International Journal of Current Microbiology and Applied Sciences
ISSN: 2319-7706 Volume 2 Number 9 (2013) pp. 5-13
Persistence Study of Pyraclostrobin and Epoxiconazole fungicide formulation in Groundnut plant followed by HPLC-UV method
Tentu Nageswara Rao* 1 , E.G. Sreenivasula Reddy2 , G.Rajamohan Reddy3 , D.Sreenivasulu4 and Jakkula Ramesh
1Department of Chemistry, Krishna University, Machilipatnam, Andhrapradesh, India 2Department of Organic Chemistry, SK University, Anantapur, Andhrapradesh, India 3Department of Microbiology, Osmania University, Hyderabad, Andhrapradesh, India 4Department of Chemistry, SV University, Tirupathi, Andhrapradesh, India *Corresponding author e-mail: tentu6581@rediffmail.com
ABSTRACT
Dissipation of systemic fungicides of Pyraclostrobin and Epoxiconazole were studied in groundnut plant. Combinational fungicide formulation (18.3% w/v SE - Suspo-emulsion) containing Pyraclostrobin 13.3 % w/v and Epoxiconazole 5.0 % w/v as active contents. The Fungicide formulation was applied on groundnut plant thrice at T1 - 750 ml ha -1 and T2 - 1500 ml ha -1 with an interval of ten to twenty days between each application. The persistence of fungicide residues on groundnut plant was also studied by periodically collecting the leaf samples following one single foliar spray application of the formulation. Residues of Pyraclostrobin and Epoxiconazole were quantified using a validated high performance liquid chromatography with Ultra Violet detector (HPLC-UV) at a wave length of 230 nm, flow rate is 1.0 ml/min, Oven temperature is 30°C, mobile phase is acetonitrile: 0.1% Formic acid acid (70:30 (v/v)) and Phenomenex RP-18 (25 cm length x 4.6 mm i.d) column was used. The method has the limit of detection 0.01 mg L -1 and the limit of quantification (LOQ) 0.03 mg L -1 based on signal to noise ratio 3:1 and 10:1 respectively for all the molecules investigated. The residues of Pyraclostrobin and Epoxiconazole on groundnut plant dissipated to below the detectable level by tenth day. The DT50 (Half Life) of Pyraclostrobin and Epoxiconazole calculated by regression analysis from the dissipation data. The calculated half-life values are 2.84, 3.09 days in T1 Dose and 2.88, 3.11 days in T2 Dose respectively.
Keywords
Pyraclostrobin; Epoxi- conazole; Dissipation; DT50; Residues and Groundnut plant; HPLC-UV