METHOD VALIDATION AND HARVEST TIME RESIDUES OF CLOTHIANIDIN 50 WDG IN SUGARCANE USING UHPLC

Field study was conducted to assess the harvest time residues of clothianidin 50 WDG in sugarcane at Tamil Nadu Agricultural University, Coimbatore during 2016 and 2017. Clothianidin was treated as soil drenching at 200 and 400 g a.i. ha-1 at the time of planting. Sampling was done at the time of harvest. The whole plant sampling was done and canes were chopped in to small pieces, homogenized separately in a mixer grinder and used for analysis. The validation of analytical method in UHPLC was performed for specificity, linearity, Limit of Detection (LOD), Limit of quantitation (LOQ), recovery, repeatability and ruggedness along with measurement uncertainty. Method was developed and validated with the good specificity to clothianidin. Linearity was obtained with R2 value of 0.991 and with acceptable recovery range between 80 to 120 Per cent. The LOQ and LOD values for clothianidin were 0.01 and 0.003 μg g-1 for sugarcane. Satisfactory repeatability ruggerdness was ensured. In the field experiment the harvest time residues of clothianidin 50 WDG applied at 200 and 400 g a.i. ha-1 at the time of planting as soil drenching were at below detectable level (BDL). Hence, the recommended dose of clothianidin 50 WDG (200 g a.i. ha-1) at the time of planting as soil drenching will not leave any residues in the harvested cane.