Malaysian Applied Biology

A Review of The Effects Of Light-Emitting Diodes (LEDs) on The Growth of Sunflower Microgreens and Their Nutritional Potential

Sreeramanan Subramaniam — 2024-11-30

Sunflower (Helianthus annuus) microgreens have become known as a potent source of essential nutrients and bioactive compounds with numerous health benefits. The microgreens industry has traditionally favored popular microgreens from the Brassicaceae family such as kale, rocket, and broccoli. Sunflower microgreens are characterized by their richness in vitamins, minerals, antioxidants, and phytochemicals that contribute significantly to a nutritious diet. However, their nutrient content can be influenced by various factors, including growing conditions and lighting. Light-emitting diodes (LEDs) offer precise control of light spectrum, light intensity, and lighting duration, enabling customized lighting systems optimized for growing sunflower microgreens. Pre-treatment and optimal harvest timing affect the quality and yield of microgreens, and sunflower microgreens are no exception. Accordingly, sunflower microgreens are typically harvested within 7 days of cultivation, making them ideal for mass production. The use of LED technology in the cultivation of microgreens offers the opportunity to further enhance their nutritional value and therapeutic potential. This review provides an overview of the benefits of sunflowers, sunflower microgreens, pre-treatments, and the ideal harvest period. The potential improvements from LED lighting are discussed and its impact on human health is explained.

Effects of Hormonal Regulation on Cell Number and Cell Size in Determining Fruit Size: A Mini-Review

Siti Khadijah A Karim — 2024-11-30

Fruits are sold by weight, and hence, fruit size is a central indicator of fruit yield and quality. In horticultural industries, fruit growers and researchers continually search for and improve cultivation methods to enhance fruit size. By providing a fundamental understanding of how fruit size is regulated in plants, the process of cell number production followed by the increase of cell size has been widely studied. Molecular and cellular approaches provide direction to both scientists and breeders in fruit quality enhancement. This mini-review discussed the interplay among major plant hormones in regulating cell number production and cell size in horticultural plants. We focused on hormones that are mainly involved in determining cell proliferation and cell size and on their interaction during genetic regulation and their signaling pathways, which in turn, influence final fruit size. We also deliberated the current findings around this research niche at cellular and molecular levels. This will ultimately assist breeders in improving the fruit quality, and yield and increase profit.

Enhanced Growth Performance and Steviol Glycosides Content in Stevia Rebaudiana Under Elevated Carbon Dioxide

A Abzar — 2024-11-30

In the current climate-changing scenario with a steadily rising CO₂ concentration, there is a chance that crop performance will be affected in terms of growth, yield, and quality. Therefore, an experiment was conducted in a glasshouse using a randomized complete block design with four replications to investigate the effect of short and long-term elevated CO₂ on growth performance and chemical markers of Stevia rebaudiana Bertoni. The CO₂ in the glasshouse was gradually elevated from 400 ppm to 1800 ppm weekly. The plants were exposed to elevated CO₂ for four months (T1), two months (T2), and one month (T3), while the control plants (T4) were grown under ambient CO₂ (aCO₂) levels to assess the effect of elevated atmospheric carbon dioxide (eCO₂) on stevia crop growth performance and steviol glycosides content. The number of branches per plant, plant height, number of leaves per branch, and plant biomass were found to be significantly increased under eCO₂ treatment over aCO₂ treatment. The eCO2 increased photosynthetic rate by 46% for T1, 45% for T2, and 29% for T3 over control plants (T4) at 3rd month of planting. The enhancement in photosynthesis is attributed to an increase in stevioside; with a 33% increase for T1 28.83% for T2 and 11% for T3 over aCO₂. Similarly, the rebaudiosides A were also significantly increased by 32.8% for T1, 25% for T2, and 15% for T3 compared to the control under aCO₂. Based on our findings, we concluded that eCO₂ levels positively influenced the growth, biomass, and glycoside content by enhancing the physiological performance of Stevia rebaudiana Bertoni.

Effect of Auxins on Growth Enhancement of Cell Suspension Culture of Tongkat Ali Hitam (Polyalthia bullata)

Nurul Farhana Farezol — 2024-11-30

Polyalthia bullata, a Southeast Asian plant, is valued for its bioactive compounds with pharmaceutical potential. To prevent overharvesting and extinction, cell suspension culture offers a sustainable method for the mass production of these compounds. Despite its effectiveness, no studies on Polyalthia bullata cell suspension culture have been established. Therefore, this study aimed to establish the culture by evaluating growth and biomass production. To achieve the objective, leaf derived callus of Polyalthia bullata was multiplied on Murashige and Skoog (MS) + 30 µM dicamba medium. Subsequently, cell suspension initiation and multiplication were carried out using half-strength MS basal medium (½ MSO) supplemented with 5, 15, 25, and 30 µM of 1-naphthaleneacetic acid (NAA), indole-3-acetic acid (IAA), and indole-3-butyric acid (IBA), respectively. In this study, suspension cells in the ½ MSO recorded the highest increment in fresh (4.455 ± 1.170 g FW) and dry weight (0.220 ± 0.033 g DW) but produced dark brown cells. Meanwhile, cells grown on ½ MS medium supplemented with 30 µM NAA recorded the highest increase in fresh weight (3.472 ± 0.694 g FW) and dry weight (0.190 ± 0.012 g DW), displaying a light yellowish-brown cell. Although the ½ MSO yielded the highest biomass, the cell suspension cultures supplemented with 30 µM NAA showed promising results, achieving higher biomass compared to other auxin treatments and exhibiting a light yellowish-brown cell. This suggests that 30 µM NAA is a more efficient auxin utilization in reducing the occurrence of dark brown cells. In conclusion, optimizing auxin concentrations is crucial for high-quality Polyalthia bullata cell suspension culture. This study can provide insight into sustainable cultivation practices for the plant, serving as a potential bio-factory for mass-producing bioactive compounds.

Evaluation of Environmental Parameters and Economic Efficiency of Integrated Farming System on Acidic Soil and Saltwater Intrusion in The Coastal Area: A Case Study of Mekong Delta, Vietnam

Vo Van Ha — 2024-11-30

The shift to growing sedge plants, combining raising snails and tilapia in coastal areas could improve the soil nutritional environment, income, and land use efficiency compared to rice monoculture. This study aims to evaluate soil and water environmental factors and to compare the financial efficiency of integrated farming with rice monoculture farming. These experiments were arranged on field land affected by drought and saltwater intrusion in two ecological regions of Kien Giang province. The research found the adaptation of crops (rice, sedge) and aquatic species (snails, tilapia) to the characteristics of acidic and saline soils in coastal areas. The results showed that an integrated farming system reduced soil salinity, but increased soil pH, nitrogen, phosphorus, potassium, and organic matter content more than rice monoculture farming. In addition, this system improved pH, reducing salinity, temperature, and TDS of water more than rice monoculture farming. Acidity and salinity factors affect the rice yield of Winter-Spring crops. The sedge grass (Cyperus malaccensis) grew well under the pH and salinity conditions, but the sedge yield in the dry season was higher than in the rainy season. The weight gain of tilapia (Oreochromis niloticus) was from 0.45 to 0.96 g/day, but fish yield was still low (226 - 541 kg/ha); due to low survival rate (30-36%). Snails (Pila gracilis) adapted well to experimental conditions and the survival rate reached 53-79%. The data analysis of financial efficiency showed that the profit of integrated farming was higher than rice monoculture farming (10,905 to 11,146 USD compared to 904-1,672 USD/ha/year). Therefore, diversified land use in coastal areas to grow sedge grass combined with snails and tilapia increased household income in these study sites.

Three Isolate of Actinomycetes As Biological Control Against Magnaporthe orzyae and Fusarium solani

Aisyah Fatiha Zailan — 2024-11-30

Phytopathogens are causing global food security concerns, resulting in approximately 12.5% crop loss. These fungi significantly impact plant physiology, growth, and development. Traditional fungicides used for control are known to be harmful to both humans and the environment. Therefore, this study advocates an eco-friendly approach using biological control agents to curb phytopathogenic fungi growth. This research focuses on identifying potential antagonistic microorganisms capable of inhibiting two common phytopathogenic fungi: Magnaporthe oryzae, responsible for rice blast disease, and Fusarium solani, causing Fusarium wilt disease. The inhibitory strength of the microorganisms isolated from six different locations in Peninsula Malaysia was tested in vitro via dual culture assays. Our findings revealed three actinomycete species isolated from Bangi Forest Reserve, UKM, namely Streptomyces morookaense UKM1, Streptomyces rubrisoli UKM1, and Streptomyces gelaticus UKM1 exhibit a remarkable ability to inhibit the growth of both M. oryzae and F. solani, with a percentage inhibition radial growth (PIRG) exceeding 70%. Additionally, distinct differences in pathogens mycelia were observed after being grown together with the antagonistic microorganisms. In summary, our research identifies promising microorganisms with potent inhibition capabilities against multiple plant pathogens, offering potential solutions for sustainable agriculture and improved food security.

Enhanced Rice (Oryza sativa L.) Plant Growth and Nutrient Contents During The Vegetative Stage Through Zinc Solubilizing Bacterial Bead Inoculation

Irsyad Sulaimi Ramly — 2024-11-30

Zinc-solubilizing bacteria (ZSB) can increase zinc bioavailability in soil and transform insoluble zinc into an accessible form, which helps reduce crop zinc deficiencies, simultaneously improving soil fertility and crop nutrition. The effects of two ZSB strains, Acinetobacter nosocomialis (SR R-10) and Acinetobacter seifertii (SR-12) were evaluated in the present study on the rice plant growth and nutrient contents using the bead inoculation method. A completely randomized design (CRD) was employed and four treatments were applied: 1) non-inoculated (control), 2) SR R-10 strain, 3) SR R-12 strain, and 4) mixed inoculation of SR R-10 and SR R-12 strains. After 40 days of sowing, the growth parameters were measured. The results revealed that SR R-10 inoculant enhanced the growth by producing the tallest plant (63.47 ± 1.87 cm) and longest root (19.93 ± 0.48 cm). SR R-10-treated plants also showed the highest leaf count (32 ± 0.58 leaves) and Soil Plant Analysis Development (SPAD) value (32.67 ± 1.59). The mixed inoculant showed synergistic benefits, indicated by the higher plant height, SPAD reading, and leaf count, compared to the non-inoculated treatment. SR R-10 and mixed inoculant increased plant biomass, measuring 4.67 ± 0.30 g and 4.40 ± 0.28 g, respectively, compared to non-inoculated plants (3.19 ± 0.17 g). For nutrient content, plants with SR R-10 inoculation showed the highest concentration of nitrogen (2.24 ± 0.00%), phosphorus (0.24 ± 0.00%), potassium (2.79 ± 0.03%), and zinc (59.51 ± 2.69 mg kg^-1). Mixed inoculant also improved soil fertility by increasing the available Zn (6.17 mg kg-1) in the soil, however, it lowered the soil pH to pH 5.8. These findings highlight the potential of ZSB, particularly A. nosocomialis (SR R-10), to improve rice plant’s growth and nutritional quality and increase the bioavailability of zinc in the soil to promote sustainable agricultural practices.

Ultrasonic-Assisted Extraction of Phenolic Compound From Harumanis Mango Leaves (Mangifera indica) Using Green Natural Deep Eutectic Solvents (NADESs)

Ahmad Mukhlis Abdul Rahman — 2024-11-30

Harumanis mangoes, known for their taste and nutrition, are a symbol of Perlis, Malaysia. Natural Deep Eutectic Solvents (NADESs) are being studied for eco-friendly extraction methods. There is limited information on green extraction from Harumanis mango leaves, and NADESs have not been used for this purpose. This study aims to evaluate the green extraction of phenolic compounds from Harumanis mango leaves using five NADESs systems, assess the phytochemical composition, and test their antimicrobial potential. These NADESs were prepared by heating and stirring their components until a clear solution was formed. The extraction yields of NADESs were compared with conventional solvents like 100% ethanol, 100% methanol, 50% ethanol, and 50% methanol for extracting phenolic compounds. The chosen NADES was processed with Ultrasonic Assisted Extraction (UAE). The total phenolic content (TPC) in the extracts was measured using a gallic acid standard curve and spectrophotometry. The extract with the highest TPC value from NADES extraction was evaluated for phytochemicals using FTIR and tested for antimicrobial activity with the disc diffusion method. Based on the screening of different NADESs, the highest phenolic content was recorded by lactic acid: glycerol system at 135.74 mg GAE g−1 dw. The lowest TPC value was recorded with sodium acetate: glycerol system, which was 32.76 mg GAE g⁻¹ dw. Among the conventional solvents, the highest TPC value was recorded by 50% ethanol at 133.09 mg GAE g⁻¹ dw, and the lowest TPC value was by 100% ethanol at 67.18 mg GAE g⁻¹ dw. The use of UAE with lactic acid: glycerol NADES system yields the highest TPC value of 142.87 mg GAE g⁻¹ dw. Harumanis extract using NADES-3 had saponins, phenols, glycosides, tannins, and antimicrobial activity on gram-positive and gram-negative bacteria. The results show that NADES effectively extracts phenolic compounds from Harumanis leaves, which have significant therapeutic potential.

Effects of Sub1 and qDTY on The Agro-Morpho-Physiological Traits of Rice (Oryza sativa L.) Under Reproductive Stage Drought Stress

Shakirah Mohammad Nahar — 2024-11-30

Drought is one of the major abiotic stresses that affects plants at various levels and stages as it also reduces crop productivity and weakens global food security. Breeding and screening of drought tolerant varieties are crucial to ensure the continuity of food supply. Two breeding lines, UKM-112 and UKM-114 with QTL(s) for submergence tolerance (Submergence 1 [Sub1]) and yield under drought stress (qDTY) and together with their recurrent parental line, UKM-5, and a drought-sensitive cultivar, MR219 were screened for their agro-morpho-physiological responses under reproductive stage drought stress (RS) and non-stress (NS) to determine how the Sub1 interacts with qDTY in enhancing drought tolerance. Under NS, UKM-112 (with qDTY_3.1 and Sub1) recorded the highest values while MR219 (no QTL) recorded the lowest values for most parameters. Furthermore, lines with QTL (either single or two QTLs) outperformed MR219 in all agronomic parameters including grain yield (GY) under RS. UKM-114, which carries the Sub1, demonstrated higher values for important agronomic traits such as the number of filled spikelets (FS), thousand-grain weight (TGW), and GY when exposed to drought stress. The enhanced values in UKM-114 are a good indication that the presence of Sub1 minimized the negative impacts of drought on yield-related traits. The genotype with qDTY or a combination of qDTY and Sub1 has a lower photosynthetic rate under RS compared to the genotype with only Sub1 but higher than MR219 suggesting that qDTY improved the photosynthetic rate, though lesser compared to Sub1. These results indicate that Sub1+qDTY does not effectively improve drought stress survivability and yield. The presence of qDTY appears to mask the beneficial effect of Sub1 in improving photosynthetic rate and yield. While the present study did not report a positive outcome for Sub1+qDTY, the combination of these traits has the potential to provide beneficial effects without any negative interactions.

Genomic Analysis And Synergistic Biocontrol Potential of Bacillus thuringiensis MPOB Bt1 With Flubendiamide Against Oil Palm Bagworm, Metisa plana Walker (Lepidoptera: Psychidae)

Mohd Shawal Thakib Maidin — 2024-11-30

Bacillus thuringiensis MPOB Bt1 (MPOB Bt1) is a biological control agent used to suppress bagworm larvae in Malaysian oil palm plantations. Although MPOB Bt1 has been utilized in the field for biocontrol of oil palm bagworm larvae, its genetic basis for biocontrol capabilities and the combined effectiveness of MPOB Bt1 with flubendiamide have not been fully investigated. This study aimed to provide a genomic foundation for understanding the insecticidal properties of MPOB Bt1 by identifying specific genes that may be responsible for its biological activity. In addition, the study focused on evaluating the practical biological efficacy of MPOB Bt1, both alone and in combination with flubendiamide, against Metisa plana. The draft genome sequence of MPOB Bt1 was determined using Illumina HiSeq and PacBio platforms. The genome size was 6.9 Mb, with a GC content of 35.1%, and containing 5,558 coding DNA sequences, which included Cry9Ea, Cry1Ab, Cry1Ca, and Cry1Da of δ-endotoxin genes, 23 rRNAs, and 86 tRNAs. Bioassays showed that MPOB Bt1 exhibited toxicity to oil palm bagworm larvae, with an LC50 of 3.31 × 10¹⁰ spores/mL after 72 hr of treatment. The combination of MPOB Bt1 and flubendiamide showed a synergistic effect (LC₅₀ of 1.19 × 10⁹ spores/mL), with a ratio of experimentally observed efficacy to predicted efficacy greater than one. This study presents the draft genome sequence of MPOB Bt1 and identifies multiple insecticidal genes that potentially exhibit inhibitory effects against M. plana larvae. The toxicity and synergistic effect of MPOB Bt1 and Fbd suggest a potential strategy for controlling bagworm infestation in oil palm plantations. These findings provide a promising safer alternative to chemical insecticides for sustainable M. plana management in oil palm plantations.

The Evaluation of Blast Resistance and Submergence Tolerance of New Breeding Rice (Oryza sativa L.) Lines Developed Through 4-Way Marker-Assisted Breeding

Selvia Dewi Pohan Pohan — 2024-11-30

This study aimed to create new rice lines with a strong resistance to blast disease and a high tolerance to submergence. This was achieved by introducing Pi and Sub1 QTLs into the popular local rice variety, Pulau Batu using a 4-way marker-assisted breeding technique. The progenies were evaluated both phenotypically and genotypically to identify those that have favorable traits. The 4-way-F3 rice breeding lines that showed exceptional performance were then assessed in both greenhouse and rice field nurseries from April to July 2023, corresponding to the dry season. The blast fungus, Magnaporthe oryzae (MoK19-28) isolated from a local rice field in West Sumatra was utilized as a fungal inoculum to assess the resistance level of established breeding lines against blast disease. Phenotypic blast resistance test was conducted according to the SES-blast-test standard. Consequently, a submergence tolerance test was carried out to assess the tolerance level of breeding lines to submergence over 14 days of vegetative development, following the submergence tolerance test standard. The results indicated that 11 breeding lines exhibited exceptional performance when exposed to blast disease and submergence stress. Blast resistance test showed that 60% of the breeding lines were categorized as resistant, 27% as moderately resistant, and 13% as susceptible. The submergence test indicated that 7% of the breeding lines were categorized as tolerant, 42% as moderately tolerant, 28% as moderately susceptible, and 23% as highly susceptible. Plants with a high survival rate (>70%) tend to have a low elongation percentage rate (<30%) and low changes in chlorophyll content (<30%). In the natural nursery, they exhibited superior performance in comparison to their parental lines, namely Pulau Batu, Inpari 48 Blas, and IR64-Sub1. This study proposed that the selected breeding lines combined Pi and Sub1A QTLs, which enhance phenotypic traits related to blast disease and submergence stress.

Sustainable Protocols For Leaf Sample Collection in In-Vitro Culture: Evaluating The Impact of Sample Bags and Hydrogen Peroxide Pre-Sterilization

Nursuria Md Setamam — 2024-11-30

This study investigates sustainable leaf sample collection protocols for in-vitro culture (IVC) of chili (Capsicum frutescens) and tomato (Solanum lycopersicum) leaves. The research aimed to enhance viability and reduce contamination of leaf explants by evaluating various types of sample bags and different concentrations of hydrogen peroxide (H₂O₂) pre-sterilization. Specifically, the study compared the effectiveness of normal sealed (NS) bags and vacuum-sealed (VS) bags, including high-action (VSH) and low-action (VSL) vacuum-sealed bags, alongside H₂O₂ pre-sterilization at various concentrations. Leaf samples were treated with ten different concentrations of H₂O₂(5% to 50%) to assess their impact on necrosis and surface contamination over 72 hr. Results showed that higher H₂O₂concentrations (above 30%) caused significant necrosis, while concentrations between 10% and 15% provided optimal pre-sterilization for both leaf types, effectively reducing contamination without excessive tissue damage. In the second phase, the research examined the influence of different sample bags on leaf explant sustainability. Vacuum-sealed bags, particularly those with low-action vacuum (VSL), significantly improved leaf longevity and minimized contaminant emergence compared to normal sealed bags. Combined with 15% H₂O₂pre-sterilization, VSL bags performed best, maintaining leaf morphology and viability for extended periods. Statistical analyses confirmed the significant impact of sampling bag type and pre-sterilization on contamination levels, necrosis emergence, and leaf longevity. The findings suggest that using low-action vacuum-sealed bags (VSL) with 15% H₂O₂pre-sterilization is a promising approach for sustainable leaf sample collection, enhancing the success rate of IVC by minimizing microbial contamination and preserving leaf integrity during transport. This optimized protocol offers valuable insights for researchers and practitioners in plant tissue culture and agriculture, aiming to improve the sustainability and efficiency of leaf sample collection for in-vitro applications.