Persistence and biochemical influence of carbosulfan and carbofuran on solanum tuberosum tubers under the Egyptian environmental conditions

Persistence of carbosul fan and carbofuran under the Egyptian normal field conditions when used for protecting Solanum tuberosum plant was studied. carbosulfan was used for foliar application but carbofuran was used as granulcs in soil against nematodes. The residue half life [RL50] values were 2.86 and 6.41 days for carbosulfan on plant leaves and in soil. respectively. As for carbofuran which was applied in soil. the RL50 value was 6.74 days in soil surface layer. The PHI for carbosulfan in tubers is more than 16 days after foliar application, but for carbofuran the PHI is about 30 days from tuber formation. Photo-decomposition study showed that carbosulfam degraded faster than carbofuran when exposed to direct sunlight or to short wave UV light, with RL50 of 8.14 and 20.38 hr in sunlight and 6.09. 89.41 hr in UV light for carbosulfan and carbofuran. respectively. The study included also the estimation of the amounts of carbofuran resulted from carbosulfan transformation under exposure to sunlight or to UV-light as major degradation product [or metabolite] for carbosulfan. The study of the biochemical effects on the composition of the tubers revealed that the two pesticide treatments attained no significant effect on total carbohydrates content or in total lipids content. A significant decrease in total nitrogen content anti consequently total crude protein was registered only after 7 days from carbosulfan application. Soluble protein content significantly decreased after 70 days from soil application with carbofuran but returned to the normal level after 7 days. The electrophoretic patterns of soluble protein extracted from tubers were also studied

Effect of storage temperature on the stability of chemical and physical properties of profenofos insecticide formulation [EC]

Profenofos insecticide was subjected to different storage conditions at the temperatures 54°C for 14 days, zero °C for 7 days according to FAO specifications [1998] and, in sunny place and in dark place for 360 days according to Egyptian conditions. Chemical stability of profenofos was stable if stored either at 54 °C or zero °C for 14 and 7 days, respectively conformed with Food and Agriculture Organization [FAO] specifications during periods of storage and more degradated in sunny place than in dark place. Physical properties [pH range, Emulsion stability and re-emulsification] became conformity with FAO specification