Role of Fortified Organic Manures in Fertility Restoration of Coastal Problem Soil

The distinctive characteristic of coastal agroecosystems is soils that are dominated by salinity, sodicity, sandy texture, and nutrient deficiency. Poor yield realization is caused by high pH and salinity, which limit the availability of plant nutrients, particularly micronutrients. Coastal regions have a wealth of organic materials that can be fortified with nutrients to boost nutrient content and efficiency, which improves the efficacy of the process of restoring soil fertility. Pot and field experiments were conducted in coastal soil with the aim of evaluating the impact of fortified organic manures on physicochemical characteristics, nutrient availability, and crop yield. In an incubation experiment, coastal saline-sodic soil having an initial pH-8.88 and EC-2.16 dS m-1, the treatments including Control, ZnSO4 fortification @ 75%, 100%, and 125%, Fe SO4 fortification @75%, 100%, and 125%, and ZnSO4 + FeSO4 fortification @ 75%, 100%, and 125%, as main treatment and control, FYM, Coir pith, Casuarina needles and Green leaf manure as subplot treatment were replicated thrice in a Factorial Completely Randomized Design (FCRD). The experiment findings demonstrated that the application of FeSO4 + ZnSO4 enriched green leaf manure and coir pith greatly increased the availability of major and micronutrients in the soil while decreasing salinity and sodicity. A field experiment was conducted with the objective to find out the effect of organic manure fortified with micronutrients viz., ZnSO4 and FeSO4 on the growth and yield of rice in coastal saline soil. The treatments were T1–Recommended level NPK, T2 –NPK + ZnSO4 + FeSO4 @ 25 Kg ha-1 , T3 – NPK + Green manure fortified ZnSO4 + FeSO4 @ 75% RL, T4 – NPK + Green manure fortified ZnSO4 + FeSO4 @ 100 % RL, T5 – NPK + Green manure fortified ZnSO4 + FeSO4 @ 125% RL, T6 – NPK + Coir pith fortified ZnSO4 + FeSO4 @ 75% RL, T7 – NPK + Coir pith fortified ZnSO4 + FeSO4 @ 100% RL and T8 – NPK + Coir pith fortified ZnSO4 + FeSO4 @ 125% RL. The findings demonstrated that rice growth and yield characteristics were greatly improved by micronutrient-fortified composted green leaf manure as compared to other treatments. In the coastal region, about 50% of the soil is sandy with poor texture, low CEC, organic matter, and low levels of micronutrients. A pot experiment was conducted utilising coastal sandy soil having low N, P, K, Zn, and B status with the aim of evaluating the effects of various organics combined with micronutrients on the growth, yield, and nutrient uptake of groundnut in coastal soil.The treatment schedule were T1-Absolute control, T2- 100% recommended NPK, T3-T2+ ZnSO4 25 kg ha-1+ Borax @ 10 kg ha-1. T4- T2+Zn+B+ Composted coirpith @ 10 t ha-1, T5 - T2 + Zn + B + Humic acid @ 20 kg ha-1 and T6- T2 + Zn + B + Composted coirpith and Humic acid. The results revealed that the combined application of Zn + B along with Composted Coir Pith and Humic acid significantly increased the growth and yield of the groundnut besides increasing the soil available nutrients.