Sustainable Soil Management and Climate Adaptation through Pulses Cultivation: A Comprehensive Review

Pulse is originated from Latin word “Puls,” which means pottage or cooked seeds often used to produce thick soup or porridge (Singh et al., 2017). The word “legume,” means “to gather,” is derived from a Latin word “legere,” which refers to traditional practices of collecting seeds by hand rather than having them threshed from plants like cereals (Benouis, 2017). Pulse crops are actually dry seeds of leguminous plants containing low fat content hence, distinguishable from leguminous oil seeds. The most well-known and frequently used types of pulses are dried beans, lentils, chickpeas, and peas (Joshi et al., 2020). In terms of food and vegetable protein sources, as well as fodder, it is second largest family after Poaceae (formerly Gramineae). Their flowering is often photoperiodic, and productivity is determined by an annual fruiting cycle, whose duration is controlled by the day length response (Hutchinson, 1970). Beans (Phaseolus vulgaris), lentil (Lens culinaris; approximately 9000 years (Fratini et al., 2014), and soybean (Glycine max; approximately 3000 years (Singh et al., 1987) are some of the earliest domesticated legumes. One of the seven Prehistoric crops of Near East is chickpea (Cicer arietinum). Groundnut (peanut) and soyabean are grain legumes, but they are not considered pulses because they are primarily used for oil extraction (Getachew, 2019). Pulses contribute 30% of the total amount of protein and nitrogen needed by humans in the diet, and they are produced on about 12–15% arable (cultivated) land of the world (Graham and Vance, 2003). Pulses are high in protein and are often referred to as “poor man’s meat” (Kushwaha and Kumar, 2013). Pulses contain same number of calories but twice the protein content as compared to cereals (20-25%) and are almost as high as meat and chicken. However, protein content is of lower quality than animal protein, which are a staple diet all around the world.100g of dry pulses contains around 350 Kcal of energy (Marinangeli et al., 2017). Pulses are a major source of dietary fiber, have little to no fat and have no cholesterol (Table 1). Additionally, they don’t contain gluten and are loaded with vitamins and minerals that are essential for a healthy life (Getachew, 2019).

About 89 percent of people in India consume pulses at least once a week, compared to only 35.4% who consume fish, poultry, or beef at least once a week. This makes pulses the most common protein source consumed in India (Kumar, 2024). Pulses can be cultivated in low fertilize soils and require less time and moisture to grow and harvest than that of cereals. Due to early harvest “Haricot” beans are referred as “First Aid Crops” by farmers (Getachew, 2019). Pulses are a significant food path in the world. They contribute significantly to food production system by enriching soil health through biological N-fixation (Singh et al, 2017) and reduce need of synthetic nitrogen fertilizer. It also mobilize essential micro- and macro-nutrients (Nath Bhowmik and Das, 2018). The deep root system and organic matter of pulses also increase diversity of micro flora hence adding to soil physical properties by increasing porosity, cohesion and water holding capacity (Meena et al., 2018). Benefits of pulses as showed in Figure 1.

Table 1: Types of Pulses and their nutritional values

Drought is a major issue worldwide, however some pulses like chickpea, lentils and Mung-bean complete their lifecycle in a short duration and avoid stress and maintain water supply by access to deeper soil moisture. It also increase xylem vessel diameter to improve hydraulic conductivity (Elhaissoufi et al, 2022). Pulses can survive under drought condition by maintaining cell wall elasticity and preventing cell membrane leakage, scavenging reactive oxygen species (ROS) by enhanced antioxidant systems (Seleiman et al., 2021). Pulses also have ability to fix N under drought stress by selecting drought-tolerant rhizobium from inoculation and accumulating N reserves in stem, adjusting root-shoot ratio for remobilization during grain filling stages (Del-Canto et al., 2023).

This review is aimed to synthesize current knowledge on pulses, including their nutritional value, role in soil enrichment through biological N-fixation and organic matter dynamics, drought tolerance mechanisms, benefits in intercropping and crop rotation systems for sustainable agriculture, and effectiveness as cover crops in soils to control erosion.

Legumes as soil benefits

Legumes have long been recognized and valued as “soil building” crops. Growing legumes have improved soil quality through their beneficial effects on soil biological, chemical and physical conditions by enhancing soil fertility through biological nitrogen fixation, organic residue inputs, and stimulation of soil microbial processes that regulates nutrient cycling(Jha et al, 2021). When properly managed, legumes can enhance the following soil properties.

Legumes have the ability to fix atmospheric N through a symbiotic relationship with rhizobia, a kind of bacteria, available in soil. A hallmark trait of legumes is their ability to develop root nodules and to fix N2 in symbiosis with compatible rhizobia (Graham and Vance, 2003). Formation of symbiotically effective root nodules involves signaling between host-plants and microsymbiont. Flavonoids and/or is flavonoids released from roots of legumes hosts induce transcription of nodulation genes in compatible rhizobia, leading to the formation of lipo-Chito oligosaccharide molecules that, in turn, signal the host plant to begin nodule formation (Vance, 1991). This process adds in a significant amount of N to the soil, reducing needs for synthetic nitrogen fertilizer. Through symbiosis with Rhizobium spp., legumes convert atmospheric N2 into plant available ammonia via the nitrogenase enzyme complex, contributing approximately 50-300 kg N ha-1 year-1 depending on species and environmental conditions (Peoples et al., 1995). Some 40 to 60 million metric tons (Mt) of N2 are annually fixed by important legumes, with another 3-5 million Mt fixed by legumes in natural ecosystems (Montagnini and Ashton, 1999). In comparison with artificially produced nitrogen fertilizer, which consume huge amount of fossil fuels and significantly contributes to GHS (Erisman et al., 2008) nitrogen fixation biologically by legume crops offers a low emission renewable pathway to enhance nitrogen pool of the soil. While diazotrophs like cyanobacteria and Azotobacter also contribute to fix nitrogen and improve the productivity depending on the soil organic matter (Cleveland et al., 1999). In contrast, symbiosis between legumes and rhizobia provides a reliable and effective source of nitrogen, capable of supplying 100-300 Kg N ha-1 Year-1 (Peoples et al., 1995), significantly reducing the dependence on artificial inputs.

Incorporating legume green manures increase organic matter content of the soil. Incorporation of legume biomass increases soil organic carbon pools because it contains relatively low C:N ratis, which promotes rapid microbial decomposition and efficient nutrient mineralization (Rodríguez et al, 2022). During decomposition, legume residues release labile carbon substrates that stimulate microbial growth and enzymatic activity, leading to the formation of stable soil aggregates and improved water retention capacity (Thorup-Kristensen et al., 2012). Enhanced organic matter also leads to better nutrient cycling, which is critical for maintaining soil fertility. The advantages of green manures are diverse and can contribute to sustainability of agro- ecosystems through different ways (Yao et al., 2019). Detailed illustration is presented in (Figure 2). Green manuring is an agricultural practice that involves growing specifics crops especially pulses and then incorporating them into the soil before seeds development, these crops are not harvested for food or fodder but are turned under while still to green decomposes and enrich the soil. Pulses like green gram (Vigna radiata), cowpea (Vigna unguiculata), lentil (Lens culinaris), and chickpea (Cicer arietinum) are excellent options for green manuring due to their high biomass, nitrogen fixation ability and drought resilient (Meena et al., 2018). Green

manuring consists of two types, in-situ green manuring in which pulses are grown in a same field where the following crop are cultivated, after reaching the flowering the green biomass is incorporating directly into the soil. The other one is ex-situ green manuring in which pulses are grown in separated field then harvest and green biomass is transport and apply as a mulch or incorporating into others field for soil enrichments (Tanveer et al., 2019). Legumes have the ability to form a symbiotic relationship with Rhizobium bacteria in their root’s nodules. These bacteria can fix atmospheric N2 into usable forms by crops, when biomass of legumes return to the soil increases the availability of N and reduces the need of synthetic fertilizers, and allows to improve N-uptake effectiveness and decrease N leaching losses (Fowler et al., 2004). It also enhances soil organic matter (SOM), through the direct additions of biomass, when pulses are incorporated into soil their materials like shoot and roots becomes and source of organic input, and this biomass contains a mix readily degradable compounds like (sugars and amino acids), and structural carbohydrates (Cellulose and hemicellulose), which decomposes, soil microorganisms begin breaking down these materials using the simpler compounds for rapid energy and slowly the processing the more resistance ones (Kumar et al., 2020b). This microbial activity transforms the biomass into various organic forms, including microbial biomass, organic acid and humic substances. Some of these products becomes stabilize in the soil through interaction with minerals or incorporation into soil aggregates, contributing to the long term buildup of stable SOM (Thorup-Kristensen et al., 2012). As a result, it enhances the soil fertility by improving its ability to retain and cycle nutrients. When pulses like green gram, cowpea, and sun hemp are grown and incorporated into soil, they decompose the gradually and release key nutrients particularly nitrogen into the soil profile. Unlike synthetic fertilizers that releases nutrients rapidly and are prone to leaching, despite this green manuring provides a slowly, and steady release of nutrients which reduces the losses of N (Mat Hassan et al., 2012). As research reported that green gram as green manures added N 30 kg ha-1, which becomes available to subsequent crop in wheat (Sangakkara et al., 2002). As other research reported that green manuring accumulated N 53-76 kg ha-1 under soybean-wheat, fallow-wheat, huai bean-wheat, and green gram-wheat cropping system and amount of N utilized by wheat was 7-27 kg ha-1 (Dabin et al., 2016). Under rice-wheat cropping system green manuring of Sesbania and mungbean resulted in recycling of N 77-113 kg ha-1 and increased the productivity of rice-wheat cropping system by 0.5-1.3 t-1 ha y-1 (Sharma and Prasad, 1999).

Legume plants support a diverse microbial community by releasing root exudates e.g., amino acids, sugars, and organic acids that serve as substrate for soil microorganisms, lending a greater stability into the total soil life (Yuvaraj et al, 2020). Legumes also foster production of a greater total biomass in the soil by providing additional N (Virk et al., 2021). As research showed that SOM increased by 0.1-0.3% per year, and addition of dry biomass before wheat sowing into soil was 3.5 t ha-1 (Mahey et al., 2024).

Soil microbial diversity plays a fundamental role in sustaining soil health and ecosystem functionally. It encompasses a wide range of microorganism, including bacteria, fungi, actinomycetes, protozoans, and archaea each performing distinct but interconnected with ecological functions (Hakim et al, 2021). This diversity underpins key soil processes such as nutrient cycling, organic matter decomposition, soil structure formation, pathogen suppression, and plant growth promotion making it cornerstones of productive and sustainable agroecosystem (Van Der Heijden et al., 2008). Microorganisms regulate the mineralization and immobilization of nutrients like nitrogen (N), phosphorous (P), and sulfur (S), nitrogen fixing bacteria e.g Rhizobium Azotobacter convert atmospheric N2 into plant available form, while phosphate- solubilizing microbes enhances the bioavailability of phosphorus bound in soil minerals (Fierer, 2017) (Figure 2).

Legumes, through their root exudates and symbiotic relationships with nitrogen-fixing bacteria (Rhizobium spp.) and arbuscular mycorrhizal fungi (AMF), stimulate the growth and diversity of beneficial soil microbes, which allow soil system to maintain stability and resilience under stress conditions, such as drought, salinity and heavy metals (Smith and Read, 2010; Wagg et al., 2014). These microbes contribute significantly to soil aggregation by producing extracellular polysaccharide and glomalin particularly from AMF. These compounds bind soil particles into stable aggregates, thereby improving soil porosity, aeration, and water infiltration, which are vital for healthy root growth and microbial colonization (Rillig, 2004; Yonas and Zawar, 2024). Furthermore, the organic residues and root biomass provided by legumes serves as substrates for decomposition, promoting the formation and stabilization of soil organic matter, this not only enhances the long-term soil fertility but also contribute to carbon sequestration, supporting sustainable agriculture practices (Bhatia, 2008; Sá Pereira et al., 2017). Thus pulses not only enrich soil fertility but also boost soil health by fostering a biological active and structurally sound soil environment. .

Legumes play a significant role in improving soil structure, porosity, and water holding capacity through various mechanisms that enhance soil quality (Kocira et al., 2020). The decomposition of legume residues adds nitrogen-rich organic matter, which enhances the formation of stable soil aggregates. This aggregation is crucial as it creates more pore spaces within the soil, leading to better aeration and reduced soil erosion (Sánchez-Navarro et al., 2019). The protein glomalin, produced by soil microbes in association with legume roots, acts as a “glue” that binds soil particles together, further enhancing aggregate stability and improving soil tilth (Ananda et al., 2022). The deep taproots of many legume species can penetrate compacted soil layers, creating channels that increase soil porosity. This process allows for improved air movement and water infiltration deep into the soil profile. Additionally, the activity of earthworms, stimulated by the nitrogen-rich residues of legumes, contributes to the formation of burrows that enhance soil porosity (Ruiz et al., 2008). Whereas, legumes also improve the water holding capacity of soil by increasing the amount of organic matter present. Higher soil organic matter enhance the soil water retention by improving aggregate stability and enhanced micropores that store plant-available water, which is particularly beneficial in drought-prone areas (Subbarao et al., 1995). The incorporation of legume residues into soil significantly affects its chemical properties such as electrical conductivity (EC), pH, buffer capacity and nutrient dynamics etc. The addition of legume residues has been shown to increase soil pH. For instance, one study reported an increase of up to 0.6 units at Day 0 and 0.7 units at Day 28 after the addition of legume residues at rates of 1.54 and 3.08 g/kg of soil (Yadava et al., 2023). The chemical composition of legume residues also influences the soil’s buffering capacity, which is critical for maintaining stable pH levels during various environmental conditions (Tang and Yu, 1999). The addition of legume residues can influence soil EC, primarily through the release of nutrients during decomposition (Yadava et al., 2023). When legume residues are incorporated into the soil, allelochemicals released from legumes can alter the EC values, particularly when accumulated beyond certain threshold levels. This alteration can affect the soil’s overall chemical balance and its suitability for subsequent crops (LAWONGSA et al., 2018). The rate at which legume residues decompose can vary, influencing how quickly EC levels change. Faster decomposition leads to a more rapid increase in nutrient availability and consequently a quicker rise in EC (Yadav et al., 2015). Legume residues can also enhance the availability of essential nutrients, particularly nitrogen, due to their lower carbon-to-nitrogen (C:N) compared to non-leguminous plants. This quality facilitates quicker decomposition and nutrient release, improving soil fertility (Adetunji et al., 2021).

Intercropping cultivation of two or more crops simultaneously on the same piece of land has re-emerged as a promising approach for advancing sustainable agriculture (Table 2). Among the various intercropping systems, those incorporating pulses (legumes) offer particularly significant benefits. Pulses possess the unique ability to fix atmospheric nitrogen through symbiotic associations with Rhizobium bacteria, thereby enriching soil fertility naturally. This biological nitrogen fixation reduces the reliance on synthetic nitrogen fertilizers, leading to lower production costs and minimizing environmental pollution (Das and Ghosh, 2012). Pulse-based intercropping improves land use efficiency and crop productivity by maximizing the use of available sunlight, water, and nutrients. It also contributes to pest and disease suppression, reduces weed pressure, and provides a more stable income through crop diversification (Agegnehu et al., 2006). Additionally, legumes improve soil structure, organic matter content, and microbial activity, which are essential indicators of soil health (Meena et al., 2018). These systems are especially suitable for smallholder and resource-poor farmers in rainfed and semi-arid regions like South Asia and Sub-Saharan Africa. By contributing

Table 2: Intercropping of Pulses with other crops

to improved food security, income stability, and ecological balance, pulse-based intercropping aligns with the core principles of sustainable agriculture and climate resilience (Pretty et al., 2012).

Leguminous cover crops play a vital role in controlling soil erosion through a combination of ground cover, root stabilization, and enhancement of soil structure. Their dense canopy effectively shields the soil surface from raindrop impact, reducing the detachment and transport of soil particles (Rodríguez et al., 2022). Additionally, the extensive root systems of legumes such as hairy vetch and crimson clover bind soil particles and improve structural stability, especially on sloped or erosion-prone lands (Blanco-Canqui et al., 2015). The incorporation of organic residues from legume biomass contributes to soil aggregation and water infiltration, thereby limiting surface runoff (Kumar et al., 2020a). Furthermore, legumes can provide continuous soil cover during fallow periods or off-seasons, ensuring year-round protection against erosive forces (Obaisi et al., 2022). These characteristics make legumes particularly valuable in conservation agriculture and integrated soil fertility management systems aimed at sustaining long-term soil productivity. Moreover, cover crops reduce soil surface temperatures and evaporation losses by providing canopy cover, effectively shading the soil and preserving moisture (Blanco-Canqui et al., 2015). Legumes also promote deeper rooting in companion or subsequent crops by improving subsoil conditions, which enhances drought resilience.

Unlike pulses, which have a deeper taproot system, cereals have a fibrous root system. As a result, pulses have a greater capacity to endure drought and absorb water from deeper soil, root growth rate, root density, spread, and size are vital responses of pulses under drought stress (Figure 3). A well-developed root system enables pulses to reach water from deeper soil layers, which contributes to their drought avoidance strategy (Turner et al., 2001). Pulses have mechanism of drought tolerance like, several types of pulses grow fast, developing seeds and blooms with little vegetative growth, allowing them to avoid drought. Maturity and early flowering are critical attributes for pulses to survive under water limit conditions (Turner et al., 2001). By preserving a greater tissue water content through stomatal closure, wax formation, limited vegetative growth, and improved water uptake by deep root systems, they are able to endure drought stress (Joshi et al., 2020). By regulating stress-responsive genes and transmission pathways, such as those involving phytohormones, osmolytes, and antioxidant defense systems, tolerance pulses can sustain physiological activity during extreme drought (Petrushin et al., 2023). A “QTL-hotspot” region has been identified in chickpea that is linked to 12 QTLs that control multiple drought tolerance traits, including yield under drought stress (YLD), seed weight under drought (SWD), relative water content (RWC), and membrane stability index (MSI) (Yonas and Zawar, 2024). Some pulses in dry conditions, may reduce water loss by enclosing their stomata, resulting in water conservation (Khatun et al., 2021). During dry spells, they can store solutes like proline to keep their osmotic balance intact and avoid themselves from losing water (Dutta et al., 2018). Under stress conditions many of the plants loss their water throughout stomata opening, but pulses has the ability to close their stomata, closes the door for Co2 and store water for stress limit condition this help them to survive for some period (Turner et al., 2001). They have defense system to mitigate stresses, drought one of them so they have antioxidant enzyme such as super peroxide dissimulate (SOD), catalase (CAT), ascorbate peroxidase that helps them to neutralize the ROS (Patel and Hemantaranjan, 2012). Likewise, they also accumulate glutathione and proline, which act as antioxidants and help maintain cellular redox equilibrium (Talukdar, 2016). Some pulse has phenotypic plasticity, which allows them to modify their morphology and physiology in response to changing environmental conditions, like as drought (Hall, 2012). The antioxidant system in them has a close relationship to the redox regulatory network, which helps regulate ROS levels and maintain cellular homeostasis (Nadarajah, 2020). Drought avoidance mechanism, they restrict transpiration to prevent water loss during drought conditions. This reduction helps preserve water and maintain adequate water levels within the plant (Subbaramamma et al., 2017). So by reduction in transpiration the water use efficiency and uptake water from root zone under stress condition, some of them have naturally mechanism to avoid drought stress by preserving water from root zone and do minimum losses of water by closure of stomata (Nadeem et al., 2019).

Water requirement of pulses as against the major crops are low because of their deep root system that’s allow them to access water from deeper soil layers (Ray et al., 2023). The main difference between pulses and major crops water requirement is of canopy development, pulses develop their canopy slower than other crops like wheat, cotton, sugarcane and rice they are faster in developing canopy, at the end water requirement increased (Ouda et al., 2016). As showed in Figure 4.

Legumes offer significant economic benefits to farming systems by reducing input costs, enhancing productivity, and providing diverse market opportunities. One of their primary contributions is through biological nitrogen fixation, which minimizes the need for synthetic nitrogen fertilizers a major cost factor in crop production (Kebede, 2021). This not only lowers production expenses but also contributes to long-term soil fertility, reducing future input requirements. Additionally, legumes often serve as dual-purpose crops, providing both grain and fodder, thereby diversifying farm income and improving resilience to market fluctuations. In intercropping or rotational systems, legumes can increase overall land productivity and stabilize yields, leading to higher economic returns per unit area (Mucheru-Muna et al., 2010). Moreover, many legumes such as soybeans, chickpeas, lentils, and mung beans have growing domestic and export markets, especially due to rising demand for plant-based proteins. These characteristics make legumes an economically sustainable choice, especially for smallholder farmers seeking cost-effective, climate-resilient, and market-responsive cropping strategies.

Pulses play a pivotal role in promoting sustainable agriculture through their multifaceted contributions to soil health, climate resilience, and economic stability. Their unique ability to biologically fix atmospheric nitrogen reduces dependency on synthetic fertilizers, thereby enhancing soil fertility and lowering production costs. Intercropping and rotation systems involving pulses improve land-use efficiency, suppress weeds and pests, and increase biodiversity, making these systems particularly beneficial for resource-constrained and rainfed farming environments. Furthermore, pulses exhibit significant drought tolerance mechanisms, including deep rooting systems, osmotic regulation, antioxidant defense, and stomatal control, making them highly suitable for cultivation in arid and semi-arid regions. Their ability to function as cover crops and green manures also helps prevent soil erosion, enhances organic matter content, and improves the physical, chemical, and biological properties of the soil. Economically, pulses contribute to input savings, yield stability, income diversification, and access to growing domestic and international markets. Overall, integrating pulses into cropping systems represents a sustainable and climate-smart strategy that supports food security, soil regeneration, and rural livelihoods. Expanding their cultivation and adoption is critical to meeting future agricultural and environmental challenges.

This review uniquely consolidates the nutritional, soil-regenerating, drought-resilient, and erosion-control benefits of pulses into a unified climate-smart agriculture framework. It emphasizes pulse cultivation as a practical strategy to reduce fertilizer dependence, improve soil health, and strengthen sustainable food production under climate stress.

Shoaib Zawar: Writing, conceptualization, data curation and investigation.

Muhammad Waqas Yonas: Helped in data curation, investigation and writing.

Muhammad Mujahid Akbar: Helped in investigation and writing.

Mudassir Aziz: Critical review and helped in writing.

Muhammad Ibrahim: Helped in investigation

Taha Ishfaq: Helped in investigation

This research did not receive any specific funding or grant from agencies in the public, commercial, or not-for-profit sectors. The literature review and article analysis conducted did not have any external financial support or sponsorship.

The authors declare that no generative AI and AI assisted technology was used in the creation of this manuscript.

All the authors have no conflict of interest.