Wheat is a staple cereal crop that is grown in different climates, although most suitably in the temperate regions with moderate rainfall in the globe and is commonly planted as an annual crop. It is one of the pillars of the food security in the world since it contributes about 20 per cent of the total amount of dietary energy and protein to the global population (Shewry and Hey, 2015). It is of vital significance in the Agricultural Economy of India and ranked 2^nd in the world in the production of wheat after China (Shukla et al., 2024). It is a highly nutritious food that has carbohydrates, protein and other helpful components (vitamins and minerals) (Khalid et al., 2023; Garg et al., 2021). The use of chemical fertilizers to increase crop production has never been higher than it has been today as the global population keeps increasing the demand of food. The extensive and unreasonable use of synthetic fertilizers, however, has caused extensive destruction of the environment, such as acidic soil, groundwater and a decrease in the diversity of microorganisms in the soil (Savci, 2012).
       
The current study that indicates the use of the waste product of the fruit peels, which indicated a possibility of coming up with natural fertilizers. The processing industries produce large amounts of biodegradable waste especially the peels which are usually dumped in landfills thus adding to the greenhouse gases. The peels of Pomegranate (Punica granatum) and Orange (Citrus sinensis) are of specific interest because of the high nutritional content. The levels of bioactive compounds like polyphenols and essential minerals (K, Ca, Mg) are high in pomegranate peels, whereas Vitamin C (ascorbic acid), soluble sugars and essential oils are high in orange peels and can be used as natural growth biostimulants (Somdutt et al., 2021 and Pathak et al., 2017). Studies have revealed that organic amendments obtained by using fruit wastes have the potential to enhance soil structure and bioavailability of micronutrients including Zinc (Zn) and Magnesium (Mg) after a process known as chelation (Zema et al., 2018). Although the individual action of different organic manures is well-reported, the interaction of pomegranate powder and orange powder on the morpho-biochemical characteristics of wheat is not fully researched. Plant height and days to 50 per cent flowering are morphological parameters that play an important role in determining plant vigor, whereas biochemical attributes like protein and micronutrient content are important parameters that control the nutritional quality of the final grains yield (Sattar et al., 2021 and Jamal et al., 2019).This research was directed to test the possibility of using pomegranate and orange peel powder as natural fertilizers in growing wheat. The main goal was to examine their effects on morphological growth (height, flowering and yield), biochemical parameters, that is, the enrichment of protein, Zinc, Magnesium and Vitamin C. This study would fill the gap in the understanding of waste management and crop physiology in order to present a long-term framework of bio-organic residues application in improving wheat production.

Experimental design
 
The field experiment was done in completely randomized design (CRD) in four replications during Rabi season 2023 on 5^th November 2023. The study has been prepared using five treatments conducted independently using a managed pot culture system at a private residential site in Panipat, Haryana, India (29.3885° N latitude and 76.9587° E longitude) and using sandy loam soil of the farming land. The biochemical analysis of the samples was done in the biochemistry lab, ITM University, Gwalior, Madhya Pradesh, India. The five treatments are as follows:
Treatment 1: Soil per-se.
Treatment 2: Soil + NPK fertilizer. 
Treatment 3: Soil+ Orange peel powder.
Treatment 4: Soil+ Pomegranate peel powder.
Treatment 5: Soil +Oranges peel powder +pomegranate peel powder.
 
Materials
 
Processed fruit peels (Citrus sinensis and Punica granatum) as in powder form, soil from farming land, pots for sowing and wheat grains for sowing has been purchased from local market of Panipat.
 
Preparation of fruit peel powder
 
Procedure
 
Fruit peels were collected in a single batch from local fruit juice vendors of Panipat. Thereafter, the fruit peels were cleaned thoroughly to remove foreign materials with the tap water and shade dried at room temperature of 30°C for 4-5 weeks. After drying, peels were separately ground into 100 mesh fine particles by use of laboratory blender at 3000 rpm and passed through 2 mm sieve then stored in sterile polythene bags for further experimental work (Fig 1) (Halpatro et al., 2019).


       
Every pot was prepared using 5 kilo gram of soil and 100 g of fruit peel powder were applied as per the treatments. After preparation, seeds were sown in each treatment and all the agronomic practices were followed to raise the crop. The pots were always kept under natural environment conditions and all the traits were recorded by using destructive sampling method.

Estimation of biochemical parameters
 
The protein content in the grains was estimated by Lowry method (Lowry et al., 1951). Determination of mineral content (Zinc, Iron and Magnesium) in seed sample was done using Atomic Absorption Spectroscopy (AAS) by standard method (AOAC International, 2019). Whereas, the analysis of Vitamin C was done by Redox titration of ascorbic acid, as a reducing agent, ascorbic acid reacts with the dye, causing a color change that signifies the end point (Vogel et al., 2000).
       
Data were analyzed using Analysis of Variance (ANOVA) and significant differences were identified. Correlation for morphological and biochemical parameters were done using Pearson correlation matrix (Gomez and Gomez, 1984).

Morphological performance
 
The analysis of variance found significant difference (P<0.01 and P<0.05) in the growth performance of the different treatments. The mean performance of morphological parameters in wheat was presented in Table 1.  The emergence time among all the treatments was varied from 3 days to 5.33 days with a grand mean of 4.20±0.17. The minimum days taken by the seed to germinate was 3±0.00 days in T1 followed by T3 (4.00±0.00), T2 (4.33±0.29) and T4 (4.33±0.29). Whereas, the maximum days was taken by T5 (5.33±0.29).The 50% flowering was observed between 74.00 to 76.00 days with an overall mean of 74.93±0.12. Early days to 50% flowering was calculated in T1 (74.00±0.00) followed by T2 (74.33±0.29) and T4 (75.00±0.00) while the late days to 50% flowering was noticed in T5 (76.00±0.00).   

 
       
The mean value for no. of tillers in all the treatments was observed 8.46±1.13. The highest value was recorded for T5 (9.67±0.58) followed by T1 (9.00±1.00) and T2, T4 (8.00±1.53) whereas, the lowest value was recorded for T3 (7.67±0.58).No. of spikes per plant was ranged from 24.33 to 29.00 with an overall mean of 27.13±0.72. The maximum spikes were observed in T5 (29.00±0.50) followed by T3 (28.67±0.58) and T4 (27.00±0.50) while, the minimum value was observed in T1 (24.33±1.26).Similarly, the mean value for spike length was ranged from 10.67 cm to 12.67 cm with a grand mean of 11.53±0.72 cm. The maximum length was measured in T3 (12.67±0.76 cm) followed by T4 (12.33±0.76 cm) while the minimum was measured in T1 (10.67±0.58 cm). The increase in spike length may be attributed to the continuous release of nutrients, particularly potassium and calcium, from fruit peel powders, which play a role in cell elongation and spike development. Plant Height was ranged from 54.00 cm-63.33 cm with an overall mean of 59.93±1.44 cm. Both tall and short plant heights have their own significance in crop performance. The maximum height was measured in T4 (63.33±1.26 cm) followed by T3 (63.00±2.65 cm) and T5 (62.33±1.00 cm). The minimum was measured in T1 (54.00±1.80 cm) followed by T2 (57.00±0.50). Earliness is considered as a desirable parameter for any treatment, as it enables the crop to escape terminal stresses and ensures timely harvesting. The mean value ranged from 113.00-114.33 with a grand mean of 113.79±0.46 days. The earliness in the treatment was calculated in T4 (113.00±0.50) followed by T2 (113.33±0.76) and T3 (114.00±0.50). The variation in maturity time under different treatments suggests that nutrient composition and release patterns influence crop duration.
       
Per plant yield was ranged from 4.70-9.40 g with an overall mean of 6.92±0.20 g. The maximum yield was measured in T5 (9.40±0.05 g) followed by T4 (8.60±0.28 g) whereas, the minimum was measured in T1 (4.70±0.26 g) followed by T2 (5.70±0.25 g) and the mean value for thousand seed weight was ranged from 25.10-30.50 g with an overall mean of 28.12±0.73 g. The maximum weight of thousand seeds was recorded in T5 (30.50±0.55 g) followed by T4 (29.40±0.46 g). While, the minimum was recorded in T1 (25.10±0.79 g) followed by T3 (27.50±1.00 g).
 
Nutritional parameters
 
The mean performance for qualitative traits was presented in Table 2. The mean value for protein was ranged from 0.17-0.24 with an overall mean of 0.24±0.00. The maximum estimated value for protein was found in T5 (0.24±0.00) followed by T4 and T2 (0.23±0.00) while, the minimum value was found in T3 (0.17±0.00).The range for iron is observed in between 30.37-32.84 with a grand mean of 31.25±0.08. The maximum value of iron was recorded in T4 (32.84±0.04) followed by T5 (31.55±0.03) and T3 (31.12±0.08) whereas, the minimum value was recorded T2 (30.37±0.13). The increase in iron availability can be linked to organic acids released during the decomposition of peel powders, which enhance Fe solubility and uptake by plants. The overall mean for zinc was recorded 22.49±0.15 with a range from 20.25-26.12. The maximum value was calculated in T5 (26.12±0.08) followed by T4 (23.45±0.03) and T3 (22.37±0.15). The minimum value was calculated in T1 and T2 (20.25±0.25). Zinc is a vital micronutrient for enzymatic activity and grain nutritional quality. The mean value for magnesium was ranged from 2.82-5.86 with an overall mean of 3.91±0.13. The maximum magnesium content was recorded in T5 (5.86±0.04) followed by T4 (4.22±0.09) and T3 (3.75±0.49) whereas, the minimum was recorded in T2 and T1 (2.92±0.03; 2.82±0.03).


 
Vitamin C
 
No vitamin C was detected across treatments, which is expected since wheat grains naturally contain very low to negligible levels of vitamin C compared to fruits and vegetables.
 
Correlation matrix of various wheat parameters
 
The heatmap visualization of wheat parameters are given in Fig 2. Among all the parameters, a strong positive correlation was observed between grain yield per plant (GYPP) and thousand seed weight (TSW) (r = 0.93), days to emergence (DTE) (r = 0.85) and days to 50% flowering (DFF) (r = 0.83). This suggests that treatments leading to higher seed weight and longer vegetative phases generally resulted in higher yields in this dataset. Plant height is strongly correlated with Spike Length (SL) (r = 0.77) and number of spikes per plant (NSPS) (r = 0.85). Days to emergence (DTE) is almost perfectly correlated with thousand seed weight (TSW) (r = 0.96). Whereas, number of seeds per spike (NSPP) shows a moderate negative correlation with GYPP (r = -0.58) and PH (r = -0.60), which might indicate a trade-off between seed number and seed weight/size under these specific treatment conditions.


 
Correlation matrix for various nutritional parameters
 
The correlation among nutritional parameters was depicted in Fig 3. Where, it is observed that there is a perfect positive correlation between zinc and magnesium levels (r = 0.99). This indicates that as zinc content increases across treatments, Magnesium content increases almost identically. Iron shows a positive correlation with Zinc (r = 0.65) and Magnesium (r = 0.58), suggesting the enrichment of the minerals. There is a positive but weak correlations observed with the minerals which is ranged from 0.17 to 0.29. However, the protein content of T3 (0.17 mg/dl) has no negative effect on mineral content and T3 observed increasing mineral content as compared to T1 and T2.


 
Identification of best treatment based on morphological and nutritional parameters
 
The identification of the most effective treatment was based on the comparative performance of morphological and qualitative traits across all five treatments. The results revealed that the application of orange peel powder and pomegranate peel powder as natural fertilizers exhibited superior performance over T1 (Soil only) and T2 (Soil + NPK). Treatments T3, T4 and T5 significantly enhanced the growth and yield attributes of wheat, along with improving the nutritional composition of the harvested grains. Among these, T5 (Soil + Orange peel powder + Pomegranate peel powder) was the most effective. The interaction between the two peel powders gave a synergistic effect which resulted in significant changes in most parameters to enhance yield including the number of tillers per plant, number of spikes per plant, number of seeds per spike, grain yield per plant and thousand-seed weight. Moreover, T5 had significant improvement in qualities such as increase in protein and iron levels and maximum zinc and magnesium levels in the grains. These results indicate that incorporation of orange and pomegranate peel powder in the soil can be of great significance in enhancing the yield performance as well as grain quality of wheat. In Table 3, the separate comparative analysis of the treatments T3, T4 and T5 is given.


       
The results of the present investigation indicate the high bio-fertilizing capacity of peel-based organic amendments obtained in the fruits and their application in the betterment of the agronomic and nutritional composition of wheat (Triticum aestivum L.). The results of the growth performance, yield and nutrient accumulation observed among treatment groups indicate that organic residues such as pomegranate peel and orange peel are powerful biostimulants (Charanjeet and Gayatri, 2016).
 
Morphological, yield and nutritional dynamics
 
The study revealed that integrated treatment T5 (Orange + Pomegranate peel) significantly enhanced yield attributes, including a maximum grain yield per plant (GYPP) of 9.40 g and thousand seed weight (TSW) of 30.50 g. The strong positive correlation between GYPP and TSW (r = 0.93) indicates that yield enhancement was primarily driven by increased grain density and size. The TSW showed a statistically significant increase, indicating better grain filling. This is consistent with research suggesting that organic amendments provide a sustained release of macro and micronutrients, specifically potassium (K) and calcium (Ca), which are vital for cell elongation and reproductive development in cereals (Sarker et al., 2022 and Yimer, 2021). While T5 showed a slight delay in 50% flowering (76 days), this longer vegetative phase was positively correlated with yield (r = 0.83), allowing for greater photosynthate accumulation. Interestingly, the application of organic fertilizers tended to prolong the vegetative growth period. Plants treated with organic amendments took longer to reach heading and physiological maturity compared to those in nutrient-deficient soils, allowing for more accumulation of dry matter (Haile et al., 2020). In contrast, the moderate negative correlation between Number of Seeds per Spike (NSPP) and GYPP (r = -0.58) suggests a physiological trade-off where the plant prioritizes seed weight (quality) over seed quantity under these organic treatments. The primary objective of this study was to address “hidden hunger” through mineral enrichment. Treatment T5 maximized the accumulation of Zinc (26.12 mg/kg) and Magnesium (5.86 mg/kg). The fact that Zinc and Magnesium have an almost perfect correlation (r =0.99) indicates that the uptake pathway or bioavailability might be related through the organic structure of the fruit peels. It was discovered that organic amendments had a strong effect of raising the level of zinc (Zn), iron (Fe), Manganese (Mn) and Copper (Cu) in grain samples. This is credited to the release of natural chelating agents in the process of decomposition of organic matter (Dwivedi et al., 2020). The rise in Iron concentration, especially T4 and T5, can be explained by the liberation of organic acids in peel powders decomposition. These acids are natural chelators and increased the solubility as well as uptake of the metallic ions by the plants (Shukla et al., 2024). Interestingly, T5 had the highest level of protein content, but weakly correlated with the mineral content. It means that mineral bio-fortification of wheat grains through fruit peel amendments can be done regardless of the protein synthesis, which is a flexible avenue to enhance the quality of grains without necessarily affecting the protein/starch ratio (Mahajan et al., 2024). The superior performance of T5 over the chemical check (T2/NPK) highlights the “synergistic effect” of combining different organic residues. Orange peels contain high levels of Vitamin C and citric acid (that facilitates the solubility of the mineral), whereas pomegranate peels contain polyphenols and potassium in large amounts. It is probable that the combination of such materials enhanced the optimal state of the soil microbiome and nutrient availability more so than synthetic NPK. It helps make the shift towards the model of the circular economy of agriculture, as the upcycling of organic waste instead of using a substance that negatively impacts nature will be used (Bahaudin et al., 2022).

The experiment has shown that organic peel amendments of fruits, particularly the joint use of orange and pomegranate peel powders have remarkable effects on the enhancement of both morphological and nutritional qualities of wheat. The synergies of these natural fertilizers boosted the production of tillers, growth of spikes, grain productivity and the seed weight as well as the protein, iron, zinc and magnesium levels in the grains. Moreover, the treatment was better when it comes to mineral bio-fortification, as it gave the highest levels of zinc, iron and magnesium and a very high correlation was found between the accumulation of Zinc and Magnesium. The integrated treatment (T5) was the most effective as compared to the sole application of either peel powder or conventional NPK fertilizer. These findings indicate that fruit peel powders do not only contain necessary macro and micronutrients but they also enhance the health of the soil and the production of crops in a sustainable manner. Hence, fruit peel-derived fertilizers shall hold strong potential as an eco-friendly, cost-effective strategy to boost wheat productivity and nutritional value, while addressing issues of organic waste utilization and environmental sustainability. Therefore, the fruit peel-based fertilizer products will have a high potential of being an environmentally friendly, low cost, strategy in enhancing the productivity and nutritional content of wheat as well as solving the problems of using organic waste and environmental sustainability.

The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.