Determination of imazethapyr residues in soil and grains after its application to soybeans

Abstract

Imazethapyr is widely used in soybean, and leguminous crops for control of wide variety of broad leaf weed species. A study was conducted to evaluate residues of imazethapyr in the soil and soybean grain at five different locations in India. Imazethapyr was applied at 100 g/ha, as a post emergence herbicide to control weeds in soybean fields. Residues of imazethapyr were found in the range from 0.006 to 0.018 µg/g in the soybean grains samples in all five locations. However in the soil, residues were found to be below 0.0010 µg/g in four locations, and 0.0015 µg/g in one location. Less residues were found in soils as compared to plant samples. Based on this study a pre-harvest interval of 90-102 days is suggested for soybean crops after imazethapyr application. This indicates the judicious use of imazethapyr by farmers in soybean fields.

Dissipation kinetics of glyphosate in tea and tea-field under northwestern mid-hill conditions of India

“…Data on the rate of degradation are extremely important as they permit prediction of the levels likely to remain in the soil and allow assessment of the risk associated with exposure, [8][9][10][11][12] and contamination of tea leaves. On degradation, glyphosate yields, AMPA (amino methyl phosphonic acid) a major metabolite of glyphosate which finally degrades and mineralizes to CO 2 .…”

Introduction of imidazolinone herbicide and Clearfield® rice between weedy rice—control efficiency and environmental concerns

“…Experiments and reports on the availability of IMI-herbicides in sandy soils revealed that approximately 50% of herbicides were broken and drained following two days of extensive ultraviolet light (UV) (Aichele and Penner 2005). Consequently, it was observed that continuous monitoring is a suitable technique for determining residues in both water and soil (Table 6) Generally, IMI-herbicides are weakly adsorbed by the soil's components, which eases their movement through plants, causing serious contamination (Sondhia et al 2015). This movement is affected by the soils' impurities, organic matter, clay percentages, and pH.…”

“…As an example, one of these factors is the soil composition (the soil texture), which is a physical item determined by the percentage of sand, silt, and clay in the soil body. Sondhia et al (2015) reported that IMI-herbicides persisted for a longer period in Romanian soil and demonstrated residual effects on the next crop rotation after two to three years. (Table 7) summarizes the studies exploring the different depths which IMI-herbicides could leach into; here, it is revealed that the translocation and leaching of IMIherbicide components between soil particles and the continuation of IMI-herbicides at diverse depths in the soil may increase their persistence, possibly due to the lower temperature at greater depths, less solar radiation, and the decreased activity of microorganisms in the soil (Refatti et al 2017).…”

“…There are a number of methods that were proposed to determine the extraction of IMI from the soil. To understand this, the water solubility of IMI is generally relatively high (Sondhia et al, 2015), but the PKa for each is relatively low. This solubility of IMI-herbicides in water helps to determine the leaching potential at different depths, where the pKa values of the IMIherbicides are 1.3-3.9 (Martins et al 2014).…”

Weed Management in Black Gram (Vigna mungo L.) and Residual Effect of Herbicides on Succeeding Mustard (Brasica juncea L.) Crop

“…They observed that residues were below the detectable limit in all the harvest samples (soil, plant and seed) irrespective of treatments and found completely safe for the blackgram crop at Mohanpur. Sondhia et al, (2015) reported that imazethapyr was applied at 100 g/ha, as a post emergence herbicide to control weeds in soybean fields. Residues of imazethapyr were found in the range from 0.006 to 0.018 μg/g in the soybean grains samples in all five locations.…”