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Mango (Mangiferae indica L.) is an important exporthorticultural crop of India. Various insects and diseasesinfest the fruit especially in the fruiting season. The com-mon insect pests are mango leafhopper, mealy bug, leafwebber, inflorescence midge and fruit fly. The major lossof about 60% is due to leafhopper and mango leafhopper.These pests infest the mango at the floral and bud stage tofruit setting, tender leaves and small fruits. The crop pro-tection measures undertaken to control pest infestation in-volves spray of insecticides along with biological andcultural practices.India produces 65% of the world’s mango crop,9,000,000 MT, but with very little export. Although, Asiaaccounts for 75% world production, its dominance does nottranslate into international trade. The presence of pesticideremnants in mango lowers the export quality of mangofruits in the international market. To increase foreign trade,under the WTO regime, it is imperative to produce pesti-cide free mangoes.The insecticides commonly applied by the farmers areendosulfan, parathion methyl, chlorpyrifos, cypermethrinand fenvalerate. This paper presents a method for theestimation of the multi-class pesticides in mango and theirrecovery.Materials and MethodSolvents like acetone, dichloromethane, hexane (analyticalgrade), were distilled before use. Adsorbents neutral alu-mina and Florisil were activated before use. Pesticidestandards of methyl parathion, endosulfan, chlorpyrifos,cypermethrin and fenvalerate were of analytical gradequality. Gas Chromatogram instrumen-Shimadzu GC-17Afitted with an auto-sampler and ECD detector was used foranalysis. Other minor equipments required were rotaryevaporator and Waring blender, etc.Individual stock standard solutions (1,000 lg/mL) ofparathion methyl, endosulfan, chlorpyrifos, cypermethrinand fenvalerate were prepared in hexane (analytical grade).Working standard solutions of each pesticide was preparedby serial dilutions to 100 lg/mL, which was further dilutedto 0.1–10 lg/mL as per detector response. All the stocksolutions were stored at 4 C. Appropriate aliquot of indi-vidual pesticides solutions were taken and a mixture of fivepesticides of 100 lgmL

Lactofen, a member of the diphenyl ether chemical family, shows great potential for the control of broadleaf weeds associated with leguminous crops. It presents a high degree of selectivity when applied post-emergence to soybean and peanut crops. This paper presents the persistence of lactofen under a soybean crop under various conditions, including without remediation techniques, under soil solarization with polyethene sheets, and soil solarization followed by straw amendment. The results indicate that dissipation is faster when using the soil solarization technique (set II) compared to no treatment (set I) and is further enhanced by tstraw amendment, where almost 90% dissipation was recorded (set III). The dissipation followed first-order kinetics with a half-life that varied from 30 to 10 days. The half-life of lactofen was 15 days in treatments of soil solarization and straw amendments alone, indicating that both techniques have to be used in combination to achieve successful remediation of soil. Use of biodegradable polythene/substitute material will make this process a popular technique and may also improve its commercial viability.

Intensive application of organochlorine pesticides in agriculture and medicinal parasitology coupled with high stability of these pesticides in the environment resulted in their spreading all over the globe.The world over the use of HCH in agriculture has been banned . However , it is still being used in animal sheds and public health . The compulsive use of HCH is the low cost of the insecticide. Its use has recently been banned and the use of lindane is being favoured in agriculture. Lindane is the active constituent of HCH and its use should be beneficial in terms of insect control and it will not pose any environmental problem due to the accumulation of the more persistent beta isomer of HCH. Though, HCH is not used in many countries there are reports of its residues in the environment, probably caused by long range transport from other areas (Cleeman et.al 1995 ). Monitoring of vegetables ( Lal et al. 1969; Mukherjee and Gopal 1996), milk (Mukherjee and Gopal 1993) ,drinking and ground water (Gopal and Mukherjee,1999; Allchin 1991) 1 lakes ( Dua et al. 1998), fishes ((Mugachia et al.1992) have recorded the presence of HCH residues . Because of the ability of HCH to dissolve in fats they get accumulated in the adipose tissues of animals and men (Waliszewskei et.al.1995) and have also been detected in breast milk ( Barkatina et .al .1998) .

India is among a few developing countries where organochlorines are still used for controlling pests due to economic constraints. DDT and HCH are still used for controlling pests of public, health especially malaria vector. The residues of these pesticides are known to find their way into milk and milk products (Mukherjee and Gopal 1992a). In our earlier publication (Mukherjee and Gopal 1992a), baby milk food was not included, it was considered of interest to monitor baby milk food, and animal feed samples for the presence of persistent compounds (Matsumura 1975). For evaluating the level of contamination and for identification of persistent and harmful chemicals, monitoring studies are essential. Besides monitoring of baby milk food and animal feed for organochlorines, vegetables s a m ples were procured for quantifying the residues of various pesticides currently being used in Delhi and surrounding areas. The study can indicate which pesticides need to be banned or require longer waiting period.

Thiacloprid is a systemic neonicotinoid. The study hypothesized that difference may be seen in the rate of dissipation of thiacloprid when applied on non-transgenic and transgenic cabbage. Thiacloprid was estimated by HPLC. Half life of thiacloprid in transgenic as well as in normal cabbage ranged between 12.3–13.1 days in two doses of application. Under field condition, after 15 days, 59.2 % and 54.3 % dissipation was recorded at lower and higher rates of application in transgenic cabbage, where as the insecticide dissipated 57.5 % and 59.1 % for single dose and double dose application, respectively in non-transgenic cabbage. The study establishes that there is no significant difference in dissipation of a systemic pesticide in transgenic versus non-transgenic cabbage. Decontamination of thiacloprid contaminated cabbage was carried out by different chemical treatments. The application of 0.5 % NaHCO3 (an edible alkali) may be recommended for decontamination. Thiacloprid residues in the day-3 field samples of cabbage could be reduced below Japanese MRL (1.0 mg kg−1) by treating with 0.5 % NaHCO3 solution for 1 h.

The paper presents a method for residue analysis of flubendiamide in rice (Oryza sativa), which includes improved extraction, cleanup and determination of flubendiamide in rice seeds, husk and straw by using LC with UV detection. Safety evaluation of this insecticide in rice has been carried out after applying its soluble concentrate (SC) formulation at recommended dose (30 g a.i. ha(-1)) and double of the recommended dose (60 g a.i. ha(-1)) on rice crop. MRL of flubendiamide on rice grain can be proposed as 0.2 mg kg(-1).

Pigeonpea (Cajanus cajan L. Millsp) is one of the major pulse crop of India. The loss of pigeonpea crop due to pod and foliage pests is significant, the major pests being pod fly, hairy caterpillar, aphids, white fly, plume moth borer, leaf caterpillar and jassids. It is imperative to save every grain by chemical control methods but these toxicants should not leave unusually high residues on the edible parts. In this paper the authors report the residue behavior of three different insecticides namely, hexachlorocyclohexane, endosulfan and fluvalinate on this crop.