Arbuscular Mycorrhizal Fungal Communities Are Influenced by Host Tree Species on the Loess Plateau, Northwest China

Mycorrhizae in mine wasteland reclamation

Mycorrhizae are found on about 70-80 % of the roots of all plant species; ectomycorrhizae (ECM) are mostly found on woody plants and gymnosperms, whereas arbuscular mycorrhizal fungi (AMF) are found on 80-90 % of all plant species. In abandoned mining sites, woody plants dominate, while non-woody species remain scarce. However, this pattern depends on the specific mine site and its ecological context. This review article explores the potential of using mycorrhizae-plant associations to enhance and facilitate the remediation of mine wastelands and metal-polluted sites. In this review, we employed reputable databases to collect articles and relevant information on mycorrhizae and their role in plant growth and soil fertility spanning from the 1990s up to 2024. Our review found that the abilities of plants selected for minewasteland reclamation can be harnessed effectively if their mycorrhizae utilization is known and considered. Our findings indicate that AMF facilitates plant cohabitation by influencing species richness, feedback effects, shared mycelial networks, and plant-AMF specificity. Several types of mycorrhizae have been isolated from mine wastelands, including Glomus mosseae, which reduces heavy metal accumulation in plants, and Rhizophagus irregularis, which enhances plant growth and survival in revegetated mine sites. Additionally, studies on ECM in surface mine spoil restoration stands highlight their role in enhancing fungal biodiversity and providing habitats for rare and specialized fungal species. Recent research shows that ECM and AMF fungi can interact synergistically to enhance plant growth, with ECM improving plant nitrogen absorption and AMF increasing nitrogen use efficiency. Our review also found that despite their critical role in improving plant growth and resilience, there remains limited knowledge about the specific mechanisms by which mycorrhizae communicate with each other and other microorganisms, such as bacteria, root-associated fungi, soil protozoa, actinomycetes, nematodes, and endophytes, within the soil matrix. This article highlights the connection between mycorrhizae and plants and other microorganisms in mine wastelands, their role in improving soil structure and nutrient cycling, and how mycorrhizae can help restore soil fertility and promote plant growth, thus improving the overall environmental quality of mine wasteland sites.

Socio-administrative conservation and collection practices of the sacred Thal Kedar forest, Uttarakhand, India

The long-lasting association of humans with the forest is directly linked to the livelihood of natives without cultures, traditions, and beliefs. A survey conducted for the phytodiversity of the sacred Thal Kedar forest, Uttarakhand, India, reveals it as a center of spiritual approach and controlled by moral values rather than regulatory norms for conservation and sustainable benefits. Detailed investigation via group discussions, key informant interviews, observation of participants, and secondary data collection deciphers that the sacred forest plays a potential role in the food and health of the people, both at the local and regional levels. In the present survey, we found that local people are effectively controlled and guided to use all resources through moral duty, beliefs, and worship rituals, an inherited practice for ecological protection, and honesty to the Deity. Forest tourism based on holy baths, a current social demand, has been emerging as a sustainable job for local youths but requires stringent parallel administrative supervision along the established social norms to avoid any materialistic mind deeds to the sacred forest. The impact of climate change and the shift of various species to higher elevations is a matter of advanced strategy to the policymakers to preserve the floristic diversity of the sacred Thal Kedar forest.

Mycorrhizal Colonization Enhanced Sorghum bicolor Tolerance under Soil Water Deficit Conditions by Coordination of Proline and Reduced Glutathione (GSH)

Drought stress is an important limiting factor in crop production. Arbuscular mycorrhizal fungi (AMF) enhance plant drought tolerance through antioxidant activities. However, the coordination of nonenzymatic antioxidants against drought remains unclear. Here, we investigated the AMF symbiosis in drought tolerance of Sorghum bicolor by increasing proline and reducing glutathione (GSH). Glomus mosseae inoculation increased grain yield, biochemical content, and bioactivities of millets. Under drought conditions, seedlings inoculated with G. mosseae had higher SOD, POD, CAT, PPO, proline, and GSH activities compared to noninoculated controls. Meanwhile, a lower accumulation of MDA and H₂O₂ was observed in the G. mosseae seedlings. Furthermore, genes attributed to nonenzymatic antioxidants, such as GST29, P5CS2, FD3, GST, and GAD, were significantly up-regulated by G. mosseae under drought conditions. In conclusion, G. mosseae inoculation enhanced the drought tolerance of S. bicolor by improving reactive oxygen species (ROS) scavengers, including proline and GSH, that regulate ROS production and prevent oxidative damage.

Alterations in Arbuscular Mycorrhizal Community Along a Chronosequence of Teak (Tectona grandis) Plantations in Tropical Forests of China

Arbuscular mycorrhizal (AM) fungi play a crucial role in promoting plant growth, enhancing plant stress resistance, and sustaining a healthy ecosystem. However, little is known about the mycorrhizal status of teak plantations. Here, we evaluated how the AM fungal communities of rhizosphere soils and roots respond to different stand ages of teak: 22, 35, 45, and 55-year-old from the adjacent native grassland (CK). A high-throughput sequencing method was used to compare the differences in soil and root AM fungal community structures. In combination with soil parameters, mechanisms driving the AM fungal community were revealed by redundancy analysis and the Mantel test. Additionally, spore density and colonization rates were analyzed. With increasing stand age, the AM fungal colonization rates and spore density increased linearly. Catalase activity and ammonium nitrogen content also increased, and soil organic carbon, total phosphorous, acid phosphatase activity, available potassium, and available phosphorus first increased and then decreased. Stand age significantly changed the structure of the AM fungal community but had no significant impact on the diversity of the AM fungal community. However, the diversity of the AM fungal community in soils was statistically higher than that in the roots. In total, nine and seven AM fungal genera were detected in the soil and root samples, respectively. The majority of sequences in soils and roots belonged to Glomus. Age-induced changes in soil properties could largely explain the alterations in the structure of the AM fungal community along a chronosequence, which included total potassium, carbon-nitrogen ratio, ammonium nitrogen, catalase, and acid phosphatase levels in soils and catalase, acid phosphatase, pH, and total potassium levels in roots. Soil nutrient availability and enzyme activity were the main driving factors regulating the shift in the AM fungal community structure along a chronosequence of the teak plantations.

Efforts of Indigenous Knowledge in Forest and Wildlife Conservation: A Case Study on Bulang People in Mangba Village in Yunnan Province, China

In rural areas, indigenous knowledge plays an important role in the protection of forests and wildlife, but the rapid developments occurring in the society and economy impose several challenges to the continued role of indigenous knowledge. This study records how a Bulang village in the Yunnan Province of China uses indigenous knowledge to protect forests and wildlife and analyzes the underlying reasons. In this study, we found that even without specific punishment measures, local people effectively controlled the use of natural resources through moral constraints, public-opinion constraints, and worship rituals. Furthermore, they formed a forest- and wildlife-protection system with banyan trees and the Derbyan Parakeet at the core. This protection system is based on primitive nature worship and indigenous knowledge passed down orally from generation to generation. Such knowledge inheritance reflects the relationship between local people and nature. However, the lack of scientific guidance regarding ecological protection may lead to the destruction of the ecosystem. One such instance is illustrated using birdwatching tourism, for which the Bulang people are attracting birds by artificial feeding. This practice, while prescribed by indigenous knowledge, deviates from scientific knowledge on ecological protection. Therefore, we propose that there should be an intermeshing of indigenous and scientific knowledge to ensure the inheritance of and innovation in the former and effective biodiversity protection.