Influence of Organic Amendments on Soil Properties, Microflora and Plant Growth

The demand for agricultural products is growing daily, thus exerting an unseen pressure on the land due to the absence of resting and fallow periods. The continuous use of land requires better soil management strategy in order to improve soil physical, chemical and biological status. For instance, plant growth can be improved by the application of organic soil amendments. This chapter focuses on the use of different types of organic amendments and their role in improving the soil quality, plant growth and microflora in soil. Biofertilizer increases nitrogen content in the soil up to 40–250 kg N2/hectare/year and 50–80 kg N2/hectare/year following the respective inoculation of Rhizobium and Azotobacter. Application of pearl millet green manure increases the soil bulk density by 13.3%. Legume green manure increased the average yield of rice grain by 1.7 Mg/hectare. Soil pathogens are reduced when plant waste and animal waste are applied in compost form. Moreover, compost prepared from animal manure possesses highest humus content of 11.8%, C:N ratio 13.5, and humic acid fraction 2.84. Bamboo biochar increases the activities of enzymes such as beta-glucosidase alkaline phosphatase and urease, while rice hull biochar increases the activity of ascorbate peroxidase and glutathione reductase enzyme. Biogas slurry and spent mushroom compost increases the nitrogen content by 35.98% and 2.17%, respectively. Kelp weed acts as biostimulant while biogas slurry acts as bactericide and fungicide. Mulching helps in maintaining the moisture of the soil.