Genotype-by-environment interactions (GEIs) and evaluate superior sweet potato (Ipomoea batatas [L.] Lam) using combined analysis and GGE biplot.

Genetic studies on yield and yield quality are becoming benchmarks for farmers and industry in selecting and developing varieties. Evaluations that combine various stability statistics can provide more accurate information to select the ideal genotype. This study aims to identify the effect of genotype by environment interactions (GEIs) for yield and yield quality, to select high yield and stable sweet potato genotypes, as well as to select superior genotypes based on yield and yield quality. Three different environments in West Java, Indonesia, were used to test the sweet potato genotypes using a randomized block design that was repeated three times. Highly significant effects of sweet potato genotypes (G), environments (E), and GEIs were observed for yield and yield quality. The Combined ANOVA showed that GEIs effect contributed 54.88% for yield, 40.01% for sweetness, 10.46% for moisture content, 68.80% for tuber diameter, and 72.57% for tuber length from the sum of square. Five most high and stable yield on sweet potato genotypes identified by all measures, includes G4, G6, G7, G31, and G32. Genotype by yield*traits (GYT) selected seven genotypes that have superior in yield and yield quality, they were G7, G15, G4, G20, G6, G31, and G14. Based on stability measurements and GYT biplots, the genotypes G4, G6, G7, and G31 are in both slices. So that the four genotypes have high, stable yields, and have a good combination of traits for yield quality. Our findings can be used for improvement cultivation involving partner companies, partner institutions, and farmers, and the selected genotypes can be release as superior varieties candidate.

Breaking barriers to low-carbon development in Indonesia: deployment of renewable energy.

The Indonesian government is incorporating Low-Carbon Development (LCD) into its National Medium-Term Development Plan 2020-2024. In the future, the energy sector will become the largest carbon emitter unless the government commits to dissolving barriers to renewable energy expansion. Literature studies indicate four barriers to LDC namely socio-cultural, economic, technology, and governance. This research aims to examine the barriers that hinder the implementation of LCD in Indonesia and to analyze which barriers are most significant. This study uses mixed methods. Qualitative and quantitative data were generated during fieldwork in DKI Jakarta, Bali, West Nusa Tenggara, and Bangka Belitung provinces. The Partial Least Square - Structural Equation Modeling (PLS-SEM) approach was used to measure the direction and strength of the relationship. The qualitative approach is useful for further deepening the provincial context that was not captured from the previous approach. This study indicates that among those four barriers, technological and governance barriers have negative significant and direct effects on LCD, and governance needs to be treated as the most critical barrier. This study emphasizes the importance of collaboration between central and local governments in implementing LCD. Shared vision, equal responsibilities, commensurate governance roles, development of fiscal instruments, can improve the coherence and continuity of renewable energy development programs and activities.

Waste valorization using solid-phase microbial fuel cells (SMFCs): Recent trends and status.

This review article discusses the use of solid waste processed in solid-phase microbial fuel cells (SMFCs) as a source of electrical energy. Microbial Fuel Cells (MFCs) are typically operated in the liquid phase because the ion transfer process is efficient in liquid media. Nevertheless, some researchers have considered the potential for MFCs in solid phases (particularly for treating solid waste). This has promise if several important factors are optimized, such as the type and amount of substrate, microorganism community, system configuration, and type and number of electrodes, which increases the amount of electricity generated. The critical factor that affects the SMFC performance is the efficiency of electron and proton transfer through solid media. However, this limitation may be overcome by electrode system enhancements and regular substrate mixing. The integration of SMFCs with other conventional solid waste treatments could be used to produce sustainable green energy. Although SMFCs produce relatively small amounts of energy compared with other waste-to-energy treatments, SMFCs are still promising to achieve zero-emission treatment. Therefore, this article addresses the challenges and fills the gaps in SMFC research and development.

Pyrolysis of solid waste residues from Lemon Myrtle essential oils extraction for bio-oil production.

Solid waste residues from the extraction of essential oils are projected to increase and need to be treated appropriately. Valorization of waste via pyrolysis can generate value-added products, such as chemicals and energy. The characterization of lemon myrtle residues (LMR) highlights their suitability for pyrolysis, with high volatile matter and low ash content. Thermogravimetric analysis/derivative thermogravimetric revealed the maximum pyrolytic degradation of LMR at 335 °C. The pyrolysis of LMR for bio-oil production was conducted in a fixed-bed reactor within a temperature range of 350-550 °C. Gas chromatography-mass spectrometry showed that the bio-oil contained abundant amounts of acetic acid, phenol, 3-methyl-1,2-cyclopentanedione, 1,2-benzenediol, guaiacol, 2-furanmethanol, and methyl dodecanoate. An increase in pyrolysis temperature led to a decrease in organic acid and ketones from 18.09% to 8.95% and 11.99% to 8.75%, respectively. In contrast, guaiacols and anhydrosugars increased from 24.23% to 30.05% and from 3.57% to 7.98%, respectively.

Performance of a continuous flow microbial reverse-electrodialysis electrolysis cell using a non-buffered substrate and catholyte effluent addition.

A continuous flow microbial reverse-electrodialysis electrolysis cell (MREC) was operated under non-buffered substrate with various flow rates of catholyte effluent into anode chamber to investigate the effects on the hydrogen gas production. Adding the catholyte effluent to the anolyte influent resulted in increased salt concentration in the anolyte influent. The increasing anolyte influent salt concentration to 0.23M resulted in improved hydrogen gas production, Coulombic recovery, yield, and hydrogen production rate to 25±1.4mL, 83±5%, 1.49±0.15mol-H2/mole-COD, 0.91±0.03m3-H2/m3-Van/day, respectively. These improvements were attributed to the neutral pH rather than increase in anolyte conductivity as there was no significant improvement in the reactor performance when the NaCl was directly added to the reactor. These results show that addition of catholyte effluent into the anode chamber improved the MREC performance.

Hydrogen production in microbial reverse-electrodialysis electrolysis cells using a substrate without buffer solution.

The aim of this work was to use substrate without buffer solution in a microbial reverse-electrodialysis electrolysis cell (MREC) for hydrogen production under continuous flow condition (10 cell pairs of RED stacks, HRT=5, 7.5, and 15h). Decreasing in the HRT (increasing in the organic matter) made cell current stable and increased. Hydrogen gas was produced at a rate of 0.61m(3)-H2/m(3)-Van/d in H-MREC, with a COD removal efficiency of 81% (1.55g/L/d) and a Coulombic efficiency of 41%. This MREC system without buffer solution could successfully produce hydrogen gas at a consistent rate.