Coir Pith Research Articles

EFFECT OF COIR PITH COMPOST, BONE MEAL POWDER AND PANCHAGAVYA ON GROWTH, CHLOROPHYLL CONTENT AND DMP OF BARNYARD MILLET

To investigate the effect of different organic nutrient sources on growth, chlorophyll content and dry matter production of barnyard millet (Echinochloa frumentacea (Roxb.) Link) in sandy loam soil, a pot experiment was conducted at the Department of Soil Science and Agricultural Chemistry, Annamalai University during February-May, 2019. The weather at Annamalainagar was moderately warm with hot summer. The experiment was laid out in completely randomized block design (CRD) with nine treatments and three replications. The treatments of the study were T1– Control, T2 –100% RDF, T3 – Coir pith compost @ 10 t ha-1, T4 – Bone meal powder @ 1 t ha-1, T5 – Panchagavya @ 3 % (Foliar spray), T6 –T3 + T4, T7 – T4 + T5, T8 – T3 + T5 and T9 – T3 + T4 + T5. The results revealed that application of 100% RDF (N: P2O5: K2O @ 40:30:50 kg ha-1) (T2) recorded the highest plant height of 159.74 cm, number of leaves plant-1 (8.51), leaf area index (3.12), chlorophyll content (49.14) and dry matter production (472.30 g pot-1) at harvest stage. These were on par with T9 – CPC + BMP + PG.

Effect of crop geometry and in situ soil moisture conservation practices on yield attributes and yield of upland rice (Oryza sativa L.)

Rice is the most widely grown crop in India. With the decreasing availability of water for irrigation, farmers are now switching towards water efficient production systems such as upland rice. Moisture stress at critical stages is one of the major reasons for low productivity of upland rice. So, the present study was conducted at college of Agriculture, Vellayani, Thiruvananthapuram, Kerala Agricultural University, Kerala, India. The experiment was conducted in RBD with nine treatments including two crop geometries viz., normal planting (20 cm x 10 cm) and paired row planting (10 cm x 10 cm) with 40 cm between paired rows, three rows of cowpea are grown in between two paired rows and in situ soil moisture conservation practices viz., live mulching of cowpea, hydrogel application and coirpith compost application were compared and analysed statistically on yield parameters and yield. Results revealed that, the treatment T9 (Paired row planting with live mulching of cowpea, hydrogel and coir pith compost application) favorably influenced the yield characters and yield of upland rice through proper conservation of moisture and improved availability of nutrients. The treatment T9 recorded the highest grain and straw yields of 3825 and 7700 kg ha-1 respectively with a harvest index (0.48) and was significantly superior to other treatments. It also recorded the highest moisture content in the soil as well as the maximum uptake and availability of nutrients.

Chromium adsorption on coir pith charcoal from tannery wastewater

Emission of high chrome tanning wastewater is catastrophic for the environment. In this work, the effectiveness of coir pith charcoal is stated for the removal of chromium from tannery wastewater. The charcoal yield from the coir pith was 2.4%. The prepared charcoal was characterized by Fourier transform infrared spectroscopy (FT-IR). The efficiency of coir pith charcoal for chromium removal was assessed experimenting with various parameters e.g., charcoal dose, contact time, and relative pH. The content of chromium in the raw wastewater and after treatment at filtrate was 3439.2 mg/L and 14.9 mg/L, individually. In the batch experiment at optimized condition, for 75 mL chrome wastewater at 4 g charcoal dose with 15 min contact time, the chromium removal efficiency was attained 99.6%. The level of chloride (Cl-), chemical oxygen demand (COD), and biochemical oxygen demand (BOD) were significantly reduced by 65.7%, 93.7%, and 95.6%, respectively. The use of coir pith charcoal could be an alternative source for the removal of chromium from chrome containing wastewater.
 Bangladesh J. Sci. Ind. Res.56(1), 53-60, 2021

Residual effect of organics and direct effect of mineral nitrogen on rice (Oryza sativa L.) in two different textural soils

Nitrogen through organics and inorganics application is an alternate to maintain soil health and crop productivity in the rice cropping system. With this background, field experiments were conducted in farmer’s field at Kuttalam during 2012-2013, 2013-14 to evaluate residual organics and mineral nitrogen (100%N) on growth parameters and yield of rice (Oryza sativa) in sandy clay loam and clay loam soil. The treatments consisted of residual organics viz., composted coir pith (CCP), green manures (GM), sugarcane trash compost (STC), vermicompost (VC), poultry manure (PM) and FYM applied(100%N) and a combination of above residual organics with urea@50%N besides 100% recommended dose of nitrogen (RDN) and control. The results revealed that residual organics and urea recorded higher growth parameters like plant height, chlorophyll content, leaf area index(LAI), crop growth rate (CGR), relative growth rate(RGR), net assimilation rate(NAR), No. of tillers/hill compared to their individual addition. The growth parameters were more under residual PM in combination with mineral nitrogen in both the soils. Residual PM + fertilizer nitrogen (100% N) recorded highest grain (4485, 4693 kg ha-1) and straw yield (6984, 5897 kg ha-1) in clay loam and sandy clay loam soils, respectively. The lowest grain(3292, 2993 kg ha-1) and straw yield(4998, 4003 kg ha-1) were recorded in residual GM + fertilizer (100% N) in both soils. Among organics alone, residual PM(100% N) registered highest grain yield (4025, 4048 kg ha-1) in both soils. It can be concluded that the application of poultry manure alone or in combination with N fertilizers enhanced the growth and improved soil health.

Characterization of Coir Pith Ash Blended Cement Pastes

Characterization of Coir Pith Ash Blended Cement Pastes

Evaluating a preparation of malathion‐tolerant Aspergillus niger MRU01 for accelerated removal of four organophosphorus insecticides

AbstractBACKGROUNDMicrobial degradation of organophosphorus (OP) insecticides has emerged as an efficient and cost‐effective technology for removal of pesticide residues from soil. Malathion‐tolerant Aspergillus (Aspergillus niger MRU01) was developed, mass cultured, harvested, mixed with coir pith at 3% on dry weight basis, shade‐dried aseptically to a 5% moisture level and stored for 60 days. The growth, metabolic activity and insecticide removal efficiencies of the preparation were evaluated at 15‐day intervals.RESULTSNo significant change in the growth performance was observed up to 45 days of storage, after which viability decreased. The activities of carbohydrate enzymes (cellulase, invertase and amylase) and protein and carbohydrate contents of the preparation, however, did not significantly change during the experimental period. The preparation showed accelerated activities of esterases and phosphatases after treatment with malathion (500 μmol L−1), parathion (470 μmol L−1), chlorpyrifos (260 μmol L−1) and dimethoate (680 μmol L−1). The highest activity of the esterase and phosphatase enzymes was observed with malathion and the minimum with parathion treatment. Nearly 70% of the applied malathion was removed from the medium by the preparation during 5 days of incubation followed by dimethoate (68%), chlorpyrifos (58%) and parathion (54%).CONCLUSIONSThe fungal preparation was highly effective in removing malathion as well as the other three OP insecticides. A storage period of 45 days may be considered ideal for maintaining the preparation in the active state, and is recommended for field application after evaluating its efficacy under field conditions. © 2021 Society of Chemical Industry

Bacillus aryabhattai TFG5-mediated synthesis of humic substances from coir pith wastes

BackgroundHumic substances (HS) form the largest proportion among all the constituents of soil organic matter and are a key component of the terrestrial ecosystem. HS plays a multifunctional role in the environment by controlling the biogeochemical carbon cycle, providing nutrients and bio-stimulants for plant growth, and interacting with inorganic and organic pollutants. The rate of formation of HS in soils determines its productivity and carbon sequestration capacity. Enhancement of HS synthesis in the soil through the microbial route not only increases CO2 sequestration but also mitigates the greenhouse gas emissions in the environment.ResultIn this study, we attempted to understand the mechanism of formation and enhancement of HS from coir pith wastes using the tyrosinase produced by Bacillus aryabhattai TFG5. The bacterium TFG5 isolated from the termite garden produced the tyrosinase (1.34 U mL−1) and laccase (2.1 U mL−1) at 48 h and 60 h of fermentation, respectively. The extracellular tyrosinase from B. aryabhattai TFG5 was designated as TyrB. Homology modeling of TyrB revealed a structure with a predicted molecular mass of 35.23 kDa and two copper ions in the active center with its conserved residues required for the tyrosinase activity. TyrB efficiently transformed and polymerized standard phenols, such as p-cresol, p-hydroxyl benzoic acid, Levo DOPA, and 2,6 DMP, besides transforming free phenols in coir pith wash water (CWW). Additionally, UV–Vis and FT-IR spectra of the degradation products of the coir pith treated with TyrB revealed the formation of HS within 3 days of incubation. Furthermore, the E472/664 ratio of the degradation products revealed a higher degree of condensation of the aromatic carbons and the presence of more aliphatic structures in the HS.ConclusionThe results confirmed the influence of TyrB for the effective synthesis of HS from coir pith wastes. The results of the present study also confirm the recently accepted theory of humification proposed by the International Humic Substances Society.

WITHDRAWN: Removal of phosphorus from contaminated water sources using composite matrix fabricated from agro-based waste materials

In the present scenario, increasing population has put a tremendous pressure on various environmental sources. Water bodies are getting polluted due to industrial discharges leading to life threatening diseases and contaminations. In the present study, an attempt has been made to monitor the impact of various industrial waste discharges in River Rushikulya and its impact on phosphorus contamination in the available water sources. In this process, agro based waste materials are being taken as the base material to treat the contaminated water. An efficient and stable absorbent has been prepared using rice husk and Coir Pith based activated material for phosphorus removal. In this Context, various combinations of absorbents are prepared and subjected to testing for their physical, chemical and mechanical parameters including stability and recycling. The data revealed that by using an absorbent prepared with 60% rice husk and 40% Coir Pith, it is possible to remove 95% of the phosphate from the contaminated water sources.

Characterization and Evaluation of Energy Properties of Pellets produced from Coir pith, Saw dust and Ipomoea carnea and their blends

ABSTRACT In the present study, pelletization of coir pith, deodar wood saw dust, Ipomoea Carnea, and their blends was performed. The effects of binary and tertiary blends on fuel properties and quality of pellets were investigated. The physicochemical properties, higher heating value, pellet density, water resistance capacity, durability, thermal performance, and emission factor of all pellets were determined. All the properties were compared with the European EN ISO 17,225–2 standard. Calorific values of all pellets were found more than 17 MJ/kg. Pellet density of pellets was above 600 kg/m3. The durability of pellets was in the range of 92.056– 97.761%. The present study showed that the pellets produced from binary blends were superior in terms of ash content, volatile matter, durability, and thermal efficiency. This study showed that these pellets with high energy density and low CO and CO2 emission can be novel contribution to bioenergy options.

Experimental investigation on properties of coir pith and its influence as partial replacement of fine aggregate in concrete

As the civilization is evolving and rapid growing modernization many technical advancements has been made, which resulted in depletion of natural resources. One of the main natural construction materials is river sand, the demand for the stand increasing day-by-day. To meet the desired needs at economical ways partial usage of coir pith may be used. The outer fibre, which is taken out from the dried coconut husk is named as coir pith. These fibres are commonly discarded as an agricultural waste product. Dumping of huge quantity of coir pith in fertile or any good quality land creates numerous health problems and these lands get disturbed both physically and chemically due to its less deterioration in soil. The major properties of coir pith are an excellent moisture retention material even after drying. Enhancing internal curing maintains uniform temperature and retained all over the process of concrete to reduce or completely rid of certain crack problems like thermal shrinkage. The process of maintaining the moisture content inside the concrete for a particular period gives or enhance mechanical strength and thus it was names as curing period of concrete. This concrete possesses greater physical resiliency that withstands compression better, resulting in greater compressive strength, also 100% degradable, organic and a renewable resource and also making it economical. This paper describes various methods adopted to partially replace coir pith to fine aggregate and suggest some of the methods for utilizing coir pith in construction industry. Experimental analysis to find the physical and strength properties of coir pith are done. Comparatively treated coir pith gives better result than untreated coir pith on the basis of strength and bonding property with concrete.

Life Cycle Assessment of Various Filtering Media for Greywater Treatment Using Greenwall Filtration System

The risk of global water crisis is becoming more evident due to the increase in overall global urban population and reduction of freshwater availability. Treated greywater using greenwall technology was identified as a potential method to produce water for non-potable applications. The filtering media in greenwall technology acts as a growing media for the plants and as a filtration medium. In this study, the pollutant removal efficiency and environmental impacts associated with two filtering medias (coir pith and perlite) were investigated. The coir pith was found to have higher removal efficiencies for both COD and TSS removal compared to perlite. Besides, the life cycle of each filtering media used for greywater treatment in greenwall technology were compared. Coir pith was found to have a higher environmental impact on global warming potential (1.19568 kg CO2 eq.) and freshwater consumption (0.00066295 m3), while perlite was found to have a higher environmental impact in terms of fossil depletion (0.045562 kg oil eq.) and terrestrial ecotoxicity (0.008508135kg 1,4-DB eq). In conclusion, this study provides a framework for in-depth data analysis of the entire life cycle of filter media and a decision-making tool for the selection of suitable filtering media for greenwall filtration system.

Systems approach in coconut for higher productivity and profitability in coastal ecosystem of Maharashtra

The field experiment conducted on systems approach in coconut for higher productivity and profitability in coastal ecosystem at ICAR-AICRP on Palms, Regional coconut Research Station, Bhatye, Ratnagiri, (DBSKKV, Dapoli), Maharastra during the year 2013-14 to 2017-18, showed that the application of organic manures in combination with inorganic fertilizer either in 75 per cent of recommended NPK +25 per cent of N through organic recycling with vermi-compost or 50 per cent of RDF+50 per cent of N through organic recycling with vermi-compost +vermiwash application +bio-fertilizer application +in situ green manuring resulted in higher yield of 141.28 nuts palm-1 year-1 and 126.33 nuts palm-1 year-1, respectively. Soil organic carbon was higher, where 75 per cent of recommended NPK +25 per cent of N through organic recycling with vermi-compost (T1) was added. Microbial population of fungi were higher where 100 per cent of N through organic recycling with vermi-compost +vermiwash application +bio-fertilizer application +in situ green manuring and green leaf manuring +composted coir pith, husk incorporation and mulching with coconut leaves (T3) was added, whereas the bacteria and actinomycetes present in top soil were higher in the former treatment where 50 per cent RDF + 50 per cent N through organic reyching with vermicompost + vermiwash + bio-fertilizer + in situ, respectively was given. Earthworm population was highest in the treatment T3 followed by the treatment T1 and T2. Highest (3.03) benefit:cost ratio was recorded in T1 followed by T2 (2.81) as against the control having monocrop of coconut with recommended NPK and organic manure.

Assessing Different Media Composition on Germination, Growth and Yield of Transplanted Sesame (Sesamum indicum L.)

Sesamum, a traditional oilseed crop, is susceptible to poor plant establishment due to various biotic and abiotic factors for which transplanting is a suitable option. Still, suitable media for promoting the growth and establishment of sesame seedlings have not yet been exploited. Therefore, a preliminary field experiment was conducted in 2019 at Agricultural College and Research Institute, Tamil Nadu Agricultural University, Madurai, India, to study the effect of various media compositions on the performance of transplanted sesame. Media compositions such as red earth, FYM, vermicompost and composted coir pith were used. The experiment was laid out in randomized block design with four replications. Results revealed that higher seed germination percentage ( 88), establishment percentage (94), vigor index (1674), seedling height (15 cm), capsules plant-1(83), seeds capsule-1 (58), and seed yield ( 839 kg ha-1) were recorded in media comprising red earth: sand: vermicompost: composted coir pith (2:1:1:1) followed by red earth: sand: vermicompost (2:1:1). Therefore, the media composition of red earth: sand: vermicompost: composted coir pith is highly suitable for promoting growth, seedling vigor, and yield enhancement in transplanted sesame.

Nonlinear regression analysis and response surface modeling of Cr (VI) removal from synthetic wastewater by an agro-waste Cocos Nucifera: Box-Behnken Design (BBD)

In this study mixture of coconut shell and coir was used for Cr (VI) removal from synthetic wastewater and statistical tool Response Surface Modeling (RSM) was applied to optimize process parameters. The solution pH (2–6), reaction time (20–100 minutes) and adsorbent quantity (0.03–0.2 g) was optimized to find the maximum response of Cr (VI) removal using statistical Box-Behnken design (BBD) software. The equilibrium data obtained by the batch experiment were analyzed by ANOVA and found fitted in a second-order polynomial equation through multiple regression analysis. The optimum value of pH, adsorbent quantity and reaction time for 99% of Cr(VI) was found as 2, 0.1 g and 100 minutes, respectively. By using non-linear regression method it was found that Freundlich isotherm and Pseudo-second-order kinetic with high correlation coefficient (R 2), low Chi-square (χ 2) and root mean squares errors (RMSE), best describe the adsorption of Cr (VI) on mixture of coconut shell and coir (MCSC) surface. Positive enthalpy (ΔH°) and negative Gibbs free energy (ΔGo) values confirm the endothermic and spontaneous nature of adsorption process. Pre and post adsorption phenomenon was confirmed by characterization of adsorbent using AFM, FTIR, SEM, and EDX analysis. The adsorbent MCSC has regenerative property and can be reused 3–4 times after treating with alkaline medium (0.2 N NaOH) and offered more than 60% removal of Cr (VI) at the fourth cycle. It can be inferred based on this study that MCSC is an effective adsorbent for Cr (VI) removal and can be used on an industrial scale for social and environmental benefit. Novelty statement An agriculture waste mixture of coconut shell and coir (MCSC) without the addition of any chemical reagent, was used for Cr(VI) removal. As per literature survey and best of our knowledge, the adsorbent MCSC has not been reported for Cr (VI) removal. In the previous study, authors reported either coconut coir pith or coconut shell or coconut charcoal as adsorbent for Cr (VI) removal. The adsorbent MCSC is efficient even at very low doses (0.1 g) as compared to the reported adsorbent.

Community-level management of bio-resources for augmenting income from coconut-based farming systems in Kerala state, India

On-farm management of farm residues for mass multiplication of beneficial microbes plays an important role in organic farming as well as integrated nutrient management by improving soil health. Community-level production of organic inputs from crop residues can be a potential source of income for farmers’ groups also. A large scale operational research on community-based bio-resource management, along with soil test based nutrient management, was undertaken by ICAR-CPCRI with financial support from NABARD in the major organic tract of Kerala in the coastal belt - Kanjikuzhy block during 2014-2016. The bio-resource management components under technology integration included farm-level production of organics from crop residues, enrichment using bio-agents, utilization of enriched organics for soil and plant health management and production of bio-primed planting materials. For enhancing the efficiency of Trichoderma-enriched organic manure, two ideal media viz., coir pith compost + neem cake (4:1) and coir pith compost + neem cake + poultry manure + cow dung (2:1:1:1) were standardized. Coconut seedlings produced through bio-priming with Trichoderma sp. showed early germination (90%), higher recovery percentage (79.5%), higher collar girth (17 cm), more number of fronds (9) and height (160 cm). Farm-based participatory action management integrating cost-effective bio-resource management interventions in coconut-based farming systems resulted in improvements in income from coconut by 26 per cent and intercrops by 142.9 per cent, contributing to an increase in the average farm income by 149.8 per cent. The average knowledge index of the respondents related to bio-resource management increased by 115.8 per cent and that of integrated nutrient management by 74.5 per cent.

Solarisation – An effective low cost substrate sterilization technique for the cultivation of milky mushroom (Calocybe indica)

The increasing crop production is generating huge amount of agricultural waste creating serious environmental pollution and hazards. The agro wastes composed of lignin are the recalcitrant fractions which pose serious threat to nature. Utilization and recycling of agro waste in mushroom cultivation is one the eco-friendly profitable venture. In this context a study was conducted to evaluate the biological efficiency of milky mushroom production by utilising agro wastes as substrates subjected to different sterilisation procedures. The substrates used were paddy straw, spent mushroom substrate (SMS), and coir pith subjected to sterilization procedures viz., boiling, solarisation and chemical method. Solarisation of substrates SMS and paddy straw gave better mycelial growth and took minimum period for spawn run, initial production and harvest. SMS gave more number of sporophores and yield when compared to paddy straw and coir pith. Solarisation was the best sterilisation procedure for obtaining higher yield of milky mushroom. The coir pith substrate subjected to solarisation and boiling showed heavy incidence of contaminants viz., Trichoderma and Coprinus. The solarised SMS was the best substrate and sterilisation combination in producing higher yield of milky mushroom.

Adsorption of chromium (VI) ion using adsorbent derived from lignin extracted coir pith

In this study, coconut coir pith (cellulose-lignin compound) was first treated with water and sodium hydroxide solution to remove lignin and impurities, then lignin-extracted coir pith was calcined at 200°C for 6 h. The obtained absorbent was applied to remove Cr(IV) ions by using adsorption method. Some analytical methods such as thermal gravimetric analysis (TGA), Fourier Transform Infrared Spectroscopy (FT-IR), Brunauer–Emmett–Teller analysis (BET), X-ray powder diffraction analysis (XRD), pHpzc analysis, Boehm titration and potentiometric titration were employed to characterize structure, specific surface area, functional groups and surface charge of the absorbent. Adsorption results showed that 95.23% of Cr(IV) was removed from solution of 100 mg.L-1 by using certain amount of absorbent at pH 2.0 within 20 min at room temperature. Kinetics of Cr(VI) adsorption from aqueous solution on absorbent fit to Pseudo-second-order kinetic equation and adsorption isotherm of Cr(IV) followed to Freundlich model.

Transforming waste disposals into building materials to investigate energy savings and carbon emission mitigation potential.

This work aims to enhance the energy cost-saving potential of conventional mud-brick by including natural waste materials as insulators. The solid waste materials considered for mud bricks are rice husk, sawdust, coir pith, and fly ash. This work investigates the structural and thermoeconomic performance of four types of insulated mud bricks and three roofs of ferrocement, clay, and ceramic materials. The thermal properties of walls and roofs were measured as per ASTM D 5334 standards. The utilization of solid waste in mud bricks enhanced the structural properties and air-conditioning cost-saving potential of the mud bricks. The results also showed the mitigation of greenhouse gas emissions with the usage of insulated bricks for buildings. The rice husk mud-brick wall showed better results of higher time lag, lower decrement factor, higher air-conditioning cost-savings, acceptable payback periods, and higher annual carbon mitigation values of 11.11 h, 0.24, 1.74 $/m2, 1.17 years, and 33.35 kg/kWh, respectively, among all the studied multilayer walls. Among the roofs, clay tile roof showed a lower decrement factor (0.989), higher time lag (0.73 h), higher air-conditioning cost-savings (2.58 $/m2), lower payback periods (0.61 years), and higher annual carbon mitigation (21.73 kg/kWh). The results are in designing eco-friendly and energy-efficient envelopes for buildings.

Microbial conversion of vanillin from ferulic acid extracted from raw coir pith

Coir pith, an agro-industrial residue, is resistant to natural degradation, and its accumulation causes environmental pollution. Ferulic acid, a precursor of vanillin, was extracted from the raw coir pith by chemical pre-treatment such as alkaline hydrolysis, acidification, and liquid–liquid extraction method. The obtained ferulic acid (1.2 g/50 g) was analysed using high-performance liquid chromatography (HPLC) and used as a substrate for biotransformation by Aspergillus niger to vanillic acid, which, in turn, was fermented by using Phanerochaete chrysosporium to vanillin. The quantity of vanillic acid detected by HPLC on the third day of incubation was 0.773 g/L, while the optimal yield of vanillin on the subsequent third day of incubation was 0.628 g/L. Thus, the chemical extraction of ferulic acid from coir pith ensued bioconversion into vanillin. These products are highly valuable and economical to be used in industries such as pharmaceuticals, health, cosmetics, and neutraceuticals.

Soil persistence and environmental risk assessment of chlorpyrifos under different organic manuring in the tropical sugarcane ecosystem

ABSTRACT Chlorpyrifos has label claim against sugarcane termites and is applied as a soil drench at planting. The organic manures viz., composted coir pith, farmyard manure, press mud and sugarcane trash are also applied at the time of planting mainly to conserve the soil moisture in the tropical environment. The organic manures may have some impact on the persistence of chlorpyrifos in the soil. Hence, the persistence of chlorpyrifos in the manurial soils was studied by employing the single-step sample preparation method and GC-ECD. The initial deposits of chlorpyrifos were 0.325–0.383 µg/g across the treatments involved in the study. The residues were quantified up to 75 days after treatment (DAT) and were below 0.01 µg/g on 90th DAT. The soil half-lives of chlorpyrifos were in the range of 19.8–21.0 days in the manured soils as against 18.7 days in the control soil. Thus, the organic manures applied at planting did not play any significant role in influencing the persistence of chlorpyrifos in the sandy clay loam soil of tropical sugarcane ecosystem. Further, the chlorpyrifos residues were not detected in the sugarcane leaf and stalk, indicating that there was no significant uptake by the plant from the soil. The calculated risk quotient values indicated that the chlorpyrifos residues may pose an unacceptable risk to earthworms during the first week of its application and thereafter, there could be a moderate level of risk in the tropical sugarcane environment.