bluuebunny/crossref_metadata_2025 huggingface dataset:
Diversity, biomass, and carbon stock of understorey plants in the rubber agroforestry and rubber monoculture systems in Central Tapanuli District, North Sumatra, Indonesia
Authors: Muhdi Muhdi , HANAFIAH DIANA SOFIA , BUTAR-BUTAR RITA DESPRIANA
Published: August 2020

Abstract. Muhdi, Hanafiah DS, Butar-Butar RD. 2020. Diversity, biomass, and carbon stock of understorey plants in the rubber agroforestry and rubber monoculture systems in Central Tapanuli District, North Sumatra, Indonesia. Biodiversitas 21: 3508-3518. Understorey vegetation plays an important role in carbon stock in forest. The objectives of the research were to identify the species of understorey, to find out the amount of carbon stored in the understorey, and to compare the understorey carbon stocks in rubber agroforestry and rubber monoculture. The research was done in Sijungkang Village, Andam Dewi Sub-district, District of Central Tapanuli and Forest Products Chemistry Laboratory, Faculty of Forestry, IPB University on August-October 2016. The method used was the plant vegetation analysis of a stand and understorey. Destructive sampling method was used to harvest of understorey plant in 1 m × 1 m sample plot. The carbon of understorey was analyzed by independent sample t-test. The results showed that there were 23 species in rubber agroforestry and 15 species in rubber monoculture. The understorey species dominant of rubber agroforestry was Stachytarpheta jamaicensis and rubber monoculture was Asystasia gangetica with important value index 30.64% and 33.01%, respectively. The average understorey plant biomass in rubber monoculture was 0.94 tons/ha and in rubber agroforestry were 0.84 tons/ha, respectively. The carbon stocks of understorey in rubber agroforestry were 0.21 tons/ha and in rubber monoculture were 0.25 tons/ha, respectively. The result of t-test showed that there is not significant difference between carbon stock of understorey in rubber agroforestry and rubber monoculture.
Ex-situ conservation of Cymbidium finlaysonianum by seed storage
Authors: PUSPITANINGTYAS DWI MURTI , HANDINI ELIZABETH
Published: August 2020

Abstract. Puspitaningtyas DM, Handini E. 2020. Ex-situ conservation of Cymbidium finlaysonianum by seed storage. Biodiversitas 21: 3519-3524. Cymbidium finlaysonianum Lindl. is an orchid that is native to Indonesia which has a pendulous flowers and relatively attractive colors. As a part of the Orchid Seed Storage for Sustainable Use (OSSSU) project, a preliminary study on seed of Cymbidium finlaysonianum Lindl. was conducted to test its viability at Bogor Botanic Gardens, Indonesian Institute of Sciences. The aim of this research was to evaluate the seed viability and to predict the seed longevity of C. finlaysonianum, after storage for different periods at freezing temperature-20°C. Storing of orchid seeds under cold conditions was the best conventional method in prolonging seed viability. Four different culture media were tested for asymbiotic germination. Seed viability was assessed after the seeds were stored for 0, 1, 2, 3, 6, 9, 12 months. Testing continued every year until there was no seed germination, and the viability was lost. The direct method of counting the number of germinating seeds was used to test seed viability. The result showed that seeds of C. finlaysonianum were able to germinate in 4 media i.e. Knudson C, modified Knudson C, modified Vacin & Went, and modified Hyponex fertilizer. The research showed that the viability seeds of C. finlaysonianum decreased after 2 years of storage, and the seeds were almost completely non-viable after six years of storage.
Genetic diversity in Eddoe Taro (Colocasia esculenta var. antiquorum) from Indonesia based on morphological and nutritional characteristics
Authors: Maretta Delvi , Sobir Sobir , Helianti Is , Purwono Purwono , Santosa Edi
Published: August 2020

Abstract. Maretta D, Sobir Helianti I, Purwono, Santosa E. 2020. Genetic diversity in Eddoe Taro (Colocasia esculenta var antiquorum) from Indonesia based on morphological and nutritional characteristics. Biodiversitas 21: 3525-3533. Low yield uniformity and quality due to genetic performance become negative incentives to farmers in Eddoe Taro production. However, genetic evaluation is rarely been reported in this taro type in Indonesia. In this study, 14 eddoe genotypes collected from different regions in Indonesia were evaluated to develop a diversity map for crop improvement and future breeding activities. The genotypes were planted in the open field from September 2018 to March 2019 at the experimental station belonging to LAPTIAB-BPPT, PUSPITEK at South Tangerang District, Indonesia. Morphological and nutritional characters were accessed on the shoot and underground parts. The genotypes exhibited variation in 38 out of 48 characters in which 12 quantitative characters were distinct including oxalate level. The study revealed three findings: (i) Characters related to growth and yield had high genotypic variance coefficients, i.e., sheath length, total petiole length, plant height, number of suckers, corm and cormels weight, (ii) Genotypes clustered into two separate groups as introduced and landraces, and (iii) Landraces had high genetic variation leading to speculation of high clonal variation. Considering the findings, accession S6, S7, S18, S30, and S36 are recommended for further studies in crop improvement purposes.
Genetic diversity and selection within natural dura oil palm accessions collected in Ghana for oil palm productivity improvement
Authors: Osei Darkwah Dickson , Blay Essie , Amoatey Harry , Sapey Enoch , Bakoume Claude , Agyei-Dwarko Daniel
Published: August 2020

Abstract. Darkwah DO, Blay E, Amoatey H, Sapey E, Bakoume C, Agyei-Dwarko D. 2020. Genetic diversity and selection within natural dura oil palm accessions collected in Ghana for oil palm productivity improvement. Biodiversitas 21: 3534-3538. The genetic base of oil palm breeding stock of the Ghanaian Oil Palm Research Institute is considered narrow after two selection cycles. Therefore, 79 accessions of natural dura oil palm collected in Ghana and conserved at Oil Palm Research Institute (OPRI) were field evaluated for 18 agro-morphological traits. ANOVA revealed differences among the 79 dura oil palm accessions for 14 traits. The most heritable traits were single fruit weight (h2 = 0.85), leaf area index (h2 = 0.63), bunch weight (h2 = 0.52), total leaf area (h2 = 0.51), and fresh fruit bunch (h2 = 0.46). Genetic coefficients of variation ranged from 3.30% for frond dry weight to 68.74% for total bunch weight denoting possibility of selection of desirable traits for improvement. Five high fresh fruit bunch yielding accessions (FFB ≥ 10.81 t/ha) with good heritable bunch characteristics were selected for introduction in the breeding stocks. In fact, their bunch number, average bunch weight, and mesocarp to fruit were higher, in absolute terms, than the controls and trial mean obtained in the study. Although, the height increment was close to those of the controls, short progenies are expected among descendants from their selfings or crosses.
Some botanical aspects of Etlingera flexuosa (Zingiberaceae) from Central Sulawesi (Indonesia) and its antifungal activity
Authors: Pitopang Ramadanil , Umrah Umrah , Harso Wahyu , Nurainas Nurainas , Zubair Muhammad Sulaiman
Published: August 2020

Abstract. Pitopang R, Umrah, Harso W, Nurainas, Zubair MS. 2020. Some botanical aspects and antifungal activity of Etlingera flexuosa (Zingiberaceae) from Central Sulawesi, Indonesia. Biodiversitas 21: 3547-3553. Etlingera flexuosa is a species of Etlingera endemic to the island of Sulawesi and its natural distribution is restricted to Central and South Sulawesi, where it has been utilized for different purposes. Despite the limited knowledge in the aspects of botany and its antimicrobial activities, the use of plants as a source of alternative solutions to health problems is on the rise. The objectives of this study were to obtain some information about the several botanical aspects of E. flexuosa and its antifungal activity. This research was conducted from March to December 2019 and samples were collected from the montane forest of Lore Lindu National Park (LLNP) near Sedoa Village, Lore Utara Sub-district, Poso District, Indonesia. The identification of plant specimens and extractions was carried out at the Laboratory of Plant Biosystematics, Tadulako University, Palu, Indonesia. The antifungal activity was tested using agar diffusion methods. The results showed that E. flexuosa is a perennial herb naturally distributed in Sulawesi island. It usually grows in the pristine submontane and montane forests, sometimes in light and open condition or on the slope of natural disturbed forest at the altitude of 1500 -1700 m a.s.l. The forest is dominated by Fagaceae family, of which E. flexuosa has been utilized extensively by local community of Topo Baria ethnic for various purposes such as flavor enhancer in food, vegetable, traditional medicine, and as roofing materials. It contains some secondary metabolites such as flavonoids, tannins, saponins, terpenoids, alkaloids and steroids, and also shows antioxidant activity. Conclusively, the extract of E. flexuosa could be used as inhibiting agent for the growth of Candida albicans yeast.
Short Communication: Molecular barcode and morphology analysis of Malva pseudolavatera Webb & Berthel and Malva sylvestris L. from Ecuador
Authors: SARMIENTO-TOMALÁ GLENDA , Santos-Ordóñez Efrén , MIRANDA-MARTÍNEZ MIGDALIA , PACHECO-COELLO RICARDO , SCULL-LIZAMA RAMÓN , GUTIÉRREZ-GAITÉN YAMILET , RENÉ DELGADO-HERNÁNDEZ RENÉ
Published: August 2020

Abstract. Sarmiento-Tomalá G, Santos-Ordóñez E, Miranda-Martínez M, Pacheco-Coello R, Scull-Lizama R, Gutiérrez-Gaitén Y, Delgado-Hernández R. 2020. Short Communication: Molecular barcode and morphology analysis of Malva pseudolavatera Webb & Berthel and Malva sylvestris L from Ecuador. Biodiversitas 21: 3554-3560. In Ecuador, several plant species are used in traditional medicine without a criterion of family, genera, or chemical composition. The species of the genus Malva (Malva pseudolavatera Webb & Berthel and Malva sylvestris L), introduced in Ecuador, are widely used by the population; however, unlike the species M. sylvestris, for M. pseudolavatera there is no information about its composition and properties. Plant material was collected in the province of Chimborazo in Ecuador and taxonomic classification was performed. Histological study was performed in leaves and powder drug. Molecular barcodes were generated using the ribulose bisphosphate carboxylase large chain (rbcL), maturase K (matK), internal transcribed spacer 1 (ITS1) and ITS2 sequences. Micro-morphological analysis revealed that no major structural differences were observed between the two species. Sequence analysis of molecular barcodes revealed that samples of the different species showed a close relation to each other due to the high percentage of similarity. The ITS sequences showed that the two samples correspond to different species of Malva; while for the rbcL and matK, interspecies differentiation could not be detected. Therefore, ITS could be used for interspecific analysis.
Multivariate analysis to determine secondary characters in selecting adaptive hybrid corn lines under drought stress
Authors: FADHLI NUR , FARID MUH. , RAFIUDDIN  , EFFENDI ROY , AZRAI MUHAMMAD , ANSHORI MUHAMMAD FUAD
Published: August 2020

Abstract. Fadhli N, Farid M, Rafiuddin, Efendi R, Azrai M, Anshori MF. 2020. Multivariate analysis to determine secondary characters in selecting adaptive hybrid corn lines under drought stress. Biodiversitas 21: 3617-3624. The development of adaptive hybrid corn varieties under drought stress needs an effective selection. Multivariate analysis has been reported can increase the effectiveness of selection in plants by attaching the secondary characters in the selection. Therefore, this concept also can be applied to develop adaptive corn varieties under drought stress. The objectives of this study are to determine the main secondary characters and select the best hybrid lines adaptive to drought stress. The experiment was arranged by a nested design, where replications nested under two environmental conditions, namely normal and drought stress. The main factor was genotypes consisted of 30 genotypes and was repeated three times. Moreover, the observations of this research consisted of 20 variables. The result of this research showed that the weight of harvested cob was an effective secondary character as a selection criterion along with productivity in selecting adaptive maize genotypes under drought stress. The number of green leaves was the character outside of the yield component could be as an alternative secondary character besides the weight of harvested cob. The selection results based on the weight of the harvested cob and productivity resulted in 12 hybrid corn lines considered adaptive to drought stress.
Increasing accuracy: The advantage of using open access species occurrence database in the Red List assessment
Authors: Robiansyah Iyan , Wardani Wita
Published: August 2020

Abstract. Robiansyah I, Wardani W. 2020. Increasing accuracy: The advantage of using open access species occurrence database in the Red List assessment. Biodiversitas 21: 3658-3664. IUCN Red List is the most widely used instrument to assess and advise the extinction risk of a species. One of the criteria used in IUCN Red List is geographical range of the species assessed (criterion B) in the form of extent of occurrence (EOO) and/or area of occupancy (AOO). While this criterion is presumed to be the easiest to be completed as it is based mainly on species occurrence data, there are some assessments that failed to maximize freely available databases. Here, we reassessed the conservation status of Cibotium arachnoideum, a tree fern distributed in Sumatra and Borneo. This species was previously assessed by Praptosuwiryo (2020, Biodiversitas 21 (4): 1379-1384) which classified the species as Endangered (EN) under criteria B2ab(i,ii,iii); C2a(ii). Using additional data from herbarium specimens recorded in the Global Biodiversity Information Facility (GBIF) website and from peer-reviewed scientific papers, in the present paper we show that C. arachnoideum has a larger extent of occurrence (EOO) and area of occupancy (AOO), more locations and different conservation status compared to those in Praptosuwiryo (2020). Our results are supported by the predicted suitable habitat map of C. arachnoideum produced by MaxEnt modelling method. Based on our assessment, we propose the category of Vulnerable (VU) C2a(i) as the global conservation status for C. arachnoideum. Our study implies the advantage of using open access databases to increase the accuracy of extinction risk assessment under the IUCN Red List criteria in regions like Indonesia, where adequate taxonomical information is not always readily available.
Short Communication: Effectiveness of nuclear gene in species and subspecies determination of captive orangutans
Authors: ABDUL-MANAN MUHAMMAD NURISMADEE , ABD RAHMAN MOHD-RIDWAN , RAHMAN NOR AIFAT , OSMAN NUR AZIMAH , ABU BAKAR MUHAMMAD  ABDUL-LATIFF , DHARMALINGAM SABAPATHY , MD ZAIN BADRUL MUNIR
Published: August 2020

Abstract. Abdul-Manan MN, Mohd-Ridwan AR, Aifat NR, Osman NA, Abdul-Latiff MA, Dharmalingam S, Md-Zain BM. 2020. Short Communication: Effectiveness of nuclear gene in species and subspecies determination of captive orangutans. Biodiversitas 21: 3665-3669. Genetic identification of captive orangutans is of paramount importance in providing a correct identity that is essential for captive management. Thus, the utility of nuclear DNA sequences was tested in this study to identify the genetic identity of captive orangutans at Bukit Merah Orang Utan Island. Out of 24 DNA samples that were successfully extracted, only 10 orangutan samples were successfully sequenced for the von Willebrand factor (vWF) gene. From the results, this gene was able to separate the genus Pongo at the species level. Distance and character analyses indicated that a clear separation between P. pygmaeus and P. abelii at the species level. However, the degree of separation at species level was indicated in tree topology with moderate bootstrap values. At the subspecies level of P. pygmaeus, this gene was unable to show a clear separation between three Bornean subspecies. All the subspecies were formed clade together with each other. The vMF gene is a good nuclear gene for the study of phylogenetic relationships of orangutans in captivity at the species level, but the genetic identification at subspecies level in the genus level remains unclear. We suggest that future studies should involve multiple independent nuclear markers to increase the probability of getting reliable results.
Short Communication: The fruit plant species diversity in the home gardens and their contribution to the livelihood of communities in rural area
Authors: ELFRIDA Elfrida , Mubarak Albian , Suwardi Adi Bejo
Published: August 2020

Abstract. Elfrida, Mubarak A, Suwardi AB. 2020. Short Communication: The fruit plant species diversity in the home gardens and their contribution to the livelihood of rural communities in Tenggulun Sub-district, Aceh Tamiang, Indonesia. Biodiversitas 21: 3670-3675. Home gardens have a significant potential to improve food security and offer a contribution to household income for communities in rural areas. The aim of this study was to assess the diversity of fruit plant species in the home gardens and their contribution to the livelihood of rural communities in Tenggulun Sub-district, Indonesia. The study was conducted in three villages of Tenggulun Sub-district, Aceh Tamiang District, namely Tenggulun, Selamat, and Simpang Kiri. Extensive field surveys, plant collections, and interviews with local communities were conducted, involving 350 households, using random sampling methods. A total of 39 fruit plant species consisting of 23 genera and 17 families were recorded at the three villages. Sixteen species, i.e., A. muricata, A. jiringa, Artocarpus integer, Averrhoa bilimbi, Baccaurea motleyana, Carica papaya, Citrus aurantifolia, Citrus hystrix, Garcinia mangostana, Mangifera indica, Manilkara zapota, Musa x paradisiaca, Nephelium lappaceum, Psidium guajava, Spondias pinnata, and Syzygium aqueum were the most frequently recorded in all of the villages. In addition to being used as food, the fruit plants in the study area were also used as medicines, fodder, fuelwood, and household items. The fruit plant species have a significant role in supporting household livelihoods to improve food security and potentially offer a household income for the rural community in the study area.
Soil characteristics and CO2 emissions of ex-burnt peatland in Kubu Raya District, West Kalimantan, Indonesia
Authors: Astiani Dwi , TRI WIDIASTUTI  , SITI LATIFAH  , SIMATUPANG DARBIN
Published: August 2020

Abstract. Astiani D, Widiastuti T, Latifah S, Simatupang D. 2020. Soil characteristics and CO2 emissions of ex-burnt peatland in Kubu Raya District, West Kalimantan, Indonesia. Biodiversitas 21: 3691-3698. West Kalimantan, Indonesia has a large extent of tropical peatland with total ​​1.74 million ha with only 44.5% of such areas remaining as peat forest, while the rests have been converted into plantations, agricultural lands, and shrubs. The conversion of peat forest often uses fires to clear the vegetation and is followed by building canal to drain the water. The lack of vegetation combined with drought soil trigger uncontrolled escaped fire, especially in the dry season or El-Nino events, which is likely to affect soil characteristics and emit carbon dioxide. The purpose of this study is to examine the changes in soil characteristics both physical and chemical properties and to investigate CO2 emissions from peat soil post-fire. As a comparison, similar parameters were also assessed in non-burnt sites. The results showed significant differences in some peat soil characters both physically and chemically between ex-burnt and non-burnt peatland. The ex-burnt site had higher pH, available phosphorus and C/N ratio than those in the non-burnt site. Conversely, the total nitrogen and carbon contents, and cation exchange capacity were lower which is likely due to leaching. Peat fires also impacted physical characteristics of the soil such as increasing soil bulk density, reducing soil water content, soil temperature, especially in wet conditions. Carbon dioxide emissions in the ex-burnt site were considered higher than non-burnt site. These results could be brought out as a part of baseline data in managing ex-burnt peatlands to maintain a balance between carbon output and input and efforts on preventing peatland fires from becoming continuous carbon sources.
Electroporation-mediated genetic transformation of oil palm (Elaeis guineensis)
Authors: Darmawan Chris , Wiendi Ni Made Armini , Utomo Condro , Liwang Tony
Published: August 2020

Abstract. Darmawan C, Wiendi NMA, Utomo C, Liwang T. 2020. Electroporation-mediated genetic transformation of oil palm (Elaeis guineensis). Biodiversitas 21: 3720-3726. Novel traits introduction to existing varieties may shorten the duration of oil palm genetic improvement. This approach heavily relies on efficient plant transformation and regeneration methods. Commonly used methods such as biolistic and Agrobacterium-mediated transformation still generated low efficiency for oil palm. Therefore, it is important to find alternative transformation methods that have the potency to give better results. Electroporation is usually used for delivering genes into bacteria or plant protoplast where cell wall does not exist, however, in this research, it was used to deliver plasmid into plant tissues. The aim of this research is to establish an optimum electroporation protocol for delivering genes into oil palm calli. Electric field strength of 250, 500, 750, 1,000, and 1,250 V/cm were applied for oil palm calli electroporation. Transient GUS assay was not applicable for initial detection presumably due to oil palm endogenous GUS-like protein activity after electroporation. Delivered gene could be detected in survived calli from all tested electric field strength treatments and the highest calli growth rates were observed from 250 V/cm electroporation treatment. Overall results showed that electroporation could be used to deliver specific genes into oil palm calli and might be developed further to increase its efficiency.
Vegetative morphophysiological responses of four rice cultivars to drought stress
Authors: Miftahudin M , Putri Rury Eryna , Chikmawati Tatik
Published: August 2020

Abstract. Miftahudin, Putri RE, Chikmawati T. 2020. Vegetative morphophysiological responses of four rice cultivars to drought stress. Biodiversitas 21: 3727-3734. Each rice genotype develops certain morphophysiological responses to drought stress. The study aimed to analyze the morphophysiological responses of vegetative aspect of four rice cultivars to drought stress. A 10% Polyethylene glycol-6000 was added to a Yoshida nutrient solution medium as a drought stress stimulant for four rice cultivars, i.e., IR64, Hawara Bunar, Situbagendit, and Inpago 10. Fourteen-days-old rice seedlings were grown on the media with and without drought stress treatment for 9 days, and morphophysiological characters of vegetative aspects were observed. Drought stress inhibited the shoot growth of cv. Hawara Bunar, but increased shoot growth of cv. Inpago 10. The physiological responses in the form of leaf relative water content, proline, malondialdehyde (MDA), and total chlorophyll contents in cv. Hawara Bunar was inversely proportional to those of cv. IR64 showed an inferior response to drought stress. The rice cv. Hawara Bunar might develop better response mechanisms to drought than that of cv. IR64. The physiological responses of cvs. Situbagendit and Inpago 10 were in between the other two cultivars. We conclude that the variation of morphophysiological responses to drought stress among rice cultivars is an indicator of tolerance capability to drought that could be used as early-growth selection criteria in rice breeding programs for drought tolerance.
Soybean-maize intercropping feasibility under drought-prone area in East Java, Indonesia
Authors: Harsono Arief , Elisabeth Dian Adi Anggraeni , Muzaiyanah Siti , RIANTO SALAM AGUS
Published: August 2020

Abstract. Harsono A, Elisabeth DAA, Muzaiyanah S, Rianto SA. 2020. Soybean-maize intercropping feasibility under drought-prone area in East Java, Indonesia. Biodiversitas 21: 3744-3754. The study aimed to determine the land productivity, economic feasibility, and soybean cultivar which is suitable for intercropped with maize in maize production center on dryland-upland in East Java, Indonesia. The study was conducted in Semanding and Merakurak Sub-districts, Tuban District, East Java, Indonesia at the end of rainy season (March-July 2019). The study used a factorial randomized block design with three replications. The first factor was planting patterns, namely: soybean intercropping with maize, maize monoculture, and soybean monoculture. The second factor was soybean cultivars, namely: Argomulyo, Dena 1, and Dega 1. The maize variety used was NK Hybrid 212. The result of study indicated that by intercropping and selecting appropriate cultivar, soybean could be developed on dryland-upland area. Soybean intercropping with plant spacing of 30 cm x 15 cm and two seeds per-hill and maize in double row with plant spacing of (40 x 20) cm x 200 cm and one seed per-hill was able to produce maize seeds yield as high as maize increase LER by 1.69, and increase farming income. Dena 1 intercropping with maize was able to provide higher benefit, economic feasibility, and land-use efficiency than Argomulyo and Dega 1, even though Dega 1 had the strongest competitiveness, and Argomulyo had the higher soybean yield.
Sustaining farmers livelihoods through community forestry in Sikka, East Nusa Tenggara, Indonesia
Authors: Njurumana Gerson N. , Ginoga Kirsfianti , Octavia Dona
Published: August 2020

Abstract. Njurumana GN, Ginoga KL, Octavia D. 2020. Sustaining farmers livelihoods through community forestry in Sikka, East Nusa Tenggara, Indonesia. Biodiversitas 21: 3786-3796. One of the goals of managing global forest ecosystems today is to synergize their socio-economic, ecological and community livelihood benefits. Each forest type has various socio-economic and ecological characteristics that influence its management strategies and the provision services to the community. In general, the socio-economic benefits of forests in supporting community livelihoods are well known, however, the information which is specifically relevant to tropical monsoon forests is still very limited. This research aims to fill this knowledge gap, by providing information about the socio-economic conditions and provision of services of tropical monsoon forests to people's livelihoods. The research was conducted through structured interviews, FGDs, and field observations, by an analysis unit in community forests in the Sikka district. The information obtained was analyzed through descriptively qualitative and quantitative methods. The results showed an imbalance between the socio-economic conditions of people who rely on the tropical monsoon forest for their livelihoods and the carrying capacity of fuelwood, food, and fodder supply. This imbalance is due to the weak synergy and organization of stakeholders in optimizing how the provision services of forests are used to support farmers' livelihoods. Farmers' dependence on the tropical forest services is still high, therefore the strengthening of farmers' institutions becomes a key factor that determines sustainable management of the forest and enhances the value of its benefits to the community.
The effectiveness of 60Co gamma-ray exposure to the reproductive systems of rat (Rattus argentiventer) as sterile male technique
Authors: Sutapa Gusti Ngurah , Supartha I Wayan , WIJAYA I NYOMAN , PUJA I KETUT , Syaifudin Mukh
Published: August 2020

Abstract. Sutapa GN, Supartha IW, Wijaya IN, Puja IK, Syaifudin M. 2020. The effectiveness of 60Co gamma ray exposure to the reproductive systems of rat (Rattus argentiventer) as sterile male technique. Biodiversitas 21: 3805-3810. Various strategies have been implemented to control pests, however, these do not able to reduce rat attacks on rice plants. Therefore, the sterile male technique (SMT) using 60Co gamma radiation was introduced. A group of rats (Rattus argentiventer) of 2 months age were irradiated with 1-6 Gy doses (dose rate of 99.5631 cGy/min) and the quantity, morphology, and viability of spermatozoa of rats were assessed with standard procedures. The results showed that the concentration of spermatozoa was decreased with increasing radiation doses where for lower than 4 Gy were categorized as normal (>20 million/mL). The morphology of spermatozoa also decreased with increasing radiation dose where under 3 Gy were in normal (> 50%). Spermatozoa viability was also decreased where for doses 1 and 2 Gy were categorized as normal. Statistical analysis showed a significant difference (p<0.05) between the exposed group to control in spermatozoa quantity, morphology, and viability. This finding is quite similar with other experiments on the reproductive appearance of rat based on spermatozoa after irradiation. It is concluded that dose of 3 Gy that caused changes in spermatozoa with its viability still above 50% is the most appropriate dose for SMT of rice field rats.
In vitro somatic embryogenesis of superior clones of robusta coffee from Lampung, Indonesia: Effect of genotypes and callus induction media
Authors: Hapsoro Dwi , Hamiranti Rahmadyah , Yusnita Yusnita
Published: August 2020

Abstract. Hapsoro D, Hamiranti R, Yusnita Y. 2020. In vitro somatic embryogenesis of superior clones of robusta coffee from Lampung, Indonesia: Effect of genotypes and callus induction media. Biodiversitas 21: 3811-3817. This study aimed to investigate the effects of genotypes and primary callus induction media on somatic embryogenesis of superior robusta coffee clones of Lampung. Leaf explants of clones Tugusari, Komari, Tugino, and Wanto were cultured on two types of primary callus induction media (PCIM). PCIM1 consisted of half-strength MS salts, 30 gL-1 sucrose, added with (mgL-1) 0.1 thiamine-HCl, 0.5 nicotinic acids, 0.5 pyridoxine-HCl, 100 Myo-inositol, 200 ascorbic acids, 150 citric acids, and 1 benzyl adenine. PCIM2 consisted of NPCM salts, 30 gL-1 sucrose, added with (mgL-1) 15 thiamine-HCl, 1 nicotinic acid, 1 pyridoxine-HCl, 2 glycines, 130 Myo-inositol, 200 ascorbic acids, 150 citric acids, 1 2,4-dichlorophenoxyacetic acid, and 2 thidiazuron. The highest percentage (100%) of primary callus formation was found in Komari and Wanto clones. PCIM2 resulted in more primary calli than PCIM1. When subcultured to embryogenic callus induction medium, primary calli of clone Komari and Wanto developed into a high percentage of embryogenic calli, while those of the other two turned brown and died. PCIM2-derived primary calli developed into more embryogenic calli. When subcultured on somatic embryo (SE) regeneration medium, these calli underwent the formation of SE of various stages. When subcultured to plant regeneration medium, these SEs developed into plantlets.
Lipolytic bacteria and the dynamics of flavor production in Indonesian tempeh
Authors: Nur Naswandi , Meryandini Anja , Suhartono Maggy Thenawidjaja , Suwanto Antonius
Published: August 2020

Abstract. Nur N, Meryandini A, Suhartono MT, Suwanto A. 2020 Lipolytic bacteria and the dynamics of flavor production in Indonesian Tempeh. Biodiversitas 21: 3818-3825. During the process of tempeh maturation, lipolytic bacteria become an integral part of tempeh and even have important roles in determining the quality of resulting tempeh. This study was conducted to examine correlation between lipolytic bacteria which were present in three tempeh samples i.e. CMG, EMP, RTI, and their roles in liberation of free fatty acid. Lipolytic bacteria were found in each tempeh sample which were approximately 0.1 % of total bacterial population. CMG harbored the highest lipolytic bacterial population at 1.04 × 106 cfu g-1 followed by EMP at 2.88 × 105 cfu g-1, and RTI at 1.72 × 104 cfu g-1. Tempeh aroma and texture showed strong correlation between the numbers of bacterial population during the period or stages of tempeh maturation. Moreover, we also found a unique correlation between dynamic of lipolytic population and aroma changes. Free fatty acid profiling indicates that lipolysis activity was presence during fermentation of tempe where each tempeh samples showed some differences in liberation of dominant free fatty acid. 16S rRNA sequencing from a hundred of lipolytic isolates was identified and classified as member of the phylum Proteobacteria, Firmicutes, and Actinobacteria, other isolates were classified as uncultured clone.
Estimation of bacterial number in the water, sediment and biofilm of Badek and Mewek River (Malang, Indonesia) using Plate Count and eDNA Method
Authors: Ulinuha Devi , Andayani Sri , Hertika Asus Maizar Suryanto , Kilawati Yuni
Published: August 2020

Abstract. Ulinuha D, Andayani S, Hertika AMS, Kilawati Y. 2020. Estimation of bacterial number in the water, sediment, and biofilm of Badek and Mewek River (Malang, Indonesia) using Plate Count and eDNA Method. Biodiversitas 21: 3832-3836.  Several methods have been developed to quantify bacterial numbers in the environment, but the studies is still continued to provide the most effective and efficient method. This study was aimed to compare the capacities of two different methods (Plate Count and eDNA Method) to estimate the bacterial number in the water, sediment, and biofilm of Badek and Mewek River (Malang-Indonesia). The Plate Count Method was carried out on a Plate Count Agar (PCA) which was incubated for 24 hours at 37oC. The eDNA method was performed by slow agitation (1,800 rpm) to extract the environmental DNA of bacteria. Quantification of bacteria was obtained from the eDNA band intensity after electrophoresis in 1% gel agarose electrophoresis. Smartladder was used as a marker for the eDNA Method. The result showed that the eDNA Method was efficient for the estimation of bacterial numbers in the sediment and biofilm of Badek and Mewek River. However, this method was not suitable for estimating bacterial numbers in the water.
Distribution, variation, and relationship of Curcuma soloensis Valeton in Java, Indonesia based on morphological characters
Authors: JALIL MUHAMAD , PURWANTORO AZIZ , DARYONO BUDI SETIADI , PURNOMO Purnomo
Published: August 2020

Abstract. Jalil M, Purwantoro A, Daryono BS, Purnomo. 2020. Distribution, variation, and relationship of Curcuma soloensis Valeton in Java, Indonesia based on morphological characters. Biodiversitas 21: 3867-3877. Curcuma soloensis Valeton (locally called temu genyeh) was a plant originating from Solomon Islands and was synonymous with Curcuma longa L. This plant was often considered to be turmeric (Curcuma longa Linn.) or temulawak (Curcuma zanthorrhiza Roxb.), because the rhizome is almost the same color. The purpose of this study was to determine the distribution, variation, and relationship of C. soloensis in Java, Indonesia. Retrieval of data with exploratory roaming methods in 12 districts/cities in Java Island as a center for planting medicinal plants. Morphological character observations were made on habit, rhizome, roots, tubers, leaves, pseudo-stems, and flowers. Morphological data were analyzed by descriptive and numerical methods. Analysis of grouping with Gower Coefficients because it uses 45 binary and multistate data. Principal Component Analysis (PCA) was performed to determine the role of each character in the grouping. Cluster analysis and PCA graphics were assisted with MVSP 3.1 software. The results of the study were obtained from 25 accessions of C. soloensis in East Java (Trenggalek, Pacitan, Ponorogo), Central Java (Wonogiri, Karanganyar, Magelang, Semarang), Yogyakarta (Yogyakarta City, Bantul, Gunungkidul), and West Java (Ciamis and Tasikmalaya). The variation of C. soloensis lies in habit, stem color, leaf shape, rhizome shape, rhizome flesh color, and tuber shape. The highest abundance percentage is in Pajangan, Tirtomoyo, and Tawangmangu. The dendrogram divides 32 OTUs into two clusters on the phenon line 0.617, namely cluster A (C. zanthorrhiza) and cluster B (C. soloensis and C. longa). PCA results showed that the characters that had the most role in grouping were leaf blade color, leaf blade length, rhizome shape, root color, rhizome taste, outer and inner rhizome flesh color.
Ethnobotany of Amorphophallus paeoniifolius: Morphology, folk classification, and habitat in area around Ciremai Mountain, Cimanuk Watershed Region, West Java, Indonesia
Authors: MUTAQIN ASEP ZAINAL , KURNIADIE DENNY , ISKANDAR JOHAN , NURZAMAN MOHAMAD , Partasasmita Ruhyat
Published: August 2020

Abstract. Mutaqin AZ, Kurniadie D, Iskandar J, Nurzaman M, Partasasmita R. 2020. Ethnobotany of Amorphophallus paeoniifolius: Morphology, folk classification, and habitat in area around Ciremai Mountain, Cimanuk Watershed Region, West Java, Indonesia. Biodiversitas 21: 3898-3909.  Plants that grow in the world have a diversity of names, characters, and growing environments. Likewise, plants that grow around Ciremai Mountain, including the Cimanuk Watershed, are very diverse in species and habitats. One species of plant in this region is Amorphophallus paeoniifolius (Dennst.) Nicolson. This plant is closely related to people's lives. This plant is a species of the tuber that has the potential to be used for various purposes. This study aims to determine the knowledge of the people about the ethnobotany of A. paeoniifolius especially the morphology, folk classification, and habitat with case studies in several villages in Cikijing Sub-district, Majalengka District which is ecologically located in the Ciremai Mountain neighborhood and, based on geography, is included in the Cimanuk Watershed. The qualitative method is used in this research. The data were collected through observation and semi-structured interviews or deep interviews with competent communities by focusing on their diversity. Data were analyzed by cross-checking, summarizing, and synthesizing and were narrated descriptively through an emic and ethical approach. The results showed that the people in the Ciremai Mountain neighborhood, namely Cipulus Village, Cilancang Village, Jagasari Village, and Sindangpanji Village, Cikijing Sub-district, Majalengka District knew names, morphology, and folk classification of A. paeoniifolius. This plant is popularly known as suweg in local name. People's knowledge related to morphology (leaves, tubers, roots, and flowers) in these areas is generally not much different. Related to folk classification, people generally say that suweg has variant based on the color of the tubers and sunlight exposure to the place of growth. The intended variant is suweg with reddish-white and yellowish-white of the tuber flesh’s color. Another classification is the suweg variant which grows in the hieum (shading area) and negrak (open area). Concerning hábitat, the people informed that the suweg grows in the garden and homegarden (specifically in the Sindangpanji village, the people said that besides growing in both types of land, the suweg also grows on the edge of rice fields and ponds). Besides, suweg also grows in hot and cold (tiis) conditions; from the beginning of the rainy season to the beginning of the dry season, which is marked by yellowing and falling of leaves; in various soil conditions (such as red, black, brown or sandy soil); and with various species of plants (except with eurih and areuy,in which the growth of the plant is not optimum).
Innovative optofluidics and microscopy-based rapid analysis of pathogens
Authors: Wang Hao , Shiveshwarkar Priyanka , Brzozowski Robert , Zhdanov Arseny , Shi Shulin , Eswara Prahathees , Pyayt Anna
Published: August 2020

The timely knowledge and prescription of the most suitable antibiotic to treat bacterial infections is critical for the recovery of patients battling life-threatening bacterial infections. Unfortunately, current standard-of-care approaches relies on the empiric prescription of an antibiotic, as determination of the most effective antibiotic requires multiple time-consuming steps. These steps often include culturing of the bacterium responsible for infection and subsequent antibiotic susceptibility testing. Here we introduce an optofluidic technology that allows us to capture bacterial cells efficiently and rapidly from different biological samples and use the captured cells for rapid antibiotic selection thereby bypassing the need to culture the bacterium.
7X multiplexed, optofluidic detection of nucleic acids for antibiotic-resistance bacterial screening
Authors: Meena G. G. , Wall T. A. , Stott M. A. , Brown O. , Robison R. , Hawkins A. R. , Schmidt H.
Published: August 2020

Rapid and accurate diagnosis of bacterial infections resistant to multiple antibiotics requires development of new bio-sensors for differentiated detection of multiple targets. This work demonstrates 7x multiplexed detection for antibiotic-resistance bacterial screening on an optofluidic platform. We utilize spectrally multiplexed multi-spot excitation for simultaneous detection of nucleic acid strands corresponding to bacterial targets and resistance genes. This is enabled by multi-mode interference (MMI) waveguides integrated in an optofluidic device. We employ a combinatorial three-color labeling scheme for the nucleic acid assays to scale up their multiplexing capability to seven different nucleic acids, representing three species and four resistance genes.
40 Gsymbol/s channel-based Nyquist wavelength division multiplexing communication in a terahertz-band using optical-domain reception signal processing
Authors: Takiguchi Koichi
Published: August 2020

Nyquist wavelength division multiplexing (WDM) using a 40 Gbit/s channel signal is applied to terahertz (THz)-wave communication with a view to increasing its spectral efficiency and capacity. A 2 × 40 Gbit/s Nyquist WDM signal in the THz-band is both generated and demultiplexed by the assistance of optical technology. The optical-domain demultiplexing is adopted mainly due to the difficulty in both the direct THz-wave-domain and the subsequent radio-frequency (RF)-domain demultiplexing. The received THz-wave Nyquist WDM signal at an antenna is divided into two signals, which are down-converted into RF signals with heterodyne detection utilizing different frequency local sinusoidal waves. Each signal in the RF-domain is again transformed into an optical signal through an optical modulator, and each 40 Gbit/s channel is extracted from one of the generated sidebands at each optical modulator output with an optical Nyquist filter. Bit error rates (BERs) on the order of 10−5 and 10−7 (below the first KP4 forward error correction threshold) were obtained for the demultiplexed two 40 Gbit/s channels. In addition to the explanation of the experimental setup and operating principle of the optical-domain demultiplexing method for the THz-wave Nyquist WDM signal, some experimental results are reported to show the validity of our proposed demultiplexing method and factors to limit the BERs.
An Information Theoretic Image Steganalysis for LSB Steganography
Authors: Chhikara Sonam , Kumar Rajeev
Published: August 2020

Steganography hides the data within a media file in an imperceptible way. Steganalysis exposes steganography by using detection measures. Traditionally, Steganalysis revealed steganography by targeting perceptible and statistical properties which results in developing secure steganography schemes. In this work, we target LSB image steganography by using entropy and joint entropy metrics for steganalysis. First, the Embedded image is processed for feature extraction then analyzed by entropy and joint entropy with their corresponding original image. Second, SVM and Ensemble classifiers are trained according to the analysis results. The decision of classifiers discriminates cover image from stego image. This scheme is further applied on attacked stego image for checking detection reliability. Performance evaluation of proposed scheme is conducted over grayscale image datasets. We analyzed LSB embedded images by Comparing information gain from entropy and joint entropy metrics. Results conclude that entropy of the suspected image is more preserving than joint entropy. As before histogram attack, detection rate with entropy metric is 70% and 98% with joint entropy metric. However after an attack, entropy metric ends with 30% detection rate while joint entropy metric gives 93% detection rate. Therefore, joint entropy proves to be better steganalysis measure with 93% detection accuracy and less false alarms with varying hiding ratio.
Applications of Machine Learning to Estimating the Sizes and Market Impact of Hidden Orders in the BRICS Financial Markets
Authors: MAAKE Witness , VAN ZYL Terence
Published: August 2020

The research aims to investigate the role of hidden orders on the structure of the average market impact curves in the five BRICS financial markets. The concept of market impact is central to the implementation of cost-effective trading strategies during financial order executions. The literature is replicated using the data of visible orders from the five BRICS financial markets. We repeat the implementation of the literature to investigate the effect of hidden orders. We subsequently study the dynamics of hidden orders. The research applies machine learning to estimate the sizes of hidden orders. We revisit the methodology of the literature to compare the average market impact curves in which true hidden orders are added to visible orders to the average market impact curves in which hidden orders sizes are estimated via machine learning.

The study discovers that: (1) hidden orders sizes could be uncovered via machine learning techniques such as Generalized Linear Models (GLM), Artificial Neural Networks (ANN), Support Vector Machines (SVM), and Random Forests (RF); and (2) there exist no set of market features that are consistently predictive of the sizes of hidden orders across different stocks. Artificial Neural Networks produce large R2 and small Mean Squared Error on the prediction of hidden orders of individual stocks across the five studied markets. Random Forests produce the most appropriate average price impact curves of visible and estimated hidden orders that are closest to the average market impact curves of visible and true hidden orders. In some markets, hidden orders produce a convex power-law far-right tail in contrast to visible orders which produce a concave power-law far-right tail. Hidden orders may affect the average price impact curves for orders of size less than the average order size; meanwhile, hidden orders may not affect the structure of the average price impact curves in other markets. The research implies ANN and RF as the recommended tools to uncover hidden orders.