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The toxic impacts of zinc oxide nanoparticles (ZnO NPs) on reproductive potential of the earthworm, Eisenia fetida were studied in relation to varying temperature and pH in natural (NS) and artificial substrate (AS). The ZnO NPs decreased cocoon production, hatching and rate of reproduction as a function of increasing concentration, temperature and exposure period. The gradation of temperature and pH to get a better reproductive potential was found to be 25°C > 20°C > 30°C and 6:5 > 7:5 > 5:5, respectively. Cocoon production was higher in NS than the AS. It may be due to sufficient food availability in NS. Survival of adult worms was decreased with increase in ZnO NPs and exposure period. The rate of reproduction was signi ficantly higher in NS as compared to AS at 25°C. The present findings suggested that ZnO NPs retard the reproductive potential of E. fetida and may also be hazardous to pedoecosystem and fauna living there in. Temperature of 25°C, pH 6.5 and NS as vermibed were the most suitable conditions to maintain worthy rate of reproduction and reduce ZnO NPs toxicity. [ABSTRACT FROM AUTHOR]

This studydeals with the effects of disposal of industrial effluents on soilfaunal biodiversityaround Jodhpur city of Rajasthan in India. A lot of industrial units are working in Jodhpur.These industries release their effluents in water bodies and on land directly or indirectly. Effluents cause detrimental effects on soil system and fauna inhabiting there in are seriously affected. Twelve different polluted sites were chosen along the bank of river Jojari for faunal collection. A total 22 genera of different groups of soil fauna viz., earthworms, beetles, spiders, termites, millipedes, centipedes, mites, ants and insect larvae were recorded. Many annelids and arthropodswere affected with hazardous industrial effluents in polluted sites as compared to the non-polluted one. Soil fauna were more affected near to the disposal sites as compared to the distant places. Thus industrial pollution is greatly affecting the below-ground faunal biodiversity which may hamper function of ecosystem to provide goods and services. In most of the cases, the population of soil fauna either declined or showed absence in the polluted sites. In contrast, population of certain fauna in soil increased in response to effluent pollution. Whereas few soil faunal population remained unaffected. These selective impacts of industrial effluents may be assigned to the differences in food availability, faunal and soil characteristics and their interactions in polluted pedoecosystem. [ABSTRACT FROM AUTHOR]

Nanoparticles influence fauna, inhabiting soil ecosystem. The properties of bedding materials decide survival and growth of juveniles of earthworm. In the present study, we examined the effects of zinc oxide nanoparticles (ZnO NPs) on survival and growth of juvenile of the earthworm, Eisenia fetida in two different substrates for 28 days. Exposure of juveniles of earthworm to ZnO NPs in artificial substrate declined more body weight and length gain as compared to the natural substrate. Similarly, nanoparticles reduced increase in specific growth rate (SGR). Survival of juveniles in artificial substrate decreasedmore as compared to natural substrate,with increase in nanoparticle concentration. Thus ZnO NPs effectively reduced growth and survival in artificial substrate, while natural substrate (cowdung + horse manure) provided better and suitable environment for growth and survival of juveniles of earthworms. [ABSTRACT FROM AUTHOR]

Zinc oxide nanoparticles (ZnO NPs) have commercial uses but they may produce toxic effects in organisms inhabiting soil ecosystem. Hence, assessment of toxicity in soil organism is important. To assess toxicities, individuals of the earthworm Eisenia fetida were treated with varying concentrations of ZnO NPs for 1 to 14 days. Earthworm mortality was related to the concentration of ZnO NPs. The median lethal concentration (LC50) of ZnO NPs for different time durations was estimated. The LC50 values gradually decreased with exposure period. Thus there was an increase in toxicity of ZnO NPs as a function of increasing duration. The effects of pH and temperature on median lethal concentration of ZnO NPs were also determined. The LC50 value decreased if pH was higher and lower than 6.5 - 7. Similarly, the LC50 value declined below and above 25°C temperature. There were also some behavioral changes including dermal mucus secretion and alteration in coloration of earthworm in response to exposure of ZnO NPs. The study suggests that the use of zinc oxide nanoparticles should be reduced to protect the health of earthworms. [ABSTRACT FROM AUTHOR]

Abstract: Effects of alphamethrin (0.04ppm, 0.08ppm, 0.16ppm, 0.32ppm) on some metabolic dehydrogenases and proteins for 1, 2, 3, 4, 8 and 16days using three ecologically different earthworm species (Perionyx sansibaricus, Lampito mauritii and Metaphire posthuma) were studied. The first significant effect was on 2nd/3rd day and maximum response was achieved on 16th day of exposure of alphamethrin at all concentrations. Similarly, maximum effect was obtained at 0.32ppm alphamethrin at different exposure periods. It showed a dose- and duration-dependent inhibitory effects of a pyrethroid on enzymes and proteins of earthworms. There were approximately 47%, 43% and 41% declines in specific activities of cytoplasmic malate dehydrogenase (cMDH) of P. sansibaricus, L. mauritii and M. posthuma, respectively, in response to 0.32ppm exposure of alphamethrin for 16days. In case of similar treatment, specific activities of mitochondrial malate dehydrogenase (mMDH) showed 57%, 51% and 45% reductions in epigeic (P. sansibaricus), anecic (L. mauritii) and endogeic (M. posthuma) earthworms, respectively. Exposure of alphamethrin (0.32ppm) also decreased the specific activities of lactate dehydrogenase (LDH) by 47% (P. sansibaricus), 35% (L. mauritii) and 39% (M. posthuma) in different types of earthworms. The reductions in specific activities of a Krebs cycle enzyme (mMDH) were greater than that of a glycolytic enzyme (LDH). The protein contents declined significantly in the earthworms exposed to alphamethrin. The decreases of 41%, 36% and 30% were obtained in cytoplasmic proteins of P. sansibaricus, L. mauritii and M. posthuma, respectively. However, the mitochondrial proteins showed reductions of 45% in P. sansibaricus, 46% in L. mauritii and 38% in M. posthuma in response to alphamethrin (0.32ppm) intoxication for 16days. The decrease in the protein content reflected an inhibitory effect of alphamethrin on protein turnover. The most pronounced effect of alphamethrin was on metabolic enzymes and proteins of P. sansibaricus and least effect was found on M. posthuma. This clearly showed that surface dwelling species of earthworms (epigeic) are more vulnerable to toxic chemical than deep burrowing species (endogeic). Thus a possible ecophysiological link exists between the toxicological responses and ecological categories at metabolic level in tropical earthworms. [Copyright &y& Elsevier]

Impacts of different habitats on specific activities of LDH, cMDH, mMDH, cytoplasmic and mitochondrial proteins of M. posthuma, P. sansibaricus, L. mauritii were studied. Maximum specific activity of LDH of the earthworm M. posthuma and L. mauritii was observed in garden. In case of P. sansibaricus, maximum LDH specific activity was found in sewage. Minimum specific activity of LDH of the earthworm M. posthuma was found in non-cultivated field. However, P. sansibaricus and L. mauritii exhibited minimum activity in orchard and cultivated pedoecosystem, respectively. The maximum specific activity of cMDH and mMDH in earthworms from sewage and minimum from non-cultivated field (in case of M. posthuma), garden (in P. sansibaricus) and cultivated land (in L. mauritii) may be due to availability of more organic matter and nitrogen content in the former than in the later cases. Variations in specific activities of these metabolic enzymes due to changes in their pedoecological habitats clearly demonstrate the impact of pedoecosystem on respiratory capacity of the earthworms. Earthworms from pedoecosystem richer in organic matter and nitrogen showed elevated levels of cytoplasmic and mitochondrial protein. The changes in enzyme-specific activity and protein profiles were habitat specific. [ABSTRACT FROM AUTHOR]

Abstract: Exposure of epigeic (Perionyx sansibaricus), anecic (Lampito mauritii) and endogeic (Metaphire posthuma) earthworms to four different concentrations (10ppm, 20ppm, 40ppm and 80ppm) of carbofuran for 16days induced specific activities of cytoplasmic malate dehydrogenase (cMDH), mitochondrial malate dehydrogenase (mMDH) and lactate dehydrogenase (LDH). P. sansibaricus showed 33–52% increase in specific activities of aerobic (cMDH, mMDH) and anaerobic (LDH) enzymes and proteins (cytoplasmic and mitochondrial). In L. mauritii, the enhancement in enzyme and protein level was 30–46%. Similarly, M. posthuma indicated 29–43% increase in profile of enzymes and proteins. The significant increase was observed on 2nd or 3rd day and it was maximum on 16th day of carbofuran exposure. Maximum effect of carbofuran was on epigeic earthworm. The sensitivity of mitochondrial dehydrogenase and protein of different earthworm species to carbofuran appears to be associated with oxygen availability in different strata of soil habitats. Inductions in enzyme specific activity and protein content were concentration and time-dependent. The effect was more pronounced on aerobic enzymes (cMDH, mMDH) as compared to anaerobic (LDH) one. The increases in mitochondrial enzyme (47%) and protein (43%) were more than the cytoplasmic enzymes (35%) and protein (31%), which suggest a greater effect of carbofuran on respiratory metabolism of earthworms. The carbofuran-dependent increase in cytoplasmic and mitochondrial enzymes and proteins might be due to increased synthesis of metabolic enzymes and stress proteins. [Copyright &y& Elsevier]

Abstract: The effects of an organophosphate pesticide phorate on cytoplasmic malate dehydrogenase (cMDH), mitochondrial malate dehydrogenase (mMDH), lactate dehydrogenase (LDH), supernatant and mitochondrial proteins of an epigeic (Perionyx sansibaricus), anecic (Lampito mauritii) and endogeic (Metaphire posthuma) earthworms were studied. The treatment of different concentrations (20, 40, 80 and 160ppm) of phorate for 16days gradually decreased the specific activities of cMDH, mMDH and LDH as well as cytoplasmic and mitochondrial protein contents. This showed the inhibitory effect of phorate on metabolic enzymes and proteins in tropical earthworms. The inhibition was dose- and time-dependent. The inhibitory response in mitochondrial enzyme (mMDH) and protein was somewhat earlier and more as compared to the inhibitory effect of phorate on cytoplasmic enzymes (cMDH, LDH) and protein. This indicates a greater interference of phorate in cellular respiration of earthworms. The phorate related decreases in enzyme and protein profiles were about 60% and 58% in P. sansibaricus, 54% and 49% in L. mauritii and 47% and 42% in M. posthuma, respectively. It reflects phorate-induced substantial decline in protein synthesis and aerobic and anaerobic capacity of earthworms. The maximum effect of phorate was on epigeic earthworm followed by anecic and endogeic species. The present findings suggest the differential sensitivity of different earthworm species in enzymatic and protein responses to phorate and the sensitivity was associated with the ecophysiological categories of earthworms. [Copyright &y& Elsevier]

Comparative studies were performed to evaluate composting potential, biomass growth and biology of a non-native (Eisenia fetida) and an endemic (Lampito mauritii) species of earthworm in the semiarid environment of Jodhpur district of Rajasthan in India. Earthworms were reared in a mixed bedding material comprised of biogas slurry, cowdung, wheat straw, leaflitter, sawdust and kitchen waste. The percentage of organic carbon of the culture bedding material declined upto 105 days with E. fetida and 120 with L. mauritii. The percentage of nitrogen, phosphorous and potassium increased as a function of the vermicomposting period. In contrast, C/N and C/P ratios decreased day by day. Both species were effective for decomposition and mineralization of mixed bedding in the semiarid environment. A comparative assessment of biomass growth of E. fetida and L. mauritii was done under controlled laboratory conditions. The optimum temperature, moisture content and pH for E. fetida were 25 °C, 70% and 6.5, respectively. However, the optimum temperature, moisture content and pH for growth and development of L. mauritii were 30 °C, 60% and 7.5, respectively. The biology and reproductive rates of both species were also studied in the laboratory using mixed bedding. Cocoon production was higher for E. fetida than L. mauritii. The net reproductive rate was 9 per month in the case of E. fetida and 1 per month for L. mauritii. Fertilized eggs of E. fetida and L. mauritii developed into adults within 4 and 51/4 months, respectively. These observations indicate E. fetida may be a more efficient breeder than L. mauritii in the desert region of Rajasthan. [Copyright &y& Elsevier]

An epigeic (surface dweller) earthworm species Eisenia fetida and an anecic (deep burrower) earthworm species Lampito mauritii have been tested for decomposition of kitchen waste plus cow dung. Chemical analyses of worm-worked substrates by both species showed g/kg increases in nitrogen, phosphorus and potassium and decreases in C/N and C/P ratios after 150 days of vermicomposting. However, organic carbon matter showed reduction in their amounts for 3–4 months and afterwards slightly increased up to 150 days. E. fetida produced 0.27%, 156%, 41% and 38% increases in organic carbon, nitrogen, phosphorus, and potassium as well as 61% and 29% decreases in C/N and C/P ratios as compared to control after 150 days of earthworm inoculation. In contrast, L. mauritii produced 14%, 102%, 33% and 42% increases in organic carbon, nitrogen, phosphorus and potassium as well as 43% and 14% decreases in C/N and C/P ratios as compared to control after 150 days of earthworm activity. There was moderate mineralization and faster decomposition by E. fetida in comparison to moderate mineralization and moderate decomposition by L. mauritii. The average numbers of cocoons and adults produced were greater by E. fetida than by L. mauritii after 150 days. These results indicate E. fetida may be a better adapted species for decomposition of kitchen waste plus cow dung under tropical conditions. [Copyright &y& Elsevier]