Abstract

                                A field experiment was conducted during Kharif 2010 with a view to find out the effect of different integrated nutrient management practices on soil quality parameters, growth, yields and yield attributes and nutrient uptake by maize (PEHM-5) under managed temporary excess soil moisture stress at knee high stage in mollisol. Results showed an improvement in soil quality parameters in plots supplied with organic sources either individually or combination of all with 100% NPK fertilizers to that grown with inorganics alone or no fertilizers. Bulk density was lowest under combined application of vermicompost, zinc, PSB and Azospirillum with 100% NPK but applied ZnSO4 increased bulk density to a maximum of 1.38 Mg m-3 . Inoculation of biofertilizers along with vermicompost enhanced organic carbon by 0.02 - 0.14 per cent over other treatments. Availability of N, P, K and Zn was significantly influenced by applied organic sources with chemical fertilizers. Treatments received 100% NPK along with zinc, Azospirillum, PSB and vermicompost significantly recorded higher values of 187.32, 31.96, 178.35 and 2.71 kg ha -1 available N, P, K and Zn, respectively, but individual application of Azospirillum, PSB and zinc responded to least availability of zinc, N and P, respectively. Higher total uptake of N, P, K and Zn was recorded with combined application of organic and inorganic inputs with 100% NPK followed by 100% NPK+ vermicompost. Nutrient management practices had significant effect on growth, yields and yield attributing parameters; however nodes with brace roots and ASI were not significantly affected. Different organic and inorganic combinations produced 144-917 kg ha -1 more grain yield over 100% NPK whereas reduced by 1237-2154 kg ha -1 to the treatment subjected to no submergence. Inclusion of Azospirillum and PSB with 100% NPK gave statistically on par grain yields. Maize plants grown with vermicompost, 125% NPK and combination of all inputs showed in general, lower net photosynthetic rate, transpiration rate and leaf temperature, respectively, while higher leaf diffusive resistance to that of normal condition. Integrated use of biofertilizers and vermicompost with 100% NPK was found to be the best for maize production under excess soil moisture stress.

Key words : Temporary water logging, maize, nutrient management, biofertilizers, physiological parameters, mollisol