Conception of Improved Blackgram (Vigna mungo L.) Production Technology and its Propagation among Farmers for the Development of a Sustainable Seeds Production Strategy

Abstract

Having a strong seed system that could spur agricultural expansion would be the first and most important step toward achieving food security in the nation of India. The main objective of this study was to investigate the impact of Improved Production Technology (IPT) on the production of high-quality seeds of blackgram (Vigna mungo L.) cultivar VBN 6 in a farmer-participatory mode in Tamil Nadu, India’s Ponnanaiyar subbasin during kharif and rabi 2017–18. In total, 985 farmers from 235 places throughout chosen Pudukkottai and Tiruchirappalli districts received frontline IPT demonstrations and IPT was applied in their agronomic practices afterwards. Compared to traditional approaches, our study demonstrated that IPT not only facilitated the production of high-quality seeds, but also a 25.14% higher seed yield of blackgram. Furthermore, the average water productivity was improved from 0.116 kg ha⁻¹ m⁻³ to 0.154 kg ha⁻¹ m⁻³. This study indicated IPT was effective in guaranteeing a system of sustainable seed production and thus was of great value in raising the farmers’ net incomes, profitability, and cost-benefit ratios. There is little well-documented data on how the farmer-participatory approach improves seed production technology in a sustainable way in the case of pulses when adopting improved production technologies in arable crop farming. Our creative method of having farmers participate in the demonstrations allowed us to evaluate how these extension programs affected the technology utilized to produce high-quality seeds. This study indicated IPT was effective in guaranteeing a system of sustainable seed production and thus was of great value in raising the farmers’ net incomes, profitability, and cost–benefit ratios.

1. Introduction

Pulses constitute a major source of protein for the majority of the population in India, which is predominantly vegetarian in dietary habits. India contributes 25–28% of the total global pulse production, and it is the largest producer and consumer of pulses in the world. In total pulse production, chickpea stands first with 48%, followed by redgram with 17%, blackgram with 10%, and greengram with 7%. The remaining quantity is contributed by other pulses. During the last decade, the productivity of blackgram has significantly increased from 405 kg ha⁻¹ in 2007–08 to 778 kg ha⁻¹ in 2020–21. In India during 2022, blackgram was cultivated in an area of 4.63 million hectares with a production of 2.78 million tons, resulting in a productivity of 987 kg ha⁻¹ [1]. This productivity gain could be attributed to improved cultivars and the use of inputs, mainly in South India and especially in Andhra Pradesh and Tamil Nadu. India is currently importing approximately 3 to 4.5 million tons, and the projected requirement for 2030 is 32 million tons, which requires a growth rate of 4.2%. The majority of the pulse-cultivated area falls under rainfed, resource-poor, and harsh environments frequently prone to drought and other abiotic stress conditions, resulting in low productivity [2]. Blackgram is one of the major sources of protein among vegetarians in India. It contains 22–24% protein and plays an important role in crop rotation, intercropping, and maintaining soil fertility through converting atmospheric nitrogen into organic nitrogen, which is then available to subsequent crops.

Seed is the first link in the food production chain, and it is the foundation of agriculture. Food security is mainly dependent on crop production, and population projections confirm that agriculture will need to feed 9 billion people by 2050. Of the several factors vital for enhancing the production and productivity of crops, seed (a living product that must be grown, harvested, and processed appropriately to make the best use of its viability and consequent crop productivity) is a vital factor for ensuring sustainable agriculture [3]. Seeds serve as a fundamental input in all crop production, playing a pivotal role in global food security, rural development, farmers’ livelihoods, and the sustainability of green value chains. The definition of ‘good seed’ varies based on each farmer’s specific requirements, making the sustainable availability of seeds and freedom of choice regarding seeds a crucial concern for every farmer. It is a basic requirement for every planting season and crucial for ensuring food security [4]. The cultivation area for pulses has been steadily increasing each year, and yet there is a shortage of quality seeds for planting, primarily due to insufficient seed production acreage. Improving seed yield and quality necessitates the adoption of specific agronomic practices and advanced techniques in seed production [5]. Approximately 80% of seeds worldwide are sourced through the informal seed system, primarily saved by farmers [6,7,8], which leads to poor yield. However, the quality of seeds is crucial for a successful start [9,10].

The potential production of any crop is largely determined by the quality of the seed. The quality of the seed is mainly dependent on several factors, which start with the growth of mother plants, agronomic maintenance of the plants during the complete growth stages of crops, proper harvesting, processing of harvested products, storage of seed materials, ensuring their viability until planting, etc. Deterioration in seeds can happen due to adverse environmental factors, which will result in a loss of seed vigour and viability and ultimately a loss of seed quality. Biotic factors that influence seed quality are atmospheric temperature (maximum, minimum, and average), relative humidity (RH), moisture presence in the seeds (%), damage caused to the stored seeds by insect pests, including pathogens and microorganisms, etc. A seed is said to be unviable if it is unable to restart its active growth after hydration [11].

In agricultural production, seed quality is ensured by having genetic purity, physical purity, good germination percent, and optimal moisture content, being seed-borne pathogen-free, weed seeds being excluded, having no damage caused by insects or any physical means, and including no other inert materials. The potential productivity of any crop can be realized if seed quality is ensured, which is evident from precision farming projects in which quality planting materials are ensured apart from drip fertigation [12]. Since good planting material will result in proper germination, ensuring the plant population has initial vigour, vigorous growth results in less infestation by weeds, ultimately contributing a more than 20–25% increase in crop productivity [13,14]. However, availability of quality seed of improved varieties and hybrids is grossly inadequate and is one of the major constraints for enhancing production and productivity [15,16].

Some earlier studies showed constraints in the seed production cycle because of high production costs, failures in logistics, problems in demand (anti-cyclic), etc. [17,18]. In addition, it is a usual practice that farmers may not purchase seed from formal seed sources since they are resource poor, lack financial support, and have low risk-taking capacity. In the agricultural production system, usually the criteria followed to develop improved varieties are based on a formal expert system with the breeder’s assistance, and this results in good-quality seed which will result in higher productivity and profitability. For faster and sustainable agricultural development, a farmer-participatory approach is essential. To ensure good quality of seed produced by the informal seed sector, capacity enhancement of all those involved in seed production, processing, and distribution is essential. Training in Integrated Crop Management (ICM) and seed production technology has enhanced famers’ knowledge and skills, which prepared them well for taking up quality seed production and consequently acquiring more profit from pulse seed production. In addition to monetary benefits, farmers also developed a culture and concept of “work together through the formation of cooperative societies,” which enhanced their bargaining power in the market [19].

Seed quality standards and policies are derived based on this paradigm. It is well established and known that these steps being followed in the formal seed system chain, i.e., agricultural researchers, has resulted in improved varieties with high yield potential, low degeneration potential of seed, and the avoidance of false or low-quality seeds. However, as mentioned earlier, farmers will look for yield stability, resistance to biotic and abiotic stress (resilience), local performance, and low input. As a result, both these systems (formal and farmer seed production systems) never coincide with each other for maximum production. Since normally seed of local varieties is not available from the formal sector, the main option for farmers is to use the available varieties’ seed, some of which may not be of improved hybrid varieties. In such instances, the experts in the formal sector will have to play a role in supplying quality seeds to the farmers, and their decisions are decided by cost, availability, and accessibility to the markets [17]. Farmer-managed seed systems have the advantage of being responsive to local needs and preferences while contributing to the maintenance of crop diversity on the farm and in local communities [20]. This is essential for seed and food security [21]. A traditional seed system governed by local farmers is crucial for sustainable food production, balanced nutrition, and maintaining genetic diversity under marginal environments [22]. The quality seed of improved, farmer-preferred varieties contributes to improved agricultural productivity as it responds to farmers’ needs and situations. The authors of [23] conceptualized farmer-level seed security as a situation in which a farmer has access to sufficient quantities of seeds of their preferred varieties with desired physical qualities.

In India, farmer-participatory seed production stands out as one of the rare instances [24] where the seed sector has progressed alongside agricultural productivity. Quality seeds of improved varieties favoured by farmers play a vital role in boosting agricultural productivity by meeting farmers’ specific needs and conditions [25]. Over the past decade, numerous varieties and hybrids across different field crops have been developed, demonstrating a yield superiority ranging from 10% to 40% over local cultivars. Farmer-level seed security is achieved when farmers have ample access to seeds of their preferred varieties with desired traits [26]. However, small-scale farmers face numerous challenges, including biotic and abiotic stresses, which jeopardize village-level seed sufficiency [27].

Therefore, there is a need for substitution to ensure the availability of quality seed of improved varieties at the village level and for the integration of farmers in the seed production and supply systems to enable timely availability of quality seed at the door-step of farmers [28]. An immediate increase in the productivity and production of crops can be achieved by a higher distribution of quality seeds of new and high-yielding varieties. In this context, the concept of a farmer-participatory mode of seed production that advocates village self-sufficiency in the multiplication and distribution of quality seeds is gaining momentum. The formal seed sector, with its expertise, helps in the demonstration and propagation of the latest, novel, and user-friendly technologies to the farming community, along with the supply of good-quality HYVs (high-yielding varieties) and hybrids, which assist in enhancing the crop productivity of major crops [3]. However, for a sustainable and economically viable seed production system, it is necessary that farmers are trained in and follow integrated crop management (ICM) and seed production, processing, and safe storage technologies. Different models for organizing seed production have developed over time, depending on the crop, variety, commercial value, and quality standards used. These include farmers’ own seed production, centralized certified seed production, and, more recently, different models for decentralized seed production [29].

In order to have an effective seed production link, agricultural universities and seed-producing firms should take care in the production of nucleus and breeder seeds. Foundation seed production showed a consistent increase during the XI plan, with an 81.4% increase over the first year of the XI plan [3]. By considering all the points discussed above and bringing farmers into the seed production chain, a demonstration of IPTs for the production of quality blackgram seeds under a farmer-participatory approach in the Ponnanaiyar subbasin in the Pudukkottai and Tiruchirappalli districts of Tamil Nadu was attempted.

2. Materials and Methods

The present study was conducted to demonstrate the improved varieties and production of quality blackgram seeds under farmer-participatory approaches in the Ponnanaiyar subbasin in the Pudukkottai and Tiruchirappalli districts of Tamil Nadu state, India. Details about the districts are presented in

Table 1. Basic information of the Pudukkottai and Tiruchirappalli districts.

Geographical Position	Pudukkottai	Tiruchirappalli
North latitude	9°50′ and 10°40′	10°15′ and 11°20′
East longitude	78°25′ and 79°15′	78°10′ to 79°50′
Total Geographical area (Sq km)	4663.29	4403.83
Rainfall pattern
SW monsoon (June–September) (mm)	350.6	293.7
NE Monsoon (October–December) (mm)	406.2	391.5
Winter (January–February) (mm)	33.1	22.7
Summer (March–May) (mm)	97.5	109.9
Total	887.4	817.8

. The demonstration was funded by the World Bank under the Tamil Nadu Irrigated Agriculture Modernization Project. A total of 235 demonstrations in an area of 150 hectares were conducted on farmers’ fields in 24 villages, comprising 5 blocks: Thirunallur, Kothirapatti, Eswarankovil, Kattakudi, and Punginipatti villages of the Annavasal block; Mandaiyur, Kalkudi, Thennampadi, Kudumbaloor, Avoor, Theravoor, Sooriyur, Perambur, Velur, and Kathalur villages of the Viralimalai block of Pudukkottai; Poongudi, Tayanur, Senguruchi, Esanapatti, and Navalurkuttupattu villages of the Manikandam block; Navalpattu village of the Thiruverumbur block; and Samudram, Sevalur, and Pannapatty villages of the Manapparai block, all of the Tiruchirappalli district in Tamil Nadu, during kharif and rabi seasons 2017–18 in irrigated conditions. Details are provided in

Table 2. Total area and beneficiaries (number of farmers) covered, block-wise (in ha), in Ponnanaiyar.

Name of the Block	Target (2017–2018)
	Area (ha)	Beneficiaries (Numbers)
Annavasal	44.0	82
Viralimalai	64.0	86
Thiruvarambur	12.8	14
Manikandam	13.2	21
Manapparai	16.0	32
Total	150	235

, and these demonstrations were conducted with a plot area of 0.4 ha and a nearby area of 1.0 ha with farmer management practices as controls.

Generally, seed production locations were identified based on the soil, climate, irrigation resources, and transportation facilities to the destination. For individual farmers who are taking up a seed production programme and supplying the seed produce to distant places, processing and packing is difficult. Therefore, many seed growers joined together to encourage and economise their activities though a community approach in the purchasing of basic seed, getting technical information, facilitating the field visits, and transporting the seed produce to the destination. After identifying the potential area and farmers for seed production, group meetings with progressive farmers’ groups were conducted to discuss the crop variety to be taken up, season, seed production techniques, and critical stages for adopting interventions to maximize the seed yield [30].

In order to ensure efficient and effective quality seed production, farmers were trained in various aspects of seed production technology. These included registration of seed production plots, varietal descriptions, seed treatment and sowing methods, weed management, water management, integrated nutrient and soil management, integrated insect pest and disease management, including biological control methods, the maintenance of isolation distance rogueing in seed production plots, identification of the physiological maturity stage for the harvesting of seed crop, postharvest seed management technology, and value addition [31].

The physical and chemical properties of the soils at these demonstration sites, along with the climatic conditions, are provided in

Table 3. Physical and chemical properties of soil.

Particulars	Pudukkottai	Tiruchirappalli
A. Mechanical analysis
Sand (%)	23.70	23.00
Silt (%)	22.10	21.00
Clay (%)	54.20	56.00
Textural classification	Sandy clay loam	Sandy clay loam
B. Chemical analysis
Available N (kg ha−1)	228.0	120.4
Available P2O5 (kg ha−1)	14.6	32.0
Available K2O (kg ha−1)	120.0	208.0
Organic carbon (%)	0.41	0.32
pH	7.64	8.5
EC (dSm−1)	0.03	0.21
C. Climate condition of study area
Seasonal rainfall (mm) (During crop period)	192.5	195.0
Number of rainy days	7	9
Minimum (°C)	20.5	21.06
Maximum (°C)	39.4	41.2

.

Overview of Study Area in Ponnanaiyar

The Ponnanaiyar subbasin comes under the Cauvery River basin. It has 10,375.94 ha of ayacut area, which consists of anicut, tanks, and direct ayacut. This subbasin consists of six blocks: Manapparai, Vaiyampatti, Manikandam, and Tiruverumbur in the Tiruchirapalli district and Viralimalai and Annavasal in the Pudukkottai district. This basin has 87 non-system and system tanks, 15 channels, and 14 anicuts (Figure 1). The Ponnanaiyar subbasin is mostly covered with sandy loamy or sandy clay loam soil with a nutrient status of being low in nitrogen, medium in phosphorus, and high in potassium (Table 3).

The improved production technologies (IPTs), viz., the high-yielding cultivars of blackgram VBN 6 with quality seeds, were used. The duration of the blackgram VBN 6 is 65 to 70 days and the average yield ranges from 600 to 890 kg ha⁻¹. It is resistant to the Mungbean Yellow Mosaic Virus (MYMV) and has synchronized pod maturity. A seed rate of 15–20 kg ha⁻¹ was used, with seeds sown in rows to ensure the recommended row spacing of 30 cm and a plant-to-plant spacing of 10 cm. Consistently, thinning at 10 DAS was undertaken to alleviate the adverse effects of excessive plant density, thus fostering optimal crop growth and yield. This strategy aims to maintain an ideal plant population of 33 plants per square meter. Seed was treated with Imidacloprid at 5 g kg⁻¹ and carbendazim at 2 g kg⁻¹ of seed 24 h before sowing or with a talc formulation of Pseudomonas fluorescens at 10 g kg⁻¹ seed. Finally, seeds were treated with a biofertilizer with Rhizobium culture CRU-7 at 600 g ha⁻¹ along with Phosphobacteria at 600 g ha⁻¹, which was developed at the Tamil Nadu Agricultural University (TNAU) using rice kanji as a binder. Irrigation was achieved through the beds and channel method and weed management through pre-emergence herbicide with Pendimethalin at 3.3 L ha⁻¹ applied at 3 days after sowing (DAS) with 500 L of water, as well as early post-emergence herbicide with Imazethapyr at 500 mL ha⁻¹ and Quizalofop ethyl at 1000 mL ha⁻¹ applied with 500 L of water at 18 DAS using a hand sprayer.

Inorganic fertilizer was applied in blanket doses of 25 kg Nitrogen + 50 kg Phosphorus + 25 kg Potash + 20 kg Sulphur ha⁻¹_, as per the standard recommendation. Sulphur was applied in the form of gypsum if Single Super Phosphate was not applied as a source of phosphorus. Micronutrients, viz., application of Zinc sulphate at 25 kg ha⁻¹ under irrigated conditions, were applied as basal. For yield improvement through increasing physiological and biochemical attributes, a foliar spray of Di ammonium phosphate (DAP) 2% on 30 and 45 DAS or TNAU pulse wonder at 5 kg ha⁻¹ at 50% flowering was adopted. Pheromone traps were set up at 12 traps ha⁻¹ against Spodoptera litura and the activity of the pest was monitored to synchronise the pesticide application. Sprayed Imidacloprid at 150 mL ha⁻¹ or Dimethoate at 500 mL ha⁻¹ against MYMV and leaf crinkle disease were adopted for blackgram seed production.

The scientists were involved in providing technical guidance and continuous monitoring for assuring seed quality. Further, farmers’ skills on seed treatment, weed control, nutrient management, maintenance of genetic purity through adoption of isolation distance, vigorous roguing, harvesting at the physiological maturity stage, threshing, and post-harvest handling were imparted through method demonstration and capacity-building programmes. For procurement of seeds produced by farmers, a buy-back arrangement was made to purchase the seed by the institute on satisfaction of the quality of the seed at a 20% higher rate than the prevailing Minimum Support Price [30].

In farmers’ practices, local blackgram cultivar was used at a seed rate of 25 kg ha⁻¹ with a broadcasting seed sowing method. Plant populations were not uniform and varied from 19–26 per square meter, the flood method of irrigation was followed, no seed treatment was practiced, and pre-emergence herbicide of Pendimethalin at 2.0 L ha⁻¹ was applied at 3 DAS, with no farmyard manure (FYM) and indiscriminate application of inorganic fertilizer. No thinning and gap filling, no foliar nutrient spray, and no plant protection measures for the control of pests and diseases were followed by farmers (

Table 4. Details of farmers’ practices and Improved Production Technologies (IPTs) followed in the Ponnanaiyar subbasin under a farmer-participatory seed production programme.

Sl. No.	Cultural Operation	Farmers’ Practices	Improved Production Technologies
1.	Cultivar	Local cultivar	VBN 6
2.	Seed rate (kg ha−1)	25	15–20
3.	Seed quality	Ungraded seed	Graded seed
4.	Seed treatment	No seed treatment	Imidacloprid at 5 g kg−1, carbendazim, or Thiram at 2 g kg−1 of seed 24 h before sowing (or) with talc formulation of Pseudomonas fluorescens at 10 g kg−1 seed. Finally, seeds were treated with biofertilizer with Rhizobium culture CRU-7 at 600 g ha−1 along with Phosphobacteria at 600 g ha−1
5.	Method of sowing	Broadcasting	Line sowing
6.	Plant population (No. m−2)	19–26	30–33
7.	Fertilizer application	Indiscriminate application	Soil test-based Integrated Nutrient Management
8.	Weed management	Only pre-emergence herbicide of Pendimethalin at 2.0 L ha−1 applied at 3 DAS	Application of pre-emergence herbicide of Pendimethalin at 3.3 L ha−1 applied at 3 DAS with 500 L of water and early post-emergence herbicide of Imazethaphr at 500 mL ha−1 and Quizalofop ethyl at 1000 mL ha−1 applied with 500 L of water at 18 DAS using hand sprayer.
9.	Water management	Flood method with excess irrigation/Indiscriminate application	Need based irrigation in once in 10 days interval
10.	Application of foliar nutrient	No foliar nutrient spray	TNAU pulse wonder @ 5 kg ha−1 applied at flower initiation stage
11.	Plant protection	No plant protection measures for control of pest and disease	Integrated pest management: spraying of Dimethoate and Chlorantraniliprole

).

Blackgram yield attributes and yield were recorded at the time of harvesting. After harvest, the seeds were cleaned, processed, and sent to a seed testing laboratory for seed quality testing. Further, a tetrazolium test was also conducted to confirm the viability of the seeds. The seeds passing the quality parameters were treated with carbendanzim at 2 g kg⁻¹ of seed to prolong storability and packed in gada cloth bags (capacity of 8 kg per bag). The seed bags were affixed with labels which contained the name of the crop, variety, quantity of seeds, date of test, date of packaging, validity period, and seed quality parameters, viz., germination percentage, percent of pure seeds, inert matter, other crop seeds, weed seeds, moisture percent, genetic purity, etc. The blackgram seeds produced under IPT were sold at Rs. 75 kg⁻¹, and the grain of blackgram that was produced under farmers’ practices was sold at Rs. 50 kg⁻¹. The seed-producing farmers were linked with the Certification Agency for seed certification and public sector seed agencies, such as the National Seeds Corporation Ltd. (NSC, Ltd.), State Farms Corporation of India (SFCI), and Krishi Vigyan Kendra (KVK), to strengthen the formal seed sector for pulse seed production. All stakeholders (farmers, seed-producing agencies, Department of Agriculture (DoA), and KVK staff and other district-level officials) were invited for promotional and awareness activities, such as diagnostic field visits, field days, and participatory evaluation visits, which were organized on a regular basis to develop functional linkages [30].

Water productivity usually defined as the quantity of water used for crop production, and it is calculated as follows:

Water Productivity (kg ha⁻¹ m⁻³) = Yield (kg ha⁻¹)/Water Used (m³)

(1)

It is normal to represent WP in units of kg ha⁻¹ m⁻³. In the current study, production was quantified in kg ha⁻¹, and the quantity of water used was accounted for as millimetres (mm) of water applied for irrigation or received as rainfall during the growing season in m³ ha⁻¹ [32]. The farmers were encouraged to adopt the recommended package of practices for quality seed production, realizing higher returns and water productivity.

Data concerning seed yield from front line demonstrations FLD plots and from fields cultivated following local practices adopted by the farmers of the area were collected as per the standard procedure and evaluated. The potential yield of 890 kg ha⁻¹ was taken into consideration based on the standard plant population (333,333 plants ha⁻¹) and the average yield as prescribed for the variety [33], which were used for gap analysis, technology index, and calculating the economic parameters of blackgram. The details of different parameters and formulas adopted for analysis are as follows:

Extension gap = Demonstration yield − Farmers’ practice yield

(2)

Technology gap = Potential yield − Demonstration yield

(3)

Technology index = Potential yield − Demonstration yield/Potential yield × 100

(4)

Additional cost (Rs.) = Demonstration cost (Rs.) − Farmers’ Practice cost (Rs.)

(5)

Effective gain = Additional Returns (Rs.) − Additional cost (Rs.)

(6)

Additional returns = Demonstration returns (Rs.) − Farmers’ practice returns (Rs.)

(7)

Incremental B:C ratio = Additional Returns/Additional cost

(8)

3. Results and Discussion

3.1. Yield Attributing Traits

The results revealed that maximum numbers of blackgram pods per plant, number of seeds per pod, and 100 grains weight (38, 6, and 3.89) were recorded for IPT as against farmers’ practices (29 pods per plant, 5.4 seeds per pod, and 3.71 g of 100 grains weight) (

Table 5. Yield attributing traits of blackgram (mean value of 235 site).

Yield Characters	Improved Production Technologies	Farmers’ Practices
i. No. of pods/plant	38.0	29.0
ii. No. seeds/pod	6.0	5.4
iii.100 grain weight	3.89	3.71
iv. Seed yield (kgha−1)	719	642
Water consumed (mm ha−1)	426	473

). The improper management of blackgram in farmers’ practices led to lower numbers of pods per plant, seeds, and 100 grains weight as compared to the IPT method.

3.2. Seed Yield

The seed yield productivity of blackgram under IPT yield ranged between 700 and 828 and between 637 and 743 kg ha⁻¹ in the Annavasal and Viralimalai blocks of Pudukkottai district, and from 529 to 596, 487 to 675, and 587 to 754 kg ha⁻¹ in the Manikandam, Thiruverumbur, and Manapparai blocks of the Tiruchirappalli district, respectively (

Table 6. Influence on IPT for seed production on minimum, maximum, and mean yields of blackgram, village-wise, of farmers’ fields.

Name of the Block/Village	Yield (kg ha−1)						% of Increased Yield over Farmers’ Practices (%)
	IPT			Farmers’ Practices
	Minimum	Maximum	Mean	Minimum	Maximum	Mean
Pudukkottai District
(a) Annavasal
Thirunallur	687	762	726	501	565	547	25
Kothirapatti	687	813	766	519	644	595	22
Eswarankovil	687	963	760	515	773	583	23
Kattakudi	662	803	722	490	622	542	25
Punginipatti	776	801	790	602	620	611	23
Average	700	828	753	525	645	576	23.6
(b) Viralimalai
Mandaiyur	612	720	668	441	559	496	26
Kalkudi	662	762	710	482	586	534	25
Thennambadi	662	793	731	482	629	563	23
Kudumbaloor	555	741	647	407	573	487	25
Avoor	645	737	675	472	575	508	25
Theravoor	632	712	666	478	549	505	24
Sooriyur	662	712	695	486	519	507	27
Perambur			637			470	25
Velur	687	737	712	506	560	533	25
Kathalur	620	776	734	448	595	568	23
Average	637	743	688	467	572	517	24.8
Tiruchirappalli district
(a) Manikandam
Poongudi	507	650	600	363	484	446	26
Tayanur	487	525	506	358	383	370	27
Senguruchi	495	525	510	358	377	368	28
Esanapatti			512			370	28
Navalurkuttupattu	627	682	658	458	510	488	26
Average	529	596	557	384	439	408	27
(b) Thiruverumbur
Navalpattu	487	675	554	350	500	405	27
Average	487	675	554	350	500	405	27
(c) Manapparai
Samudram	721	783	744	550	573	563	24
Sevalur	753	823	787	582	648	608	23
Pannapatty	488	813	661	364	634	506	23
Average	587	754	660	439	571	497	23.3
Over all Average	588	719	642	433	545	481	25.14

). The average blackgram seed yield of 719 kg ha⁻¹ was registered under IPT compared to farmers’ practices (642 kg ha⁻¹) in 235 demonstrations of 150 hectares (Table 6), which was 12.0% increase over the farmers’ practices. The increased grain yield with improved technologies was mainly due to line sowing, seed treatment with biocontrol agents and biofertilizer, use of foliar nutrients, proper irrigation scheduling, use of the optimum dose of NPK, and timely weed management. Other authors have also found similar results of higher seed yields in demonstration plots than of the existing practices in different crops [34,35,36,37,38,39].

3.3. Seed Quality Parameters

Quality of blackgram seed was ensured by testing with a notified seed testing laboratory in the Pudukkottai district of Tamil Nadu. The seeds were tested against the prescribed ‘Indian Minimum Seed Certification Standards’ (IMSCS). For the blackgram seeds produced through the farmer-participatory mode, the maximum genetic purity (99%), physical purity (98%), moisture content (9%), and seed germination (85%) were recorded (

Table 7. Seed quality parameters of blackgram seeds.

Seed Quality Parameters	FP *	IPT **
Genetic purity (%)	94	99
Physical purity (minimum) %	92	98
Germination (minimum)%	75	95
Hard seeds %	7	3
Seed viability %	82	98
Weed seed (No. kg−1)	12	5
Moisture content (%)	9.5	9

* Farmers’ practices; ** IPT—Improved Production Technology.

). The seed testing results received from the seed testing lab were printed on the seed tags attached to the seed bags [40]. Although recommended germination percent and physical purity are equally important, genetic purity is of utmost importance. Higher levels of physical impurities may impair crop performance by leading to lesser plant populations or by causing unwanted infestation by weeds. Likewise, recommended moisture percent helps in maintaining seed life and vigour during transportation or storage. Tetrazolium viability testing (TZ) demonstrated 98% viability by producing a cherry red colour stain in the seeds (Figure 2). The seed testing results confirmed that the blackgram seeds from farmers’ practices did not meet all IMSCS requirements, but the blackgram seeds produced through the IPT demonstration with farmer participation did meet the necessary criteria (Table 6).

3.4. Effectiveness of Irrigation

The results of the demonstration revealed that an average water productivity of 0.154 kg ha⁻¹ m⁻³ was observed under IPT in blackgram seed production compared to the conventional method (0.116 kg ha⁻¹ m⁻³). A higher water productivity of 0.174 kg ha⁻¹ m⁻³ was observed under IPT in blackgram in the Annavasal block than in the conventional method in the Manikandam and Thiruverambur blocks (0.085; 0.092 kg ha⁻¹ m⁻³) (

Table 8. Influence on IPT for seed production in blackgram on yield, water productivity, and economics, block-wise. in farmers’ fields.

S. No	Name of the Block and Village	Area (Acre)	Nos. of Demo	Qty. of Water Consumed (mm) (RF + IW)	Yield (kg ha−1)		Gross Income (Rs ha−1)		Cost of Cultivation (Rs ha−1)		Net Profit (Rs ha−1)		BCR		% of Increased Yield over FP	Water Productivity (kg ha−1 m−3)
					IPT	FP	IPT	FP	IPT	FP	IPT	FP	IPT	FP		IPT	FP
1	Annavasal	110	82	433	753	576	56,462	28,786	19,908	15,347	36,554	13,439	2.84	1.88	23.6	0.174	0.133
2	Viralimalai	160	86	406	687	517	51,560	25,848	19,817	15,193	31,742	10,655	2.60	1.70	24.9	0.169	0.127
3	Manikandam	33	21	479	557	408	41,767	20,416	19,943	15,022	21,824	5394	2.09	1.36	26.8	0.116	0.085
4	Thiruvarambur	32	14	443	554	407	41,550	20,338	20,014	15,214	21,536	5124	2.08	1.34	26.6	0.125	0.092
5	Manapparai	40	32	367	730	560	54,785	27,995	19,971	15,480	34,838	12,514	2.74	1.81	23.4	0.199	0.153
	Overall average	375	235	426	656	494	49,225	24677	19,931	15,251	29,299	9425	2.47	1.62	25.1	0.154	0.116

). It maintained an optimum plant population through line sowing, proper thinning, gap filling, and irrigating the crop at critical stages.

3.5. Economics

Costs involved in crop production, such as seeds, input costs (fertilizers, pesticides, etc.), and other agronomic management costs, including labour costs, were considered for cost economics for the IPT demonstrations and control. Actual seed costs have also been included according to the usage in both IPT and control. The economics of their different locations were worked out by using the current market price of inputs and blackgram seeds. The results revealed that, on average, in 235 different locations, the production of foundation seed of blackgram VBN 6 recorded a higher net income of Rs. 29,299 ha⁻¹ and a cost–benefit ratio of 2.47 under Improved Production Technology, compared to the farmers’ practices’ results of Rs. 9425 ha⁻¹ and 1.62 of net income and cost–benefit ratio, respectively (Table 8), and on average, an additional investment of Rs. 4679 ha⁻¹ was made under the IPT demonstrations.

Economic returns as a function of gain yield and Minimum Support Price (MPS) sale price varied throughout the different blocks of the Pudukkottai and Tiruchirappalli districts of Tamil Nadu state. In the Annavasal block of the Pudukkottai district, the maximum net return of Rs. 36,554 ha⁻¹ and a benefit–cost ratio of 2.84 were obtained due to the high blackgram seed yield and higher Minimum Support Price sale rates declared by the government of Tamil Nadu. The same block registered higher additional returns and effective gains of Rs. 27,676 ha⁻¹ and Rs. 23,115 ha⁻¹_, respectively, under demonstrations, which could be due to improved production technology, non-monetary factors, timely crop cultivation operations, and proper scientific monitoring. The lowest and highest incremental benefit–cost ratios (IBCRs) were 4.34 and 6.07 in the Annavasal and Manikandam blocks, respectively (

Table 9. Technological gap analysis, additional returns, effective gain, and incremental B:C ratio of demonstrations on blackgram seed production in farmers’ fields.

S. No	Name of the Block	Area (ha)	Nos. of Demo	Potnl. Yield (kg ha−1)	Yield (kg ha−1)		Gross Income (Rs ha −1)		EG (kg ha−1)	TG (kg ha−1)	TI (kg ha−1)	Addinl. Cost (Rs ha−1)	Addinl. Returns (Rs ha−1)	Effective Gain (Rs ha−1)	Incremental B:C Ratio
					IPT	FP	IPT	FP
1	Annavasal	44.0	82	890	753	576	56,462	28,786	177	137	15.41	4561	27,676	23,115	6.07
2	Viralimalai	64.0	86	890	687	517	51,560	25,848	171	203	22.76	4625	25,712	21,087	5.56
3	Manikandam	13.2	21	890	557	408	41,767	20,416	149	333	37.43	4921	21,351	16,430	4.34
4	Thiruvarambur	12.8	14	890	554	407	41,550	20,338	147	336	37.75	4800	21,212	16,412	4.42
5	Manapparai	16.0	32	890	730	560	54,785	27,995	171	160	17.93	4491	26,790	22,299	5.97
	Overall average	150	235	890	656	494	49,225	24,677	163	234	26.26	4679	24,548	19,869	5.25

IPT = Improved Production technology; FP = Farmers’ practices; EG = Extension gap; TG = Technology gap; TI = Technology index.

), depending on seed yield and MPS sale rates. The overall average IBCR was found to be 5.25. The results confirmed the findings of demonstrations on pulses in farmers’ fields by [33,41,42]. The village-wise benefit–cost ratios of these blocks, along with other details, are presented in Supplementary Table S1.

From the demonstrations, 985 farmers were made familiar with proper production technologies such as sowing in line, seed treatment with both bio fertilizers and bio inoculants, optimum application of fertilizers, proper irrigation during critical stages, especially flowering, pod formation, and development stages, foliar application of DAP and TNAU pulse wonder, and IPM practices for controlling pests and diseases. Quality seeds are readily available for farmers at planting time [43] with lower costs than certified seed [44]. Farmers gained knowledge and skills in seed selection and treatment [45,46], control of weed contamination and disease transmission (especially in vegetatively propagated seeds), timing of seed harvest, drying to acceptable moisture content, and proper seed storage [47].

Moreover, farmers were trained in seed registration procedures, roughing off-type plants, grading, collection of seed samples for germination tests, bagging, and labelling. These demonstrations increased soil fertility and built the relationship and confidence between farmers and agricultural scientists. Seed production is skill-oriented work which generates employment opportunities for rural youths, farm workers, farm women. A huge number of farm workers and farm women are involved in roguing operations, harvesting, and post-harvesting handling of seed produce, viz., seed processing, grading, treating, bagging, storage, transporting, and marketing. Thus, seed production programmes strengthen rural employment as unemployed rural youths will be engaged in seed production activities [30].

3.6. Yield Gap Analysis

The evaluation of the findings of this study (Table 9) states that a yield gap of 147 to 177 kg ha⁻¹ was found between the demonstrated technology and farmers’ practices, and on average, the yield gap was 163 kg ha⁻¹. The extension gap was highest (177 kg ha⁻¹) in the Annavasal block and lowest (147 kg ha⁻¹) in the Manikandam block. Such a gap might be attributed to the adoption of improved technology, especially high-yielding varieties like VBN 6, line sowing, seed treatments, foliar nutrition, weed management, and suitable (required) plant pest and disease management in the IPT demonstrations, which might have contributed to a higher grain yield than the control (farmers’ practices). This study further exhibited a wide technology gap in five different blocks. It was the lowest (137 kg ha⁻¹) in the Annavasal block of the Pudukkottai district and the highest (336 kg ha⁻¹) in the Thiruvarambur block of the Tiruchirappalli district. The average technology gap of all five blocks was 234 kg ha⁻¹. The difference in technology gap in the different blocks was due to favourable soil, better performance of blackgram VBN 6 with different interventions, and greater suitability of recommended technologies during the course of the study.

The technology index (TI) calculated for the IPT demonstrations indicated the gaps in technology. The results showed that the maximum TI (technology index) showed that there is a wider gap in the transfer of technologies (ToT) to farmers, and this may be due to inactive services of extension by agriculture departments. On the basis of five blocks in this blackgram seed production study, an average technology gap of 26.26% was recorded, which ranged from 15.41% in the Annavasal block to 37.37% in the Thiruvarembur block. Hence, it can be inferred that the awareness and adoption of improved varieties with recommended scientific production technologies have increased during the advancement of the study period [48,49,50]. These findings are consistent with the results of the study carried out by [51,52,53]. Moreover, optimizing resource utilization is crucial for pulse cultivation’s ecological integrity and financial sustainability, involving efficient management of water and fertilizers to minimize waste and environmental impacts [54]. In subsequent years, farmers in the study areas have practiced improved agronomic practices, including the growing of blackgram cultivar VBN 6 and early maturing varieties, resistance to mungbean yellow mosaic virus, and soil and water management activities [55].

4. Conclusions

It is concluded that front-line demonstrations were effective tools for increasing the productivity and quality of seed production of blackgram. The results revealed that the production of quality seed of blackgram through the adoption of improved production technologies significantly increased the seed yield by 25.14%, water productivity 32.8%, the yield attributing traits of the blackgram, and seed viability by 19.5% and resulted in additional net returns of Rs. 19,874 ha⁻¹ to the farmers compared to the farmers’ original practices. Before the demonstration, farmers used Urea, SSP, and MOP, and seed rates were higher than the recommended dose for general blackgram cultivation. However, through these demonstrations, farmers learned about and enriched their knowledge on the use of high-yielding MYMV-resistant blackgram varieties, the correct seed rate, line sowing, seed treatment with Imidacloprid, Pseudomonas, Rhizobium, and phosphobacteria, the optimum dose of Urea, SSP, and MOP, DAP/TNAU pulse wonder spray, and seed production procedures, viz., seed registration, rouging, and post-harvest technologies for pulses, and also understood the additional benefit of blackgram seed production compared to grain cultivation. Therefore, there is a need to disseminate these improved technologies among farmers with effective extension methods like training, field days, exposure visits, and demonstrations. These kinds of demonstrations created better inquisitiveness and motivation for those regional farmers who were not part of these demonstrations on IPT.

The main impact of the interventions of IPT for seed production in blackgram is that the farmers are enriched with technical knowledge, which changes their attitudes towards the adoption of proper production technologies. Most of the farmers expressed views that they had never adopted the measures for seed treatment and plant density, as well as those for the quantity of spray fluid for both growth regulators and pesticides. Now, they are well aware of the technologies and their impact on yield. Further, other agronomic management practices, such as timely weeding, application of water according to a crop’s water requirements, integrated pest and disease management, and nutrient management, also need to be given due care to enhance blackgram production. This will result in increased income as well as the livelihood of the farming community in the districts and ensure a quality seed production system.

Participatory seed production in association with farmers is the need of the day, where good quality seed production may be made available at the local level and cater to the needs of nearby villages. Successful seed production with farmers will be ensured only when seed-producer groups are formed. Presently, group approach will strengthen individual farmers, which in turn helps in fulfilling common demands. This system will also benefit the seed-producing agencies, not only in the timely distribution of seed but also in field visits, communicating with seed growers, and finally bringing the seed produce to the seed processing centres. Therefore, participatory seed production is a highly practical approach and needs to be promoted to facilitate the production and timely distribution of quality seeds of desired varieties at the village level.