64 The rapid growth in population increases urbanization and industrialization which results in scarcity of fresh water for irrigation. However, larger amounts of freshwater are diverted to domestic, commercial, and industrial sectors, which generate greater volumes of wastewater (Qadir et al. 2007a). In India, only 24% of wastewater generated by households and industry is treated before its use in agriculture or disposal to rivers (Minhas and Samra 2003). Wastewater treatment plants in most cities in developing countries are non-existent or function inadequately (Qadir et al. 2007b). Therefore, wastewater in partially treated, diluted or untreated form is diverted and used by urban and peri-urban farmers to grow a range of crops (Ensink et al. 2007). The untreated wastewater contains pathogens and toxic pollutants which will cause harm to the human health and environment. In such a condition, growing of fower crops with wastewater irrigation can be a good option to the urban and peri-urban farmers for improving their livelihood without entering the contaminants in the food chain. Due to the adequate availability, less energy Indian Journal of Agricultural Sciences 88 (4): 584–9, April 2018/Article https://doi.org/10.56093/ijas.v88i4.79120 Impact of wastewater irrigation on vegetative growth, fowering characteristics, keeping quality and productivity of tuberose (Polianthes tuberosa) D S GURJAR 1 , R KAUR 2 and K P SINGH 3 ICAR-Indian Agricultural Research Institute, New Delhi 110 012 Received: 05 November 2017; Accepted: 29 December 2017 ABSTRACT A feld experiment was conducted to assess the impact of wastewater irrigation on vegetative growth, fowering characteristics, keeping quality and productivity of tuberose (Polianthes tuberosa L. cv. Prajwal) at WTC farm of ICAR-Indian Agricultural Research Institute, New Delhi during three consecutive seasons of the year 2013-14, 2014- 15 and 2015-16. Seven treatments were taken as T-1: Wastewater irrigation at 0.6 irrigation depth (ID)/ cumulative pan evaporation (CPE), T-2: Wastewater irrigation at 0.8 ID/CPE, T-3: Wastewater irrigation at 1.0 ID/CPE, T-4: Wastewater irrigation at 1.2 ID/CPE, T-5: Wastewater irrigation at 1.4 ID/CPE, T-6: Conjunctive use of groundwater and wastewater irrigation at 1.0 ID/CPE in cyclic mode, T-7: Control (groundwater irrigation at 1.0 ID/CPE) in randomized block design with three replications. Results indicated that the vegetative growth parameters such as days to sprouting of bulb, days to spike emergence, number of leaves/clump, length and width were not much changed, whereas the signifcantly higher values of fowering parameters such as spike length, rachis length and number of forets/spike were observed under application of wastewater irrigations at 1.2 ID/CPE. Keeping quality parameters such as durability of spike and fower in feld and vase life of spike and fower were not signifcantly affected due to application of wastewater irrigations in tuberose. Signifcantly higher marketable cut spike and loose fower yield was observed where wastewater irrigations applied at 1.2 ID/CPE. It is concluded that wastewater irrigation is suitable for enhancing the productivity of tuberose without deteriorating the keeping quality of tuberose fowers. Key words: Conjunctive use, ID/CPE, Irrigation, Keeping quality, Tuberose, Wastewater 1 Scientist (e mail: dsgurjar79@gmail.com), 2 Principal Scientist (e mail: rk132.iari@gmail.com), Water Technology Centre, 3 Principal Scientist (e mail: kpsingh.dfr@gmail.com), Division of Floriculture and Landscaping. requirement and nutrient richness, wastewater can be a safe and economical alternate source of irrigation water for cultivation of tuberose in urban and peri-urban areas. Tuberose (Polianthes tuberosa L. cv. Prajwal) is one of the most important commercially grown fower crop in India. Its popularity is mainly due to the sweet fragrance as well as the long keeping quality of the fower spikes. The fower spikes of tuberose has high market price and usually blooms during summer season when there is meager supply of other fowers in the market. It is estimated that in India tuberose is commercially cultivated over 30000 ha area (Singh et al. 2010). The quantity as well as the quality of the fower spikes depends on a number of factors out of which inadequate water supply is the most important factor limiting tuberose productivity. A perusal of literature, however, shows that there is almost nil information available on application of wastewater irrigations in tuberose. Therefore, it is an urgent need to conduct a study for judging the suitability of wastewater irrigation for tuberose. Keeping in view, the present study was undertaken to assess the impact of wastewater irrigation on vegetative growth, fower productivity and keeping quality of tuberose. MATERIALS AND METHODS A feld experiment was conducted for three consecutive