Deciphering the Amendment-Induced Secretion of Ligninolytic Enzymes by Pleurotus pulmonarius

Pleurotus pulmonarius belonging to the white-rot fungal basidiomycetes group secretes extracellular ligninolytic enzymes for the degradation of agroresidues. The present study was carried out to evaluate the efficacy of different agro-residues for the enhanced production of ligninolytic enzymes and to authenticate their ability by protein analysis. The morphological and molecular sequences of white-rot fungi were characterised. Besides, the efficacy of organic and inorganic amendments in the secretion of ligninolytic enzymes by P. pulmonarius was characterised using SDS-PAGE and native PAGE analysis. The characterised strain of P. pulmonarius secreted enhanced laccase enzyme levels in the liquid medium through supplementation with organic and inorganic amendments. Wheat bran and groundnut cake each @5% enhanced secretions of Laccase, LiP and MnP. Copper sulphate at 150 μM enhanced the laccase enzyme and at 100 μM enhanced the LiP enzyme level by P. pulmonarius. Similarly, supplementation with manganese sulphate at 150 μM enhanced laccase, LiP and MnP enzyme levels compared to control. SDS-PAGE results showed protein banding patterns in the range of 50–85 kDa for the Lac enzyme in samples drawn from wheat bran and groundnut cake-supplemented substrates. Native PAGE results of laccase enzymes also showed that wheat bran (5%) + groundnut cake (5%) + CuSO4 (150 M) + MnSO4 (150 M) induced four laccase isozymes. Supplementing organic and inorganic amendments to the substrates would enhance the secretion of laccase enzyme that would aid in better breakdown of lignin.

Interactive Effect of Organic and Inorganic Amendments along with Plant Growth Promoting Rhizobacteria on Ameliorating Salinity Stress in Maize

Saline soil is one of the common environmental issues that negatively affects the soil quality of agricultural lands. It reduces the plant growth and productivity worldwide. Soil Salinity and sodicity affecting land about 1128 million hectares globally determined by recent researches. The most important salt-sensitive cereal crops in the world are Maize (Zea mays L.) For food security, its need of hour to securing attainable production of maize crop in the salt affected soils. To reduce negative impacts of saline soil on plant growth, sustainable approaches such as organic amendments like press mud and inorganic amendments like silicon can be applied. For increasing crop productivity, plant growth promoting rhizobacteria (PGPR) which are salt-tolerant in saline agriculture can also be applied. In this book chapter interactive effect of different organic and inorganic amendments and plant growth-promoting rhizobacteria to reduce salinity stress on maize has been discussed.

Quantifying the effects of co-composting organic biomass mixtures with inorganic amendments to obtain value-added bio-products

Co-digestion of organic biomass mixed with inorganic amendments could have an impact on composting dynamics. Various studies highlighted fertilizers’ role as an additive to lesser the nitrogen loss, while some studies focused on the addition of fertilizers to enhance the efficiency. The changes in carbon, nitrogen components, and humic substances during the organic-inorganic co-compost process were seldom studied. Clarifying these changes might help improve the production process and compost nutrients contents. Thus, this study’s purpose is to investigate the effects of inorganic amendments on compost characteristics, compost temperature, biochemical methane production (BMP), and nutritional contents. The inorganic phosphorous (P), sulfur (S), and sulfur solubilizing agent (SSA) were added to Farmyard manure (FYM) mixed with biodegradable waste (BW), including wheat straw, corn stalks, and green lawn waste. The P and S amended treatments were carried out into two sets, with and without SSA. The mixed feedstocks were added in the insulated RBC composting pit (15 x 15 x 10 feet). The compost material’s moisture content was maintained 50–65% during the entire composting process for optimum waste digestion i.e., the moisture content (MC) of FYM was 82.7% and for BW ranged 8.8–10.2%, while the C/N ratio was found 10.5 for FYM, 74.5 for wheat straw, 83.5 for corn stalks, and 84.8 for lawn waste. At the condition of compost maturity, the inorganic amendments have no significant effect on composted material’s moisture content. The maximum organic matter of 69.7% and C/N ratio of 44.6 was measured in T1. On the 6th day of composting, the temperature reached to thermophilic range (>45 oC) in all the treatments due to aeration of compost increased microbial activities and waste decomposition rate and decreased gradually to mesophilic range (35–45 oC) because the supply of high-energy compounds becomes exhausted. The highest temperature was reached in T4 (58 oC) and lowest in CT (47 oC). The significantly maximum methane of 8.95 m3 and biogas burning was 818 minutes in CT, followed by T1 and T4. The results of this study revealed that P enriched compost is a feasible and sustainable way to overcome P deficiency in the soil as well as in plants and best way to use low-grade P and organic waste material.