Grass Leaf Research Articles

Metabolite profile analysis of methanol extract of belulang grass (Eleusine indica (L.) GAERTN) leaves by gas chromatography-mass spectrophotometry (GC-MS) method

Leaf of belulang grass (Eleusine indica (L.) Gaertn) is one of the wild plants that is used as herbal medicine by the community because of its many health benefits for the treatment of certain diseases such as diabetes, high blood pressure, and cholesterol. A materil is said to have potential as a medicine because the composition of the chemical compounds contained in a plant is not always the same and requires further testing. Differences in chemical compound content can be influenced by environmental factors and plant metabolism. The aim of this research is to analyze the metabolite profile and abundance of metabolite compounds using the GC-MS instrument analysis approach. Sampling was conducted in Sidomulyo Village, Air Kumbang District, Banyuasin Regency, South Sumatra. Samples of belulang grass leaves obtained were dried, pulverized, and extracted with methanol solvent. The methanol extract was analyzed using GC-MS. The results showed that the highest 20 compound peaks were obtained based on the relative area percent of the 69 compounds obtained with an abundance of compounds amounting to 80.86%. At the highest peak, the compounds n-hexadecanoic acid, I-(+)-ascorbic acid 2, 6- dihexadecanoate, and pentadecanoic acid were found with a percent area of 31.25%.

Influence of different plant growth retardants in Mexican lawn grass (Zoysia matrella) for reducing the mowing frequency and better visual qualities

Mexican lawn grass (Zoysia matrella) is a perennial mat-forming species suited for the landscaping industry due to its versatile adaptability. The pleasing appearance of the lawn grasses can be achieved through mowing at regular intervals to avoid a shabby appearance, which requires skilled persons and ends up with expensive operation. Under these circumstances, the experiment was intended with the commonly available growth regulators for their efficiency in the reduction of the mowing cycle without losing or hampering their visual quality attributes. The application of 1.0% chlormequat chloride (T4) produced a mean grass leaf length of 2.00 cm, which was remarkably lower than that of control (T9), i.e., 4.87 cm. The same pattern of growth was exhibited during the 45th and 90th days after spraying. The mean turf shoot length (7.80 cm) and root length (13.40 cm) were observed in the control plots, while the application of 1.0% chlormequat chloride (T4) produced 3.83 cm and 7.94 cm, respectively, determining its ability to hamper the growth of turf grass. The Z. matrella grass failed to produce flower heads by the application of 1.0% mepiquat chloride (T2), 0.5% chlormequat chloride (T3), 1.0% chlormequat chloride (T4), 0.5% maleic hydrazide (T7) and 1.0% maleic hydrazide (T8). The control plots devoid of growth regulators initiate flower heads after 70 days. From the study, the application of 0.5% chlormequat chloride (T3) and 1.0% chlormequat chloride (T4) exerted a low level of thatch accumulation and no flower head formation was observed with maximal visual scoring, leading to the commercial expeditions for the turf industry.

17O-excess of grass leaf phytoliths across the North American prairies records late-growing season daytime relative humidity

Because it is an important climate parameter, an accurate proxy is required for the reconstruction of past Relative Humidity (RH). Triple oxygen isotopes of grass-leaf phytoliths have a high potential for this purpose. A strong correlation between RH and 17O-excess of grass leaf phytoliths has been previously demonstrated from calibration experiments in growth chambers and at natural Sub-Saharan African and Mediterranean sites. Here we focus on the potential of 17O-excess of grass leaf phytoliths as a proxy of RH across the North American Great Plains. We tested the relationship between the 17O-excess of naturally grown Calamovilfa longifolia phytoliths and RH for different periods of the grass growing season. The results show that 17O-excess of leaf phytoliths has a strong correlation with late-growing season (July–August) daytime RH, which varies from 29 to 72 % across North America. The correlation can be expressed as: 17O-excessleaf phytoliths = 4.14(±0.47) × RH (%) – 497(±26) (R2 = 0.85, p-value<0.0001), which is statistically equal to the previous calibration equation (Alexandre et al., 2018; Outrequin et al., 2021). To use the 17O-excess of bulk phytoliths from buried soils and sediments as a quantitative proxy of past RH, future calibration studies on soil phytoliths are needed to evaluate the contribution of non-transpiring phytoliths. The 17O-excess of stem water, which was determined by 17O-excess of stem phytoliths, shows similar values to the 17O-excess of precipitation in North America without evaporation, which therefore does not affect the 17O-excess of leaf phytoliths in North America. These results demonstrate that the 17O-excess of phytoliths is a promising proxy for regional growing season RH.

Effects of Edible Grass (Rumex patientia L. × Rumex tianschanicus A. LOS) Leaf Powder on Growth Performance, Antioxidant Properties, Cecal Short-Chain Fatty Acids, and Microbial Community Levels in Broilers.

The hybrid plant edible grass (Rumex patientia L. × Rumex tianschanicus A. LOS), a member of the Rumex genus, presents a novel food source with a protein content of approximately 30-40%. By incorporating non-traditional feed sources, such as edible grass leaf powder (EGLP), into broiler production, costs could be reduced. The experimental subjects of this study were Arbor Acres (AA) broilers. A total of 300 newly hatched broilers were randomly divided into to five groups, with each group consisting of six cages, housing 10 birds per cage. The control group was fed a basal diet composed of maize and soybean meal. In the experimental groups, varying percentages (3%, 6%, 9%, and 12%) of EGLP were substituted for the corn-soybean meal in the basal diet. In the diet, for days 1-21, the corn content was reduced from 1.90% to 8.20%, and the soybean meal content was lowered from 1.50% to 6.00%. Similarly, in the diet, for days 22-42, the corn content was decreased from 1.17% to 7.00%, while the soybean meal content was reduced by 1.50% to 6.00%. The experiment lasted 42 days and was divided into two phases: the brooding phase (days 1 to 21) and the finishing phase (days 22 to 42). The results show that substituting 3% and 6% EGLP for corn and soybean meal significantly increased the average daily gain (ADG) during the brooding period compared to the control group (p < 0.01). Additionally, the group with a 3% substitution rate exhibited a significant increase in the average daily feed intake (ADFI) during the brooding phase (p < 0.01). Throughout the 42-day experiment, substituting 3% and 6% of EGLP for maize and soybean meal did not significantly affect the overall growth performance of broilers (p > 0.05). However, a 6% supplementation notably reduced the feed conversion ratio (FCR) (p < 0.01). Both the 3% (EG3) EGLP and 6% (EG6) EGLP replacement meals significantly enhanced the antioxidant capacity of broiler chickens, as indicated by the increased levels of the total antioxidant capacity (T-AOC), superoxide dismutase (SOD), and glutathione peroxidase (GSH-Px) (p < 0.01). Additionally, broilers supplemented with 3-12% showed a marked increase in cecal short-chain fatty acids (SCFAs) compared to the control group (p < 0.01). The 3% EGLP replacement diet also significantly boosted the prevalence of Lactobacillus in the cecum (p < 0.01). Furthermore, after EGLP supplementation, there was a higher abundance of SCFA-metabolizing bacteria, particularly Alistipes and Christensenellaceae_R-7, compared to pre-treatment (p < 0.05). The prevalence of Clostridium was significantly greater in the groups receiving 9% and 12% EGLP (p < 0.05), while Butyrivibrio levels were notably higher after supplementation with 12% EGLP (p < 0.05).

IMPACT OF PROCESSED CYMBOPOGON CITRATUS (LEMON GRASS) LEAF MEAL ON GROWTH PERFORMANCE AND HAEMATOLOGICAL INDICES OF BROILER CHICKENS

The experiment was carried out to determine the impact of processed lemon grass (Cymbopogon citrates) leaf meal on the growth performance and haematological indices of broiler birds. One hundred and twenty (120), day old "Agrited" broiler chicks were randomly distributed into four treatment groups, each replicated three times with ten birds per replicate in a completely randomized design (CRD). Four diets were formulated such that the lemon grass leaf meal was incorporated into the diets at 0%, 0.75%, 1.50% and 2.25% corresponding to treatments 1, 2, 3 and 4 respectively. Feed and water were given ad-libitum throughout the experimental period of 49 days. Final body weight was superior (P&lt;0.05) in T4 (2530g), while the least value of 2200g was observed in treatment 1. Body weight gain was highest in T4 (1290g), but least in T1 (958g). While feed conversion ratio was at its best in treatment 4 with 1.99. Haematological profile results showed that there was no significant (P&gt;0.05) effect of lemon grass leaf meal across the treatment groups studied in terms of haemoglobin and red blood cell, but differed (P&lt;0.05) in packed cell volume and white blood cell. From the results obtained in this present research, it can be concluded that lemon grass leaf meal can be added up to 2.25% in the diet of broiler chickens without any undesirable effect in terms of growth performance and no negative impact on the health of the birds at this phase of growth.

Efficacy of biocontrol-agents and plant extracts against Sclerotinia sclerotiorum causing stem rot of chickpea

The present study was conducted to evaluate biocontrol-agents, including Trichoderma viride, T. harzianum and Pseudomonas fluorescens and plant extracts, Ginger, Garlic, Tulsi, Lemon grass and Neem against Sclerotinia sclerotiorum (ON831560.1) under in vitro condition. All the biocontrol-agents suppressed the mycelial growth of S. sclerotiorum. Maximum suppression (69.29%) was observed with T. harzianum, followed by T. viride, which was on par with each other. The Pseudomonas fluorescens was observed to have minimum suppression (61.51%) but more than the control. Among the plant extracts maximum percent inhibition of the pathogenic fungus was observed in treatment with Neem leaf extract (42.58%), followed by garlic clove extract, ginger rhizome extract, and lemon grass leaf, while the minimum per cent inhibition was observed in Tulsi leaf extract (12.30%).

Development of a Reference Transcriptome and Identification of Differentially Expressed Genes Linked to Salt Stress in Salt Marsh Grass (Sporobolus alterniflorus) along Delaware Coastal Regions.

Salt marsh grass (Sporobolus alterniflorus) plays a crucial role in Delaware coastal regions by serving as a physical barrier between land and water along the inland bays and beaches. This vegetation helps to stabilize the shoreline and prevent erosion, protecting the land from the powerful forces of the waves and tides. In addition to providing a physical barrier, salt marsh grass is responsible for filtering nutrients in the water, offering an environment for aquatic species and presenting a focal point of study for high salt tolerance in plants. As seawater concentrations vary along the Delaware coast from low to medium to high salinity, our study seeks to identify the impact of salt tolerance in marsh grass and to identify genes associated with salt tolerance levels. We developed more than 211,000 next-generation-sequencing (Illumina) transcriptomic reads to create a reference transcriptome from low-, medium-, and high-salinity marsh grass leaf samples collected from the Delaware coastline. Contiguous sequences were annotated based on a homology search using BLASTX against rice (Oryza sativa), foxtail millet (Setaria italica), and non-redundant species within the Viridiplantae database. Additionally, we identified differentially expressed genes related to salinity stress as candidates for salt stress qPCR analysis. The data generated from this study may help to elucidate the genetic signatures and physiological responses of plants to salinity stress, thereby offering valuable insight into the use of innovative approaches for gene expression studies in crops that are less salt tolerant.

Identification of Bioactive Secondary Metabolites in Citronella Grass Leaves (Cymbopogon nardus L.) against Curvularia andropogonis

Citronella grass (Cymbopogon nardus) is an essential oil-producing plant. The essential oils consist of geraniol and citroneal whose production is affected by plant health. The production of citronella grass decreases (harvest loss) due to red spot disease caused by Curvulaia andropogonis infection which also affects the bioactive composition of secondary metabolites. Defense signal responses are also generated using plant defense pathways which result in compounds used for counterattacking plant invasions. The purpose of this study was to determine the secondary metabolites of C. nardus attacked by C. andropogonis. This research used HPLC to analysis citronellol and geraniol C. nardus with normal, wound and infected treatment. The Gas Chromatography-Mass Spectrometry (GCMS) method was used to detect metabolites profiles in normal treatment, injury, and infection, and then analyzed based on metabolite groups and metabolic pathways. The result of this study indicated that the citronellol in normal treatment sample was higher, namely 102.003mg/L compared to the wound treatment, which was 100.120mg/L and the infected treatment, which was 89.356mg/L. Likewise for geraniol in the normal treatment of 20.065mg/L, which is greater than the wound treatment, which was 19.245 mg/L and the infected, which was 15.765mg/L. There were 12 types of metabolites based on chemical grouping including alkaloids, carboxylic acids, fatty acids, flavonoids, nucleic acids, phenolics, terpenoids, alcohols, aldehydes, amino acids, heterocyclic compounds, and carbohydrates. The highest metabolites were found in carboxylic acid. Metabolic pathways resulted carboxylic acids which came from 2-Oxocaboxylic acid metabolism, and phenolics came from the biosynthesis of secondary metabolites, which were highest in carbohydrate metabolism. In conclusion, almost all metabolites and metabolic pathways increase in the infection treatment which was significant with the results of citronellol and geranioldecreased so that the overall content of bioactive secondary metabolites decreased.

Impacts of grazing management strategies on forage canopy structure in multi-species pastures during the wet-dry transition period

The condition of pastures during the wet-dry transition period reduces livestock production since there is an increase in dead material and a reduction in green tissues. This study evaluated the influence of grazing management strategies on the structure of the forage canopy during the wet-dry transition period. The pastures were composed of Aruana guineagrass (Megathyrsus maximum Syn. Panicum maximum cv. Aruana) and three legumes: Macrotyloma (Macrotyloma axillare), Calopo (Calopogoinum mucunoides), and Stylo (Stylosanthes macrocephala + Stylosanthes capitata). The treatments corresponded to four forage canopy heights (15, 30, 45, and 60 cm), and the grazing management strategies involved steady or variable stocking rates with sheep. The experiment was conducted in a randomized complete block design with four replications totaling 16 experimental units (paddocks). The masses of grass leaf blades and stems were higher at heights of 45 and 60 cm (P = 0.002), while the proportion of dead material was smaller in these than in the short pastures (15 and 30 cm) (P = 0.0497). There was an increase in the proportion of dead material over the dry-water transition period. The presence of grass and legume leaves was higher in the upper stratum of tall pastures (45 and 60 cm) and the proportion of legumes did not differ between grazing management strategies (P &gt; 0.05). These strategies were represented by canopy heights of 45 to 60 cm and showed more leaf mass, less dead material, and better pasture structure, so these parameters can be used during the wet-dry transition period.

Growth Performance and Haematological Profile of Broiler Chickens Fed Graded Levels of Lemon Grass Leaf Meal

Growth Performance and Haematological Profile of Broiler Chickens Fed Graded Levels of Lemon Grass Leaf Meal

Combined effects of fire and drought are not sufficient to slow shrub encroachment in tallgrass prairie.

Woody encroachment-the spread of woody vegetation in open ecosystems-is a common threat to grasslands worldwide. Reversing encroachment can be exceedingly difficult once shrubs become established, particularly clonal species that resprout following disturbance. Single stressors are unlikely to reverse woody encroachment, but using multiple stressors in tandem could be successful in slowing or reversing encroachment. We explored whether increasing fire frequency in conjunction with multi-year drought could reduce growth and survival of encroaching shrubs in a tallgrass prairie in northeastern Kansas, USA. Passive rainout shelters (~ 50% rainfall reduction) were constructed over mature clonal shrubs (Cornus drummondii) and co-existing C4 grasses in two fire treatments (1-year and 4-year burn frequency). Leaf- and whole-plant level physiological responses to drought and fire frequency were monitored in shrubs and grasses from 2019 to 2022. Shrub biomass and stem density following fire were unaffected by five years of consecutive drought treatment, regardless of fire frequency. The drought treatment had more negative effects on grass leaf water potential and photosynthetic rates compared to shrubs. Shrub photosynthetic rates were remarkably stable across each growing season. Overall, we found that five consecutive years of moderate drought in combination with fire was not sufficient to reduce biomass production or stem density in an encroaching clonal shrub (C. drummondii). These results suggest that moderate but chronic press-drought events do not sufficiently stress encroaching clonal shrubs to negatively impact their resilience following fire events, even when fire frequency is high.

Extraction, physicochemical and structural characterisation of palm grass leaf fibres for sustainable and cleaner production of textile and allied cellulosic applications

Natural fibres are in great demand as a clean and green material as reinforcement in sustainable and environment-friendly biodegradable composites. The study aimed to extract palm grass leaf fibres through water retting, a cleaner and greener approach compared with the use of 5–10% NaOH. The physicochemical characterisation was done by SEM, optical microscopy, FT-IR, XRD, TGA, bundle strength, moisture content and standard biochemical tests for cellulose, hemicellulose, lignin and ash. New natural fibres extracted from Curculigo capitulata by water retting showed a smooth surface of uniaxial fibres under SEM and optical microscope compared to eroded surfaces of chemically extracted fibres. Both the fibres extracted by water retting and with 5% NaOH showed nearly similar crystallinity index (84–85%) and size (2.44nm), whereas the former contained 64% cellulose with bundle strength 154MPa compared to 72% and 219.11MPa with the latter. While using 10% (NaOH) showed cellulose 82.29 ± 0.63%, crystallinity index 87.43%, and bundle strength 256.46 ± 15.81MPa. Approximately similar lignin content (20.30 ± 0.91–21.66 ± 1.18%) and mass degradation (%) were obtained in water-retted and 5%–7.5% NaOH extracted fibres. FT-IR spectra showed the characteristic bands at 3421cm−1 for O–H stretching and 2917cm−1 for alkyl C–H stretching in cellulose; at 1630cm1 for CC stretching in lignin. All the extracted fibres showed industrial potential similar to successful natural fibres for fine rope, yarn, handmade paper, and fabrics aiming for a circular bioeconomy.

Rare Earth Element Recovery and Hydrochar Evaluation from Hyperaccumulator by Acid Leaching and Microwave-Assisted Hydrothermal Carbonization

Phytomining is a sustainable approach that uses hyperaccumulators for critical element extraction from various substrates, such as contaminated soils, mine tailings, and aqueous solutions. In this study, grass seeds were fed with a solution containing Y, La, Ce, and Dy, resulting in around 510 mg/kg (dry basis) of total rare earth elements (TREEs) accumulated in grass leaves. Electron probe microanalyzer (EPMA) analysis showed that rare earth elements (REEs) in the grass leaves (GL) predominantly complexed with phosphorous (P). Around 95% of Y, 93% of La, 92% of Ce, and 93% of Dy were extracted from the GL using 0.5 mol/L H2SO4 at a solid concentration of 5 wt.%. Subsequently, microwave-assisted hydrothermal carbonization (MHTC) was used to convert the leaching residue into hydrochar to achieve a comprehensive utilization of GL biomass. The effect of temperature on the structural properties and chemical composition of the resulting hydrochar was evaluated. Scanning electron microscopy (SEM) analysis revealed that the original structure of GL was destroyed at 180 °C during MHTC, producing numerous microspheres and pores. As the reaction temperature increased, there was a concurrent increase in carbon content, a higher heating value (HHV), and energy densification, coupled with a decrease in the hydrogen and oxygen contents of hydrochar. The evolution of H/C and O/C ratios indicated that dehydration and decarboxylation occurred during MHTC. The results showed that the waste biomass of the GL after REE extraction can be effectively converted into energy-rich solid fuel and low-cost adsorbents via MHTC.

In-vitro and In Silico Assessment of Anti-inflammation Properties of Saponarin Extracted from Hordeum Vulgare.

Hordeum vulgare, commonly known as Barley grass, is a historically significant cultivated plant with profound implications for societies, agricultural sciences, and human nutrition. It has been valued for both sustenance and its potential medicinal properties. This study aims to comprehensively investigate the medicinal properties of Hordeum vulgare, focusing on its potential therapeutic benefits and anti-inflammatory properties. Additionally, we seek to quantify and compare the phytochemical content of two distinct extracts: Barley Grass Hexane Extract (BGHE) and Barley grass aqueous extract (BGAQ). We quantified the phytochemical contents of BGHE and BGAQ and evaluated their anti-inflammatory effects using UV spectroscopy at 560 nm, coupled with the RBC membrane stabilization technique. Subsequently, we conducted in silico studies to assess the in vitro anti-inflammatory potential of Barley grass leaf extracts. Both BGHE and BGAQ demonstrated significant inhibitory effects on inflammation compared to the control group. However, BGHE exhibited superior anti-inflammatory efficacy when compared to BGAQ, suggesting its role as a potential anti-inflammatory agent. In silico studies further supported the anti-inflammatory potential of Barley grass leaf extracts. Hordeum vulgare, or Barley grass, offers a wealth of health benefits, including anti-inflammatory, anti-diabetic, anti-cancer, antioxidant, anti-acne, and anti-depressant properties. These properties contribute to improved immunity, reduced cardiovascular disorders, and alleviation of fatigue. The distinct extracts, BGHE and BGAQ, both exhibit promising anti-inflammatory capabilities, but BGHE shows better anti-inflammatory activity. This research sheds light on the therapeutic potential of Barley grass, making it a valuable candidate for further exploration in the field of natural medicine.

Three-year field study on grass growth and soil hydrological properties in biochar-amended soil

Field monitoring was conducted to investigate and quantify the long-term effects of peanut shell biochar on soil-grass interaction over three years. Three 10 m × 5 m grassed plots were constructed in completely decomposed granitic soil. Two of them were amended, respectively, with 5% and 10% biochar contents (m3/m3) for grass growth, while the third was without biochar amendment. During the three-year monitoring, plant characteristics, saturated water permeability (ks) of grassed soil and soil suction were measured. The monitored results show that the grass leaf area index (LAI) and root length density (RLD) with biochar amendment were improved by 38% and 200%, respectively. In the grassed plot without biochar, a threshold RLD existed with a value of 1.7 cm/cm3, beyond which ks raised pronouncedly. The threshold RLD increased by 52% when biochar content increased from 0% to 10%. This implies that biochar may restrict the increase in ks of grassed soil due to the rise in the threshold RLD. The presence of biochar and grass can retain over 100% higher suction after heavy rainfalls, while 54% lower peak suction under evapotranspiration (ET) compared with the non-amended plot. Biochar can alleviate the negative effects on hydraulic properties caused by plant growth and reduce ET-induced excessive water loss. A 5% peanut shell biochar content is recommended for the long-term management of vegetated earthen infrastructures.

Allometries of cell and tissue anatomy and photosynthetic rate across leaves of C3 and C4 grasses.

Allometric relationships among the dimensions of leaves and their cells hold across diverse eudicotyledons, but have remained untested in the leaves of grasses. We hypothesised that geometric (proportional) allometries of cell sizes across tissues and of leaf dimensions would arise due to the coordination of cell development and that of cell functions such as water, nutrient and energy transport, and that cell sizes across tissues would be associated with light-saturated photosynthetic rate. We tested predictions across 27 globally distributed C3 and C4 grass species grown in a common garden. We found positive relationships among average cell sizes within and across tissues, and of cell sizes with leaf dimensions. Grass leaf anatomical allometries were similar to those of eudicots, with exceptions consistent with the fewer cell layers and narrower form of grass leaves, and the specialised roles of epidermis and bundle sheath in storage and leaf movement. Across species, mean cell sizes in each tissue were associated with light-saturated photosynthetic rate per leaf mass, supporting the functional coordination of cell sizes. These findings highlight the generality of evolutionary allometries within the grass lineage and their interlinkage with coordinated development and function.

Effects of Varying Levels of Lemon Grass Leaf Meal on Performance, Haematology and Serum Biochemical Indices of Broilers

A total of two hundred unsexed broiler chicks aged two weeks were used for six weeks feeding trial to evaluate growth performance, hematology, and serum biochemistry. In this study, broilers chicks were fed dietary lemon grass leaf meal at inclusion levels of T1control (0.00%), T2 (1.50%), T3 (2.25%) and T4 (3.75 %). The weighed broilers were distributed at random among the four treatment diets. A completely randomized experimental design was used, and each treatment was replicated five times with ten broilers per replicate. Experimental birds were provided experimental starter and finisher diets ad-libitum throughout the experimental period at weeks 2 to 4 and 5 to 7 respectively. The experiment revealed that weekly feed intake for week 2, 3, 4 and 6 was significantly affected (P&lt;0.05) except week five. The daily weight gain followed similar pattern, however significant difference were observed only in week 3, 4 and 7 in all the treatment groups. There were significant (P&lt;0.05) differences among the dietary groups in week 4, 6 and 7 in terms of feed conversion ratio. White blood cells value of birds fed on control diet 286.07x 109 /dl is similar to 283.37 and 268.67x 109 /dl for T3 and T4. Neutrophil values 14%, 19%,18% and 20% for T1, T2, T3 and T4 were statistically significant (P&lt;0.05) indicating that birds were challenged with increasing levels of lemon grass leaf meal beyond 3.75%. The results of this study indicate that birds fed with 1.5% of dietary lemon grass meal was the best among diets with lemon grass and comparable with the control group in terms of daily weight gain. This implies that birds fed with 1.5% level lemon grass leaf meal (LGLM) was able to utilize the experimental diet better than other treatment groups and without detrimental effects.

Antibacterial Activity of Several Types of Weed Extracts on The Growth of Escherichia coli

Escherichia coli is a type of Gram-negative bacteria that is commonly found in the human digestive tract. It has been reported as one of the bacteria that has been resistant to several antibiotics. This study aims to determine four (4) types of weed extracts that are considered but have not been used as antibacterial compounds against E. coli. This experimental study used a completely randomized design with several types of plant extracts, namely Acalypha indica L., Ageratum conyzoides, Phyllanthus niruri L., and Amaranthus spinosios at various concentrations (0, 50, and 100%). The results showed that the plant extract of A. indica L. had the ability as an antibacterial against the growth of E. coli at concentrations of 50% (1.41 ± 0.12) and 100% (1.53 ± 0.01) compared to other extracts. Meanwhile, the lowest average diameter of the inhibition zone for E. coli bacteria was found in the treatment of A. spinosios grass leaf extract 50% (1.17 ± 0.05).

ASSESSMENT OF THE ANTIFUNGAL ACTIVITY OF Cymbopogan citratus (Lemon grass) LEAF EXTRACT AGAINST SOME PHYTOPATHOGENS

Since the beginning of mankind, nature has been a source of medicinal agent for thousands of years. A plant pathogen is an infectious organism that is capable of causing disease to plants. This research work was aimed at assessing the antifungal activity of Cymbopogan citratus leaf extract on some phytopathogenic fungi isolated from agricultural soils. Aspergillus niger, Aspergillus tamari and Mucor circinelloides were isolated from an agricultural soil. Aspergillus tamari displayed highest susceptibility to the 50% ethanolic extract of the plant with a mycelial radial growth inhibition measurement of 18.25 ± 0.25 mm while Mucor circinelloides displayed the least susceptibility to the 100% ethanolic extract with a mycelial radial growth inhibition of 45.25 ± 0.25 mm. The results were significantly different from the controls (63.25 ± 0.75 mm, Aspergillus niger; 43.25 ± 1.25 mm, Aspergillus tamari and 63.75 ± 0.75 mm, Mucor circinelloides). In the same vein, the aqueous extract also displayed appreciable antifungal activity. The radial growth inhibition of the aqueous extract ranged from 24.25 ± 0.25 mm (25%, Mucor circinelloides) to 34.50 ± 0.50mm (100%, Aspergillus tamari). These were significantly different from the controls. This Study has shown that lemon grass leaf extract possesses antifungal activities to control phytopathogens, from the result obtained, it can be stated that lemon grass can be exploited as an alternative to chemical fungicides in combating resistance amongst phytopathogens.

Examination of the parameters controlling the triple oxygen isotope composition of grass leaf water and phytoliths at a Mediterranean site: a model–data approach

Abstract. Triple oxygen isotopes (17O-excess) of water are useful to trace evaporation at the soil–plant–atmosphere interface. The 17O-excess of plant silica, i.e., phytoliths, inherited from leaf water, was previously calibrated in growth chambers as a proxy of atmospheric relative humidity (RH). Here, using a model–data approach, we examine the parameters that control the triple oxygen isotope composition of bulk grass leaf water and phytoliths in natura, at the O3HP experimental platform located in the French Mediterranean area. A grass plot was equipped to measure for 1 year, all environmental and plant physiological parameters relevant for modeling the isotope composition of the grass leaf water. In particular, the triple oxygen and hydrogen isotope composition of atmospheric water vapor above the grass was measured continuously using a cavity ring-down spectrometer, and the grass leaf temperature was monitored at plot scale using an infrared (IR) radiometer. Grass leaves were collected in different seasons of the year and over a 24 h period in June. Grass leaf water was extracted by cryogenic vacuum distillation and analyzed by isotope ratio mass spectrometry (IRMS). Phytoliths were analyzed by IR–laser fluorination–IRMS after chemical extraction. We showed that the traditional Craig–Gordon steady-state model modified for grass leaves reliably predicts the triple oxygen isotope composition of leaf water during daytime but is sensitive to uncertainties on the leaf-to-air temperature difference. Deviations from isotope steady state at night are well represented in the triple oxygen isotope system and predictable by a non-steady-state model. The 17O-excess of phytoliths confirms the applicability of the 17O-excessphyto vs. RH equation established in previous growth chamber experiments. Further, it recorded average daytime RH over the growth period rather than daily RH, related to low transpiration and silicification during the night. This model–data approach highlights the utility of the triple oxygen isotope system to improve the understanding of water exchange at the soil–plant–atmosphere interface. The in natura experiment underlines the applicability of 17O-excess of phytoliths as a RH proxy.