One of the biggest challenges facing modern agriculture is producing enough food to feed the world’s population of 8 billion without depleting natural resources (Becagli et al., 2022). Crop productivity has relied on the use of fertilizers to keep pace with population expansion, but due to their intensive use, natural resources are rapidly degrading and soil and water are being used in unsustainable ways. Alternative approaches are needed to increase crop productivity without endangering the environment, farm animals, or human health in light of these pressing environmental concerns (Zhu et al., 2021).
       
Mung bean (Vigna radiata L.) is one of the solutions to this problem, as it is a legume crop and is characterized by a short growing season (90-120 days) and its tolerance to drought conditions in all stages of its growth except the flowering stage. Its seeds are used in human and animal nutrition because of their protein and carbohydrate content, in addition to its use as green fodder for animals, as well as its use as green fertilizer to improve soil properties, especially because it contains iron, calcium, potassium, magnesium and zinc. All of this qualifies it to be part of sustainable development (Smiglak-krajewska et al., 2021). It is widely cultivated in the central and southern governorates of Iraq, while its cultivation is still limited in northern Iraq due to many reasons, including the lack of modern research in these areas, especially regarding the planting date. This is more necessary when climate change occurs, as we are experiencing now (Ali et al., 2025).
       
The planting date is of great importance in crop cultivation, as it varies according to the locations where the crop is grown (Van Loon et al., 2018). In general, planting dates are a complex issue in legume crops due to the fact that varieties belong to multiple maturity groups and are greatly affected by the environment. It is necessary to determine the appropriate date for planting varieties with environmental adaptation. The reason for choosing these dates to plant this crop is after the harvest of wheat and barley (Ali et al., 2021). Ali et al., (2024) showed that when planting mung beans at different dates, a significant superiority of some dates was observed at the expense of others in most traits. Research by (Ali et al., 2024b) showed that late maturing genotypes produce tall plants with many branches, while early maturing genotypes produce few branches. It was also found that plant height decreases with delayed planting date. Khatik et al., (2022); Eshanee et al., (2023); Arya et al., (2024); Rai et al., (2024) found that when planting mung beans at three dates (25/4, 5/5, 15/5) in Pakistan, planting date 25/4 caused a significant increase in plant height, pod length, number of pods per plant, seed yield per unit area and biological yield compared to other dates. Despite the importance of this crop, its productivity rate is still low compared to global production due to the lack of interest of specialists in variety development programs and the reliance of Iraqi farmers on growing the only variety (green) that is locally traded and suitable for the conditions of the region. Ali (2021) indicated in his study in which he used many varieties that there were significant differences between the traits and for three periods of growth (Ali et al., 2024c) also agreed with him through their study (Ali et al., 2023b) noted in his experiment that included two varieties, where he recorded significant differences between the varieties in most of the studied traits.
       
The excessive use of chemical fertilizers in agricultural production has led to an increased need for new products that improve the quantity and quality of legume crops in a more sustainable manner. One such approach is the use of alternatives to or reduction of chemical fertilizers. Wood vinegar (pyrogensic acid), balanced nano-complex fertilizer and amino acids have emerged and have been successfully applied in agricultural production due to their ability to improve the growth and productivity of legume crops. In addition to neglecting the foliar nutrition factor and not differentiating between its modern products, especially with the presence of materials that have proven their efficiency in a distinguished manner, such as wood vinegar, nano fertilizers and amino acids, which are among the important materials in improving the performance of varieties, increasing their productivity and improving their quality, especially the above materials, as they play a role in building hormones and plant protein, an important role in the process of photosynthesis, chelating nutrients and regulating the acidity of the cell. Recently, wood vinegar (pyroligneus acid) has been used as an organic agricultural product in Italy (Italian Ministerial Decree 6793, 2018). It is a by-product obtained from the condensation of gases produced during the pyrolysis of woody biomass and consists of 200 or more water-soluble compounds, including phenols, tannins, esters and acetic acids (Mathew et al., 2015). Get in touch (Ali et al., 2021) concluded that the use of some materials led to an improvement in most of the studied crop traits. Abdulqader et al. (2021) showed that plant yields differed significantly due to the addition of some stimulating substances compared to the control treatment, achieving an increase of 27.13%. Ali et al. (2023a) conducted a study on the effect of some germination and growth stimulants and found a significant effect on crop traits when adding stimulants compared to the control treatment. Mota et al., (2021); Ali et al., (2025) concluded that spraying nano-fertilizer at a concentration of (45 mg L^-1) on mung bean plants caused a significant increase in the number of plant branches, biological yield and harvest index. This study aims to determine the best date for planting mung beans without affecting the cultivation of strategic crops (wheat and barley), to identify the best local varieties that have not been thoroughly tested and to test some modern natural materials to complement chemical fertilization to produce a crop with natural advantages and to create a distinct quantitative and qualitative balance to gradually move towards sustainable agriculture.

The field experiment was conducted in the fields of the College of Agriculture and Forestry at the University of Mosul in 2024. The soil specifications are shown in Table 1. It included three factors: Two varieties of local green (V1) and black (V2) mung bean crops; three planting dates (June 1, June 15 and June 30); and the third factor: spraying with three types of foliar fertilizers: wood vinegar, balanced nano-NPK fertilizer and amino acid fertilizer. All materials were sprayed at a concentration of 2 ppm, in addition to water spraying (control treatment). The spraying was applied to the plants at three stages (at branching, at the beginning of flowering and at the time of pods formation).


       
According to the experimental factors, a randomized complete block design was used as a factorial experiment with a split-plot system, where the varieties were placed in the main plots, the planting dates were placed in split-plots once and the fertilization treatments were placed in split-plots twice. 24 experimental units were available for each replicate, with dimensions of 2*2 m and an area of  4 m², where 10 plants were planted in each row with a distance of 20 cm between holes and 40 cm between lines, so there will be 5 rows. 0.5 m was left between experimental units and 1 m between replicates.
       
The following traits were studied: Plant height (cm), number of branches per plant, leaf area per plant (cm² per plant), pod length (cm), number of pods per plant, number of seeds per pod, Weight of 1000 seeds (g), seed yield (g plant^-1), biological yield (g plant^-1) and harvest index (%). After recording the data, they were statistically analyzed according to the design used and Duncan’s multiple range test was used to compare the means.

The results in (Table 2) show significant differences between the varieties, as the green variety was significantly superior to the black variety in the averages of most of the studied traits. The results were as follows: plant height (84.148 and 83.298 cm), number of branches (4.625 and 4.511 branches.plant^-1), leaf area (259.522 and 250.697 cm²/plant^-1), pod length (7.211 and 6.908 cm), number of pods (108.300 and 99.825 pod/plant^-1), number of seeds (11.783 and 11.308 seeds.pod^-1), biological yield (116.858 and 107.014 g.plant^-1), seed yield (42.069 and 37.239 g.plant^-1) and harvest index. (36.132 and 34.846%) for the green and black varieties, respectively. This was similar to what was obtained by Ali et al., (2021); Ali et al., (2024c); Ali et al., (2024b): Ali et al., (2023b). This is due to the Iraqi farmer’s reliance on cultivating the locally traded green variety, which is suitable for Iraqi conditions and has better specifications than the black variety. This is due to the difference in the genetic makeup of the two varieties and thus their variation in response to prevailing environmental conditions, especially when significant climatic and environmental changes occur. This is due to the varieties belonging to multiple maturity groups and being greatly affected by the environment. This necessitates determining the appropriate date for planting varieties with different environmental adaptations (Ali et al., 2024a., Ali et al., 2025).


       
The results of (Table 2) indicate that planting dates had a significant effect on most of the studied traits. The first date achieved a significant superiority over the other dates, recording an average of 84.587 cm for the trait of plant height, 265.588 cm² for the trait of leaf area and 7.212 cm for pod length, compared to the second date, which recorded a significant superiority rate of 36.632% for the harvest index, while the third date was significantly superior in the traits of the number of branches (4.670 branches. plant^-1), the number of pods (107.750 pod.plant^-1), the biological yield (118.720 g.plant^-1) and the seed yield (41.609 g.plant^-1). The superiority of early planting dates over late planting dates in vegetative growth characteristics may be attributed to the longer vegetative growth period of the crop, which allows plants to utilize more light, thus increasing the efficiency of photosynthesis. This is positively reflected in the growth and development of plants, including encouraging the growth of green parts and increasing plant height, leaf area and pod length. The superiority of late planting dates in crop characteristics and components may be due to the availability of suitable environmental conditions such as appropriate temperature and lighting, which help the plant form a reproductive group that matches the requirements of seed production. Consequently, the carbohydrates stored in the meristematic parts will be transferred to the economic part once it is formed. These results are consistent with the findings of (Van Loon et al., 2018; Ali et al., 2021; Ali et al., 2024a).
       
From the results of the nutritional materials added to the mung bean plants, it is noted that the addition of these materials led to an improvement in most of the studied characteristics compared to the control treatment, especially when adding wood vinegar, as we notice a significant superiority when adding this material with all the studied characteristics, followed by amino acids and balanced nano-complex fertilizer. Water spraying had the lowest values recorded in the treatment. This may be attributed to the role of these materials in increasing the transfer of carbohydrates to the active areas during the reproductive stage, which affected reducing competition for the products of metabolism, positively affecting most of the characteristics, as these materials contribute to increasing the photosynthesis process and thus preparing new growth sites with growth requirements, reducing their abortion. Materials that have proven their efficiency in a distinctive way, such as wood vinegar, nano-fertilizers and amino acids, are among the important materials in improving the performance of varieties, increasing their productivity and improving their quality, especially the above materials, as they play a role in building hormones and plant protein, an important role in the process of photosynthesis, chelating nutrients and controlling the acidity of the cell. Recently, wood vinegar (pyroligneus acid) has been used as an organic agricultural product in Italy (Italian Ministerial Decree 6793, 2018). It is a by-product obtained from the condensation of gases produced during the pyrolysis of woody biomass. It consists of 200 or more water-soluble compounds, including phenols, tannins, esters and acetic acids. This has been confirmed by studies by Mathew et al., (2015); Abdulqader et al., (2021); Ali et al., (2025). All interactions behaved as single agents in terms of superiority and distinction, whether for binary or triple interactions.

The local green variety was superior in all studied traits. The 1/6 planting date was significantly superior in plant height, leaf area and pod length, while the 15/6 planting date was significantly superior in harvest index only, while the 30/6 planting date was significantly superior in the number of branches per plant, number of pods, biological yield and seed yield. Foliar fertilizer spray treatments recorded a significant superiority compared to water spraying, especially when spraying with wood vinegar and some traits were significantly affected by the use of balanced nano-compound and amino acids, especially seed yield.

The authors are very grateful to the University of Mosul/College of Agriculture and Forestry for its facilities, which improved the quality of this article.

The authors have no conflict of interest to declare.