~ 722 ~ Journal of Pharmacognosy and Phytochemistry 2019; SP2: 722-725 E-ISSN: 2278-4136 P-ISSN: 2349-8234 JPP 2019; SP2: 722-725 Anuratha A Assistant Professor (SS&AC), ICAR Krishi Vigyan Kendra, Tamil Nadu Agricultural University, Needamangalam, Thiruvarur, Tamil Nadu, India R Ravi Assistant Professor (Forestry), Forestry College and Research Institute, TNAU, Mettupalayam, Tamil Nadu, India Selvi J Assistant Professor, (FSN), Community College and Research Institute, TNAU, Madurai, Tamil Nadu, India Correspondence Anuratha A Assistant Professor (SS&AC), ICAR Krishi Vigyan Kendra, Tamil Nadu Agricultural University, Needamangalam, Thiruvarur, Tamil Nadu, India Impact of cluster frontline demonstration on black gram in Nagapattinam district of Tamil Nadu Anuratha A, R Ravi and Selvi J Abstract The present study was carried out at Krishi Vigyan Kendra, Nagapattinam district of Tamil Nadu to know the yield gap between improved package and farmers’ practice under Front Line Demonstration. Black gram (Vigna mungo L.) is one of the most important pulse crop cultivated in Nagapattinam district of Tamil Nadu. It is having lower yield in farmer’s field due to multiple constraints. One of the major constraints of its lower productivity was non-adoption of improved technologies. Front line demonstrations on Improved Crop Management practices were conducted at 59 framer’s fields of Nagapattinam district during Kharif season from 2014-15 to 2016-17. The improved technologies recorded a mean yield of 7.09 q ha -1 which was 30.2 per cent higher than the yield obtained with farmers practice (5.79 q ha -1 ), besides having higher mean net income of Rs.17107 ha -1 with a B: C ratio of 1.94 when compared to farmers practice (Rs. 10633 ha -1 and 1.65). The average technological gap, extension gap and technological index noticed were 1.81 q ha -1 , 1.63 q ha -1 and 20.32 per cent respectively. The higher average grain yield was recorded in demonstration plots over the years compared to local check due to increased knowledge and adoption of full package of practices. Keywords: Black gram, Front line demonstrations (FLD), productivity, farmer’s field, net returns. Introduction Pulses have great importance in Indian agriculture as they have rich source of protein (17 to 25 per cent) as compared to that of cereals (6 to 10 per cent), their ability to fix atmospheric nitrogen and improve the soil fertility. Among pulses, black gram is one of the most important crop. Protein malnutrition is prevalent among men, women and children in India. Pulses contribute 11 per cent of the total intake of proteins in India (Reddy, 2010) [7] . In India, frequency of pulses consumption is much higher than any other source of protein, which indicates the importance of pulses in their daily food habits. Keeping the cheapest source of protein, it is important to increase pulses production to provide a balanced diet among the socially and economically backward classes. Pulses are water saving crops and more than 92 per cent of the area under pulses is rainfed. About 23 million tons of pulses are need to be imported every year to meet the domestic demand. The yield of pulses is less than the global average. Adoption levels for several components of the improved technology of the crop were low emphasizing the need for better dissemination. Several biotic, abiotic and socio-economic constraints inhibit exploitation of the yield potential of black gram and these are needed to be addressed. Crop growth and yield are limited through poor plant nutrition and uncertain water availability during the growth cycle. Inappropriate management may further reduce the fertility of soil (Rabbinge, 1995) [5] . The major constrains or lower yield of black gram is mainly attributed to their cultivation on poor soils with inadequate and imbalanced nutrition, use of local varieties, use of disease susceptible varieties, lack of seed treatment, lack of Integrated Weed Management (IWM) and lack of Integrated Pest Management (IPM) (Shetty et al., 2013) [9] . Front line demonstration (FLD) is one of the most powerful tools of extension because farmers, in general, are driven by the perception that “Seeing is believing”. The main objective of front line demonstrations is to demonstrate newly released crop production and protection technologies and its management practices in the farmer’s field. During demonstration in the farmer’s field, scientists are required to study the factors contributing higher crop production, field production constraints and there by convince the farmer to adopt the technology for higher yield. Here in front line demonstration farmer’s participatory approach is very useful method of owning and continuous interacting with scientists and getting the useful tips for getting higher yield in farmers own field which otherwise get lower yields (Bhargau et al., 2017) [1] and (Thakur et al., 2016) [11] . Keeping this in view Frontline demonstrations on black gram were conducted to demonstrate the production potentials and economic benefits of latest improved technologies