First report of the pendimethalin injury to cotton
Khalid P. Akhtar, M.A. Haq, F.F. Jamil, I.A. Khan, M. Hussain, A.I. Khan and M.K.R. Khan, Nuclear Institute for Agriculture and Biology (NIAB), PO Box 128, Faisalabad, Pakistan.
There are various physiological disorders that commonly affect cotton crops including nutrient deficiencies, phytotoxicity from pesticides, and environmental effects. Several herbicides used on cotton are capable of chemical injury when applied contrary to label instructions or under certain environmental conditions. Spray tank contamination can be a problem when farmers apply insecticides to crops with herbicide-contaminated sprayers and cotton is very sensitive to tank contamination. Pendimethalin (33% w/w) is a pre-emergent, preplant-incorporated or early post-emergence, directed dinitroaniline herbicide commonly used in Pakistan. This is the first report of injury on cotton in Pakistan from pendimethalin. This injury was the result of spraying cotton with the insecticide methamedophos (50% w/w) using a pendimethalin-contaminated sprayer. Severe distortion, puckering of leaves, elongation of bracts and lobes of leaves, decrease in lamina expansion, strapping of veins and elongation of leaf petioles were observed as characteristic symptoms of the injury.
Keywords: Gossypium hirsutum, herbicide, insecticide, phytotoxicity, pendimethalin, methamedophos.
Plant Protection Quarterly (2006) 21 (1) 5-6.