Evaluating the nitrification inhibition potential of selected botanicals and their non-target effects

Nitrification inhibitors (NI) are aimed at improving N-fertilizer use efficiency in cropping systems. This study to assess the nitrification inhibition potential and non-target effects of dry leaf powders (botanicals) ten plant species [neem (Azadirachta indica), lantana (Lantana camara), karanda (Pongamia pinnata), Brachiaria humidicola, cinnamon (Cinnamomum verum), clove (Syzygium aromaticum), wild-sunflower (Tithonia diversifolia), mee (‎Madhuca longifolia), nutmeg (Myristica fragrans) pepper (Piper nigram)]. The effect botanicals on growth three ammonia oxidizing bacteria isolates (M4, M5 M7) NO3- formation soil were tested laboratory experiments. In a pot-experiment, applied with urea their vegetative-growth tomato capsicum. fungi, seed germination assessed separately. Dicyandiamide (DCD) was used as positive control all Only M7 significantly suppressed by except neem, pepper. highest shoot-biomass obtained when Nitrate leaching from pots reduced (p<0.05) added for basal-dressing. abundance culturable fungi not affected while consistently only. From nutmeg, lantana, cinnamon, mee, identified materials better suppress minimum effects.