Chilli University (CCSHAU), Hisar, following recommended agronomic practices. Three

 Chilli crop was raised and transplanted during
summer at Entomological Research Farm, Chaudhary Charan Singh Haryana
Agricultural University (CCSHAU), Hisar, following recommended agronomic
practices. Three replications for each treatment (i.e. control, single and
double the application dose) were arranged in a randomized block design (RBD)
and the size of the each plot was (3m x 3m). The soil under crop was light
textured with low organic matter content.

2.4.1.
Application of the fungicide

We Will Write a Custom Essay Specifically
For You For Only $13.90/page!


order now

Tebuconazole (Folicur 25.9 EC) was
applied to the chilli plants at the recommended dosage (75 g a.i. ha-1)
and double the recommended dosage (150 g a.i. ha-1) using Knapsack
sprayer fitted with hollow cone nozzle. Untreated, control plots were also kept
for comparison and were sprayed with water only.

2.4.2.
Sampling procedure

Ripened chilli fruit samples
of  about 500g were collected randomly
separated from the control and treated plots of each treatment at 0 (1h), 1, 3,
5, 7, 10 and 15 days after application of the fungicide. The samples from each
treatment and each plot were collected separately, packed in polyethylene bags
and brought to the laboratory for processing. Samples of chilli collected from
field were divided into three portions, one portion processed as such, second
after washing with tap water, and third one after washing with 5% NaCl
solution.

2.5.
Extraction and clean-up

The
samples of chilli were processed and analyzed at the Pesticide Residue
Laboratory, Department of Entomology, CCSHAU, Hisar. Samples were extracted
immediately after sampling. After dividing into three parts, each sample was
chopped into small pieces and representative sample (15g) was macerated in
stainless steel mixer to make fine paste and was placed overnight into 10 ml
acetone in an Erlenmeyer flask following the method of Kumari et al. (2001) The
extract was filtered into 1 L separatory funnel was diluted with 600 mL brine
(10% NaCl) solution and partitioned the contents two times into 100mL and 50 mL
dichloromethane (DCM) and two times into 100mL and 50 mL n-hexane. Both
dichloromethane and n-hexane fractions were combined, dried over anhydrous
sodium sulphate and treated with 0.3 mg activated charcoal powder for about 2–3
h at room temperature. The clear extract so obtained was filtered through
Whatman filter paper No.1, concentrated to near dryness and again added about
20 mL of acetone and concentrated using rotary evaporator  at 30?C. Repeated the process to completely
evaporate dichloromethane and ethyl acetate and the final volume was
reconstituted