Kahlon, M.S.Goyal, Ruchi2021-01-142021-01-142020Goyal, Ruchi (2020). Effect of irrigation in combination with farmyard manure, biochar and nitrogen levels on growth and water productivity of spring maize (Unpublished M.Sc. thesis), Punjab Agricultural University, Ludhiana, Punjab, Indiahttps://krishikosh.egranth.ac.in/handle/1/5810160077The use of biochar and other organic amendments not only reduce the dosage of fertilizers but also helps in improving soil physical health, crop growth and water productivity. Thus, a field experiment was conducted on spring maize in split plot design with three replications having six organic and inorganic treatment combinations i.e. BN1 (biochar @ 7.5 t ha-1 + N @ 75 kg ha-1), BN2 (biochar @ 7.5 t ha-1 + N @ 150 kg ha-1), FN1 (farmyard manure @ 20 t ha-1 + N @ 75 kg ha-1), FN2 (farmyard manure @ 20 t ha-1 + N @ 150 kg ha-1), N1 ( N @ 75 kg ha-1) and N2 (N @ 150 kg ha-1) in main plots and two irrigation regimes i.e. Irrigation Water/ Cummulative Pan Evaporation I1 (IW/CPE ratio 0.6) and I2 (IW/CPE ratio 0.9) in sub plots. Significant differences due to amendments were reported for soil moisture retention, mean weight diameter and saturated hydraulic conductivity. Maximum soil moisture retention at 0.3 bar was observed in biochar treatment BN1 i.e. 30.0%, while the minimum was recorded in N2 i.e. 25.5%.Among plant parameters, maximum plant height, SPAD value, crop biomass, thousand grain weight, grain yield and water productivity were recorded in BN2 which were 12.3 %, 20.4 %, 25.2 %, 11.3%, 28.5 % and 41.3 % higher over control i.e. N2 treatment. Irrigation regime I2 significantly increased the relative leaf water content, crop biomass, thousand grain weight, harvest index and grain yield by 1.2 %, 2.0 %, 3.9 %, 5.2 % and 11.8 % over I1 regime. Hence, it is concluded that for improving soil physical health, crop growth and water productivity the biochar treatment i.e. BN2 along with IW/CPE ratio 0.9 is a suitable practice for northwest India, however, under limited resources BN1 along with IW/CPE ratio 0.6 may be suitable option for achieving optimum productivity.EnglishThesis