Acacia mangium and Eucalyptus urophylla are popular species for forest plantation and known for t... more Acacia mangium and Eucalyptus urophylla are popular species for forest plantation and known for their rehabilitation capability on heavy metal sites. The experiment was conducted to determine the effect of soil inoculants such as arbuscular mycorrhizal fungi (AMF) and nitrogenfixing bacteria (NFB) on growth, nutrient accumulation, and microbial population of both species under field conditions. The NFB inoculant with Azospirillum was produced at BIOTECH UPLB. The seedlings inoculated with AMF from Surigao, Mindanao mine tailing (coded as Sur) with or without NFB were raised at the screenhouse and planted in mine tailing site of Mogpog, Marinduque. After 27 mo, the highest height increment (202.5 cm) was noticed on A. mangium (126 cm) and on E. urophylla under Sur inoculation alone. The highest stem diameter increment of A. mangium (54.7 cm) was observed in Sur+NFB while for E. urophylla (29.9 cm) it was observed in Sur alone. Shoot and root dry weights of both species were highest in Sur. Total N uptake of both plants and P uptake of E. urophylla was highest in Sur inoculant while the P in A. mangium was highest in Sur+NFB treatment. Sur+NFB inoculated plants gave the highest population of NFB with highly significant effect in A. mangium while Sur alone accumulated the highest NFB in E. urophylla but with no significant effect on Sur+NFB and control counterpart. Mycorrhizal spore count of both plants were highest in Sur, while the highest percent root colonization in A. mangium was observed with Sur inoculation and with Sur+NFB inoculation in E. urophylla. Correlation analysis among growth, nutrient, and microbial parameters were also obtained. Root colonization and spore count in A. mangium were highly correlated. On the other hand, a high correlation between plant dry weight and root dry weight was obtained in E. urophylla. The response of both species to mycorrhizal inoculation provides a useful criterion in selecting plant species that can be used in revegetation of mined-out areas and other degraded lands throughout the country.
... p. 1. Abstract (English), Tons of toxic and hazardous wastes generally from industries in add... more ... p. 1. Abstract (English), Tons of toxic and hazardous wastes generally from industries in addition to existing dump sites like abandoned mines that harbor high levels of pollutants are generated continuously. While some industries ...
Arbuscular mycorrhizal fungi (AMF) play a significant role for mine tailing rehabilitation due to... more Arbuscular mycorrhizal fungi (AMF) play a significant role for mine tailing rehabilitation due to their sensitivity towards a range of soil pollutants. This beneficial biological agent can enhance plant tolerance to heavy metal contamination. This study screened indigenous AMF associated with growing indigenous ferns and grasses in the mine tailings for potential use in rehabilitating a 3-decade abandoned mined out area in Mogpog, Marinduque. Pterocarpus indicus Willd. (narra) was used as the host plant to establish mycorrhizal fungi association. Among the treatments, indigenous AMF associated with Ferns 1, 2 and 5 generally improved the height and shoot diameter of the narra seedlings and the effect was comparable with commercially available AMF inoculants, MYKOVAM ® and MYKORICH ®. The dry weight of the roots and nodules was consistently improved by indigenous AMF from Fern2 and Grass1, which had comparable effect with MYKOVAM ® and MYKORICH ®. Overall, the total seedling dry matter of narra seedlings was significantly stimulated by AMF, irrespective of isolates' origin. The mycorrhizal root infection by AMF and number of spores in the soil were all high as compared with the uninoculated control counterpart. Lastly, AMF inoculation induced Cu retention in the roots of the seedlings. Thus the results imply that, the mined out indigenous AMF are potential agents to rehabilitate the abandoned mine tailings in the Philippines.
This study determined the influence of varying soil amendments containing bamboo biochar (BB) wit... more This study determined the influence of varying soil amendments containing bamboo biochar (BB) with or without biofertilizers on the populations of arbuscular mycorrhizal fungi (AMF) and nitrogen-fixing bacteria (NFB), on plant growth, and soil parameters in acidic soil under nursery conditions. Cacao var. UF18 were sown in polypropylene bags filled with a 200-g oven- sterilized soil-sand mixture. After a month, cacao seedlings were transferred to a mixture of unsterilized acidic soil (4.65 pH) and vermicompost (3:1, w/w) and amended with BB (w/w) at varying concentrations (0, 15, and 30%). Inoculation with available formulated AMF inoculants (AMF1 and AMF2) and NFB, singly and in combination, was also done during this stage by adding the recommended rates directly beneath the roots. The results showed that regardless of biochar concentration and the type of AMF inoculum used, there was a significant decrease in AMF spore count and root colonization when AMF and NFB were combined. Root colonization in cacao by AMF1 or AMF2 showed no significant difference from each other. In general, the amendment of BB could have resulted in better soil properties such as increased pH, nitrogen (N), and phosphorus (P), which provided a condition where microorganisms can optimally grow. However, co-inoculation of AMF and NFB resulted in a decrease in both spore count and root colonization, suggesting possible adverse interaction between the microorganisms. Co-amendment of 15% BB and biofertilizer (NFB or AMF1 alone) resulted in heavier (140 and 130 g plant–1) plant biomass compared with single inoculation of BB or biofertilizer (50–90 g plant–1). Moreover, the highest N uptake (2257 mg plant–1) was observed in cacao plants inoculated with NFB grown in 15% BB-amended soil. Cacao seedlings inoculated with NFB and AMF1 and amended with 15% BB soil resulted in the highest uptake of P (537 and 539 mg plant–1, respectively). The results clearly showed the beneficial effects of combining biofertilizer and BB at 15% concentration as compared to 0 and 30%. It is recommended that the same treatments be done in a field study to verify the results obtained in the nursery experiments.
Poor soil health adversely affects farming and forestry sectors worldwide. Microbial fertilizers ... more Poor soil health adversely affects farming and forestry sectors worldwide. Microbial fertilizers can improve the plant-soil continuum in degraded ecosystem. In this research, the soil microbiome, plant biomass and root-shoot ratio of 2 mo-old Bauhinia purpurea, transplanted on aseptic soil + sand mixture (1:1) upon inoculation with 5 g of AMF (MYKOCAP®, coded as MCAP and MYKORICH®, coded as MRICH), with or without NFB (Bio-NTM, coded as Bio-N) amendment, were investigated. B. purpurea (Fabaceae), is an important reforestation and fodder species for livestock. The total plant biomass ranged from 18.90 g - 23.33 g, and highest in MRICH. Root-shoot ratio in Bio-N (0.58) was 23.4% higher than the Control. MCAP and Bio-N had increased sporulation and root colonization and NFB communities, respectively. Spore count can explain 32.9% change in primary roots biomass (p=0.013, r2=0.573), while root colonization can explain the 28.3% (p=0.023, r2=0.532), 47.9% (p=0.001, r2=0.692), 48.7% (p=0.001, r2=0.698), 26.5% (p=0.029, r2=0.514), and 39.4% (p=0.005, r2=0.628) change in total biomass, stem biomass, shoot biomass, primary roots biomass, and root biomass, respectively. Microbial fertilizers had increased the biomass and root-shoot ratio of B. purpurea, 90 days after inoculation. Microbial technology and multipurpose tree-based agroforestry are promising biological solutions for degraded agroforest ecosystems.
Journal of Environmental Science and Management, Jun 30, 2015
The diversity of plant and mycorrhizal fungi within the 35,000-ha of the Atlas Mines in Toledo, C... more 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.
A comparative study was done to determine the growth, microbial population, and physico- chemical... more A comparative study was done to determine the growth, microbial population, and physico- chemical properties on UF18 cacao (Theobroma cacao) seedlings when treated with chemical fertilizers and biofertilizers, either applied singly or in combination. The experimental design was randomized completely block design with five seedlings per treatment per block. Treatments used were: control, ½ recommended rate of chemical (RRC) fertilizer, RRC, MYKORICH®, MYKOCAP®, ½ RRC + MYKORICH®, ½ RRC + MYKOCAP®, RRC + MYKORICH®, and RRC + MYKOCAP®. MYKORICH® and MYKOCAP® contain 12 species of arbuscular mycorrhizal fungi isolated from stressed environments. The results showed that plant growth and physico-chemical properties were significantly improved by the application of biofertilizer than by chemical fertilizer. MYKORICH® treatment gave the highest spore count and is highly significant (p < 0.05) as compared to the other treatments with spore count ranging from 41–115.5/ 50 g soil. In terms of nitrogen-fixing bacteria count, ½ RRC treatment gave the highest (16.9 CFU x 10–5 g soil–1) bacterial count. RRC + MYKORICH® inoculation gave the highest values for most of the soil physico-chemical analysis (pH, P, K, and CEC). The positive response of cacao seedlings to mycorrhizal inoculation with or without chemical fertilizer provides a useful criterion in other agricultural lands throughout the country for crop production and sustainability.
Cacao diseases are an important aspect of cacao production that directly translates to losses and... more Cacao diseases are an important aspect of cacao production that directly translates to losses and yield. Arbuscular mycorrhizal fungi (AMF) are recently studied for their increasing role in disease resistance in many crops, including cacao. In this study, the effects of the different treatments of AMF and biochar applied singly or in combination on the incidence of pod rot diseases-especially the black pod disease-were investigated. Cacao trees were previously treated with AMF and/or biochar during their seedling stage; later, they were assessed for symptomatic pods, three years after field planting. The results showed that there was an interaction (p = 0.043) between treatment and cacao variety on disease incidence. In almost all instances, disease incidence was highest in the control (without AMF) setup as compared to the amended counterparts. For all varieties, except K2, disease incidence was the lowest on trees with added AMF and biochar amendments. Isolation of fungi associated with symptomatic pods was carried out. However, Phytophthora (the well-known pathogen of black pod disease) was not successfully isolated; hence, the occurrence of black pod disease was unconfirmed. Other fungal genera such as Fusarium, Colletotrichum, Pestalotiopsis, and Lasiodiplodia had the highest occurrence among the fungal isolates. The results from this study support the explored role of AMF associations on disease resistance and plant health on cacao plants in field conditions.
Bauhinia purpurea (belonging to Family Fabaceae-Leguminosae) is a small to medium-sized deciduous... more Bauhinia purpurea (belonging to Family Fabaceae-Leguminosae) is a small to medium-sized deciduous fast-growing tree that is very important in reforestation and agroforestry, and also used as fodder for livestock. This study investigated the influence of mycorrhizal inoculant with varying nitrogen-fixing bacteria (NFB) amendment levels on the growth performance of B. purpurea, the buildup of microbial communities in its rhizosphere soil, and root colonization in screenhouse conditions with UV plastic roofing, following a two-factor randomized complete block design. Factor 1 was the type of mycorrhizal inoculants applied on containerized seedlings grown in garden soil: AMF1 (MYKOCAP® or MCAP) and AMF2 (MYKORICH® or MRICH). Factor 2 was the rate of NFB (BioNTM) amendment (0 g, 5 g per seedling). At 90 d, MCAP + BioN treated plants were 37% taller than the MRICH + BioN treated ones (34 ± 0.50 cm). Seedlings with MCAP + BioN or MRICH + BioN had higher diameter increment; partitioned biomass from stems, lateral roots, and primary roots; root-shoot ratio; and root colonization than those without BioN and the control. Likewise, the NFB population was 276 and 126%, respectively higher with MCAP + BioN and MRICH + BioN than their counterparts without BioN. Contrarily, partitioned biomass from leaves, roots, and shoots, and the arbuscular mycorrhizal fungi (AMF) spore density were higher with AMF inoculants alone. Spore count was strongly positively correlated with primary root biomass (p = 0.013, r = 0.573), NFB buildup with height increment (p = 0.001, r = 0.708), and root colonization with diameter increment (p = 0.001, r = 0.805), total biomass (p = 0.023, r = 0.532), stem biomass (p = 0.001, r = 0.692), shoot biomass (p = 0.001, r = 0.698), primary root biomass (p = 0.029, r = 0.514), and root biomass (p = 0.005, r = 0.628). AMF and NFB symbiosis was inferred to have been developed, thereby promoting overall plant growth with an increased mycorrhizal root infection and NFB buildup, while the increased spore density contributed to enhanced primary root growth. Field verification trials must be conducted to determine the microbial fertilizer’s efficacy under abiotic and biotic stresses.
The study investigated the effects of a novel biochar-biofertilizer-vermicompost formulation on t... more The study investigated the effects of a novel biochar-biofertilizer-vermicompost formulation on the rhizosphere soil microbial community and growth of mature T. cacao trees planted in three farms in the provinces of Batangas (Lipa) and Laguna (Liliw and Magdalena), Philippines. Cacao trees were amended with MYKORICH® (MR) without or with 15% bamboo biochar (15% BB) and vermicompost. In the three years span of the experiment, stem diameter increments of BB-treated cacao in Magdalena and Lipa were 5% and 19% higher than the control (56.09 mm and 49.08 mm), respectively, whereas MR and MR + BB-treated trees in Liliw were 34-35% higher relative to control. Soil microbial analysis showed that mycorrhizal spore counts in BB-amended soils were 133% (Liliw), 262% (Magdalena) and 109% (Lipa) higher than the control. Nitrogen-fixing bacteria obtained from MR + BB-amended soils in Liliw were 216% higher than control, and 81% higher relative to control in BB-treated soils in Lipa. Soil nitrogen and potassium contents of the three cacao farms also improved by 26-85%. With the significant effect of bamboo biochar and mycorrhizal fertilizer, alone or in combination, on the growth of cacao, the microbial community and nutrient status of the cacao rhizosphere soil, this technology would be beneficial to cacao farmers and to almost all crops in an agroforest ecosystem.
Biotropia: The Southeast Asian Journal of Tropical Biology, Jun 1, 1995
To examine the effects of soil microbial population on mycorrhizal development and function, Euca... more To examine the effects of soil microbial population on mycorrhizal development and function, Eucalyptus urophylla seedlings were inoculated with two Pisolithus tinctorius isolates and grown in sterile, partly sterile and non-sterile soil. The two isolates of Pisolithus were an effective isolate (H445) collected from under eucalypts in Australia and an isolate (H615) collected from under eucalypts in the Philippines. Soils used were infertile acid soils collected from field sites in Pangasinan, Luzon and Surigao, Mindanao. In both soils, the Australian Pisolithus H445 improved the growth of E. urophylla seedlings more than Philippine isolate H615. The uninoculated seedlings exhibited stunted growth typical of P deficiency. Height at 8 weeks was significantly taller in sterile than in non-sterile soil. A significant interaction effect of inoculation and soil sterilization on height at harvest was observed only in Surigao soil. Soil sterilization had a varied effect on mycorrhizal formation. In Pangasinan soil, root colonization by H445 was significantly greater in non-sterile soil than in sterile soil. Whereas in Surigao soil, root colonization was significantly reduced by 54% from partly sterile to non-sterile soil. On the other hand, H615 showed significant mycorrhizal colonization in non-sterile soil compared from those in partly sterile and sterile soils. The degree of infection did not necessarily correspond to growth promotion in E. urophylla seedlings. These results indicate that the performance of the H445 was markedly affected by the microbial flora of the two soils. Thus, its potential use in the Philippines needs to be thoroughly tested in the field before its widespread use in any inoculation program.
To examine the effects of microbial populations and external phosphorus supply of two Philippine ... more To examine the effects of microbial populations and external phosphorus supply of two Philippine soils on mycorrhizal formation, Eucalyptus urophylla seedlings were inoculated with two Pisolithus isolates and grown in fumigated, reinfested and unfumigated soil fertilized with four rates of phosphorus. The Pisolithus isolates used were collected from under eucalypts in Australia and in the Philippines. Soils were infertile acid silty loams collected from field sites in Pangasinan, Luzon and Surigao, Mindanao. Significant interaction was observed between inoculation, soil fumigation and phosphorus supply on mycorrhizal formation by the Australian isolate in Surigao soil but not in Pangasinan soil. Soil fumigation enhanced mycorrhizal formation by the Australian isolate but did not affect root colonization by the Philippine isolate. Root colonization by the Australian isolate was highest in the reinfested soil while for the Philippine isolate it was highest in the unfumigated soil. The Australian isolate was more effective than the Philippine isolate in promoting growth and P uptake of E. urophylla seedlings in both soils. Total dry weight and P uptake of E. urophylla seedlings inoculated with the Australian isolate were maximum in fumigated and in the reinfested Pangasinan and Surigao soils supplied with 8 mg P kg-1 soil. In the unfumigated soil, growth of seedlings inoculated with the Australian isolate was significantly reduced. Seedlings inoculated with the Philippine isolate had the largest dry weights and P contents in unfumigated Pangasinan and Surigao soils supplied with 8 mg P kg-1 soil. These results indicate that the performance of the Australian Pisolithus isolate was markedly affected by biological factors in unfumigated soil. Thus, its potential use in the Philippines needs to be thoroughly tested in a variety of unfumigated soils before its widespread use in any inoculation programme.
Page 1. Growth response of Acacia mangium Willd. seedlings to arbuscular mycorrhizal fungi and fo... more Page 1. Growth response of Acacia mangium Willd. seedlings to arbuscular mycorrhizal fungi and four isolates of the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch Nelly Siababa Aggangan Æ Heung Kyu Moon Æ Sim Hee Han ...
Acacia mangium and Eucalyptus urophylla are popular species for forest plantation and known for t... more Acacia mangium and Eucalyptus urophylla are popular species for forest plantation and known for their rehabilitation capability on heavy metal sites. The experiment was conducted to determine the effect of soil inoculants such as arbuscular mycorrhizal fungi (AMF) and nitrogenfixing bacteria (NFB) on growth, nutrient accumulation, and microbial population of both species under field conditions. The NFB inoculant with Azospirillum was produced at BIOTECH UPLB. The seedlings inoculated with AMF from Surigao, Mindanao mine tailing (coded as Sur) with or without NFB were raised at the screenhouse and planted in mine tailing site of Mogpog, Marinduque. After 27 mo, the highest height increment (202.5 cm) was noticed on A. mangium (126 cm) and on E. urophylla under Sur inoculation alone. The highest stem diameter increment of A. mangium (54.7 cm) was observed in Sur+NFB while for E. urophylla (29.9 cm) it was observed in Sur alone. Shoot and root dry weights of both species were highest in Sur. Total N uptake of both plants and P uptake of E. urophylla was highest in Sur inoculant while the P in A. mangium was highest in Sur+NFB treatment. Sur+NFB inoculated plants gave the highest population of NFB with highly significant effect in A. mangium while Sur alone accumulated the highest NFB in E. urophylla but with no significant effect on Sur+NFB and control counterpart. Mycorrhizal spore count of both plants were highest in Sur, while the highest percent root colonization in A. mangium was observed with Sur inoculation and with Sur+NFB inoculation in E. urophylla. Correlation analysis among growth, nutrient, and microbial parameters were also obtained. Root colonization and spore count in A. mangium were highly correlated. On the other hand, a high correlation between plant dry weight and root dry weight was obtained in E. urophylla. The response of both species to mycorrhizal inoculation provides a useful criterion in selecting plant species that can be used in revegetation of mined-out areas and other degraded lands throughout the country.
... p. 1. Abstract (English), Tons of toxic and hazardous wastes generally from industries in add... more ... p. 1. Abstract (English), Tons of toxic and hazardous wastes generally from industries in addition to existing dump sites like abandoned mines that harbor high levels of pollutants are generated continuously. While some industries ...
Arbuscular mycorrhizal fungi (AMF) play a significant role for mine tailing rehabilitation due to... more Arbuscular mycorrhizal fungi (AMF) play a significant role for mine tailing rehabilitation due to their sensitivity towards a range of soil pollutants. This beneficial biological agent can enhance plant tolerance to heavy metal contamination. This study screened indigenous AMF associated with growing indigenous ferns and grasses in the mine tailings for potential use in rehabilitating a 3-decade abandoned mined out area in Mogpog, Marinduque. Pterocarpus indicus Willd. (narra) was used as the host plant to establish mycorrhizal fungi association. Among the treatments, indigenous AMF associated with Ferns 1, 2 and 5 generally improved the height and shoot diameter of the narra seedlings and the effect was comparable with commercially available AMF inoculants, MYKOVAM ® and MYKORICH ®. The dry weight of the roots and nodules was consistently improved by indigenous AMF from Fern2 and Grass1, which had comparable effect with MYKOVAM ® and MYKORICH ®. Overall, the total seedling dry matter of narra seedlings was significantly stimulated by AMF, irrespective of isolates' origin. The mycorrhizal root infection by AMF and number of spores in the soil were all high as compared with the uninoculated control counterpart. Lastly, AMF inoculation induced Cu retention in the roots of the seedlings. Thus the results imply that, the mined out indigenous AMF are potential agents to rehabilitate the abandoned mine tailings in the Philippines.
This study determined the influence of varying soil amendments containing bamboo biochar (BB) wit... more This study determined the influence of varying soil amendments containing bamboo biochar (BB) with or without biofertilizers on the populations of arbuscular mycorrhizal fungi (AMF) and nitrogen-fixing bacteria (NFB), on plant growth, and soil parameters in acidic soil under nursery conditions. Cacao var. UF18 were sown in polypropylene bags filled with a 200-g oven- sterilized soil-sand mixture. After a month, cacao seedlings were transferred to a mixture of unsterilized acidic soil (4.65 pH) and vermicompost (3:1, w/w) and amended with BB (w/w) at varying concentrations (0, 15, and 30%). Inoculation with available formulated AMF inoculants (AMF1 and AMF2) and NFB, singly and in combination, was also done during this stage by adding the recommended rates directly beneath the roots. The results showed that regardless of biochar concentration and the type of AMF inoculum used, there was a significant decrease in AMF spore count and root colonization when AMF and NFB were combined. Root colonization in cacao by AMF1 or AMF2 showed no significant difference from each other. In general, the amendment of BB could have resulted in better soil properties such as increased pH, nitrogen (N), and phosphorus (P), which provided a condition where microorganisms can optimally grow. However, co-inoculation of AMF and NFB resulted in a decrease in both spore count and root colonization, suggesting possible adverse interaction between the microorganisms. Co-amendment of 15% BB and biofertilizer (NFB or AMF1 alone) resulted in heavier (140 and 130 g plant–1) plant biomass compared with single inoculation of BB or biofertilizer (50–90 g plant–1). Moreover, the highest N uptake (2257 mg plant–1) was observed in cacao plants inoculated with NFB grown in 15% BB-amended soil. Cacao seedlings inoculated with NFB and AMF1 and amended with 15% BB soil resulted in the highest uptake of P (537 and 539 mg plant–1, respectively). The results clearly showed the beneficial effects of combining biofertilizer and BB at 15% concentration as compared to 0 and 30%. It is recommended that the same treatments be done in a field study to verify the results obtained in the nursery experiments.
Poor soil health adversely affects farming and forestry sectors worldwide. Microbial fertilizers ... more Poor soil health adversely affects farming and forestry sectors worldwide. Microbial fertilizers can improve the plant-soil continuum in degraded ecosystem. In this research, the soil microbiome, plant biomass and root-shoot ratio of 2 mo-old Bauhinia purpurea, transplanted on aseptic soil + sand mixture (1:1) upon inoculation with 5 g of AMF (MYKOCAP®, coded as MCAP and MYKORICH®, coded as MRICH), with or without NFB (Bio-NTM, coded as Bio-N) amendment, were investigated. B. purpurea (Fabaceae), is an important reforestation and fodder species for livestock. The total plant biomass ranged from 18.90 g - 23.33 g, and highest in MRICH. Root-shoot ratio in Bio-N (0.58) was 23.4% higher than the Control. MCAP and Bio-N had increased sporulation and root colonization and NFB communities, respectively. Spore count can explain 32.9% change in primary roots biomass (p=0.013, r2=0.573), while root colonization can explain the 28.3% (p=0.023, r2=0.532), 47.9% (p=0.001, r2=0.692), 48.7% (p=0.001, r2=0.698), 26.5% (p=0.029, r2=0.514), and 39.4% (p=0.005, r2=0.628) change in total biomass, stem biomass, shoot biomass, primary roots biomass, and root biomass, respectively. Microbial fertilizers had increased the biomass and root-shoot ratio of B. purpurea, 90 days after inoculation. Microbial technology and multipurpose tree-based agroforestry are promising biological solutions for degraded agroforest ecosystems.
Journal of Environmental Science and Management, Jun 30, 2015
The diversity of plant and mycorrhizal fungi within the 35,000-ha of the Atlas Mines in Toledo, C... more 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.
A comparative study was done to determine the growth, microbial population, and physico- chemical... more A comparative study was done to determine the growth, microbial population, and physico- chemical properties on UF18 cacao (Theobroma cacao) seedlings when treated with chemical fertilizers and biofertilizers, either applied singly or in combination. The experimental design was randomized completely block design with five seedlings per treatment per block. Treatments used were: control, ½ recommended rate of chemical (RRC) fertilizer, RRC, MYKORICH®, MYKOCAP®, ½ RRC + MYKORICH®, ½ RRC + MYKOCAP®, RRC + MYKORICH®, and RRC + MYKOCAP®. MYKORICH® and MYKOCAP® contain 12 species of arbuscular mycorrhizal fungi isolated from stressed environments. The results showed that plant growth and physico-chemical properties were significantly improved by the application of biofertilizer than by chemical fertilizer. MYKORICH® treatment gave the highest spore count and is highly significant (p < 0.05) as compared to the other treatments with spore count ranging from 41–115.5/ 50 g soil. In terms of nitrogen-fixing bacteria count, ½ RRC treatment gave the highest (16.9 CFU x 10–5 g soil–1) bacterial count. RRC + MYKORICH® inoculation gave the highest values for most of the soil physico-chemical analysis (pH, P, K, and CEC). The positive response of cacao seedlings to mycorrhizal inoculation with or without chemical fertilizer provides a useful criterion in other agricultural lands throughout the country for crop production and sustainability.
Cacao diseases are an important aspect of cacao production that directly translates to losses and... more Cacao diseases are an important aspect of cacao production that directly translates to losses and yield. Arbuscular mycorrhizal fungi (AMF) are recently studied for their increasing role in disease resistance in many crops, including cacao. In this study, the effects of the different treatments of AMF and biochar applied singly or in combination on the incidence of pod rot diseases-especially the black pod disease-were investigated. Cacao trees were previously treated with AMF and/or biochar during their seedling stage; later, they were assessed for symptomatic pods, three years after field planting. The results showed that there was an interaction (p = 0.043) between treatment and cacao variety on disease incidence. In almost all instances, disease incidence was highest in the control (without AMF) setup as compared to the amended counterparts. For all varieties, except K2, disease incidence was the lowest on trees with added AMF and biochar amendments. Isolation of fungi associated with symptomatic pods was carried out. However, Phytophthora (the well-known pathogen of black pod disease) was not successfully isolated; hence, the occurrence of black pod disease was unconfirmed. Other fungal genera such as Fusarium, Colletotrichum, Pestalotiopsis, and Lasiodiplodia had the highest occurrence among the fungal isolates. The results from this study support the explored role of AMF associations on disease resistance and plant health on cacao plants in field conditions.
Bauhinia purpurea (belonging to Family Fabaceae-Leguminosae) is a small to medium-sized deciduous... more Bauhinia purpurea (belonging to Family Fabaceae-Leguminosae) is a small to medium-sized deciduous fast-growing tree that is very important in reforestation and agroforestry, and also used as fodder for livestock. This study investigated the influence of mycorrhizal inoculant with varying nitrogen-fixing bacteria (NFB) amendment levels on the growth performance of B. purpurea, the buildup of microbial communities in its rhizosphere soil, and root colonization in screenhouse conditions with UV plastic roofing, following a two-factor randomized complete block design. Factor 1 was the type of mycorrhizal inoculants applied on containerized seedlings grown in garden soil: AMF1 (MYKOCAP® or MCAP) and AMF2 (MYKORICH® or MRICH). Factor 2 was the rate of NFB (BioNTM) amendment (0 g, 5 g per seedling). At 90 d, MCAP + BioN treated plants were 37% taller than the MRICH + BioN treated ones (34 ± 0.50 cm). Seedlings with MCAP + BioN or MRICH + BioN had higher diameter increment; partitioned biomass from stems, lateral roots, and primary roots; root-shoot ratio; and root colonization than those without BioN and the control. Likewise, the NFB population was 276 and 126%, respectively higher with MCAP + BioN and MRICH + BioN than their counterparts without BioN. Contrarily, partitioned biomass from leaves, roots, and shoots, and the arbuscular mycorrhizal fungi (AMF) spore density were higher with AMF inoculants alone. Spore count was strongly positively correlated with primary root biomass (p = 0.013, r = 0.573), NFB buildup with height increment (p = 0.001, r = 0.708), and root colonization with diameter increment (p = 0.001, r = 0.805), total biomass (p = 0.023, r = 0.532), stem biomass (p = 0.001, r = 0.692), shoot biomass (p = 0.001, r = 0.698), primary root biomass (p = 0.029, r = 0.514), and root biomass (p = 0.005, r = 0.628). AMF and NFB symbiosis was inferred to have been developed, thereby promoting overall plant growth with an increased mycorrhizal root infection and NFB buildup, while the increased spore density contributed to enhanced primary root growth. Field verification trials must be conducted to determine the microbial fertilizer’s efficacy under abiotic and biotic stresses.
The study investigated the effects of a novel biochar-biofertilizer-vermicompost formulation on t... more The study investigated the effects of a novel biochar-biofertilizer-vermicompost formulation on the rhizosphere soil microbial community and growth of mature T. cacao trees planted in three farms in the provinces of Batangas (Lipa) and Laguna (Liliw and Magdalena), Philippines. Cacao trees were amended with MYKORICH® (MR) without or with 15% bamboo biochar (15% BB) and vermicompost. In the three years span of the experiment, stem diameter increments of BB-treated cacao in Magdalena and Lipa were 5% and 19% higher than the control (56.09 mm and 49.08 mm), respectively, whereas MR and MR + BB-treated trees in Liliw were 34-35% higher relative to control. Soil microbial analysis showed that mycorrhizal spore counts in BB-amended soils were 133% (Liliw), 262% (Magdalena) and 109% (Lipa) higher than the control. Nitrogen-fixing bacteria obtained from MR + BB-amended soils in Liliw were 216% higher than control, and 81% higher relative to control in BB-treated soils in Lipa. Soil nitrogen and potassium contents of the three cacao farms also improved by 26-85%. With the significant effect of bamboo biochar and mycorrhizal fertilizer, alone or in combination, on the growth of cacao, the microbial community and nutrient status of the cacao rhizosphere soil, this technology would be beneficial to cacao farmers and to almost all crops in an agroforest ecosystem.
Biotropia: The Southeast Asian Journal of Tropical Biology, Jun 1, 1995
To examine the effects of soil microbial population on mycorrhizal development and function, Euca... more To examine the effects of soil microbial population on mycorrhizal development and function, Eucalyptus urophylla seedlings were inoculated with two Pisolithus tinctorius isolates and grown in sterile, partly sterile and non-sterile soil. The two isolates of Pisolithus were an effective isolate (H445) collected from under eucalypts in Australia and an isolate (H615) collected from under eucalypts in the Philippines. Soils used were infertile acid soils collected from field sites in Pangasinan, Luzon and Surigao, Mindanao. In both soils, the Australian Pisolithus H445 improved the growth of E. urophylla seedlings more than Philippine isolate H615. The uninoculated seedlings exhibited stunted growth typical of P deficiency. Height at 8 weeks was significantly taller in sterile than in non-sterile soil. A significant interaction effect of inoculation and soil sterilization on height at harvest was observed only in Surigao soil. Soil sterilization had a varied effect on mycorrhizal formation. In Pangasinan soil, root colonization by H445 was significantly greater in non-sterile soil than in sterile soil. Whereas in Surigao soil, root colonization was significantly reduced by 54% from partly sterile to non-sterile soil. On the other hand, H615 showed significant mycorrhizal colonization in non-sterile soil compared from those in partly sterile and sterile soils. The degree of infection did not necessarily correspond to growth promotion in E. urophylla seedlings. These results indicate that the performance of the H445 was markedly affected by the microbial flora of the two soils. Thus, its potential use in the Philippines needs to be thoroughly tested in the field before its widespread use in any inoculation program.
To examine the effects of microbial populations and external phosphorus supply of two Philippine ... more To examine the effects of microbial populations and external phosphorus supply of two Philippine soils on mycorrhizal formation, Eucalyptus urophylla seedlings were inoculated with two Pisolithus isolates and grown in fumigated, reinfested and unfumigated soil fertilized with four rates of phosphorus. The Pisolithus isolates used were collected from under eucalypts in Australia and in the Philippines. Soils were infertile acid silty loams collected from field sites in Pangasinan, Luzon and Surigao, Mindanao. Significant interaction was observed between inoculation, soil fumigation and phosphorus supply on mycorrhizal formation by the Australian isolate in Surigao soil but not in Pangasinan soil. Soil fumigation enhanced mycorrhizal formation by the Australian isolate but did not affect root colonization by the Philippine isolate. Root colonization by the Australian isolate was highest in the reinfested soil while for the Philippine isolate it was highest in the unfumigated soil. The Australian isolate was more effective than the Philippine isolate in promoting growth and P uptake of E. urophylla seedlings in both soils. Total dry weight and P uptake of E. urophylla seedlings inoculated with the Australian isolate were maximum in fumigated and in the reinfested Pangasinan and Surigao soils supplied with 8 mg P kg-1 soil. In the unfumigated soil, growth of seedlings inoculated with the Australian isolate was significantly reduced. Seedlings inoculated with the Philippine isolate had the largest dry weights and P contents in unfumigated Pangasinan and Surigao soils supplied with 8 mg P kg-1 soil. These results indicate that the performance of the Australian Pisolithus isolate was markedly affected by biological factors in unfumigated soil. Thus, its potential use in the Philippines needs to be thoroughly tested in a variety of unfumigated soils before its widespread use in any inoculation programme.
Page 1. Growth response of Acacia mangium Willd. seedlings to arbuscular mycorrhizal fungi and fo... more Page 1. Growth response of Acacia mangium Willd. seedlings to arbuscular mycorrhizal fungi and four isolates of the ectomycorrhizal fungus Pisolithus tinctorius (Pers.) Coker and Couch Nelly Siababa Aggangan Æ Heung Kyu Moon Æ Sim Hee Han ...
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