Irrigation and nitrogen management in potato (Solanum tuberosum) and their residual effects on succeeding maize (Zea mays)

Field experiment was conducted in two consecutive rabi and summer seasons (OctoberJuly) of 2007-08 and 2008-09 at New Delhi to study the effect of irrigation and nitrogen management on productivity of potato (Solanum tuberosum L.) and their residual effect on succeeding maize (Zea mays L.). The experiment was laid out in split plot design with two irrigation methods (conventional furrow irrigation and alternate furrow irrigation) and three irri- gation regimes (60, 80 and 100 mm CPE) in the main plots and four nitrogen levels (90 kg N through urea + 30 kg N/ha through FYM, 120 kg N/ha through urea, 120 kg N through urea + 30 kg N/ha through FYM and 150 kg N/ hathrough urea) in sub-plots with three replications. Results indicated that significantly higher number of shoots/ hill, plant height, fresh and dry weight of haulms, fresh and dry weight of tubers/hill, yield of different grade tubers and total tuber and biological yields were obtained with conventional furrow irrigation as compared with alternate furrow irrigation in rotation. Among the irrigation regimes, irrigation at 60 mm CPE recorded significantly the high- est growth characters, yield attributes and total tuber and biological yields over irrigation at 80 and 100 mm CPE. Effects of N management on growth, yield components and yield was maximum with application of 120 kg N (urea) + 30 kg N/ha through (FYM), which was at par with 150 kg N/ha through urea. Residual effect of irrigation methods and regimes applied to potato on grain, stover and biological yields of maize was found to be non-signifi- cant. Significant residual effect of N management treatments applied to potato was noticed on maize. Residual ef- fect of 120 kg N (urea) + 30 kg N/ha through (FYM) applied to potato recorded the highest grain, stover and bio- logical yields and protein content of maize and it was at par with 150 kg N/ha through urea applied to potato.