Metal Oxides as Soluble Nano Catalyst on Biodiesel: A Review

Nano particles of metal oxide developed as soluble nano additive in liquid fuels to improve fuel quality. One application of nano metal oxide particles is an additive to biodiesel. Biodiesel is an alternative fuel that can reduce dependence on fossil fuels. Pure biodiesel has a relatively lower calorific value compared to fossil fuels. Low calorific value results in increased brake specific fuel consumption. Moreover, biodiesel has a higher density and viscosity compared to fossil fuel. The content of carbon monoxide (CO), unburned hydrocarbons (HC) and nitrogen oxide (NOx) in exhaust gases with biodiesel is higher than fossil fuels. Metal oxide nanoparticles are added to biodiesel between 6 to 80 nm with concentrations about 50 to 500 ppm. Addition of metal oxide nanoparticles to biodiesel can improve brake thermal efficiency, reduce brake specific fuel consumption, carbon monoxide (CO), unburned hydrocarbons (HC), nitrogen oxide (NOx) and improve carbon dioxide (CO2) emission due to the catalytic effect of metal oxide nanoparticles. Metal oxide acts as an oxidation catalyst thereby reduce the carbon combustion activation temperature and thus enhances hydrocarbon oxidation, promoting complete combustion. Nanoparticles that are often used in various studies are nickel (II) oxide (NiO), cerium (IV) oxide (CeO2), titanium oxide (TiO2), zinc oxide (ZnO), aluminum oxide (Al2O3), and silicon dioxide (SiO2). This review paper describes the progress and development of nano metal oxide applications as additives for biodiesel, and the discussion in this paper is divided into 3 main topics, including the effects of nanoparticles on the properties of biodiesel, engine performance, and emission characteristics.

Phenotypic Variability of The F2 Populations Derived from Crosses Between Local and Introduced Okra Cultivars

Okra (Abelmoschus esculenthus) is a vegetable plant consumed in immature and tender texture fruits. Crosses of local okra with introduced varieties are carried out to improve the character of the local cultivars. This study aimed to assess the variability of agronomic characters, both quantitative and qualitative characters of various families of the F2 populations and select superior families that can be used to produce new cultivars. The F2 population was derived from inbreeding and selection of the crosses between local okra cultivars with B291 and Ve022 as introduced cultivars. The study used an experimental method with an individual observation. Qualitative characters were described based on the descriptor by IBPGR, while quantitative characters were analyzed using descriptive statistics. Results showed variation in each F2 family in plant height, the number of flowers per plant and the number of fruits per plant, except for SOMB291-16. FOHVE022-8, FOHB291-15, FOHVE022-17, SOMB291-23 and SOMB291-24 families could be selected due to the extended picking time were in line with the increase of fruit quality. A broad variability of quantitative characters was found for all characters, indicating a high opportunity to obtain valuable traits and desirable segregants in F2 populations. Variations in qualitative characters were found in stem color, leaf shape, fruit color and fruit shape. The selection of plants with specific characters could be maintained with inbreeding or self-pollinated desirable segregants.

Growth and Yield of Soybean on Various Types and Concentrations of Liquid Organic Fertilizer in Ultisols

The application of a wed-based liquid organic fertilizer can increase the production of black soybeans (Glycine Max L. Merril). The study aimed to identify the best source and dose of liquid organic fertilizer (LOF) for black soybean growth and yield. The researchers used a three-times-repeated Completely Randomized Design (CRD) using a factorial layout. The first factor was the source of LOF, which included Siam weed (Chromolaena odorata, L.), Goat weed (Ageratum conyzoides L.), and yellow creeping daisy (Wedelia trilobata L.). The second factor was the concentration of weed-based LOF, consisted of water (control treatment); 12 ml/L; 16 ml/L; 20 ml/L. The results of the study show, weed-based LOF, namely LOF Yellow creeping daisy, Goat weed, and Siam weed, resulted in no significant difference in the growth and yield of the black soybean. Except for the variables of root fresh weight and number of pods per plant, the variation in concentration of weed-based liquid organic fertilizer had no significant effect on plant growth and yield.

Potential of Intercropping of Oil Palm (E. guineensis Jacq.) and Liberica Coffee (C. liberica L.): A Case Study in Smallholder Plantation

Oil palm (Elaeis guineensis Jacq.) has become the main plantation commodity in Indonesia. Climate change phenomena and competitiveness fluctuation of palm oil commodities have led to increased need for optimized land productivity while maintaining sustainability. This research aimed to study the potential of oil palm intercropping with liberica coffee (Coffea liberica L.) in several smallholder oil palm plantations in Riau Province, Sumatera Island, Indonesia. Measurements in the middle of the non-harvesting path of oil palm showed the age of oil palm is directly proportional to the difference between air and soil temperature and relative humidity under canopy. Oil palm roots were dominantly distributed vertically in solum 0 - 30 cm and always dominant compared to coffee at all horizontal distances observed. While the dominant root coffee distribution was in solum 31 - 60 cm. Analysis results show the tap roots extend no further than 30-45 cm below the soil surface. It was known that oil palm roots are dominantly distributed at a distance of 2-3 m from the trunk while the coffee roots are dominantly distributed at a distance of 1-2 m from the trunk. Analysis of oil palm yields in the intercropping system showed no significant decrease compared to monocropping systems with relatively the same age and production input. Coffee production per tree has decreased by 25-30% compared to the average production in monocropping systems.

Antifungal Activity of Essential Oils of Leaves, Rhizomes Oils and Fraction Wild Ginger Elettariopsis Slahmong Ck Lim Inhibit The Colony Growth of Sclerotium Rolfsii

This study aims to see the effectiveness of essential oils of leaves, rhizomes and fraction of wild ginger Ellettariopsis slahmong CK Lim against the pathogenic fungus Sclerotium rolfsii which causes rot disease of the stem base of peanut plants an in vitro.The study consisted of two sub activities: (a) inhibited of colony diameter using Patato Dextrosa Agar (PDA) medium and (b) inhibited of colony biomass using Potato dextrose Broth (PDB) medium, the treatments tested were leaf essential oil and rhizome of wild ginger and fractions A1, B2, C3 and D4, with concentration levels (0, 100, 250 and 500 ppm). Experiments (a) and (b) were arranged in the form of a Completely Randomized Design (CRD) in factorial each with 4 replications. The results showed that the leaf essential oil and rhizome of wild ginger and its fractions had the potential to be used as a vegetable fungicide. The A1 fraction has the best antifungal effectiveness compared to the B2 fraction, leaf oil, rhizomes and other fractions, with the highest inhibition of diameter and biomass of S rolfsii colony the 49.47% and 51.46%. Essential oils of leaves and rhizome oil are not statistically significantly different, but in numerically leaf oil are better than rhizome oil. The C3 fraction showed the lowest colony diameter inhibition and biomass of 34.70% and 36.95%. The best concentration level in inhibition the growth of S rolfsii mushroom is 500 ppm, with inhibition of the diameter and biomass of the colony by 81.74% and 84.25%.

Growth and Yield Performance of Aromatic Fine Rice as Influenced by Varieties and Fertilizer Managements

This Research was conducted to investigate the effect of fertilizer management on growth and yield performance of aromatic fine rice varieties. The experiment consisted of two factors were aromatic fine rice and fertilizer management. There were four varieties namely Kalizira, Kataribhog, Tulshimala and BRRI Dhan34 with four fertilizer treatments recommended dose of fertilizers (T1), cowdung @ 10 tha-1 (T2), 50% of recommended dose of fertilizers + 50% cowdung(T3), 75% of recommended dose of fertilizers + 50% cowdung (T4). The result showed that BRRI Dhan 34 significantly superior for effective tillers number/ hill (18.46), panicles length (26.67cm), grains number/ panicle (146.30), harvest index (40.73 %), grain protein content (6.23%), grain yield (2.79 tha-1), straw yield (4.06 tha-1), and biological yield (6.85 tha-1). Among fertilizer management, the highest effective tillers number/hill (16.20), grains number/ panicle (142.45, panicles length (26.66 cm),1000 grain weight (13.75), grain protein content (10.2%), biological yield (6.30), were obtained from T3 treatment. Based on interaction effect showed that the highest effective tillers number/hill (18.36), grains number/ panicle (155.33), panicles length (26.73 cm), grain protein content (10.80%), biological yield (7.85) was found with BRRI Dhan 34 combined with T3 treatment. However, grain yield increased with the increase in nitrogen levels. Together tillers number/hill, grains number/panicle, grain protein content, harvest index, grain yield was the main responsible yield contributing characters to improve the yield quality of aromatic fine rice.

The Design and Building of Medium Capacity Drying House for Bokar

Bokar, processed rubber material, is latex obtained from rubber trees of community plantations. The quality of latex can be identified from its features which are white, relatively soft, and odorless. The purpose of this research was to design a simple rubber sheet drying house and examine the quality of dry rubber under Indonesian National Standard. Bokars are processed using a liquid smoke coagulant with a concentration of 10-15% and it obtained a clean white rubber although it has a slight smoke smell. Before drying, Bokar had ground to gain the thickness of the unsmoked sheet/ USS around 3-5 mm. The components of the drying house include the drying room, heating room, heater, thermometer, blower, plenum chamber, ventilation, drying room door, and electric motor. The capacity of the drying house is 200 kg of rubber sheet, with a drying temperature of 35 – 46oC and 6 hours drying time. The rubber produced has good quality with average dry rubber content (DRC) was 73.75%.

Stability and Toxicity Test of Angkak Pigment Powder from Sago Hampas- Rice Flour Substrate as Natural Dyes

Sago hampas is waste from processing sago starch. Sago hampas is generally thrown away without any further treatment. Sago hampas contain nutrients that can be used as a substrate for fermentation of angkak. The study aims to determine the stability and toxicity of angkak pigment powder from sago hampas-rice flour substrate. The study used exploratory research design through experiments in the laboratory. This study used the UV-vis spectrophotometer method in observing the stability of the Angkak powder pigment and the brine shrimps method of angkak pigment powder toxicity test. The results showed that the level of solubility of angkak pigment powder will increase at higher temperatures. Stability of angkak pigment powder tends to decrease with longer heating, the higher of heating temperature and the longer of irradiation. Angkak pigment powder are more stable at neutral and alkaline pH compared with acidic pH. And it is not toxic to experimental animals with LC50 value of angkak pigment powder of 2,897.05 ppm. The conclusion of this study is that temperature affects the intensity of the angkak pigment. Angkak is unstable along with heating time, heating temperature and longer of irradiation.

The Prospect of Knowledge Growing System (KGS) for Plant Disease Early Detection System

Editor's Corner

Identification of Local Rice Genotypes from Deli Serdang, North Sumatera, Indonesia to Drought Stress Condition

Regency of Deli Serdang in the Province of Sumatera Utara has high diversity of landrace rice that has adapted to various climatic and edaphic condition including drought. Studies on various local rice genotypes tolerant to drought is of important to be carried out. This will help plant breeders with germplasms for future breeding program. Polyethylene glycol (PEG) is a water-soluble compound with high osmotic pressure and unlikely to have specific interaction with biological chemicals. With these properties, PEG is often be used in studies of plant response to drought stress. The experiment reported here was aimed at determining rice genotypes, local to Regency of Deli Serdang, tolerant to drought. The experiment was carried out at Laboratory of Physiology and Glass House of Faculty of Agriculture, Universitas Islam Sumatera Utara, Medan from February to April 2020. A two-way factorial experiment was assigned in a completely randomized design (CRD) with 3 replicates. The first factor was 23 local rice genotypes plus 4 genotypes tolerant to drought and the second factor was the concentration of PEG 6000 i. e 0 and 20% (w/v). Observations included percent of germination, plant height, length and number of roots protruding from paraffin-wax layer, leaf chlorophyll content, seedling fresh and dry weight, index of tolerance, probability of resistance, and proline content. Data were analyzed with analysis of variance and mean separation of DNMRT at 5%. Results demonstrated that 6 local rice genotypes, Gemuruh, Ramos Merah, Arias, Sialus, Silayur, and Sirabut were resistant to drought stress under the experimental condition.