Effect of Spent Mushroom Compost of Pleurotus pulmonarius on Growth Performance of Four Nigerian Vegetables

Effects of an efficient straw decomposition system mediated by Stropharia rugosoannulata on soil properties and microbial communities in forestland

Cultivation of Stropharia rugosoannulata with straw in forestland is effective for straw biodegradation and can prevent the waste of straw resources and environmental pollution and generate economic benefits. However, there is a lack of systematic evaluation of spent mushroom substrate (SMS) input into forestland, such as soil properties and microbial succession. In this experiment, 0 (CK), 10 (SA), 20 (SB), 30 (SC), 40 (SD), and 50 (SE) kg/m2 straw were used to cultivate S. rugosoannulata, and two soil layers (0-10 cm, 10-20 cm) of the cultivated forestland were analyzed. The results indicated that SMS significantly promoted nutrient accumulation in forestland. The bacterial alpha diversity in the SC treatment group was greater than that in the control and gradually decreased to the control level with interannual changes, while the trend of fungal alpha diversity was opposite to that of bacterial alpha diversity. Furthermore, the SC treatment group positively affected soil nitrogen metabolism-related microorganisms for two consecutive years and significantly promoted tree growth. Habitat niche breadth and null model analysis revealed that bacterial communities were more sensitive than fungal communities after SMS input. Linear mixed model (LMM) analysis revealed that SMS supplementation significantly positively affected bacteria (Gammaproteobacteria and Bacteroidota) and significantly negatively affected fungi (Coniochaetales). The constructed fungal-bacterial co-occurrence networks exhibited modularity, and the five types of bacteria were significantly correlated with soil organic matter (SOM), soil organic carbon (SOC), available potassium (AK), available phosphorus (AAP) and available nitrogen (AN) levels. The structural equation model (SEM) showed that bacterial diversity responded more to changes in soil nutrients than did fungal diversity. Overall, 30 kg/m2 of straw decomposition and 2 years of continuous cultivation were beneficial to soil health. This study provides new insights into the rational decomposition of straw and maintenance of forestland ecological balance by S. rugosoannulata.

Macrofungi Cultivation in Shady Forest Areas Significantly Increases Microbiome Diversity, Abundance and Functional Capacity in Soil Furrows

Cultivating macrofungi is an important management measure to develop economy in shady forest areas; however, its effect on soil ecology, especially microbial abundance and structure, remains insufficiently studied. Herein, in a subtropical forestland, soil chemical and enzyme analyses, metagenomic sequencing and quantitative real-time PCR were employed to evaluate the impact of Stropharia rugosoannulata cultivation on soil microbiomes in three niches: soil below fungal beds, soil from furrows, and control forest soil with no influence from mushroom cultivation. Nutrients were accumulated in the soil below fungal beds with a significant increase (p < 0.05) in SOC, total C, total N, available P, and the activities of glucosidase and cellobiosidase. Non-metric multidimensional scaling and PERMANOVA results indicated that the structure of the microbiomes had been significantly (p < 0.05) shaped among the different niches. Soil furrows were microbial hotspots characterized by the higher microbial diversity and richness. Moreover, the increased microbiome abundance (assessed through qPCR) and the high number of significant stimulated functional types (based on MetaCyc genome database) indicated an enhanced functional capacity in furrows. Together, these results provide a comprehensive understanding of the microbial assemblies and the differently influenced soil properties in mushroom cultivation areas.

Short Rotation Intensive Culture of Willow, Spent Mushroom Substrate and Ramial Chipped Wood for Bioremediation of a Contaminated Site Used for Land Farming Activities of a Former Petrochemical Plant

The aim of this study was to investigate the bioremediation impacts of willows grown in short rotation intensive culture (SRIC) and supplemented or not with spent mushroom substrate (SMS) and ramial chipped wood (RCW). Results did not show that SMS significantly improved either biomass production or phytoremediation efficiency. After the three growing seasons, RCW-amended S. miyabeana accumulated significantly more Zn in the shoots, and greater increases of some PAHs were found in the soil of RCW-amended plots than in the soil of the two other ground cover treatments' plots. Significantly higher Cd concentrations were found in the shoots of cultivar 'SX61'. The results suggest that 'SX61' have reduced the natural attenuation of C10-C50 that occurred in the unvegetated control plots. The presence of willows also tended to increase the total soil concentrations of PCBs. Furthermore, we found that many contaminant concentrations were subject to seasonal oscillations, showing average increases throughout the whole experimental site after a growing period, while showing significantly different variations, such as lesser increases or even decreases, after a dormant period. These observations suggest that contaminants may have leached or degraded faster in untreated conditions, and conversely to have mobilized towards trees through water flow driven by plant transpiration during growing seasons.

Amelioration of Composts for Greenhouse Vegetable Plants Using Pasteurised Agaricus Mushroom Substrate

When using food and green waste composts as peat-free plant growing media, there is a challenge that nutrient immobilisation and high pH and salts content limit plant growth. The present study explored the use of spent mushroom compost (SMC) of Agaricus subrufescens in a sustainable plant growing system where only vermicompost from digested food waste and composted green wastes were used, even for the seedling stage. However, negative effects of high compost inclusion were offset by adding SMC. Significantly higher plant yield was obtained in several of the SMC amended treatments in four out of five lettuce experiments and in one tomato experiment. In addition, an experiment with cucumbers showed that nutrients were not available to the plant when the mushroom mycelium was actively growing, but became available if the mushroom mycelium had been inactivated first by pasteurisation. A significant effect from SMC was not observed under full fertigation. This study demonstrated that the addition of pasteurised Agaricus mycelium colonised compost can successfully offset negative effects from high pH and EC as well as limited nutrient supply (and nitrogen immobilisation) in peat-free, compost-based growing media.

Effects of wine-cap Stropharia cultivation on soil nutrients and bacterial communities in forestlands of northern China

Background

Cultivating the wine-cap mushroom (Stropharia rugosoannulata) on forestland has become popular in China. However, the effects of wine-cap Stropharia cultivation on soil nutrients and bacterial communities are poorly understood.

Methods

We employed chemical analyses and high-throughput sequencing to determine the impact of cultivating the wine-cap Stropharia on soil nutrients and bacterial communities of forestland.

Results

Cultivation regimes of Stropharia on forestland resulted in consistent increases of soil organic matter (OM) and available phosphorus (AP) content. Among the cultivation regimes, the greatest soil nutrient contents were found in the one-year interval cultivation regime, and the lowest total N and alkaline hydrolysable N contents were observed in the current-year cultivation regime. No significant differences were observed in alpha diversity among all cultivation regimes. Specific soil bacterial groups, such as Acidobacteria, increased in abundance after cultivation of Stropharia rugosoannulata.

Discussion

Given the numerous positive effects exerted by OM on soil physical and chemical properties, and the consistent increase in OM content for all cultivation regimes, we suggest that mushroom cultivation is beneficial to forest soil nutrient conditions through increasing OM content. Based on the fact that the one-year interval cultivation regime had the highest soil nutrient content as compared with other cultivation regimes, we recommend this regime for application in farming practice. The spent mushroom compost appeared to be more influential than the hyphae of S. rugosoannulata on the soil nutrients and bacterial communities; however, this requires further study. This research provides insight into understanding the effects of mushroom cultivation on the forest soil ecosystem and suggests a relevant cultivation strategy that reduces its negative impacts.

Earthworm Grazed-Trichoderma harzianum Biofortified Spent Mushroom Substrates Modulate Accumulation of Natural Antioxidants and Bio-Fortification of Mineral Nutrients in Tomato

The present investigation was aimed at evaluating the impact of earthworm grazed and Trichoderma harzianum biofortified spent mushroom substrate (SMS) on natural antioxidant and nutritional properties of tomato. Results of the investigation reveal that earthworm grazing and T. harzianum bio-fortification led to significant improvement in the physico-chemical properties of fresh SMS and its application increased the accumulation of natural antioxidants and mineral content in tomato as compared to either T. harzianum biofortified SMS or fresh SMS. In particular, the earthworm grazed, T. harzianum biofortified SMS (EGTHB-SMS) was found to inhibit lipid peroxidation and protein oxidation with significant increase in total polyphenol and flavonoid content in tomato. Further, it increased Fe2+/Fe3+ chelating activity, superoxide anion radical scavenging activity compared to other treatments. The results thus suggest an augmented elicitation of natural antioxidant properties in tomato treated with EGTHB-SMS, resulting in a higher radical scavenging activity, that is highly desirable for human health. In addition, the use of SMS to enhance the nutritional value of tomato fruits becomes an environment friendly approach in sustainable crop production.

Spent mushroom waste as a media replacement for peat moss in Kai-Lan (Brassica oleracea var. Alboglabra) production

Peat moss (PM) is the most widely used growing substrate for the pot culture. Due to diminishing availability and increasing price of PM, researchers are looking for viable alternatives for peat as a growth media component for potted plants. A pot study was conducted with a view to investigate the possibility of using spent mushroom waste (SMW) for Kai-lan (Brassica oleracea var. Alboglabra) production replacing peat moss (PM) in growth media. The treatments evaluated were 100% PM (control), 100% SMW, and mixtures of SMW and PM in different ratios like 1 : 1, 1 : 2, and 2 : 1 (v/v) with/without NPK amendment. The experiment was arranged in a completely randomized design with five replications per treatment. Chemical properties like pH and salinity level (EC) of SMW were within the acceptable range of crop production but, nutrient content, especially nitrogen content was not enough to provide sufficient nutrition to plant for normal growth. Only PM (100%) and SMW and PM mixture in 1 : 1 ratio with NPK amendment performed equally in terms of Kai-lan growth. This study confirms the feasibility of replacing PM by SMW up to a maximum of 50% in the growth media and suggests that NPK supplementation from inorganic sources is to ensure a higher productivity of Kai-lan.