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The World of Protozoa, Rotifera, Nematoda and Oligochaeta

Perionyx excavatus

The Asian epigeic species. (ref. ID; 6841)

[ref. ID; 6841]

Test system

Sublethal toxicity test

Strains

20 days old (0.0026+/-0.0020 g).

Toxicants

Pb(NO3)2. The concentration in the cattle manure was 0.2% (2000 ug/g), dry weight by wet weight.

Test design

Six plastic containers (1 control and 5 experimental) with a volume of 2 L each were used. Twenty worms were placed in the six plastic containers filled with 400 g of substrate (fresh, urine-free cattle manure that was sun-dried, particle size 500-1000 um). Control earthworms were fed 60 g fresh, urine-free cattle manure. Experimentals earthworms were fed 60 g fresh, urine-free cattle manure mixture with 0.12 g of lead nitrate. The container lids were perforated and covered with fine gauze to allow aeration and to keep the worms from escaping. pH ~~7 and moisture content 70-80%. Temperature 25 degrees C. Experimental period 76 days.

Measurements/observations

Biomass, maturation rate, and cocoon production, hatching success of the cocoons and tissue lead concentrations in worm.

Evaluations

Student t-tests (parametric) or Mann-Whitney tests (nonparametric) were used.

[ref. ID; 7085]

Test system

96-hr LC50

Strains

Specimens were collected from the grasslands, around Midnapore town (West Bengal, India), that has never been used for any agricultural purpose and pest control. Age synchronized specimens (250-300 mg).

Toxicants

Aldicarb, Carbaryl, Chlorpyrifos, Cypermethrin, Endosulfan, Monocrotophos.

Test design

Small inert polythene boxes (16x12x1 cm; total area, 192 cm2) were used. The experimental boxes filled with 200 g grassland soils, and were kept in a BOD incubator at a constant temperature of 28+/-0.5 degrees C and 50% moisture. 3 replicates for each level. Different levels of the insecticides based on their recommended agricultural doses (RAD) (viz RAD, 1/2X-RAD, 2X-RAD and 3X-RAD) and control. 5 worms per box.

Measurement/observations

Mortality.

Evaluations

[ref. ID; 7159]

Test system

Contact test (48 hr) and aritifical soil test (2 weeks)

Strains

Toxicants

Carbaryl, 1,2-Dichloropropane, Dimethyl phthalate, Fluorene, Nitrobenzene, N-nitrosodiphenylamine, 4-Nitrophenol, Phenol, 1,2,4-Trichlorobenzene, 2,4,6-Trichlorophenol.

Test design

Measurements/observations

Mortality.

Evaluations

[ref. ID; 7163]

Test system

Contact test (2 days) and soil test (14 days)

Strains

Toxicants

Carbaryl, 1,2-Dichloropropane, Dimethyl phthalate, Diphenylnitrosamine, Fluorene, Nitrobenzene, 4-Nitrophenol, Phenol, 1,2,4-Trichlorobenzene, 2,4,6-Trichlorophenol.

Test design

Standard protocols.

Measurements/observations

Mortality.

Evaluations

LC50 and Weibull function.