~ 3084 ~ Journal of Pharmacognosy and Phytochemistry 2019; 8(3): 3084-3088 E-ISSN: 2278-4136 P-ISSN: 2349-8234 JPP 2019; 8(3): 3084-3088 Received: 28-03-2019 Accepted: 30-04-2019 T Kanchana Post Graduate Student, Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India N Sakthivel Associate Professor (Agronomy), Department ofAgronomy, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India N Thavaprakaash Associate Professor (Agronomy), Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India J Balamurugan Assistant Professor (Soil Science and Agricultural Chemistry), Department of Soil Science and Agricultural Chemistry, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India Correspondence T Kanchana Post Graduate Student, Department of Agronomy, Tamil Nadu Agricultural University, Coimbatore, Tamil Nadu, India Performance of compact cotton ( Gossypium hirsutum L.) genotypes to varied nutrient levels under high density planting system in winter irrigated condition T Kanchana, N Sakthivel, N Thavaprakaash and J Balamurugan Abstract A field study was conducted during winter season (August-January) of 2018-19 in Tamil Nadu Agricultural University, Coimbatore to study the influence of compact cotton (Gossypium hirsutum L.) genotypes to varied nutrient levels under high density planting system. There were twelve treatment combinations, containing three variety/genotype in main plot (M1-CO 15, M2- TCH 1819 and M3- TCH 1822) and four nutrient levels in sub plots (S1- 100% Recommended dose of fertilizer (RDF), S2- 125%RDF, S3- 150%RDF and S4-STCR based recommendation and the experiment was replicated thrice in a split plot design. The results revealed that growth of cotton crop like plant height, leaf area index and drymatter production was higher in CO 15 variety than other genotypes. Genotype TCH 1822 recorded higher yield (2335 kgha -1 ) with higher boll weight (4.72 gboll -1 ) than others. Application of 150% RDF (100:50:50 kg NPKha -1 ) recorded higher growth parameters while application of 125% RDF (100:50:50 kg NPKha -1 ) recorded higher yield (2324 kgha -1 ) with more number of bollsplant -1 (13.78) and higher boll weight (4.53 gboll -1 ) over other levels. Keywords: Cotton, high density planting system, variety/genotype, nutrient levels, growth, yield Introduction Cotton (Gossypium spp.), the white gold is the widely used natural fibre and leading fibre crop around the world so called as ‘King of fibres’. It is grown in more than 100 countries under diverse agro-climatic conditions around the world (Anon., 2012) [3] . The cotton farming systems vary widely between geographical areas. In countries such as USA, Australia and Brazil, cotton is grown on larger, modernized farms using more mechanized technology. In India, it is in small-scale with labour intensive production like hand weeding and picking. The high density planting system is now being conceived as an alternate production system having a potential for improving the productivity and profitability, increasing input use efficiency, reducing input costs and minimizing the risks associated with the current cotton production system in India (Venougopalan et al., 2013) [20] . The availability of compact genotypes, altering of crop geometry, application of growth regulators and application of fertilizers on need based will bring the high density cotton under mechanized cultivation in India. To mechanize the cotton cultivation since it is a labour intensive and to increase the profitability, compact cotton genotypes provide a great scope. Compact genotypes are ideally suited for machine pickings and high density planting because of their short stature, lesser vegetative growth, fewer and shorter fruiting branches, short inter branch and inter boll distance and synchronous maturity(Coffey and Davis, 1981) [6] . Due to their earliness it can be harvested in two or three pickings (Patil et al., 2007) [12] . Mostly all plants require the same mineral elements; however, the quantity, rate and timing of uptake vary with crop, variety, climate and soil characteristics. For every 100 kg of seed cotton produced, the crop depleted the soil by 6-7 kg of N, 1.9-2.5 kg P, 6-8 kg of K (Singh and Blaise, 2000) [15] . It is necessary to find whether the demand for nutrients is greater under high density planting system (HDPS) since the plant population is higher. So, to sustain the cotton productivity with economic and environmental safety, there is a need to optimize the nutrient requirement for Gossypium hirsutum of compact variety/genotypes at a spacing of 100 x 10 cm accommodating 1,00,000 plantsha -1 . Hence, the present study was formulated to study the nutrients influence on varieties/genotypes suits for HDPS.