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Endomycorrhizas or arbuscular mycorrhizal fungi (AMF) are microfungal associates known to facilitate nutrient absorption in higher plants that benefit growth and survival. Studies have shown that they can induce systemic host resistance against pathogenic fungi, but little information is known about its contributions to gall rust disease in Falcataria moluccana, an important plantation tree species. This paper investigated the community of endomycorrhizas under F. moluccana stand affected by Uromycladium rust from a secondary-growth forest in Laguna, Philippines. Three transects (1.5 km) were established wherein matured F. moluccana trees (n = 32) were assessed for gall rust incidence and disease severity index (DSI) using a five-point rating scale to categorize infection. Composite rhizosphere samples were collected from nine sampling plots for macronutrient analysis and AMF assessment. Endomycorrhizal spores were isolated from dissolved 100-g soil solution following wet-sieving and decanting method then characterized morphologically for identification, spore density, and diversity analysis. Results of the tree health survey showed 100% disease incidence with moderate infection (DSI = 30–44). Overall, 13 morphospecies of endomycorrhizal fungi were identified from three orders and five families. The eight genera associated with F. moluccana were Acaulospora, Ambispora, Diversispora, Enthrophospora, Funneliformis, Gigaspora, Glomus, and Rhizophagus. The Shannon diversity index (H’) revealed a significant (p< 0.002) difference in all sites [F (2, 31) = 7.46]. The findings suggest that species abundance and density of AMF fungi are related to soil phosphorous and the severity of gall rust. This study presents the potential of important AMF species for the integrated management of gall rust disease affecting F. moluccana.

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The diversity of plant and mycorrhizal fungi within the 35,000-ha of the Atlas Mines in Toledo, Cebu, was surveyed with the goal of rehabilitating their mined-out area through bioremediation (the use of dominant plants and mycorrhizal fungi present in area to contain/reduce pollutants). From five one km transect lines in five sites, the survey indicated that the vegetation was classified as a disturbed grass-shrubland-savanna-agroforest plant community with tree plantations in rehabilitated sites. Plant composition comprised 69 species belonging to 66 genera and 35 families which include trees, shrubs, herbs, creepers, vines, agricultural or agroforest crops. Fruit bodies of ectomycorrhizal fungi (ECMF), namely: Pisolithus, Scleroderma, Thelephora and Boletellus were found under Acacia auriculiformis, A. mangium, Eucalyptus urophylla and E. camaldulensis. Pisolithus were the most dominant. For arbuscular mycorrhizal fungi (AMF), out of 50 plants collected, 10-100% roots of Lycopodium, Saccharum spontaneum, Nephrolepsis, Acacia mangium and Stachytarpheta jamaicensis were colonized by AMF. All roots of S. jamaicensis were colonized solely by Glomus sp. Pithecellobium dulce harboured the highest spore density (2,575 spores/plant/30g dry soil), consisting of Glomus (42%), Acaulospora (24%) and Entrophospora (37%). Muntingia calabura was the only plant associated with Glomus, Gigaspora, Scutellospora, Acaulospora and Entrophospora, though with low spore population. Glomus was the most prevalent among the AMF. The above AMF and ECMF can be mass-produced as biofertilizers for use in bioremediation of mined-out sites and other areas with similar conditions.

The species composition, physiognomy and importance value of PagbilaoMangrove, a typical satoumi site in southern Luzon, Philippines was determinedfrom May 2009 to August 2010. Vegetation analysis was done within a 20x20mquadrat established in each of the landward, middleward and seaward zones.A total of 37 species were identified in all zones comprising 744 individualsbelonging to 28 genera and 18 families.  Using Shannon Index of diversity, thelandward zone has the highest diversity followed by the seaward zone. The leastdiverse was the middleward zone.   There was a similar trend in the proportion ofvarious tree heights and diameter in seaward, middleward and landward zones.The density of small trees was higher than those of the big ones.  The IV ofthe species varied within the zones. In the order of decreasing IV A. marina> A. floridum >  Sonneratia alba in seaward zone.  In the middleward zone, A.officinalis > C. decandra  > S. hydrophyllacea. At the landward zone, X. granatum> A. officinalis > R. mucronata > A. marina var. rumphiana. The current floristiccomposition of Pagbilao mangrove indicates that this ecosystem is still diversebased on the number and kinds of species present. With the satoumi frameworkin place, there is much hope in the conservation and management of thismangrove ecosystem.Keywords: Ecology, mangrove, floristic composition, physiognomy, species composition,physiognomy, importance value, descriptive design, Philippines

Rehabilitation was conducted in an abandoned copper mined-out area in Mogpog, Marinduque by interplanting Jatropha curcas, a biodiesel source and potential phytoremediator, with different reforestation tree species, Pterocarpus indicus, Cassia spectabilis, Lagerstroemia speciosa and Bauhinia purpurea. The effect of the diversification treatment on the rhizosphere bacterial population, known to promote growth of host plant, was analyzed within a fifteen-month period (August 2007 to November 2008). The number of cultivable soil bacteria on-site prior to planting was very low (<0.01 to 2 x 103 CFU per g) owing to soil’s acidity (pH 5) and poorly nourished condition. Higher bacterial population was observed from Jatropha rhizosphere than soil without vegetation. Bacterial population also varied with diversification treatments. Highest populations (7.3 x 104 to 1.3 x 105 CFU per g) of Cu-, Pb- and Zn resistant bacteria were observed where in Jatropha was interplanted with Pterocarpus, Cassia, and Lagerstroemia. It appears that such treatment enhanced the population of heavy metal-resistant rhizosphere bacteria in Jatropha indicative of its potential in bioremediation. Randomly selected isolates were identified as Arthrobacter oxydans, Klebsiella variicola and Bacillus spp, which are all common soil bacteria. Rehabilitation of abandoned, mined-out areas can thus be naturally promoted by diversifying plants being introduced in such sites as this would enhance rhizosphere bacterial population.

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