Utilization of Rhizoplane Bacteria and Arbuscular Fungi Mycorrhizal (AFM) to Improve Growth of Jelutong Seedling (Dyera polyphylla Miq. Steenis.

Nontimber forest products (NTFPs) represent sources of income from tropical forest, but some NTFP species have decreased in population and become endangered due to overexploitation. There is increasing concern that the planting stock of Dyera polyphylla is not sufficient to sustain the yield of NFTPs. The beneficial root colonizing rhizosphere bacteria, the so-called plant growth-promoting rhizobacteria have been known to carry out many important ecosystem processes, such as those involved in the nutrient cycling and/or seedling establishment. The roots of most plant species associate with certain soil fungi and establish what are known as mycorrhiza. The objective of this study was to determine the effect of two arbuscular miycorrhizal (AMF) fungi, Glomus sp., Gigaspora sp. and thirteen strains of hizoplane bacteria (CK32, FL.13.2.1, JW1, JW6, JW9, JW13, JW14, CK26, CK4, JW3a, SB, NT, CR.R1), on the early growth of D. polyphylla, under greenhouse condition. Percentage of AMF colonization, plant growth, and nitrogen (N) and phosphorus (P) concentration were measured after 150 days of planting. The results showed that the percentage of AM colonization of D. polyphylla was 100%. Colonization by Glomus sp. significanly increased plant height by 18,95% and diameter by 16,16% compared to those non AMF. Combination of bacterial and AMF inoculant between JW13 and Glomus sp. increased shoot weight by as much as 36,28% from control and increased N concentration by 69,59% compared to those of non inoculate a seedlings. Combination of JW1 and Gigaspora sp. increased P concentration by as much as 42,05% compared to those of non inoculate seedlings. Despite the difficulty of selecting a multifunctional microbial consortia, appropriate microbial combinations can be recommended for a biotechnological input related to improvement of plant performance.

Mycorrhizal Fungi Increased Early Growth of Tropical Tree Seedlings in Adverse Soil

The rate of reforestation has increased throughout the countries in Southeast Asia region during the last 20 years. At the same time, inconvenient situations such as forest destruction, forest exploitation, illegal logging, clear-cut forest areas, old agricultural lands, post-wildfire areas, conversion of natural forests into plantations, resettlement areas, mine lands, and amended adverse soils have also been increasing significantly. Mycorrhizas, hovewer, play important role to increase plant growth, enrich nutrient content and enhance survival rates of forest tree species in temperate and sub-tropical regions. Unfortunately, a little information so far is available regarding the effect of mycorrhizas on growth of tree species growing in tropical forests. In relevant, several experiments were carried out to determine whether ectomycorrhizal (ECM) fungi and arbuscular mycorrhizal (AM) fungi can enhance mycorrhizal colonization, nutrient content, and plant growth of some tropical rain forest tree species in Indonesia under nursery and field conditions. The families of tropical tree species used in the experiment were Thymelaeaceae (Aquilaria crassna), Leguminosae (Sesbania grandifolia), Guttiferae (Ploiarium alternifolium and Calophyllum hosei), Apocynaceae (Dyera polyphylla and Alstonia scholaris), and Dipterocarpaceae (Shorea belangeran). These families are important as they provide timber and non-timber forest products (NTFPs). This paper discusses the role of mycorrhizal fungi in increasing early growth of tropical tree seedlings in adverse soil

Studies on Functional Bacteria of Indonesian Tropical Forest Plants for Biorehabilitation of Degraded Lands

Forest degradations have left vast amount of damaged and abandoned lands in Indonesia. In this paper, we present our approaches in rehabilitation of adverse soils using functional bacteria isolated from plant species of Indonesian tropical rain forests. For these purposes, we collected bacteria from various bio-geo-climatically different forests and conducted bioassays to test these bacterial abilities in improving plant growth. Repeated seedling-based studies on Shorea spp., Alstonia scholaris, Acacia crassicarpa, and Agathis lorantifolia have revealed that many bacteria were able to promote plant growth at early stage in the nursery. Various plant responses towards inoculations suggested that although forest soils maintain highly diverse and potent bacteria, it is necessary to select appropriate approaches to obtain optimum benefits from these plant-bacteria interactions. Our ideas and futures studies for further management of these plant- bacteria interactions for biorehabilitation are also discussed

Anti Fungal Activity of Wood Extract of Aquilaria Crassna Pierre Ex Lecomte Against Agarwood-inducing Fungi, Fusarium Solani

This paper provided information regarding artificial agar wood production. Fungi are considered as biological agent for agarwood formation and agarwood is assumed as tree defense mechanism product. This research was aimed at investigating the anti fungal activity (AFA) of Aquilaria crassna, one of the agar wood-producing trees, against Fusarium solani in vitro. Aquilaria crassna wood mill was extracted by 70% ethanol to investigate the anti fungal activity. The result are Aquilariacrassnaexhibited low extractives content, which was only 2.0% (w/w) and a low anti fungal activity in vitro, especially for ethanol extract. However, further fractionation and bioassay showed that the most active component was likely in the ethyl-acetate soluble fraction that exhibited strong anti fungal activity (52.5%) at 4.0% of concentration

Salkowski’s Reagent Test as a Primary Screening Index for Functionalities of Rhizobacteria Isolated from Wild Dipterocarp Saplings Growing Naturally on Medium-Strongly Acidic Tropical Peat Soil

Rhizobacteria isolated from wild dipterocarp saplings in Central Kalimantan, Indonesia, were subjected to Salkowski’s reagent test, which is often used in detecting indolic substances. Among 69 isolates grown in a low-nitrogen medium supplemented with L-tryptophan (TRP), culture fluids of 29 strains were positive to the test, in which 17 bacteria turned red and other 10 pink. All the red type rhizobacteria actively converted TRP into tryptophol (TOL), while some yielded indole-3-acetic acid (IAA) with TOL production. They also showed a capacity to decompose gallotannin into pyrogallol via gallic acid. On the other hand, an active IAA-producing Serratia sp. CK67, and three Fe-solubilizing Burkholderia spp. CK28, CK43, and Citrobacter sp. CK42, were all involved in pink type rhizobacteria, which were more effective, oxidative TRP-degraders than the red type rhizobacteria. Thus, Salkowski’s reagent test should be a useful primary index in the screening of functional rhizobacteria in peatland ecosystem

GROWTH-PROMOTING PROPERTIES OF BACTERIA ISOLATED FROM RHIZOSPHERE AND RHIZOPLANE OF DIPTEROCARP PLANTS ON ACIDIC LOWLAND TROPICAL PEAT FOREST IN CENTRAL KALIMANTAN, INDONESIA

Dipterocarpaceae is a group of native, predominant trees of Indonesia lowland tropical forest. It is now under a serious threat of extinction due to continual forest degradations. Although dipterocarps have been used for reforestation, in the case of peat forests, transplanted seedlings typically suffer low survivar rates due to acidie soil, low nutrient content, and the presence of toxic elements. To produce robust seedlings, many studies have suggested an inclusion of plant growth-promoting rhizobacteri (PGPR). However little or no studies have been done to PGPR of dipterocarps. This study is a part of our wider effort to search for potential PGPR for bio-reforestation in degraded lands in Indonesia. We characterized PGPR of dipterocarps for their capacities to solubilize P, fix N,. and/or help ectomycorrhization in vitro. Bacteria were isolated from shorea terysmanniana,S. parviflora,S. belangeran,S. stenoptera, Dipterocarpus dp., amd Hopea sp. of acidic,lowland peat swamp forest in Central Kalimantan. A total of 71 bacterial strains from rhizoplane and rhizosphere were isolated in an N-free Winogradsky's soft gel medium. While most bacteria possessed PGPR traits in vitro, 14 showed the best PGPR efficiency. The best P solubilizers were Erwinia spp. CK23,CK24 and CK10, Roseateles sp. CK15, Rhizobium sp. CK19, Burkholderia sp. CK52,NI CK42,NI CK53,and NI CK54. The heighest N2 fixers were Azospirillum sp. CK26, Burkholderia sp. CK32, and NI CK4. A Choromobacterium sp. CK8 was the most potential ectomycorrhization helper of Laccaria sp. We demonstrated that Dipterocarpaceae harbored diverse bacterial genera and potential PGPR candidates which may be utilized as growth promoters for preparation of robust seedlings for bio-reforestation of degraded lands

Production of high protein yeast using enzymatically liquefied almond hulls.

Animal feed ingredients, especially those abundant in high quality protein, are the most expensive component of livestock production. Sustainable alternative feedstocks may be sourced from abundant, low value agricultural byproducts. California almond production generates nearly 3 Mtons of biomass per year with about 50% in the form of hulls. Almond hulls are a low-value byproduct currently used primarily for animal feed for dairy cattle. However, the protein and essential amino acid content are low, at ~30% d.b.. The purpose of this study was to improve the protein content and quality using yeast. To achieve this, the almond hulls were liquefied to liberate soluble and structural sugars. A multi-phase screening approach was used to identify yeasts that can consume a large proportion of the sugars in almond hulls while accumulating high concentrations of amino acids essential for livestock feed. Compositional analysis showed that almond hulls are rich in polygalacturonic acid (pectin) and soluble sucrose. A pectinase-assisted process was optimized to liquefy and release soluble sugars from almond hulls. The resulting almond hull slurry containing solubilized sugars was subsequently used to grow high-protein yeasts that could consume nutrients in almond hulls while accumulating high concentrations of high-quality protein rich in essential amino acids needed for livestock feed, yielding a process that would produce 72 mg protein/g almond hull. Further work is needed to achieve conversion of galacturonic acid to yeast cell biomass