Abstract

Field experiment was conducted at Lower Bhavani Project (LBP) area to study the effect of application of flyash in combination with fertilizer, organic manures and biofertiliser (Azospirillum) on soil properties and yield of rice. The flyash contains a wide range of nutrients (P, K, Fe, B, Si, Ca, Mg and S) and traces of heavy metals. The results of the experiment revealed that application of flyash @ 20 and 40 t ha significantly increased the grain yield of rice crop to the tune of 5.6 and 12.5 t ha', respectively. Application of NPK fertilisers as per STCR technology through fertilisers, fertilizer + compost and fertilizer + compost +Azospirillum recorded an yield increase of 3.12, 3.53 and 3.56 t ha' respectively over the treatments without any fertilizer addition. The highest yield of 7.26 t ha' was recorded in the treatment which received flyash @ 40 t ha' along with fertilizer; compost and fertilizer. The significant increase in the nutrient uptake of rice indicated that flyash could serve as source of plant nutrients. The results of the post harvest soil analysis indicated that application NPK ferilisers significantly increased the available NPK status of the soil, while application of flyash significantly increased the available P, K, Ca, Mg, S, Si and B content of the soil. The effect of flyash was more pronounced when applied along with fertilisers and organic manures.

Keywords: Flyash, STCR technology, fertiliers, compost, biofertiliser, nutrient uptake, grain yield, available nutrients.