Search

Brinjal (Solanum melongena) is a versatile crop infected by several insects and pests. For the control of these pests, spiromesifen insecticide has been in use to reduce the damage and increase crop production worldwide. Therefore, a field trial was conducted to study dissipation and persistence behavior of spiromesifen 22.9% w/w SC in/on brinjal at the recommended dose (RD) 96 g a.i./ha and double to recommended dose 192 g a.i./ha (2RD). The quantitative analysis of spiromesifen was performed using ultra-high performance liquid chromatography- tandem mass spectrometry (UHPLC-MS/MS). Samples were processed by the Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) method. The analytical method was validated using various parameters viz., linearity (R2≥0.99), sensitivity (LOD and LOQ), accuracy (recovery=70-120%) and precision (RSD≤20%). The spiroemsifen persisted up to 3 days at RD and 5 days at 2RD. The dissipation half-life (DT50) of spriromesifen was 3.64 and 4.10 days at RD and 2RD in brinjal, respectively. However, residues of spiromesifen measured from soil at 0th (2 hr) day and 10th day were below the limit of quantification (BQL). The waiting period deciphered for spiromesifen applied in brinjal was 1 day at the recommended dose. Further, health risk assessment (health risk index

Sapota, a prominent and economically important fruit crop of India is susceptible to several species of insect and mite pests. Several pesticides formulations are used to control the pest damage in sapota. The present investigation was aimed to study the dissipation and persistence behaviour of combi-product profenofos 40% + cypermethrin 4% (44EC) at the standard dose (SD) (1162 g a.i. ha-1+106 g a.i. ha-1) and double to standard dose (2×SD) (2324 g a.i. ha-1+212 g a.i. ha-1) in/on sapota under tropical agro-climatic conditions of South Gujarat in India. Prior to quantitative analysis of pesticide residue on Gas chromatography with electron captured detector (GC-ECD), the modified Quick, Easy, Cheap, Effective, Rugged and Safe (QuEChERS) based method was validated on its accuracy, precision, linearity and sensitivity. Profenofos persisted in sapota up to 30 days with the half-lives of 5.65 and 7.34 days at SD and 2×SD, respectively. Cypermethrin dissipated at a rapid pace and was below quantitation limit (BQL) on 7 days at either dose of application; the half-life values recorded were 3.27 and 4.43 days at SD and 2×SD, respectively. This is the first case study that reflects 14 days as a waiting period after the last spray of combi-product (44EC) at standard dose facilitates the residue-free sapota fruits. Further, the health risk index (HRI