Spatial and Seasonal Distribution of Endomycorrhiza from Cashew Nut in Bali

Plants growing in poor soil areas are commonly associated with endomycorrhizalfungi as a mutualism symbiotic. The fungus takes a role on enhancement water from the soil and uptake soil mineral particularly Phosphorus, Magnesium and Potassium. Poor soil conditions at Bali Island are spatially located at Gerokgak-Buleleng Suburb (Northwest of Bali) and Sukadana-Karangasem Suburb (North-East of Bali). One of the economical plants growing well at the regions is cashew nut plant. However, less study on the endomycorrizhal fungi associated with cashew nut plat has been undertaken. The objective of this study is to observe the spatial and temporal variation of VAM presence at the cashew nut planting area, consisting of number of spores and percentage of infection (colonization) at Cashew nut plant root. The number of spores was counted by wet sieving and decanting methods and the root infection were observed by means of Grid-line Intersect method. The result showed that the cashew nut plant at both regions live symbiotic mutually with VAM. The VAM spore density in cashew nut rizhospher shows either temporal or spatial variation. The spore density in Rizhospher tend to increase over dry season (June up to December) and decrease over raining season (April up to June and December up to February). The spore density is considerably higher in rizhosphere at Sukadana region than those at Gerokgak region. Such spatial variation seems likely related to the soil properties. The VAM colonization was found as vesicle, urbuscle, internal-external hyphae and spore forms. The VAM colonization shows similar temporal variation at both areas, it is considerably related to the temporal variation of rain fall level. Percentage of VAM colonization over raining season (April up to June and December up to February) is higher than over dry season (June up to December). Such VAM colonization, nevertheless, does not show spatial variation.