Oudemansiella aparlosarca is an edible mushroom possessing medicinal and health benefits. Although there are studies on the cultivation of O. aparlosarca, only a few studies have focused on its genetics and life cycle. Therefore, the main objective of this study was to identify the nuclear conditions of basidiospores and homokaryotic and heterokaryotic hyphal cells and to determine the influence of different nuclear conditions on basidiospore diameter in O. aparlosarca. Two parental strains: strain‐55 and strain‐81 were used. Staining of basidiospores and hyphal cells in the apical region was performed. We observed the following nuclear conditions: non‐nucleate, mononucleate, binucleate, and multinucleate. In both parental strains, binucleate spores were predominant, while the number of non‐nucleate spores was the lowest. The diameter of non‐nucleate spores was the smallest, being 11.52 µm and 12.15 µm in parental strain‐81 and strain‐55, respectively, while multinucleate spores had the largest diameter, being 14.78 µm in both parental strains. Both homokaryotic and heterokaryotic strains were identified in isolated single spores from parental strains. Binucleate cells were majorly present in heterokaryotic hyphal cells, and multinucleate cells were predominant in homokaryotic hyphal cells. We conclude that O. aparlosarca contains homokaryotic and heterokaryotic basidiospores, which indicates an amphithallic life cycle. The observed binucleate spores might be the result of post‐meiotic mitosis.

Fungal endophytes are an endosymbiotic group of fungi that live asymptomatically in healthy tissues of plants and macroalgae. Due to their ability to produce bioactive compounds with potential antifungal properties, fungal endophytes that inhabit seaweed have gained significant attention in the search for sustainable biocontrol agents against phytopathogenic fungi and bacteria. The present study is aimed at identifying fungal endophytes that reside inside seaweeds found in the coastal waters of Southern Province, Sri Lanka, and investigating their biocontrol potential against two fungal phytopathogens; Neopestalotiopsis cubana (Sporocadaceae, Amphisphaeriales) and Colletotrichum siamense (Glomerellaceae, Glomerellales). This is the first study to discover fungal endophytes associated with seaweeds found in the waters of Sri Lanka. Eight fungal endophytic strains were isolated from seaweeds; Padina antillarum (Dictyotaceae), Sargassum ilicifolium (Sargassacea), and Ulva lactuca (Ulvophyceae), found in Thalpe, Madiha, and Koggala beaches. Based on ITS-rDNA sequence analyses, they were preliminarily identified as four distinct endophytic fungal species belonging to the genera Aspergillus and Penicillium. Isolated fungal endophytes were tested for their biocontrol potential against two selected fungal pathogens using a dual culture assay. Percent growth inhibition (PI) of the test pathogens was calculated. Among the isolated fungal endophytes, Aspergillus sp. GMBUCC 24–013 showed the strongest antagonistic activity against both C. siamense UKCC 24-012 and N. cubana GMBUCC 24–001 closely followed by Aspergillus sp. GMBUCC 24–007, GMBUCC 24–008, GMBUCC 24–009, and GMBUCC 24–012. Aspergillus sp. GMBUCC 24–006 exhibited the least biocontrol potential against both phytopathogens, while Penicillium sp. GMBUCC 24–010, and GMBUCC 24–011 showed moderate activity.

Purpose: Water footprint (WFP) is a widely used environmental indicator to compare and identify the strategies for better water use efficiency. The Objectives of the present study were to calculate and analyze the WFP of Oyster mushroom cultivation under small-scale farming conditions in Sri Lanka. Research Method: Water footprint was estimated as the sum of water used for preparing the mushroom growing substrate and the on-farm water requirement for the production of a ton of mushrooms. Production parameters and on-farm water usage of three small-scale Oyster mushroom farms were recorded. Findings: WFPs of growing substrates were low (591 - 642 m3/ton) and varied within a narrow range. The main on-farm water-consuming activities were the preparation of growing media, water for sterilization of media, spraying of water during the growing cycle, floor cleaning, and laborer’s water consumption. WFP of mushroom cultivation under the conditions specified in this study was 1181 m3/ton. Being the largest component, mushroom growing media accounted for 95% of the WFP. On-farm water requirement was found to be as low as 4.4 L/kg. WFP of mushrooms was lower than those reported for eggs, broiler meat, pork, beef, lentil, and soy meat. Nevertheless, the WFP of mushrooms, when expressed per unit of calorie or protein was higher than that of egg and soy meat. Originality/ Value: As the first reported WFP calculation for mushrooms in Sri Lanka, this study identified mushrooms as a water-efficient food item. Improvement in yield and shortening of the growing cycle were identified as the means of reducing the WFP of mushroom cultivation in Sri Lanka.

The objective of the study was to identify the potential for soil C sequestration associated with the establishment of a botanical garden in the tropics. Since forest resources are dwindling and home gardens are limited botanical gardens could play a major role in mitigating CO₂ in the urban environment. This study determined C sequestration and nutrient availability of different thematic areas of a botanical garden 10 years after establishment in comparison with the primary land use, a dry zone forest at the establishment. The establishment of the botanical garden has created a significant improvement of the soil properties with compared to the primary land use. The soil C stocks were significantly high in the botanical garden with compared to the primary land use (7.3 t ha⁻¹). Thematic areas such as Arboretum Part B (13.04 t ha⁻¹), Herbal Garden (12.5 t ha⁻¹) and Valley path (13.23 t ha⁻¹) contained the highest amount of C in soil. Management practices used in maintaining this botanical garden may have affected the soil organic carbon and nutrient status of soil. This study showed that botanical gardens established in urban areas have a great capacity to store C and thereby to mitigate global warming.