Biochemical impacts of some organophosphorus insecticides on cabbage plants

ABSTRACT

The side effect of certain organophosphorus pesticides on some biochemical aspects of cabbage plants was studied. At growth period of two months, the field grown plants were treated with the pesticides malathion, pirimiphos methyl and prothiofos. The investigated insecticides were used at the recommended doses and the spray was repeated three times at interval of one month. After each spray, randomized samples were taken after 0, one and two weeks of application and biochemically analyzed. The obtained results could be summarized as follows 1-Chlorophyll analysis showed no significant variation after the first application. While continuous reduction was recorded after the second and third treatment. 2- Sugars and carbohydrates content were deplated in the treated cabbage leaves after the consequent application with the studied pesticidal chemicals. Malathion induced the maximum decline followed by prothiofos and pirimiphos-methyl. 3- Free amino acids exhibited different responses as far as the individual impact of the used chemicals was considered. Total proteins content showed an increase after the first application in response to both malathion and prothiofos. However, all the used pesticides decreased proteins content of the treated cabbage leaves after the second and third application. 4- Elemental analysis revealed that N was declined after the second and third spray in particular as a function of the sprayed materials. On the other hand P content was enhanced in the treated cabbage leaves in response to all the studied pesticides. K recorded no fixed trend after the different applications with respect to the influence of the individual chemicals