ROLE OF SYMBIOTIC SOIL FUNGI IN CONTROLING ROAD SIDE EROSION AND IN THE ESTABLISHMENT OF PLANT COMMUNITIES

Mycorrhizal fungi are an important component of the rhizosphere of a vast majority of plants. The fungi form mutually beneficial relationship with the roots of these plants. These associations are often obligatory but can be facultative. The benefits conferred to host plants are Increased nutrient (minerals, etc.) uptake, e.g., Phosphorus, Potassium, etc.), increased water availability, Increased tolerance to pH and temperature, growth factors (from fungus) enhances / influences root development, Increased longevity of feeder roots, better rhizosphere development and protection of feeder roots from pathogen. The benefits to mycobiont are carbohydrate food for fungus in most cases (exception orchid mycorrhizae), plant roots release /secrete vitamins (thiamine, etc.) and "Factors"-stimulate spore germination & hyphal growth. Four different stands in the Nothern areas of Pakistan were sampled and analysed using simple ecological methods. The stands sampled were situated in Nalter and Astore, Gilgit. The stands included undisturbed natural vegetation stands and disturbed stands. The disturbed stands were characterized by excessive cutting and felling of trees and overgrazing leading to entirely changed picture of the plant communities and associated mycoflora. For mycological studies the roots of plants of the above mentioned stands along with the rhizosphere soil were sampled and processed. It was recorded that the types of ectomycorrhizal fungi varied as the forest stands matured. The fungi almost trend to disappear when the forest trees are cut. The number of root tips with ectomycorrhizae decreased when the stands were disturbed. So was the case with vesicular arbuscular mycorrhiza forming endogonaceous spores number. The weight of water stable aggregates also reduced in the soils of disturbed stands. These disastrous situations then end up with removal of rest of the forest vegetation and excessive erosion or removal of top fertile soil. This can be avoided with proper management of these fungi