied climatic conditions ranging from subtropical to temperate. Many temperate fruits are grown in this area e.g., pear, plum, apple, walnut etc. and a huge genetic diversity is found in these crops that might be because of natural seed-based proliferations, hybridization, or mutation (Ahmed et al., 2009). The mountainous region of Azad Jammu and Kashmir holds many indigenous fruit plantations. Along with number of different fruit species which consists of wild natives, a huge plantation of traditional varieties also exists (Ahmed et al., 2009). Although fruits are considered an excellent source of vitamins and dietary fibres, however, producers prefer high yielding, disease, and insect-pest resistant varieties. Whereas consumer demands for good taste, size, shape, and quality of fruit (Lace and Lacis, 2015).

However, the major drawback in commercial utilization of these indigenous fruit species grown in this area is the lack of nutritional importance. Many wild fruit species exists in this area are not yet characterized in terms of their ethno-botanical, biochemical, nutritional, and functional ingredients. Furthermore, no efforts have been made to exploit these indigenous fruit species for different uses. Therefore, the characterization of these indigenous fruit species is necessary for their nutritional uses. Thus, in this regard the present work has been designed to characterize ethno-horticultural and physico-chemical properties of different fruit species grown in District Poonch of Azad Jammu and Kashmir.

MATERIALS AND METHODS

Plant material

Fully mature fruits of selected indigenous fruit species were harvested from private orchards located at District Poonch, Azad Jammu and Kashmir (Fig. 1). Healthy fruits having uniform size, shape and free from all external impurities were transported to the Laboratory of Department of Horticulture, University of Poonch Rawalakot for further analysis.

Figure 1: Map of Azad Jammu and Kashmir and description of study site – District Poonch.

Ethno-horticultural survey

An initial survey of selected area was conducted to identify indigenous fruits and then some important ethno-horticultural characteristics such as (English name, local name, botanical name, family name, and traditional uses) of selected indigenous fruit species (persimmon, date plum, apple, pear, autumn olive, black raspberry, yellow raspberry, quince, barberry, apricot, fig, wood land strawberry, wild pomegranate, black mulberry, and plum) were documented during this study.

Physico-chemical characteristics

Fruit weight

Digital balance (Model: Shimadzu A x 200, Japan) was used to determine fruit weight.

Total soluble solids

TSS was quantified by using hand refractometer (Kyoto Company, Japan). Briefly, two drops of juice from each fruit were placed on the glass of refractometer. Results were then articulated in °Brix. Before analysis, refractometer was calibrated against sucrose (Ali et al., 2014).

Titratable acidity

TA in selected fruits was measured by AOAC (2012) method No. 9720.21. Fruit pulp (5 g) was taken from each sample, mixed with deionized water (20 ml), and filtered to obtain the extract. For titration 5ml aliquot was taken and titrated against standard 0.1 N sodium hydroxide using few drops of phenolphthalein indicator till the change of colour to light pink as an end point. Readings were recorded as percent TA using the following formula.

TA (%) = 0.1 x equivalent weight of dominant acid x Normality of NaOH x titre value / Weight of sample

Vitamin C

Assessment of vitamin C in each sample of selected fruits was determined by method as reported in AOAC (2012) (Method No. 967.22). 2,6-dichlorophenol indophenol dye was used to measure vitamin C. Extracted sample (5 ml) was taken in 100 ml of conical flask and 5 ml of meta-phosphoric acid solution (4 %) was also added in this flask and this mixture was titrated with dye until light pink colour appeared as an end point.

Vitamin C (mg/100 g) = F × T × 100 / S × D

Where, F = Standardization factor = ml of ascorbic acid / ml of pigment used

T = ml of pigment used for sample

S = ml of diluted sample taken for titration

D = ml of sample taken for dilution

pH

Digital pH meter (Model: WTW 82362 Inolab, Germany) was used to determine pH of fruit juice.

Total antioxidants (Activity of mg FeSO₄ g^-1 FW)

Total antioxidants activity in selected fruits was measured by using Ferric Reducing Antioxidant Power (FRAP) assay. Reaction mixture contained 40 µl of fruit juice and 3 ml of FRAP reagent followed by incubation for 4 min at 37 °C. Absorbance was recorded at 593 nm, and the results were expressed as ferric reducing activity equivalent to1 mg FeSO₄ g^-1 of fresh fruit weight. FRAP reagent consisted of 25 ml of 0.03 mM acetate buffer (pH 3.6), 2.5 ml of 20 mM FeCl₃ and 2.5 ml of 10 mM 2,4,6- Tripyridyl-s-triazine (TPTZ) solution dissolved in 40 mM HCl.

Total flavonoids

Total flavonoids were measured by using the spectrophotometric method. Fruit samples (0.5 mg) were ground by using mortar and pestle followed by mixing with 2.0 % methanolic AlCl₃.6H₂O (1.5 ml) in sealed tubes and kept in the dark for 15 min. A UV-vis spectrophotometer (UV 4000 Spectrophotometer, Germany) was used for measuring absorbance at 430 nm. Results were expressed as mmol of quercetin 100 g^-1 fresh fruit weight.

Total phenols

Total phenols were measured spectrophotometrically by using Folin Ciocalteau (FC) reagent. Fruit juice (0.1 ml) was mixed with 7.0 % sodium carbonate (1.5 ml) and FC (0.5 ml). Purified water was added to make volume of mixture up to 10 ml. Reaction mixture was incubated for 2 hours at 40°C. Absorbance was recorded at 750 nm by using a UV–vis spectrophotometer (UV 4000 Spectrophotometer, Germany). Results were expressed as mg gallic acid 100 g^-1 fresh fruit weight.

RESULTS AND DISCUSSION

Ethno-horticultural characteristics of selected indigenous fruits species

It was observed during a survey, that these indigenous fruits species are being used traditionally for therapeutics of minor ailments which shows the importance of these crops in local communities (Table 1). It was also observed that these indigenous fruits species are not only nutritious but also possess great potential. However, still there are considerable barriers which are causing the main hindrance in unlocking the full potential of these species. One of the most important barriers is that these fruits have improper supply chain system and are mostly traded locally in nearby markets. Secondly, a limited research has been conducted to explore the actual potential of these fruit species. Consequently, a limited information and knowledge was available regarding these species which has caused a lack of awareness among communities about the real significance and potential of these indigenous crops.

Table 1: Ethno-botanical information and traditional uses of selected indigenous fruit species from District Poonch.

In terms of physico-chemical characteristics all the selected indigenous fruit species showed appreciable levels of fruit weight, total soluble solids, titratable acidity, vitamin C and pH. Further, fruits were also found to be a good source of total antioxidants, total flavonoids, and total phenols as well (Table 2).

Table 2: Physico-chemical characteristics of selected indigenous fruit species from District Poonch.

All the indigenous fruits showed appreciated levels of fruit weight. Fruit weight of persimmon was recorded (160.4 g), for date plum (12.14 g), apple (green) (112.5 g), apple (red) (115.4 g). In case of different pear fruits, fruit weight ranged from 39.64 g to 146.9 g. Desi pear fruits showed the lowest fruit weight (39.64g) while the highest fruit weight was observed in white pear (146.9g). Similarly other pears such as small pear (95.5 g), European pear (125.0 g), black pear (127.8 g) and local pear (44.8 g) showed different fruit weight. Autumn olive is a small fruit and hence its weight was measured for ten fruits which was about 1.55 g/10 fruits. Between two raspberries, black raspberry fruits had more weight (6.63 g) as compared with yellow raspberry (6.13 g). Quince fruit showed about 150.8 g, while barberry had 9.80 g/10 fruits and apricot fruits had 54.23 g fruit weight. Among figs, cluster fig had the highest fruit weight (24.26 g), while common fig had (20.76 g) and the lowest fruit weight was recorded in wild fig (6.24 g). Fruits of wood land strawberry showed (8.23 g) fruit weight, while wild pomegranate had (44.64 g) and black mulberry fruits had (7.78 g) fruit weight. Between two plums, plum (aloocha) showed 56.17 g fruit weight while desi plum showed 22.73 g fruit weight. The difference in fruit weight of these local fruits even within the same family was observed which could be due to marked differences in size of fruits.

In case of total soluble solids, all the indigenous fruits showed appreciated levels of total soluble solids. Total soluble solids in persimmon were recorded as (15.30 °Brix), in date plum (15.32 °Brix), apple (green) had (12.32 °Brix) while apple (red) had (13.26 °Brix). Among pears, European pear (9.86 °Brix) had the maximum total soluble solids followed by black pear (8.02 °Brix), white pear (8.73 °Brix), small pear (7.83 °Brix), local pear (6.14 °Brix) while desi pear (5.24 °Brix) showed the minimum amount of total soluble solids. In case of autumn olive total soluble solids were recorded very high (19.14 °Brix). In raspberries, yellow raspberry (11.67 °Brix) showed more total soluble solids as compared with black raspberry (10.67 °Brix). In quince total soluble solids were recorded as 14.0 °Brix, in barberry (12.45 °Brix), and in apricot (16.13 °Brix). Among figs, cluster fig (15.46 °Brix) had the highest amount of total soluble solids followed by common fig (14.20°Brix) while the least amount of total soluble solids was recorded in wild fig (13.24 °Brix). Total soluble solids in wood land strawberry (14.12 °Brix) were recorded very high, while in wild pomegranate it was (8.67 °Brix) and in black mulberry total soluble solids were found as 12.26 °Brix. Between two plums, a higher value of total soluble solids was recorded in plum (aloocha) (13.23 °Brix) as compared with desi plum (12.45 °Brix). Similar results were obtained by Erturk et al. (2009), where they found that plum with red colour (14.78 %) had higher amount of total soluble solids when compared with dark purple colour plum fruit (11.98 %). The difference in total soluble solids of these local fruits even within the same family was observed which could be due to marked differences in water contents of fruits (Vilhena et al., 2020).

Appreciated amount of total titratable acidity was found in all the indigenous fruits. Total titratable acidity in persimmon fruits was recorded as 0.07 %, in date plum (0.49 %), in apple (green) (0.84 %) and in apple (red) (0.87 %). Among pears, small pear (0.59 %) and European pear (0.59 %) had higher and similar amount of total titratable acidity which was followed by white pear (0.53 %), black pear (0.49 %) and local pear (0.32 %), while the lowest amount of total titratable acidity was recorded in desi pear (0.31 %). In case of autumn olive total titratable acidity was found as 0.56 %. In raspberries, yellow raspberry (2.40 %) had more total titratable acidity value as compared with black raspberry (2.06 %). In quince total titratable acidity was recorded as (0.43 %), in barberry (0.67 %) and in apricot (0.21 %). Among figs, cluster fig (0.33 %) had the highest amount of total titratable acidity which was followed by common fig (0.26 %), while the lowest amount of total titratable acidity was found in wild fig (0.23 %). In wood land strawberry it was 0.34 %, in wild pomegranate (0.89 %), and in black mulberry it was (0.45 %). In case of plums, desi plum (0.43 %) had more total titratable acidity as compared with plum (aloocha) (0.25 %). However, lower values of titratable acidity were observed in fruits of present study as higher values were reported earlier by Erturk et el. (2009) in red skinned plum (4.99 %) and in dark purple skinned plum (3.89 %), which indicates that the fruits used in present study were less acidic.

In case of vitamin C all the indigenous fruits showed good levels of vitamin C. In persimmon good amount of vitamin C content were recorded (4.62 mg/100 g). In date plum (7.62 mg/100 g), apple (green) (8.66 mg/100 g) and apple (red) (8.41 mg/100 g) appreciated amount of vitamin C content was noted. Among pears, white pear (7.33 mg/100 g) showed the highest levels of vitamin C content which were followed by black pear (7.20 mg/100 g), small pear (5.69 mg/100 g), local pear (5.67 mg/100 g) and European pear (5.34 mg/100 g), while the lowest value was recorded in desi pear (4.25 mg/100 g). In case of autumn olive vitamin C content were found as 8.43 mg/100 g. In raspberries, black raspberry (9.33 mg/100 g) had more vitamin C content as compared with yellow raspberry (8.00 mg/100 g). In quince vitamin C content were recorded as 8.40 mg/100 g, in barberry (8.71 mg/100 g) and in apricot (7.76 mg/100 g). Among figs, wild fig (8.15 mg/100 g) had the highest levels of vitamin C content which were followed by common fig (7.22 mg/100 g), while the lowest amount was recorded in cluster fig (4.76 mg/100 g). In wood land strawberry it was noted as 8.67 mg/100 g, in wild pomegranate (8.34 mg/100 g), and in black mulberry (7.56 mg/100 g). In plums, plum (aloocha) (7.78 mg/100 g) had more vitamin C content as compared with desi plum (7.12 mg/100 g). Similar results were reported by Gil et al. (2002) where they observed vitamin C content in the range of 3-10 mg/100 g in five fresh plum cultivars.

The pH values in all the indigenous fruits showed good levels. In persimmon pH was noted as 6.20, in date plum (4.56), in apple (green) (3.99) and in apple (red) it was recorded as 3.63. In case of pears, the highest value of pH was noted in European pear (5.14) which was equal to desi pear (5.14) and followed by local pear (4.98), small pear (4.75) and white pear (4.68), while the lowest amount of pH was noted in black pear (4.63). In autumn olive pH was found as 3.64. In raspberries, yellow raspberry (3.77) had more pH than black raspberry (3.74). In quince it was 3.43, in barberry (4.32) and in apricot it was (4.56). Among figs, cluster fig (6.10) had the highest value of pH which was followed by wild fig (5.40), while the lowest value was noted in common fig (4.24). In wood land strawberry it was recorded as 4.34, in wild pomegranate (3.78) and in black mulberry (4.12). In case of plums, desi plum (3.52) had more pH value as compared with plum (aloocha) (3.36). Almost similar values of pH were reported earlier by Erturk et al. (2009) where they found that dark purple and red skinned plum fruits had 3.13 and 3.70 pH, respectively.

All the indigenous fruits showed good amount of total antioxidants. In persimmon total antioxidants were noted as 11.76 mg FeSO₄ g^-1 FW, in date plum (12.34 mg FeSO₄ g^-1 FW), in apple (green) (12.14 mg FeSO₄ g^-1 FW) and in apple (red) (15.19 mg FeSO₄ g^-1 FW). Among pears, white pear (17.64 mg FeSO₄ g^-1 FW) had the highest amount of total antioxidants which was followed by European pear (16.79 mg FeSO₄ g^-1 FW), black pear (14.20 mg FeSO₄ g^-1 FW), small pear (11.43 mg FeSO₄ g^-1 FW) and local pear (6.13 mg FeSO₄ g^-1 FW), while the lowest total antioxidants were recorded in desi pear (6.10 mg FeSO₄ g^-1 FW). In autumn olive total antioxidants were observed as 13.31 mg FeSO₄ g^-1 FW. In case of raspberries, black raspberry (14.34 mg FeSO₄ g^-1 FW) had more total antioxidants as compared with yellow raspberry (14.10 mg FeSO₄ g^-1 FW). In quince total antioxidants were noted as 11.26 mg FeSO₄ g^-1 FW, in barberry (12.45 mg FeSO₄ g^-1 FW) and in apricot (16.78 mg FeSO₄ g^-1 FW). Among figs, common fig (16.23 mg FeSO₄ g^-1 FW) had the highest level of total antioxidants which was followed by wild fig (15.45 mg FeSO₄ g^-1 FW), while the lowest level was noted in cluster fig (14.78 mg FeSO₄ g^-1 FW). In wood land strawberry it was recorded as 13.24 mg FeSO₄ g^-1 FW, in wild pomegranate (13.23 mg FeSO₄ g^-1 FW) and in black mulberry (12.65 mg FeSO₄ g^-1 FW). In case of plums, plum (aloocha) (17.80 mg FeSO₄ g^-1 FW) had more total antioxidants as compared with desi plum (15.70 mg FeSO₄ g^-1 FW). This is a fact that antioxidants vary from species to species and with difference in climatic conditions (Scalzo et al., 2005). Fruits are considered a good source of natural antioxidants and hence many studies have been conducted to exploit their remarkable antioxidant potential (Scalzo et al., 2005). In the present study, antioxidant activity was due to presence of high vitamin C, total flavonoids, and total phenols in all the indigenous fruits. Variation in genetic makeup for antioxidant activity also exists, depending upon vitamin C, total flavonoids, and total phenols in fruits. In a previous study by Gil et al. (2002), it has been reported that a strong correlation was observed among antioxidants, total flavonoids and total phenols in various fruits including plums, peaches, and nectarines.

Total flavonoids in all the indigenous fruits were recorded in appreciable amount. In persimmon total flavonoids were noted as 3.23 mmol of quercetin 100 g^-1 FW, in date plum (4.21 mmol of quercetin 100 g^-1 FW), in apple (green) (3.06 mmol of quercetin 100 g^-1 FW) and in apple (red) (2.84 mmol of quercetin 100 g^-1 FW). Among pears, European pear (2.38 mmol of quercetin 100 g^-1 FW) had the highest level of total flavonoids which was followed by white pear (2.31 mmol of quercetin 100 g^-1 FW), black pear (1.98 mmol of quercetin 100 g^-1 FW), small pear (1.66 mmol of quercetin 100 g^-1 FW) and desi pear (1.10 mmol of quercetin 100 g^-1 FW), while the lowest level was observed in local pear (0.98 mmol of quercetin 100 g^-1 FW). In case of autumn olive total flavonoids were noted as 2.18 mmol of quercetin 100 g^-1 FW. In raspberries, black raspberry (3.80 mmol of quercetin 100 g^-1 FW) had more total flavonoids as compared with yellow raspberry (3.67 mmol of quercetin 100 g^-1 FW). In quince it was noted as 2.23 mmol of quercetin 100 g^-1 FW, in barberry (3.17 mmol of quercetin 100 g^-1 FW) and in apricot (2.98 mmol of quercetin 100 g^-1 FW). In case of figs, common fig (4.27 mmol of quercetin 100 g^-1 FW), had the maximum value of total flavonoids which was followed by wild fig (3.24 mmol of quercetin 100 g^-1 FW), while the minimum value was noted in cluster fig (3.21 mmol of quercetin 100 g^-1 FW). In wood land strawberry it was recorded as 4.23 mmol of quercetin 100 g^-1 FW, in wild pomegranate (4.12 mmol of quercetin 100 g^-1 FW) and in black mulberry (4.54 mmol of quercetin 100 g^-1 FW). In case of plums, plum (aloocha) (2.68 mmol of quercetin 100 g^-1 FW) had more total flavonoids as compared with desi plum (2.11 mmol of quercetin 100 g^-1 FW).

Good amount of total phenols was recorded in all the indigenous fruits. In persimmon total phenols were noted as 10.32 mg gallic acid per 100 g, in date plum (10.45 mg gallic acid per 100 g), in apple (green) (12.84 mg gallic acid per 100 g) and in apple (red) (11.24 mg gallic acid per 100 g). In case of pears, the highest levels of total phenols were noted in European pear (15.83 mg gallic acid per 100 g) which were followed by white pear (14.36 mg gallic acid per 100 g), black pear (13.56 mg gallic acid per 100 g), small pear (10.64 mg gallic acid per 100 g), and desi pear (4.87 mg gallic acid per 100 g), while the lowest levels were recorded in local pear (4.81 mg gallic acid per 100 g). In autumn olive it was noted as 13.23 mg gallic acid per 100 g. In case of raspberries, yellow raspberry (13.56 mg gallic acid per 100 g) had more total phenols as compared with black raspberry (12.72 mg gallic acid per 100 g). In quince it was noted as 10.42 mg gallic acid per 100 g, in barberry (15.56 mg gallic acid per 100 g) and in apricot (4.86 mg gallic acid per 100 g). Among figs, common fig (13.26 mg gallic acid per 100 g) had the highest amount of total phenols which was followed by wild fig (11.12 mg gallic acid per 100 g), while the lowest amount was noted in cluster fig (10.36 mg gallic acid per 100 g). In wood land strawberry it was noted as 11.28 mg gallic acid per 100 g, in wild pomegranate (12.19 mg gallic acid per 100 g) and in black mulberry (10.98 mg gallic acid per 100 g). In case of plums, plum (aloocha) (5.10 mg gallic acid per 100 g) had more total phenols as compared with desi plum (3.34 mg gallic acid per 100 g).

A difference in total flavonoids, total phenols and total antioxidants was also recorded in all the indigenous fruits under study. Quinic acid, rutin, iso-quercitrin, chlorogenic acids etc. are predominant markers for fruit nutritional quality and these different acids are responsible for the formation of flavonoids complex (Liaudanskas et al., 2020). Total phenolic contents are the essential components in various fruits and are well known due to their health-related properties. Phenolic compounds are also responsible for contribution of colour in fruits (Nisar et al., 2015). Phenolic contents help to protect low density lipoprotein from oxidation and thus they are considered to avoid age related diseases (Fang et al., 2002). The amount of phenolic contents varies with the type of fruit. Rupasinghe et al. (2006) recorded 86 to 413 mg gallic acid per 100 g in plum. Whereas Nisar et al. (2015) recorded 2.63 to 9.93 mg gallic acid per 100 g total phenolics, while in the present study total phenolic contents in plum were recorded as 3.34 mg gallic acid per 100 g. The difference in total phenols might be due to difference in extraction methods, environmental factors, and genotypes.

CONCLUSION

It can be concluded from this study that these indigenous fruit species are popular in local communities and are mostly consumed in areas where they are produced. Very little fruits are being sent to the main urban markets of this region or Pakistan. Therefore, in this regard a comprehensive research studies are required to supply disease free planting material, to give a detailed plan for managing trees and fruits, to provide indices for maturity, to develop an optimum system for handling, processing, and packaging of these fruits after harvest. Thus, a complete value chain approach is needed to rectify these issues and to provide a long-term solution for these species, so that all the stakeholders involved in this whole chain are benefitted either through addressing the issue of malnutrition or by earning some good living.

Author contribution statement

Mehdi Maqbool: Conceptualized idea, conducted this research work, collected data and data analysis. Noosheen Zahid: Conceptualized idea and designed this research work and collected data. Syed Zulfiqar Ali Shah: Assisted in methodology, validation, and data collection. Abdul Hamid: Assisted in methodology, validation, editing and reviewing.

Acknowledgements

Authors are highly thankful to the local farmers for providing information and fruit samples free of cost to conduct this study.

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