Stunting in Growth of Cotton Seedlings by Treating Seed with The Fungicide Tebuconazole and Fludioxonil (Eleven) التقزم فى نمو بادرات القطن الناجم عن معاملة البذرة بمادتى تیبیوکونازول و فلودیوکسانیل (إلیفین)

In the course of evaluating the newly released fungicide Eleven, for controlling damping-off of cotton seedlings, a severe stunting was observed on growth of the surviving seedlings after treating seed with the fungicide. We employed a biometrical approach to demonstrate that the increase in the biosynthesis of abscisic acid (ABA) was the most likely explanation for the observed stunting. The present study also demonstrated that Eleven in itself was effective in controlling damping-off of cotton seedlings caused by Rhizoctonia solani. However, despite this efficiency, the application of Eleven for controlling the disease is not a desirable practice, due to its phytotoxic effect on growth of the surviving seedlings.