Water Hyacinth Research Articles

Growth Dynamics and Nutrient Removal from Biogas Slurry Using Water Hyacinth

Aquatic macrophytes, notably the invasive water hyacinth, exhibit proficiency in nutrient removal from polluted water bodies, rendering them appealing for water remediation applications. This study investigates the potential of water hyacinth in phytoremediation, focusing on the effect of using nutrient-rich biogas slurry mixed with water in varying concentrations, i.e., 16.6, 33, 66.6, 100, and 133 mg/L for the investigation. The physiochemical properties of the liquid biogas slurry were evaluated before and after treatment with water hyacinth over eight weeks, with continuous monitoring of nutrient reduction rates. Results showcased substantial average reductions of nitrogen, phosphorus, and potassium, with a relative growth rate of 5.55%. The treatment also decreased pH, total dissolved solids, hardness, and chemical oxygen demand. The theoretical BMP of water hyacinth was determined using Buswell’s equation. Water hyacinth grown in the concentration of the biogas slurry exhibited the highest methane yield at 199 mL CH4/gm VS, along with the highest relative growth rate. This study used experimental data to create a mathematical model that describes how the relative growth of water hyacinth depends on the number of days and biogas slurry concentration (C). The model’s quality and effectiveness were evaluated using the goodness of fit (R2) and observable approaches. The polynomial model, referred to as Poly model 1, 2, is the best fit for describing the relationship between the growth percentage of water hyacinth, days, and nutrient solution concentration. In this model, C has a polynomial degree of one (normalized mean of 69.84 ± 43.54), while D has a degree of two (normalized mean of 30 ± 21.65).

Drivers of seasonal water hyacinth dynamics in permanently eutrophic estuarine waters

Anthropogenic nutrient enrichment is one of the key global change pressures threatening the health of estuaries. This is evident at the persistently eutrophic Swartkops Estuary located along the warm temperate coast of South Africa. Augmented nutrient-rich baseflows (e.g., stormwater runoff, wastewater treatment work discharges) have resulted in the persistent growth of invasive alien aquatic plants (IAAPs), particularly water hyacinth (Pontederia crassipes), in the upper estuarine reaches. As such, the objective of this study was to investigate the temporal population dynamics of water hyacinth in the Swartkops Estuary to inform management options. Methods included five-weekly sampling campaigns in winter, spring, and summer, interspersed with monthly sampling over a year-long period. Physico-chemical variables and river inflow were measured in situ, while samples were collected for inorganic nutrients, phytoplankton biomass, and IAAP measurements (cover, biomass, and tissue nutrients). Model results indicated that increased water temperature and inorganic nitrogen (ammonium and NOx) levels promoted increased coverage of water hyacinth, while seasonal analysis highlighted reduced (p < 0.05) dissolved oxygen levels during the peak summer IAAP accumulation period. Notably, model results indicated declining IAAP tissue TN and TP concentrations with increasing water temperature, yet overall TN and TP storage was highest in summer due to the extensive water hyacinth cover observed during this period. Overall, the proportionally low and transient nature of nutrient storage by water hyacinth populations, together with the detrimental consequences they facilitate, highlights the need to integrate short-term control measures with catchment-scale management interventions geared towards mitigating the causative drivers.

Natural biodegradable promising polymers from cellulose extracted from water hyacinth and seaweed for bioplastic production: A review

Natural biodegradable promising polymers from cellulose extracted from water hyacinth and seaweed for bioplastic production: A review

Physicochemical characteristics and oil sorption behaviours of novel polymeric materials based on modifications of water hyacinth (Eichhornia crassipes) fibres

Physicochemical characteristics and oil sorption behaviours of novel polymeric materials based on modifications of water hyacinth (Eichhornia crassipes) fibres

Effect of Varieties and Mulches on Field Performance of In Vitro Plantlets and Conventionally Propagated Potato Plants

Field performance of in vitro plantlets and conventionally propagated potato plants was observed. Five types of mulch viz. no mulch (control), black polythene, white polythene, straw and water hyacinth and six types of potato viz. Diamant conventional (conv.), Cardinal (conv.), Granola (conv.), Diamant plantlet (Plt.), plantlets of Cardinal and Granola were considered in this investigation. Significant effects of variety and mulch were found among the parameters studied. The highest (20.92 t ha-1) yield was recorded from Diamant, followed by Cardinal and the lowest (0.56 t ha-1) yield was obtained from Granola plantlet. Among the five different mulches, the highest (9.19) number of tubers hill-1 was harvested from straw mulch, whereas the lowest (7.35) number of tubers hill-1 was found in no mulch treatment. Straw mulch also gave the highest (10.97 t ha-1) yield than other treatments. The Chittagong Univ. J. B. Sci.,Vol. 7(1 &amp;2):21-34, 2012

A Feasibility Inquiry to the Sustainable Utilization of Few Invasive Flora

Objectives: The study focuses on utilising invasive flora affecting the indigenous plants and thereby bring about monetary benefits to the local people by means of handmade papers from the invasive weeds. Methods: Handmade paper from five invasive plants namely, Eichhornia crassipes, Eupatorium odorata, Combretum indicum, Lantana camara and Hyptis capitata was attempted. These plants after collection from Nilambur, Kerala were subjected to treatment with washing soda, blending, vat preparation, moulding and drying. This is followed by checking the paper quality parameters viz., Productivity, Clarity/opacity/transparency, Strength, Grammage, Paper grain, Ageing of paper and Moisture content. Findings: Out of the five invasive plants tested, the fibre yield was maximum for Eichhornia, but the productivity rate was less compared to other samples. Lantana and Hyptis yielded maximum productivity even though the fibre yield from these plants was less. The fibre uniformity of paper developed was positively detected for all the 4 plants except Eichhornia thereby proving the feasibility for paper manufacture. All sample paper allows the light; so, all are translucent in nature. Integrity of paper samples was retained in the paint test. The age test also yielded positive results. The gsm test showed lowest for Eichhornia as 98.12g/m2; Lantana 111.87g/m2; Combretum 131.87g/m2; Hyptis 163.75g/m2; Eupatorium is 255g/m2. Even though the gsm of Eichhornia is the best for paper manufacture according to gsm standards, the lack of fibre uniformity is a withdrawing feature for feasibility. The moisture content appeared high for Eichhornia and lowest for Combretum. Novelty: To date, studies on invasive plant utilisation done individually; no comparative study on productivity done. Current study can be further refined for environmental sustenance along with livelihood for local people. Keywords: Invasive Flora, Paper manufacture, Grammage test, Productivity, Ecological sustainability

Water hyacinths retain river plastics

Rivers represent one of the main conduits for the delivery of plastics to the sea, while also functioning as reservoirs for plastic retention. In tropical regions, rivers are exposed to both high levels of plastic pollution and invasion of water hyacinths. This aquatic plant forms dense patches at the river surface that drift due to winds and currents. Recent work suggests that water hyacinths play a crucial role in influencing plastic transport, by efficiently trapping the majority of surface plastic within their patches. However, a comprehensive understanding of the interaction between water hyacinths and plastics is still lacking. We hypothesize that the properties relevant to plastic transport change due to their trapping in water hyacinth patches. In particular, the length scale, defined as the characteristic size of the transported material, is a key property in understanding how materials move within rivers. Here, we show that water hyacinth patches trap on average 54%–77% of all observed surface plastics at the measurement site (Saigon river, Vietnam). Both temporally and spatially, we found that plastic and water hyacinth presence co-occur. The formation of plastic-plant aggregates carries significant implications for both clean-up and monitoring purposes, as these aggregates can be detected from space and need to be jointly removed. In addition, the length scale of trapped plastics (∼4.0 m) was found to be forty times larger than that of open water plastics (∼0.1 m). The implications of this increased length scale for plastic transport dynamics are yet to be fully understood, calling for further investigation into travel distances and trajectories. The effects of plastic trapping likely extend to other key properties of plastic-plant aggregates, such as effective buoyancy and mass. Given the prevalence of plant invasion and plastic pollution in rivers worldwide, this research offers valuable insights into the complex environmental challenges faced by numerous rivers.

Design of a sustainable system for wastewater treatment and generation of biofuels based on the biomass of the aquatic plant Eichhornia Crassipes

Colombia’s continuous contamination of water resources and the low alternatives to produce biofuels have affected the fulfillment of the objectives of sustainable development, deteriorating the environment and affecting the economic productivity of this country. Due to this reality, projects on environmental and economic sustainability, phytoremediation, and the production of biofuels such as ethanol and hydrogen were combined. The objective of this article was to design and develop a sustainable system for wastewater treatment and the generation of biofuels based on the biomass of the aquatic plant Eichhornia crassipes. A system that simulates an artificial wetland with live E. crassipes plants was designed and developed, removing organic matter contaminants; subsequently, and continuing the sustainability project, bioreactors were designed, adapted, and started up to produce bioethanol and biohydrogen with the hydrolyzed biomass used in the phytoremediation process, generating around 12 g/L of bioethanol and around 81 ml H2/g. The proposed research strategy suggests combining two sustainable methods, bioremediation and biofuel production, to preserve the natural beauty of water systems and their surroundings.

Haematological and Biochemical Responses of West African Dwarf Goats fed Water hyacinth and Cassava peel silage

The dry seasons in the tropics often result in a scarcity of green fodder, which can negatively impact ruminant animal production. As such, the utilization of aquatic plants, which are abundant poses a threat to aquatic organisms and waterways, may be explored as a means of mitigating this shortage. This study aimed to assess the suitability of water hyacinth and its implication on the blood profile of West African Dwarf (WAD) goats. A total of 20 West African Dwarf goats, aged 1-1.5 years and having liveweight of 11 ± 0.42 kg, were fed water hyacinth for a period of 70 days. A five-treatment and four-replicate completely randomized design was employed, in which water hyacinth replaced cassava peels at varying concentrations (0%, 15%, 30%, 45%, and 60%) in the formulated diets, with Panicum maximum and sundried poultry droppings added each at 20% to make complete diets. Significant differences (P&lt;0.05) were noted in the blood profile values of the experimental 6 -1 3 -1 animals (PCV:24.4-29.73%, RBC:7.75-13.8210 mm , WBC: 9.78-13.4810 mm ) and were within the normal ranges for healthy growing goats. Serum biochemical parameters obtained indicated that total protein (20.02g/L - 42.24g/L), albumin (11.40 – 25.00g/L), globulin (8.62 - 17.24g/L), and creatinine (1.00 - 2.13mg/dL), were significantly (P &lt; 0.05) different across the treatments. WBC and Lymphocytes values obtained were indicative of healthy immune system in the animals. Conclusively, supplementation of the WAD goat's diet with water hyacinth at a 15% inclusion level in cassava peels and poultry dropping silage was tolerable, presented optimal hematological and serum biochemical indices and did not pose any health risk to the experimental animals and was thereby recommended as a suitable feed for goats for optimum production, especially in extended dry seasons. Les saisons sèches sous les tropiques entraînent souvent une pénurie de fourrage vert, ce qui peut avoir un impact négatif sur la production animale de ruminants. Ainsi, l'utilisation de plantes aquatiques, dont l'abondance constitue une menace pour les organismes aquatiques et les cours d'eau, pourrait être explorée comme moyen d'atténuer cette pénurie. Cette étude visait à évaluer l'adéquation de la jacinthe d'eau et son implication sur le profil sanguin des chèvres West African Dwarf (WAD). Au total, 20 chèvres West African Dwarf, âgées de 1 à 1,5 ans et pesant 11 ± 0,42 kg, ont été nourries avec de la jacinthe d'eau pendant une période de 70 jours. Un plan complètement randomisé à cinq traitements et quatre répétitions a été utilisé, dans lequel la jacinthe d'eau a remplacé les pelures de manioc à des concentrations variables (0 %, 15 %, 30 %, 45 % et 60 %) dans les régimes alimentaires formulés, avec Panicum maximum et crottes de volailles séchées ajoutées chacune à raison de 20% pour constituer des régimes complets. Des différences significatives (P&lt; 0,05) ont été notées dans les valeurs du profil sanguin des animaux de laboratoire (PCV : 24,4-29,73 %, RBC : 7,75- 6 -1 3 -1 13,82x10 mm , WBC : 9,78-13,48x10 mm ) et se situaient dans les limites plages normales pour des chèvres en bonne santé. Les paramètres biochimiques sériques obtenus ont indiqué que les protéines totales (20,02 g/L - 42,24 g/L), l'albumine (11,40 – 25,00 g/L), la globuline (8,62 - 17,24 g/L) et la créatinine (1,00 - 2,13 mg/dL) , étaient significativement (P &lt; 0,05) différents selon les traitements. Les valeurs de leucocytes et de lymphocytes obtenues indiquaient un système immunitaire sain chez les animaux. En conclusion, la supplémentation du régime alimentaire de la chèvre WAD avec de la jacinthe d'eau à un niveau d'inclusion de 15 % dans les pelures de manioc et l'ensilage de volaille était tolérable, présentait des indices hématologiques et biochimiques sériques optimaux et ne posait aucun risque pour la santé des animaux de laboratoire et a donc été recommandée comme un aliment adapté aux chèvres pour une production optimale, notamment lors des saisons sèches prolongées.

Aquatic weed Eichhornia crassipes as sustainable feedstocks for biochar production: A potential of ammonium adsorption and kinetic models

The rapid emergence of unique types of pollutants is of worldwide concern owing to their deleterious effects on living beings. Mitigating pollution in the way of sustainability is the need of the hour to protect the existing environment from degradation. In this regard, eco-friendly biochar was prepared from the intact plant of Eichhornia crassipes (water hyacinth) without neglecting the roots, stems, leaves, and flowers and assessed for its ammonium removal efficiency in the study. Twelve biochars of two categories, viz., treated and normal, were produced under two different pyrolysis temperatures of 300 °C and 500 °C and three residence times of 30, 45, and 60 min. The adsorption experiments were conducted as batch studies in triplicate to examine the impacts of multiple adsorption-inducing factors in biochar. The maximum ammonium removal efficiency of about 83% was shown by the alkali-activated biochar produced at a higher temperature of 500 °C with a longer residence time of 60 min. The biochar showing higher ammonium adsorption was characterized by Scanning Electron Microscopy and Fourier Transform Infra-Red spectroscopy, which revealed the increased number of pores and the presence of C–O, OH, and CO groups that altogether aided the adsorption process. The kinetic study conducted with contact times of 30, 60, and 90 min showed that the linear regression values were >0.999 for the pseudo-second-order kinetic model, which revealed that the ammonia sorption of Eichhornia biochars followed a second-order mechanism of chemisorption. Synthesized biochar has shown significant efficacy in ammonia adsorption, making it worthwhile in applications where ammonia removal is necessary, particularly in wastewater treatment besides agriculture and air purification.

Molecular diversity and antimicrobial susceptibility profile of Vibrio species and distribution of other bacteria isolated from water Hyacinth (Eichornia crassipes) and Lagos lagoon

Molecular diversity and antimicrobial susceptibility profile of Vibrio species and distribution of other bacteria isolated from water Hyacinth (Eichornia crassipes) and Lagos lagoon

Introduction Pathways of Invasive Alien Plants in the Lake Cluster of Pokhara Valley, Nepal

The Lake Cluster of the Pokhara Valley (LCPV), a Ramsar site, has been invaded by several invasive alien plant species (IAPS), yet the introduction pathways of these species remain unknown. In this paper, the possible introduction pathways and invasion history of five wetland IAPS of the LCPV have been identified and reported for analysis. Direct field observations were combined with data obtained from the questionnaire survey with the local residents to identify introduction pathways and invasion history. Among five invasive alien plants, Pontederia crassipes and Pistia stratiotes were introduced as ornamental plants that escaped to wetlands and established their populations during 1980s and 1990s respectively. Similarly, Ipomoea carnea subsp fistulosa was introduced during the 1990s for fencing and soil bioengineering purposes. It is highly likely that Leersia hexandra and Alternanthera philoxeroides were introduced accidentally as none of the local residents interviewed could explain the purpose of their introduction. The local residents have noticed the occurrence of L. hexandra for &gt;50 years while A. philoxeroides might have reached to the LCPV sometime between 2015 and 2020. The results suggest the wetland IAPS have been introduced to the LCPV both intentionally as well as accidentally, and that the prioritizing pathway management can prevent their future introductions.

Naturally derived organic biochar as an alternative to commercially activated carbon in the oxygen removal of seafood processing wastewater

AbstractBACKGROUNDThe seafood processing industries are tremendously increasing in numbers which eventually discharge a large quantity of wastewater with a high range of biochemical oxygen demand (BOD) and chemical oxygen demand (COD), directly into the aquatic environment. A high level of BOD and COD in wastewater pertains to a higher level of pollution which must be reduced to prevent hazardous impacts on ecosystems. The main objective of the research aimed to develop cost‐effective biochar and to remove BOD and COD from processing wastewater using two natural biomasses: water hyacinth and sugarcane bagasse.RESULTSNaOH‐treated and non‐treated biochar for both water hyacinth as well as sugarcane bagasse were prepared through the process of pyrolysis carried out at 600 °C with three different residence times of 30, 45 and 60 min. The wastewater was initially analyzed for BOD and COD levels. The results showed that among all the groups of biochars, the water hyacinth NaOH‐treated biochar pyrolyzed at 600 °C for 60 min exhibited significantly (P &lt; 0.05) higher levels of reduction in BOD (86.6 ± 0.03%) and COD (94.3 ± 0.05%) at a residence time of 60 min in D2 (0.5 g (250 mL)−1). The maximum removal efficiency was observed for water hyacinth NaOH‐treated biochar pyrolyzed at 600 °C for 60 min.CONCLUSIONThe removal efficiencies of organic load revealed that the treated biochars exhibited a better reduction of nutrients. The biochar efficiencies when compared with those of activated carbon exhibited a higher removal level. The present research can be used to reduce BOD and COD levels in wastewater treatments. © 2024 Society of Chemical Industry (SCI).

Effect of n‐pentanol with novel water hyacinth biodiesel‐diesel ternary blends on diesel engine performance and emission characteristics

AbstractPresent research deals with crude oil production from water hyacinth biomass and its biodiesel preparation. Alcohol additive n‐pentanol is mixed with biodiesel and diesel blends to identify their effects on diesel engine performance and emission parameters experimentally. Water hyacinth oil (WHO) is produced through Soxhlet extraction technique, and its biodiesel is prepared by transesterification. n‐pentanol is mixed through magnetic stirring in biodiesel‐diesel blends to improve their combustion quality and efficiency. Prepared fuel blends properties are examined as per ASTM standards. Experimental results reveal that, BSFC and BTE are evaluated as 0.26 kg/kW‐h and 29.5%, respectively, with HC emissions as 29 ppm, CO emissions as 0.28 vol%, NOx emissions as 330 ppm and CO2 emissions as 2.21 vol% for WHB20D75P5 fuel at maximum load. The comparison of D100 and WHB20D80 with respect to WHB20D75P5 reveals 3.27% reduction and 7.27% improvement in BTE, respectively. Both HC and CO are reduced by 14.70% and 22.22% for WHB20D75P5 fuel compared to diesel. NOx and CO2 emissions are increased by 6.79% and 12.75% for WHB20D75P5 fuel compared to diesel. Overall, WHB20D75P5 fuel is the best performer.

Anaerobic sludge from a full-scale biodigester: physico-chemical and organic characterization, and principal component analysis (PCA)

The biological transformation of the organic fraction of municipal solid waste into bioenergy yields a solid digested material known as anaerobic sludge, comprising a mixture of organic and inorganic substances. This sludge holds significant potential as a renewable resource for agricultural reuse. However, there is also the potential risk of contamination from this material in receiving environments. Therefore, it is crucial to assess the characteristics of this material to ensure compliance with local regulations regarding its soil application, aiming to avoid adverse environmental impacts and ensure proper and viable disposal. In this study, conducted to explore the characteristics of bottom sludge collected from a pilot-scale anaerobic biodigester, various parameters were analyzed. The biodigester in question had a capacity of 1300 liters and a useful volume of 1000 liters, digesting food waste and water hyacinth (Eichhornia crassipes) in a ratio of 20% in terms of volatile solids from the macrophyte to the volatile solids of the food waste. A multivariate analysis was conducted on the following parameters: metals (Al, Ba, Cd, Cr, Cu, Fe, Mn, Mo, Pb, Se, V, Zn, Na, and K); total, fixed, and volatile solids; alkalinity; volatile fatty acids; ammonia; Kjeldahl nitrogen (NTK); and organic, inorganic, and total carbon (COT), to observe possible correlations among these parameters. Additionally, the sludge underwent nuclear magnetic resonance (NMR) analysis for detection and characterization of organic compounds. This approach provided a deeper understanding of the properties of anaerobic sludge produced strictly under the aforementioned conditions, contributing to further research in the field.

Effectiveness of aquatic plants as phytoremediation in palm oil processing factory wastewater

The research aims to see the effect of using kale (Ipomoea Aquatica), water hyacinth (Eichhornia crassipes) and apu-apu (Pistia statiotes) in the phytoremediation process on water quality in palm oil mill waste. The design used in this research is an experimental design using a non-factorial Completely Randomized Design (CRD). The treatments in the study used 4 treatments and three replications, namely P1: 20 liters of palm oil waste + 600 grams of water spinach, P2: 20 liters of palm oil waste + 600 grams of water hyacinth, P3: 20 liters of palm oil waste + 600 grams of apu-apu, P4: 20 liters of palm oil waste. The observation parameters in this study include pH, DO, Temperature, Nitrate and Phosphate. The results showed that the best aquatic plants in phytoremediation of palm oil wastewater were in treatment B (water hyacinth) and the lowest in treatment D (control). From the results obtained, it can be concluded that water hyacinth is suitable for use as a plant in phytoremediation and is able to improve the quality of palm oil wastewater.

Optimizing the Role of User and Maintainer Groups (Kpp) in the Settlement Quality Improvement Program (Case Study of Klasabi Slum Settlement, Sorong City)

The purpose of this research is to optimize the role of the user and maintainer group (KPP) in the Klasabi slum quality improvement program of Sorong City. In this case, the environmental conditions in this settlement are reviewed, the role of KPP is evaluated, and optimization strategies are also formulated that can be used for the environmental management of Klasabi slums in Sorong City. This research is quantitative with the method used in this research, namely the descriptive method with a case study technique through data collection from the results of distributing questionnaires, interview results, direct observation, and using other official documents analyzed using validity test analysis and reliability tests. Based on the results of the data validity test and the data reliability test, it was found that the research data or questionnaire data used in the study was valid and reliable. research data or questionnaire data used in this study is valid or reliable. The results showed that environmental conditions, seen from several perspectives, including ecological, economic, social, and cultural, can be considered good. However, when viewed in ecological conditions, especially in road and drainage conditions, it is still considered adequate by the community because there is no equal distribution of facility development. Also, the role of the user and maintainer group (KPP) is assessed as not optimal in carrying out its duties and responsibilities; this is supported by the results of the conducted interviews and observations made by researchers. In addition, optimization strategies can be carried out, such as structuring the Klasabi area around Deo Airport in Sorong City, handling slum houses by the government to support the development of water tourism, optimizing the use of water hyacinth plants that can be developed by community members using SIKIM and BLK facilities, and providing capital loans to support the business of making traditional snacks, traditional Papuan handicrafts, and Papuan craftsmen certification training in Sorong City.

Weeds and Their Response to Changing Climate: A Review

Climate change is one of the most important parameters to cause alteration in weed composition, population growth, life processes, physiological development, and infestation pressure. A few of the weed species may become inactive, while the rest may become aggressive invaders. Weeds possess unique biological characteristics and ecological range that enable them to tolerate and successfully intrude in any ecosystem with varied environmental conditions. Rising carbon dioxide, will benefit C3 crops to expand their photosynthetic capacity, thus leading to increased biomass production and productivity, on the other hand increased temperatures will benefit the C4 crops. These differences in response of C3 and C4 crops to changing climate will influence crop-weed interaction, most likely at the expense of crop. Moisture is another important environmental factor which plays a major role in weed seed germination, thus the survival. Temperature and relative humidity influence the course of absorption, translocation, and metabolism of herbicides in plants, any change in their range leads to decreased herbicide efficacy and thus the weed control. Studies focussed on the performance of weeds under elevated environmental factors help to make strategic decisions on their management before having their impact on change in weed biological aspects, and foresee the future with elevated temperature and carbon dioxide conditions. Weeds such as Parthenium hysterophorus, Sphagneticola trilobata, Prosopis juliflora and Eichhornia crassipes, have been identified as potential future threats. Consequently, exploring the bioprospecting potential of these weeds is seen as an inevitable necessity.

Sustainable seedling pots: Development and characterisation of banana waste and natural fibre-reinforced composites for horticultural applications

Plastic pots used in horticultural nurseries generate substantial waste, causing environmental pollution. This study aimed to develop biodegradable composites from banana pseudo-stem reinforced with agricultural residues like pineapple leaves, taro and water hyacinth as eco-friendly substitutes. The aim of this study is to develop optimised banana biocomposite formulations with suitable reinforcements that balance mechanical durability, biodegradation, and seedling growth promotion properties to serve as viable eco-friendly alternatives to plastic seedling pots. This study was carried out by fabricating banana fibre mats through pulping, drying and hot pressing. Composite sheets were reinforced with 50 % pineapple, taro or water hyacinth fibres. The mechanical properties (tensile, yield strength, elongation, bursting strength), hydrophilicity (contact angle, water absorption), biodegradability (soil burial test), and seedling growth promotion were evaluated through appropriate testing methods. The results show that banana-taro composites exhibited suitable tensile strength (25 MPa), elongation (27 %), water uptake (41 %) and 82 % biodegradation in 60 days. It was observed that biodegradable seedling trays fabricated from banana-taro composite showed 95 % tomato seed germination and a 125 cm plant height increase in 30 days, superior to plastic trays. The finding shows that the study demonstrates the potential of banana-taro biocomposites as alternatives to plastic nursery pots, enabling healthy seedling growth while eliminating plastic waste pollution through biodegradation.

Cotton aphid (Aphis gossypii Glover: Aphididae) influence associated to water hyacinth nutrient (Pontederia crassipes Mart.: Pontederiaceae) in lath house conditions in Great Rift Valley of Ethiopia

The cotton aphid, Aphis gossypii Glover is a polyphagous herbivore known worldwide. The aphid infestation could be considered as a challenge to crops, but an opportunity for alien invasive weed management. Hence, this study was initiated to investigate the potential of cotton aphid on the management of water hyacinth. Aphid-infested water hyacinth plants were used as a stock for rearing the aphid in a lath house at Ethiopian Sugar Corporation, Research and Development Center, Wonji. After rearing, randomly collected 30 aphids were placed onto water hyacinth plants cultivated under three nutrient levels. Aphid population, water hyacinth biomass and percent nitrogen and phosphorus were analyzed. The water hyacinth treated with a high nutrient level had the highest (295.0) mean aphids on apical leaves followed by the middle (178.3) and basal (104.7) leaves. The water hyacinth subjected to medium and no aphid treatment had the highest dry (44.3 g) biomass. However, when treated with a low nutrient level and aphids resulted in the lowest dry (31.9 g) biomass. Nitrogen and phosphorus concentrations were found high in the water hyacinth that received a high nutrient and no aphid treatment. The presence of the aphids reduced the biomass and nutrient concentration of the invasive weed. The findings of the current study revealed that the cotton aphid affected the water hyacinth in the lath house conditions in Ethiopia.