1 Rex Immanuel, R. et al. Plant Archives Vol. 21, Supplement 1, 2021 pp. 2041-2045 e-ISSN:2581-6063 (online), ISSN:0972-5210 Plant Archives Journal homepage: http://www.plantarchives.org doi link : https://doi.org/10.51470/PLANTARCHIVES.2021.v21.S1.334 NUTRIENT UPTAKE AND USE EFFICIENCY OF MAIZE (ZEA MAYS L.) AS INFLUENCED BY MICROBIAL SEED INOCULATION, NPK FERTILIZATION AND PANCHAGAVYA FOLIAR APPLICATION Rex Immanuel, R., G.B. Sudhagar RAO*, M. Saravana Perumal, K. Arivukkarasu and V. Mullaivendhan Department of Agronomy, Faculty of Agriculture, Annamalai University, Annamalainagar – 608002, Tamil Nadu, India. *Corresponding author ABSTRACT The nutrient use efficiency of maize (Zea mays L.) due to NPK fertilization alone is low, while, an integrated use of nutrients enhances the uptake and efficiencies of applied nutrients. A field study was carried out to test the effect of fertilizer NPK, microbial seed treatment and panchagavya on grain yield, nutrient uptake and use efficiencies of relay cropped maize during the summer season of 2018 in Annamalai University Experimental Farm, Annamalainagar, Tamil Nadu. Thirteen treatments comprised of 100, 75 and 50% of RDF in combination with and without seed treatment of microbial consortia and 3% panchagavya foliar spray at knee high and pre-tasseling stages. The maximum grain yield, NPK uptake, physiological efficiency, internal efficiency and unit area efficiency were registered with integrated application of 100% RDF (250:75:75 kg N, P 2 O 5 and K 2 O/ha) along with seed treatment with microbial consortium and foliar application of panchagavya at knee high and pre-tasseling stages. However, grain yield and NPK uptake were statistically on par with integrated application of 75% RDF (188: 56: 56 N, P 2 O 5 and K 2 O kg/ha), seed treatment with microbial consortium (20 ml/kg) and 3% panchagavya foliar application at knee high and pre-tasseling stages. The agronomic efficiency, apparent nutrient recovery, value cost ratio was high in integrated application of 75% RDF, seed treatment with microbial consortium and 3% panchagavya foliar application at knee high and pre-tasseling stages and was considered as an effective agro-technology. Keywords : Coastal agroecosystem, biofertilizers, foliar fertilization, nutrient uptake, relay cropping, rice based cropping system Introduction Rice (Oryza sativa L.) and maize (Zey mays L.) crops are grown either as a monocropping or in sequential cropping in tropical and sub-tropical/irrigated regions of India. In the irrigated areas, rice-maize relay/ fallow cropping under zero till condition is emerged as one of the most important cropping system. Rice-maize cropping systems are followed mostly in the northeast (Bihar and West Bengal) and south (Andhra Pradesh, Karnataka and Tamil Nadu) regions of India with an area of more than 0.5 mha (Ahirwar and Khan, 2019). This system meets the twin requirements such as food stuff of a fast growing human population and feed demand of livestock. Monsoon failures and decline in availability of irrigation water replaced the rice-rice cropping system in to rice–maize cropping system. Rice (Oryza sativa L.)-maize (Zea mays L.) cropping systems are prevalent in mostly all agro-climatic regions of southern India (Mahto et al. 2018; Rex Immanuel et al. 2019a). Yield potential of rice and maize, as estimated by Oryza, 2000 and hybrid maize models, reaches up to 15 and 22 t ha -1 , respectively (Ahirwar and Khan, 2019). In recent years, popularity of maize as relay crop is increased (Leela Rani and Yakadri, 2017; Rex Immanuel et al., 2020). Intensive cropping systems with high yielding maize hybrids will lead to the very fast depletion of plant nutrients from rhizosphere because of the greater nutrient uptake and removal by maize than other cereals. Hence, monitoring the nutrient uptake and its use efficiency by maize crop in rice- maize cropping system is paramount important. Mineral fertilizers are used to provide soil nutrients in order to maintain optimum soil fertility conditions, growth of the plants and quality yield (Sudhagar Rao et al., 2017). In rice growing coastal regions of Tamilnadu, there is an acute shortage of irrigation water for raising nursery and delayed transplanting, which caused reduced crop yield as well as failure of second crop. As a result, wet spot seeded rice in puddled soils followed by relay cropped maize can be a substitute for sustaining the small and marginal farmer’s livelihood (Rex Immanuel et al., 2018). Maize crop has better yield response to inorganic fertilizers however heavy doses of fertilizer application lead to nutrient losses through leaching, volatilization and finally involved in to the deterioration of associated ecosystems (Kalhapure et al., 2013). The degraded nature of the soils especially in coastal agroecosystems further affects the crop production and hence these lands are diverted to other land uses (Rex Immanuel and Ganapathy, 2019b; Rex Immanuel and Ganapathy, 2019c).