Agriculture and Natural Resources

Effectiveness of water spinach (Ipomoea reptans Poir) in mitigating acetylcholinesterase inhibition caused by organophosphate and carbamate pesticide

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: Organophosphate (OP) and carbamate (CB) pesticides pose health risks by inhibiting acetylcholinesterase (AChE). Evaluating water spinach (Ipomoea reptans Poir) as a remedy could provide a natural, accessible, and non-toxic remedy to counteract pesticide exposure.
Objectives: To evaluate the effectiveness of water spinach in reducing AChE inhibition caused by OPs and CBs, and to assess its toxicity using a GT-Pesticide Residue Test Kit.
Materials & Methods: Gas chromatography and mass spectroscopy (GC-MS) were used to analyze important chemical compounds. The quantity of water spinach to reduce inhibition of AChE by OP and CB pesticides was investigated using spectroscopic techniques.
Results: The sample tube colors were clearer than the control (I₀, I₅₀ =control and B1, L1, T1 = branch, leaf and top, respectively, of I. reptans with pesticide in the ratio of 1:1 (2.5 g:2.5 g) and B2, L2, T2 = branch, leaf and top, respectively, of I. reptans without pesticide, except L1 (I₅₀). Based on GC-MS, the water spinach contained alcohol functional groups, facilitating nucleophilic substitution reactions, which reduced AChE inhibition by OPs and CBs. Spectroscopic analysis showed differing efficiencies: I. reptans reduced OP inhibition (3 times hydrolysis) better than CB inhibition (2 times hydrolysis). I. reptans tea was non-toxic to human gingival fibroblast at concentrations of 0.0001–1 mg/mL.
Main finding: Water spinach consists of important compounds that could reduce the inhibition of AChE caused by OPs and CBs, as well as reducing the inhibition of OPS to a greater degree than the inhibition of CBs.

Integrated approaches to manage mustard aphid Lipaphis erysimi (Kaltenbach): An update

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: This review paper compared and elaborated on recent updates about various effective approaches to control mustard aphid.
Objectives: To promote environmentally friendly and ecologically beneficial research in the field of pest control without compromising production in field crops.
Materials & Methods: Various important and economically effective approaches against mustard aphid were compiled. Different approaches were compared from an economic viewpoint. Promotion of integrated approaches was based on the research findings of various scientists in respective fields.
Results: Comparative management of aphids through various approaches is a keen area of interest to farmers as well as researchers. Undoubtedly, chemical approaches offer most effective control compared to all other approaches; however, the toxicity and residual effects of chemicals disturb the ecological balance. The tendency of researchers to move to integrated approaches was notable and could be an effective way to reduce the chemical loads on the environment. The use of cultural, mechanical, biological, botanicals and chemical controls in combination are long-term and sustainable approaches to manage the impact of mustard aphid in mustard fields. Therefore, a sound integrated pest management module should be developed with the objective of integrating all possible management practices that are environmentally vibrant and effective to manage the aphid catastrophe in mustard fields.
Main finding: Chemical insecticides should only be applied in situations where the aphid population is far above the economic threshold level, and if so, only systemic insecticides at recommended dosages should be used as these pose minimum harm to natural enemies in the mustard ecosystem.

Forecasting model based on morphological characteristics for yield of konjac (Amorphophallus muelleri Blume) planted in Tak province, Thailand

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: The useful part of konjac (Amorphophallus muelleri Blume) is its tuber; however, it is difficult to estimate its annual production without weighing the tubers. The newly developed forecasting model aims to provide valuable insights and support decision-making processes related to productivity management, marketing and crop planning.
Objectives: To study the relationship between konjac tuber weight and vegetative morphological factors.
Materials & Methods: Data were collected from 163 individual konjac plants growing in sample plots. The vegetative morphological factors measured were: stem diameter at ground level, stem height, length of the longest leaf, crown cover, number of bulbils, tuber diameter and tuber weight. A model was developed to forecast konjac productivity using stepwise multivariate regression.
Results: The study identified correlations between the vegetative morphological factors of A. muelleri, with the stem diameter at ground level (D₀) being the most reliable factor. The equation used to predict A. muelleri tuber weight (Y) was log Y = –3.34 + 2.17 log D₀, which had a high coefficient of determination (0.95, p < 0.01). However, this equation was specific to A. muelleri productivity in Tak province.
Main finding: The developed equation should be valuable for tuber weight estimation without the need for tuber extraction. It should assist stakeholders to meet market demand.

Development and validation of markers to improve heat tolerance in flowering stage of Laos elite rice cultivar

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: Rice is sensitive to high temperatures in almost all its growth stages, with temperature being a major factor causing poor seed-setting rates.

Objectives: To validate molecular markers linked to two quantitative trait loci associated with high-temperature spikelet fertility, namely qHTSF1.1 and qHTSF4.1

Materials & Methods: F₂ lines were grouped as H1 and H2 with the HXBF2 allele at qHTSF1.1 and the N22 and HXBF2 alleles at qHTSF4.1, respectively, while groups H3 and H4 had the N22 allele at qHTSF1.1 and the N22 and HXBF2 alleles at qHTSF4.1, respectively. Stressing was done at 40–45°C for 6 hr from the booting to the harvesting stage. Pollen viability and spikelet fertility were used to assess tolerance to heat.

Results: Parental lines were significantly different for pollen viability and spikelet fertility under heat stress. N22 was not affected by high temperatures, while HXBF2 showed a severe reduction in pollen viability (66%). N22 maintained 76% spikelet fertility under heat stress, making it moderately tolerant to heat stress with an 11% reduction against the 25% reduction in spikelet fertility of HXBF2. Under heat stress, the F₂ lines of groups H1 and H3 had similar pollen viability scores to N22, while only the H1 group could be classified as heat-tolerant, maintaining good spikelet fertility.

Main finding: The efficiency of marker-assisted selection was confirmed in the F₂ 3-way population phenotyped for pollen viability and spikelet fertility under heat stress conditions. The molecular markers, particularly qHTSF4.1, should be very useful for marker-assisted selection breeding.

Diethylphosphonate-containing aminoacyl-adenosine analog as inhibitor of bacterial tRNA-dependent transamidase

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: The inhibitory activity of a transition state mimic of a bacterial tRNA-dependent transamidase could help in the control of many bacterial pathogens.
Objectives: To design, synthesize and test the inhibitory activity of a transition state mimic of a bacterial tRNA-dependent transamidase.
Materials & Methods: An aminoacyl-adenosine analog was synthesized and evaluated for its inhibitory activity against GatCAB, a tRNA-dependent transamidase. The saturation transfer difference nuclear magnetic resonance (STD NMR) experiments revealed binding epitopes. The disc diffusion method was conducted to test antibacterial properties, with molecular docking simulations elucidating the binding mode of the compound.
Results: Compound 1, a non-hydrolyzable aminoacyl-adenosine analog featuring the sulfone and diethylphosphonate groups, was synthesized from 3-deoxy-3-aminoadenosine and NHCbz-L-cysteine. The synthesized compound retarded the transamidation rate of GatCAB by approximately 30%. In addition, the STD NMR analysis indicated binding epitopes of compound 1, highlighting interactions involving the hydrogens in the diethylphosphonate, anomeric position and the adenine ring. Molecular docking simulations further elucidated the binding mode of compound 1 at the GatB transamidation site. Nonetheless, compound 1 did not exhibit in vivo antibacterial effects against Pseudomonas aeruginosa, Staphylococcus aureus or Bacillus subtilis, presumably due to cell permeability issues.
Main finding: The inhibition was highlighted of the tRNA-dependent transamidase, a novel target for antimicrobial development. Further structural modification to enhance membrane permeation could provide an antibacterial agent with a novel mechanism of action.

Application of unmanned aerial vehicle with computer vision as a tool for welfare monitoring of cage-cultured, river-based hybrid red tilapia

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: An unmanned aerial vehicle (UAV) was used to monitor cage-cultured red tilapia and provide cost-effective welfare insights by correlating fish swimming velocity (FSV) with environmental factors.
Objectives: To investigate the relationship between FSV and the rearing environment by combining computer vision techniques and a UAV.
Materials & Methods: Data were collected from five cages in two rearing crops. The UAV was flown in the morning and evening (1 hour before feeding), with a total of 22 flights. Tracker software was utilized for FSV analysis. Water quality parameters, fish weight (FW), water temperature (Temp) and nitrite-nitrogen (NO₂-N) were measured.
Results: The results showed that FSV had a positive correlation with FW (p < 0.01), Temp (p < 0.05) and NO₂-N (p < 0.05). The FSV (in centimeters per second) could be obtained from the regression equation FSV = -7.681 + 0.007 FW + 0.416 Temp + 13.909 NO₂-N with a coefficient of determination of 0.701. There was no significant difference between FSV and the estimate obtained using the tracking software (p > 0.05).
Main finding: The study utilized UAV and computer vision technology to monitor the welfare of cage-cultured red tilapia. There were positive correlations between FSV and FW, Temp and NO₂-N, demonstrating a straightforward and effective approach to assessing aquaculture welfare. These results underscored the efficacy of UAV and computer vision in monitoring fish behavior, providing a cost-effective method. The findings should have important implications for enhancing farm management practices and advancing scientific knowledge in tilapia farming, ultimately leading to improvements in fish welfare and overall production efficiency.

Novel eco-friendly design and fabrication: Application of low-cost, smokeless, mobile charcoal furnace and wood vinegar products for aging society

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: A low-cost, smokeless, mobile charcoal furnace with a wood vinegar product condensing system was fabricated. It is environmentally friendly and suitable for the elderly. The developed furnace can increase productivity compared to existing conventional units and can be operated easily by the elderly to generate charcoal for income.
Objectives: To develop and evaluate a portable, smokeless charcoal furnace equipped with a wood vinegar condensation system to enhance the efficiency of charcoal production, reduce the required production time, and improve the quality of the charcoal produced. Additionally, the study also analyzes its economic viability.
Materials & Methods: The production of charcoal involved exposing bamboo and Acacia auriculiformis wood to 200°C, 250°C or 300°C for 5 hr, 6 hr or 8 hr. The quality of the resulting charcoal was determined based on several factors: heating value, weight, yield, moisture content and the amount of wood vinegar generated.
Results: The charcoal furnace system had the highest capacity, producing 7 kg/hr of charcoal. It took 5 hr to complete the burning process and an additional 15 min to remove the charcoal. Engineering economic analysis was used to determine the viability of using the portable, smokeless charcoal furnace. It was determined that the cost of production was USD 0.18 /kg. The break-even point for this operation was 12 hr/yr and the payback period was 0.021 yr.
Main finding: The charcoal kiln system could be moved to different locations and was suitable for elderly workers. The quality of charcoal products was higher than the products available on the market and their value was increased by adding a wood vinegar condensation system.

Quantification of antioxidant and antimicrobial properties of oil palm empty fruit bunch lignin based on organosolv extraction

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: Lignin from an oil palm empty fruit bunch (OPEFB) sample was extracted using an organosolv technique to characterize the antioxidant and antimicrobial properties.
Objectives: To optimize the OPEFB extraction conditions for lignin using different mixtures of organic acid solution and extraction times.
Materials & Methods: OPEFB samples were pretreated using dilute sulfuric acid, followed by organosolv extraction. The most effective extraction conditions were identified for producing lignin. This lignin was characterized based on Fourier-transform infrared (FTIR) spectroscopy and various properties, including molecular weight, particle size, total phenolic content (TPC) and antioxidant and antimicrobial activities.
Results: The study involved pretreating OPEFB with 8% (volume per volume) sulfuric acid, then extracting with different mixtures of organic acid containing formic acid (FA), acetic acid (AA), and water (H₂O) and using different extraction durations. The optimal extraction conditions were achieved by combining FA/AA/H₂O in the ratio 30:60:10% (volume per volume per volume) and maintaining it for 60 min. The mean (± SD) effectiveness of lignin extraction was 44.1 ± 0.06%. The purity of the extracted lignin was 92.2 ± 0.21%, comprising 91.0 ± 0.22% acid-insoluble lignin and 1.16 ± 0.02% acid-soluble lignin. The produced lignin had a small molecular size and most functional groups were phenol hydroxyl groups, which affected the antioxidant and antimicrobial activities.
Main finding: The organosolv technique showed potential for lignin extraction from OPEFB. This method not only uses greener chemicals compared to conventional approaches but also identified antioxidant and antimicrobial activities as a way of adding value to agricultural waste materials.

Anti-inflammatory effects of snow mushroom (Tremella fuciformis) drinks with different types of natural sweeteners on RAW 264.7 macrophages stimulated with lipopolysaccharide

Kwanchanok Hunthayung, Sassy Bhawamai — Fri, 28 Jun 2024 00:00:00 +0700

Importance of work: Snow mushrooms are a food ingredient commonly consumed worldwide. However, few reports exist concerning their health benefits.
Objective: To investigate the bioactive compounds, antioxidant activities and immune response of snow mushroom drinks, including sugar and natural sweetener effects.
Materials & Methods: Snow mushrooms were soaked, boiled at 95°C for 10 min, mixed with different types of natural sweetness and sterilized by retort. Before testing, the drinks were ground, centrifuged and the supernatant was collected to test activity.
Results: The black and white snow mushroom drinks had 2.74 g/100 mLand 3.54 g/100 mL of β-glucan content, respectively. The white snow mushroom drinks with longan had the highest total phenolic content at 329.37 ± 27.23^a μg gallic acid/mL, followed by white snow mushroom with monk fruit, original white snow mushroom, black snow mushroom and no sugar white snow mushroom, respectively. Nonetheless, all treatments showed similar anti-inflammatory effects by decreasing nitric oxide and tumor necrosis factor-α cytokine production in lipopolysaccharide-induced RAW 264.7 macrophages.
Main finding: The snow mushroom drinks could be used as an alternative functional drink. Different types of natural sweeteners did not affect the anti-inflammatory effect.

Genetic analysis evidence of population substructure within the endangered Irrawaddy dolphin (Orcaella brevirostris Gray, 1866) in Thailand and Indonesia

Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: The decline in numbers of the Irrawaddy dolphin threatens its viability. Genetic data scarcity imperils management decisions.
Objectives: To apply microsatellite-based analysis to assess the genetic diversity and population structure of the Irrawaddy dolphin in Thailand and Indonesia.
Materials & Methods: Skin and muscle samples were collected from stranded Irrawaddy dolphins in coastal and riverine areas of Thailand (n = 64) and Indonesia (n = 10). Individual DNA was analyzed using 12 microsatellite primers. However, DNA from only 15 individuals from Thailand and five from Indonesia could be successfully amplified. The data obtained were then used to assess population genetic parameters and population structure.
Results: A high level of genetic diversity was observed among Irrawaddy dolphin populations in Thailand and Indonesia. In total, 106 alleles were identified across four populations in Thailand and Indonesia, with mean observed heterozygosity (H_o) of 0.625 ± 0.048 and an allelic richness of 4.125 ± 0.182. Pairwise population differentiation and discriminant analysis of principal components supported significant population heterogeneity. These findings suggested a population structure within Irrawaddy dolphins across Thailand and Indonesia, contradicting the common assumption of panmixia in marine mammal populations.
Main finding: Genotyping data revealed a population substructure within Irrawaddy dolphin populations in Thailand and Indonesia, highlighting potential challenges for their long-term conservation.

Effectiveness of water spinach (Ipomoea reptans Poir) in mitigating acetylcholinesterase inhibition caused by organophosphate and carbamate pesticide

Fri, 28 Jun 2024 00:00:00 +0700

Survey of bovine leukemia virus genotypes from Thai swamp buffaloes raised in central and eastern Thailand

Thuchadaporn Chaikhun-Marcou, Prayuth Saekhow — Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: Bovine leukemia virus (BLV) is a known etiologic agent of enzootic bovine leukosis in cattle and has also been observed in buffaloes. The genotyping of BLV based on the gp51-env gene has been conducted exclusively in cattle, but there are no studies in buffaloes.
Objectives: To identify the genotypes of BLV among Thai buffaloes raised in central and eastern Thailand.
Materials & Methods: Polymerase chain reaction (PCR) and BLV-specific primers were used to perform proviral DNA detection of BLV. Then, the genotype was detected from nucleotide sequences of the gp51-env gene based on phylogenetic analysis.
Results: Nested PCR showed that the occurrence of the BLV provirus in the Thai-buffalo blood samples was 23.1% (42/182). A phylogenetic tree assay showed that the 24 partial nucleotide sequences of the Thai swamp-buffalo BLV gp51-env gene belonged to genotype1. Evolutionary trees obtained from reference-cattle BLV nucleotide sequences selected based on similarity to a representative of Thai swamp-buffalo BLV nucleotide sequences (OB BLV6) were used to internally validate genotype 1. The buffalo-circulating BLV and bovine-circulating BLV were shown to be part of a distinct clade.
Main finding: The evolutionary phylogenetic tree showed that all the samples were genotype 1, but there were significant differences between buffalo-circulating BLV and bovine-circulating BLV. Hence, some features may diverge, at least in the gp51-env genes.

Anatomical and histochemical responses of Senggani (Melastoma malabathricum L.) grown in different soil types

Annisa Safitri, Laurentius Hartanto Nugroho, Diah Rachmawati, Maryani — Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: Senggani (Melastoma malabathricum L.) grows in various habitats and contains several secondary metabolites, offering several benefits. However, no published study has investigated the anatomical characteristics and distribution of secondary metabolites related to plant adaptation at the tissue level in Senggani grown in different soil types.
Objectives: To analyze anatomical characteristics and tissue distribution of secondary metabolites of Senggani grown in different soil types (Mediterranean, latosol and regosol).
Materials and Methods: Anatomical slide preparation was carried out using a paraffin embedding method, while a histochemical technique was used to observe the distribution of phenolics, terpenoids and alkaloids.
Results: The Mediterranean soil type produced the highest stem periderm thickness and leaf trichomes index, with the lowest epidermal thickness and number of stem xylem vessels. The latosol had the highest root cortex thickness, root xylem vessel diameter, sponge thickness and leaf xylem vessel diameter. Furthermore, plants grown on the regosol had the highest root stele diameter, stem xylem vessel number, stomatal size and leaf trichome density. Qualitatively, the Mediterranean and regosol soil types produced a higher distribution of phenolics, terpenoids and alkaloids compared to the latosol. The predominant site for secondary metabolites in roots was in the parenchyma of the phloem and xylem. In stems, these compounds were concentrated in xylem vessels and distributed in the trichomes, epidermis and mesophyll, as well as in the parenchymal cells of midribs and vascular tissues from leaves.
Main finding: M. malabathricum could grow in Mediterranean, latosol and regosol soils. Plants grown in the latosol soil had better anatomical characteristics but a reduced secondary metabolite distribution compared to the Mediterranean and regosol soils.

Investigating correlation of soybean (Glycine max (L.) Merill) seed germination with rhizosphere bacterial abundance based on polymerase chain reaction and metagenomic analysis

Paul B Timotiwu, Wawan A Setiawan, Tumiar K Manik, Adinda N Putri — Fri, 28 Jun 2024 00:00:00 +0700

Importance of the work: Production of soybeans may be enhanced through optimal seed viability.
Objectives: To investigate the possibility that good viability soybean seeds in the germination phase will produce abundant bacteria in the rhizosphere.
Materials & Methods: Four seed genotypes were analyzed based on germination percentage and radicle emergence. Bacterial DNA was extracted using a Genomic Purification Kit and analyzed using a nanophotometer. The 16S rRNA gene sequencing was amplified using the 63F and 1387 R primers and subsequently visualized using capillary electrophoresis. Bacteria were identified using metagenomic analysis and verified using the nanophotometer and a fluorometer and sequenced using nanopore technology.
Results: All soybean seed from the four different genotypes had high values for germination percentage (>96%) and radicle emergence (>85%). However, rhizophore bacterial abundance varied among the four genotypes. The results of DNA extraction showed the highest abundance of rhizosphere bacteria in the Argomulyo genotype, followed by Dena-1, Anjasmoro and Devon-1, respectively. However, based on DNA band visualization, the Anjasmoro genotype had the highest abundance, followed by Argomulyo, Dena-1, and Devon-1, respectively. Rhizosphere bacterial abundance was related more to genotype character. The rhizosphere was mostly dominated by Gram-negative bacteria, indicating that the rhizosphere was occupied by the Proteobacteria phylum, which is common in soil ecosystems. In addition, the study showed that bacteria of the genera Pseudomonas, Lysinibacillus and Clostridium dominated the bacterial community of the soybean rhizosphere.
Main finding: Even though soybean seeds from different genotype had good viability, the rhizosphere bacteria might be different in the soil in which the seed have been planted. This finding implied that rhizosphere bacterial abundance might be an indicator for choosing good genotypes in soybean cultivation.