BIOTROPIA - The Southeast Asian Journal of Tropical Biology
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SITE INDEX OF SIAMESE ROSEWOOD (Dalbergia cochinchinensis Pierre) IN PLANTATIONS OF THAILAND
Get PDFCurrently, decreased productivity of Siamese rosewood (Dalbergia cochinchinensis Pierre) is a problem due to illegal logging and the guidelines to manage this prevention may be insufficient. Forest plantations should be promoted to achieve sustainable wood production for this species. Site index (SI) is a measure that can be used to predict forest productivity to identify appropriate sites for planting Siamese rosewood. The objective of the current study was to predict the SI for Siamese rosewood in Thailand. A sample of 78 temporary plots at 26 sites in 16 provinces of Thailand was selected to construct a site index curve with a base age of 30 years. The results showed that the mean age of Siamese rosewood was 28 years (between 13 and 55 years), the mean diameter at breast height (DBH) was 20.03 cm (between 7.99 and 33.80 cm), and the mean dominant height was 20.79 m (between 7.32 and 24.82 m). The SI equation was: SI = 0.406 at p < 0.0001 (chosen as 30 years in the present study). The equation indicated that 14, 18, 22, 26, and 30 m trees belonged to site classes I, II, III, IV, and V, respectively. Although in natural forests Siamese rosewood is distributed in dry evergreen and mixed deciduous forests, in the present study, several sites in areas under both in situ and ex situ conservation were in the good and very good site categories. Thus, both areas can be used to plant Siamese rosewood and increase its productivity
THE RANGE EXPANSION OF Parachromis managuensis (GÜNTHER, 1867) (PERCIFORMES, 4 CICHLIDAE) IN JAVA, INDONESIA
Get PDFThe Jaguar cichlid, Parachromis managuensis (Günther, 1867), is native to Central America, with introductions reported from West Java and Central Java Provinces of Indonesia. On 7-8 January 2019, sixteen specimens of P. managuensis were collected from Karangkates, the largest hydropower reservoir in East Java Province of Indonesia. A description of the morphological characters of specimens is provided
LIMITED SEED DISPERSAL MAY SHAPE GENETIC STRUCTURE OF Hydnophytum formicarum Jack. POPULATIONS IN MANGROVE ECOSYSTEM
Get PDFHydnophytum formicarum is an epiphytic plant commonly distributed throughout Southeast Asia. However, its distribution is currently declining due to forest fragmentation and the subsequent habitat changes, which may have also affected the genetic structure of H. formicarum populations. Hence, this study aimed to understand the genetic variation and differentiation within and among populations of this species. Using Random Amplified Polymorphic DNA (RAPD) markers, the genetic variation and genetic differentiation among three populations were assessed to identify potential conservation management strategies for this species in the mangrove ecosystem in Malaysia. Ten highly reproducible primers were used in the population analysis, resulting in a total of 221 discernible fragments. Genetic variation among populations was high at 98% polymorphic fragments. AMOVA showed significant genetic differentiation among the populations (PT = 0.554, p ≤ 0.001), with pairwise genetic distances between the populations ranging from 0.495 to 0.589. PCoA clustering analysis separated the populations according to their geographical locations. The high genetic variation within populations, high genetic differentiation between populations, and clear separation in the cluster analysis indicate restricted seed dispersal of the species
CHARACTERIZATION OF RHIZOBACTERIA ISOLATES FROM SOIL AND NODULES
No full textThe plant growth promoting rhizobacteria (PGPR) is a group of bacteria capable of colonizing plants roots, thereby developing a system and improving plants growth and yield. The objectives of the study is to characterize the PGPR activities of several bacterial isolates {in-vitro screening), to examine their activities in stimulating soybean growth (in-vivo screening), and to identify the bacterial species. These were isolated from nodules and soil samples collected from Mount Pancar in Bogor, West Java Province as well as from Bangkirai Hill and Wain River in East Kalimantan, Indonesia. The in-vitro PGPR activity characterization includes the N-fixing ability, ACC-deaminase, indole acetic acid (IAA) production, cellulolytic activity, P-solubilization, Phosphomonoesterase (PME-ase), and nifH-gene detection. The in-vivo PGPR activity with the greenhouse assay was conducted on soybean plant {Glycine max L.). All bacterial isolates were identified using molecular methods based on nucleotide sequence generated from 16S rRNA gene. Three isolates of soil and nodule bacteria with 7 characteristics of PGPR (N2 fixation, ACC-deaminase, cellulolytic activity, IAA production, solubilization index, P available, and PMEase activity) were successfully identified. These isolates were B045 {Klebsiella variicola InaCC B827), B116 (Klebsiella sp. InaCC B833), and B210 {Mangrovibacterplantisponsorlaa.CC B841). The greenhouse assay showed that the plant height, plant dry weight and number of flowers in soybean seedlings significantly increased with Bradyrhispbium sp. strain 4167, then with Klebsiella sp. InaCC B833 and Mangrovibacterplantisponsor InaCC B841. These bacterial isolates which were characterized and screened in-vitro for PGPR potentials and their representative isolates which were identified by 16S rRNA sequence analysis are key factors for selecting PGPR isolates to be commercialized later as bio-stimulant
EVALUATION OF REVEGETATION PRACTICES IN POST-MINED AREAS OF INDONESIA
Get PDFIn compliance with government regulations, mining companies in Indonesia are obliged to reclaim and return post-mined areas to their pre-mining condition. Revegetation, as part of reclamation activities, plays a significant role in the rehabilitation of degraded post-mined areas to restore their productive land uses. Hence, this study aimed to assess tree growth on reclamation sites across four mining companies in East Kalimantan, South Sulawesi, South Sumatra, and West Java in Indonesia, and to evaluate whether the companies have met the legal requirements set for site revegetation. The success parameters were based on the applicable regulations of the Ministry of Environment and Forestry (MOEF) P.60/Menhut-II/2009 and tree growth parameters (stem diameter, total height, and basal area). The parameters set by MOEF included revegetation realization, survival rate, tree density, tree health, species composition, and rotation length. The four mining companies applied the two-phase planting method that included the planting of Enterolobium cyclocarpum for the first phase; and in the second phase, the slow-growing native species such as Intsia palembanica, Syzygium polyanthum, Shorea spp., and Elmerillia tsiampaca. The tree growth parameters showed different performances across species and reclaimed sites. An extremely high growth of stem basal area—57.6 m²/ha in 11 years—was recorded in the E. cyclocarpum stand of the mining company in South Sulawesi. All four mining companies strived to comply with the regulation, with scores of revegetation success ranging from 15 to 25 out of 25 possible points. However, these favorable results may not be representative of all mining companies, as those assessed were only companies voluntarily supporting this research. Moreover, each of the four companies made distinct efforts in implementing post-mining revegetation, such as establishing plots of Melaleuca cajuputi producing cajuput oil and polycultures of native species
GROWTH PERFORMANCE OF DIPTEROCARP SPECIES PLANTED ON ABANDONED MINING AREA IN SOUTHERN THAILAND
Get PDFDominant Dipterocarp trees hold a significant importance in the ecology and economics of the declining tropical forests of Asia. Of equal importance is the restoration of these Dipterocarp forest using the technique of matching species with silvicultural practices. The study aimed to investigate the effect of the Acacia mangium nurse trees on the survival and growth of six Dipterocarp species planted on abandoned mining areas in the Phangnga Forestry Research Station, Thailand, namely; Dipterocarpus alatus Roxb., Dipterocarpus gracilis Blume, Hopea odorata Roxb., Shorea gratissima (Wall. ex Kurz) Dyer, Shorea roxburghii G. Don, and Parashorea stellata Kurz. The approximately 1.5-year-old Dipterocarp seedlings were planted at a 6-year-old A. mangium plantation cover and at open plots. The survival rate, diameter at root collar (D0), total height (H) and the relative growth rate (RGR) of D0 and H of the seedlings were compared. Soil samples at the open and the A. mangium plots were collected and its physical and chemical properties were analyzed. The results indicated that the survival rates of the Dipterocarps planted at the A. mangium plot were higher than those at the open plots. The survival rates (75-100%) of the 1 to 3-year-old D. alatus, H. odorata, S. gratissima, S. roxburghii, and P. stellata were relatively high at the A. mangium plot, but not for D. gracilis. The D0 of S. roxburghii, D. alatus, H. odorata, and P. stellata were higher at the A. mangium plot. However, the D0 and H of S. roxburghii, D. alatus, and H. odorata at the open plot were high and similar to that of the A. mangium plot. RGRD0 and RGRH of S. roxburghii, D. alatus, and H. odorata were high both at the A. mangium and the open plots. Generally, the Dipterocarp seedlings were growing better under the A. mangium nurse trees, thus suggesting the possibility of their improved survival and growth in mined out areas. Moreover, the findings also suggest that S. roxburghii, D. alatus, and H. odorata can be planted at open areas with poor soil conditions and extreme environments. Lastly, thinning interventions are also needed to improve the growth of Dipterocarp trees
GROWTH, PHOTOSYNTHESIS AND PROLINE ACCUMULATION OF METAL-ACCUMULATOR WEEDS
Get PDFIntensive use of heavy metals, particularly lead and mercury, in industrial activities and mining extraction has caused the widespread distribution of these contaminants, thereby threatening the environment. Consequently, the growth and several physiological responses of five metal-accumulator weed species were examined in response to mercury (Hg) and lead (Pb) treatments. The weed species Brachiaria mutica, Cyperus kyllingia, Ipomoea aquatica, Mikania micrantha, and Paspalum conjugatum were grown in water culture using half-strength Hoagland\u27s solution and subjected to Hg(NO₃)₂ and Pb(NO₃)₂ at concentrations of 0, 0.25, and 0.5 mM for 3 weeks. Plant growth, photosynthesis, lipid peroxidation, and proline content were observed. Both Hg and Pb significantly reduced plant growth, but the decrease was more pronounced under Hg treatment than under Pb. Hg dramatically reduced the photosynthetic rate under different photosynthetic photon flux densities, indicating that Hg up to 0.5 mM damaged the photosynthetic apparatus in almost all species except I. aquatica. Hg and Pb treatments caused a dramatic increase in leaf MDA content, which was associated with a significant decrease in chlorophyll content. Most species were tolerant to Pb up to 0.5 mM except M. micrantha, while only C. kyllingia and I. aquatica were tolerant to Hg treatment up to 0.5 mM. Hg treatment also induced higher proline accumulation in leaves, although without a clear increment pattern among species, suggesting that proline may function as a stress alarm rather than as a tolerance indicator
DIVERSITY AND VERTICAL DISTRIBUTION OF VASCULAR EPIPHYTES ON A MALAYSIAN MANGROVE ISLAND
Get PDFMany studies have attempted to explain the diversity and abundance of epiphytic plants in major ecosystems worldwide. However, investigations on the abundance of epiphytic plants in mangroves have remained rare. The aim of this research was to study the diversity and vertical distribution of vascular epiphytes in a mangrove forest in Peninsular Malaysia. Sampling was conducted over a 0.1-hectare plot on Pulau Telaga Tujuh, a mangrove island in Terengganu, Malaysia. Trees with vascular epiphytes were divided into three strata: basal, trunk, and canopy. The vascular epiphytes were identified, and the number of individuals in each stratum was recorded. In total, eight species of vascular epiphytes from six genera and four families were recorded. Pulau Telaga Tujuh mangrove forest exhibited a relatively low diversity of vascular epiphytes (H\u27 = 1.43). The dominance of Hydnophytum formicarium significantly contributed to the diversity of vascular epiphytes in this forest. The highest abundance of epiphytes was observed on the trunks of the host trees. The vertical distribution pattern observed in this study is associated with the adaptation of epiphytic plants to stresses in the mangrove ecosystem, particularly drought and salt spray. Pulau Telaga Tujuh had a high density of vascular epiphytes but lower diversity compared with other ecosystems
ANTIFUNGAL Citrus hystrix EXTRACT AS NATURAL FOOD PRESERVATIVE
Get PDFDuring their storage, the traditional ready-to-eat food, such as sticky rice cake, is easily contaminated by spoilage pathogens. Hence, this study aims to evaluate the effect of Citrus hystrix extract in reducing spoilage pathogens in sticky rice cake during storage. The experimental sticky rice cake was prepared and formulated with Citrus hystrix extract at varied concentrations of 0.65%, 1.26%, and 1.82% (w/w). Treated samples were stored at room temperature for 28 days and evaluated periodically for their microbial activity (total plate count), thiobarbituric acid reactive substances (TBARS), and sensory analysis. For its antifungal activity, the Citrus hystrix extract was also compared against Penicillium sp. and Aspergillus nidulans prior to formulation. Results exhibited a significant advantage of the added extracts to the sticky rice cake. All extract levels effectively eliminated the spoilage microorganisms and significantly lowered the TBARS values. The physico-chemical properties of sticky rice cake including pH, water activity, and moisture content were equal among all the formulated samples and slightly different at 1.82% (w/w) extract level. Moreover, the addition of Citrus hystrix extract up to 1.82% did not affect the acceptability sensory attributes of the sticky rice cake as compared to the control which had no Citrus hystrix extract (p > 0.05)
EFFECT OF POWDER AND LIQUID PREPARATIONS OF PROBIOTICS ON WHITE SHRIMP (Litopenaeus vannamei) GROWTH PERFORMANCE
Get PDFIndonesia is the second largest supplier of white shrimp (Litopenaeus vannamei, Boone 1931) in the USA market. Hence, the need for its sustainable production and improved growth. Probiotics, among others, are known for their growth enhancing attributes. Therefore, this study was conducted to determine the effects of powder and liquid probiotics on the growth of white shrimps at the Minaloka Jaya shrimp ponds, Grabag District, Purwerojo Regency, Central Java. The shrimps were cultivated for 60 days and applied with three probiotic treatments, namely commercial liquid probiotics with dosage of 10 mL/kg feed, powder probiotics with dosage of 10 g/kg feed and liquid probiotic with dosage of 10 mL/kg feed. Each probiotic preparation was administered four times a day to over 150,000 vannamei shrimps which were cultured in a semi-intensive system. Probiotics in powder and liquid forms contain Lactobacillus fermentum, L acidophilus, L. plantarum, L, curvatus, Bacillus licheniformis, B. subtilis, and B. polimyxa. B. megaterium, B. coagulans, Pseudomonasputida, Nitrosomonas sp. and Nitrobacter sp. Using the Randomized Block Design (RBD), the three treatments were replicated five times. The application of probiotics in both powder and liquid forms had increased the growth yield of the vannamei shrimp. However, the powder probiotic had shown better growth performance than the commercial liquid probiotics and liquid preparation of probiotics. Probiotic powder form provides a specific growth rate (SGR) of 8.18%, absolute body length of 9.68 cm, absolute biomass of 6.78 g, and feed conversion ratio (FCR) of 1.93