Constraints faced by farmers in the adoption of green manure crops and their suggestions for promoting sustainable agriculture

Introduction

Green manuring is one of the oldest soil fertility management practices and has historically been associated with fallow-based crop rotations. Ancient records indicate its early use in China around the 12th century B.C., and later in Greece and Southern Europe where crops such as lupines and fiber beans were utilized to improve soil fertility. Green manuring refers to the practice of incorporating green plant biomass into the soil while the crop is still succulent, primarily to enrich the soil with organic matter and nutrients. The value of green manuring lies in the incorporation of organic matter into the soil, which is fundamental to maintaining true soil fertility (Valizadeh et al., 2023) [13] . In recent years, organic nutrient sources such as green manure crops have gained renewed attention due to increasing environmental concerns and the need to reduce input costs associated with synthetic fertilizers (Pappa et al., 2006) [7] . Green manure crops, particularly legumes, play a significant role in enhancing soil fertility through biological nitrogen fixation. It has been estimated that a 40-5 day-old green manure crop can contribute approximately 80-100 kg N ha⁻¹ and even if only half of this nitrogen becomes available to the succeeding crop, it can effectively replace 50-60 kg fertilizer N ha⁻¹ (Sharma et al., 2013) [10] . Crops such as Dhaincha, sunhemp, mungbean and guar grown during the kharif season have been reported to produce 8-21 tonnes of green biomass and contribute 42-95 kg N ha⁻¹, while Khesari, cowpea and berseem cultivated during the Rabi season can supply 12-29 tonnes of green matter and 67-68 kg N ha⁻¹ (Mishra & Nayak, 2004) [6] . Green manuring improves soil physical, chemical and microbial properties, enhances biodiversity, and increases crop yield potential (Singh et al., 2022) [12] . Furthermore, legume green manure crops release organic acids, amino acids, carbohydrates, vitamins and mucilage during growth and decomposition, which substantially influence soil health and are considered essential components of sustainable agriculture (Irin & Biswas, 2022; Shukla et al., 2011; Laishram et al., 2020) [3,11,5] . The incorporation of green manure crops is also recognized as an important strategy for soil remediation and sustainable land use, particularly in salt-affected soils (Wong et al., 2019) [14] . Despite these documented benefits, the adoption of green manuring has declined in many regions due to increasing pressure for food production, competition from more profitable crops, and the widespread availability of chemical fertilizers. Continuous cropping and intensive agricultural practices have contributed to the depletion of soil organic matter and declining soil productivity (Salahin et al., 2013; Reddy et al., 2022) [9,8] . The reduction in soil organic matter adversely affects soil structure, water-holding capacity and cation exchange capacity, thereby limiting nutrient availability and mineralization (Abdulraheem et al., 2012; Bonini and Alves, 2010) [1,2] . However, renewed concern over soil fertility degradation and energy conservation has led to a resurgence of interest in green manures among both organic and low-input farming systems (Kumar et al., 2014) [4] . Green manuring has been shown to improve soil physical and biochemical properties, reduce nutrient losses through leaching, and enhance water-holding capacity (Pandey et al., 2008). Although green manuring offers considerable agronomic and environmental benefits, its adoption is not universal. Practical challenges such as limited awareness, seed availability, management constraints, and competition with main crops may hinder its widespread use. Given its recognized contribution to sustainable agriculture, it is essential to understand the constraints faced by farmers in cultivating green manure crops and to document their suggestions for improving adoption. Therefore, the present study entitled "Constraints Faced by Farmers in the Adoption of Green Manure Crops and Their Suggestions for Promoting Sustainable Agriculture" was undertaken to systematically analyse the barriers affecting adoption and to generate farmer-driven recommendations for strengthening sustainable soil fertility management practices.

Methodology

The present study was conducted in Navsari district of South Gujarat. Navsari district was randomly selected for the study. The district comprises six talukas, out of which two talukas, namely Jalalpore and Gandevi, having a higher number of green manuring growers, were selected purposively to ensure adequate representation of respondents practicing green manuring. From each selected taluka, five villages were selected randomly. From each selected village, twelve green manuring growers were selected randomly. Thus, a total of 120 green manuring growers constituted the sample for the present investigation. Thirteen independent variables and one dependent variable were selected for the study in accordance with the objectives. An interview schedule was developed based on the study objectives and relevant literature. The schedule was pre-tested in a non-sample area, and necessary modifications were made to ensure clarity and content validity. Data were collected through personal interviews conducted at the respondents' farms.

Measurement of Constraints

The constraints faced by farmers in the adoption of green manuring were measured using a structured list of identified constraints. Respondents were asked to indicate whether they experienced each constraint. The responses were recorded in dichotomous form (Yes/No). Frequency and percentage were calculated for each constraint, and the constraints were ranked in descending order based on percentage values.

Measurement of Suggestions

Farmers were also requested to offer suggestions to overcome the constraints faced in the adoption of green manuring. The suggestions were compiled, categorized, and analysed using frequency and percentage. Ranking was done based on the percentage of respondents suggesting each measure.

Development of Extension Strategy

The extension strategy to overcome constraints was developed through triangulation of (i) constraints reported by farmers (ii) suggestions given by farmers (iii) consultation with subject matter experts and extension personnel. Based on this triangulated approach, strategic measures and responsible executing agencies were identified.

Statistical Analysis

The collected data were coded, tabulated, and analysed using appropriate statistical tools such as frequency, percentage, mean and ranking techniques in accordance with the objectives of the study.

Results and Discussion

Constraints Faced by Green Manuring Growers

The respondents were requested to indicate the constraints faced by them in the adoption of green manuring practices for sustainable agriculture. Frequency and percentage were calculated for each identified constraint, and the constraints were ranked based on the descending order of percentage. The results are presented in Table 1. The data presented in Table 1 reveal that the major constraints faced by farmers in the adoption of green manuring were: unavailability of labour (Rank I), lack of a positive mindset toward green manuring practices (Rank II), unavailability of seed at the proper time (Rank III), shortage of irrigation facilities (Rank IV), higher cost of cultivation of green manuring as compared to the use of FYM or other manures (Rank V), lack of systematic training on green manuring (Rank VI), and pressure to follow only traditional farming practices from elder family members (Rank VII). Seek their suggestions for developing the extension strategy for enhancing the knowledge level of green manuring growers An attempt was made to elicit suggestions from farmers to overcome the constraints faced in the adoption of green manuring. The respondents were requested to provide their suggestions to address the difficulties encountered in practicing green manuring. The data collected were compiled, analysed using frequency and percentage, and the results are presented in Table 2.

The findings presented in Table 2 indicate that the major suggestions provided by farmers to overcome constraints in green manuring adoption were: adoption of farm mechanization (Rank I), timely and adequate training on green manuring practices (Rank II), timely supply of green manure seeds at reasonable prices (Rank III), provision of irrigation facilities at subsidized rates (Rank IV), reduction in the cost of cultivation compared to FYM and other manures (Rank V), provision of technical know-how regarding green manuring and efficient use of farm resources (Rank VI), and modification of traditional farming practices to incorporate improved techniques (Rank VII).

Conclusion

The findings of the present study clearly indicate that although green manuring is a valuable practice for improving soil fertility and promoting sustainable agriculture, its adoption among farmers is constrained by several practical and socio-economic factors. The major constraints identified were unavailability of labour, lack of a positive mindset toward green manuring practices, unavailability of seed at the proper time, shortage of irrigation facilities, higher cost of cultivation compared to FYM and other manures, lack of systematic training, and resistance to change due to adherence to traditional farming practices. These constraints highlight that both resource-related and behavioural factors significantly influence adoption. Farmers also provided practical suggestions to overcome these barriers. Promotion of farm mechanization, timely and adequate training, provision of quality seeds at reasonable prices, subsidized irrigation facilities, reduction in cost of cultivation, technical guidance, and encouragement to adopt improved practices were identified as important measures. The triangulated extension strategy developed from farmers' responses and expert consultation emphasizes institutional support, capacity building, input accessibility, and policy interventions.

Acknowledgement

The authors sincerely acknowledge the support and guidance provided by the Department of Agricultural Extension and Communication, Navari Agricultural University, Gujarat, for facilitating the conduct of this study. The cooperation extended by the farmers and field functionaries during data collection is gratefully acknowledged.

Disclaimer (Artificial intelligence)

The author(s) hereby declare that generative AI technologies, such as OpenAI ChatGPT version 4, have been used during the writing or editing of manuscripts for language improvement.

Author Conflict

Authors have declared that no competing interests exist.

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