اثر تنظیم کننده های رشدگیاهی بر کاهش خسارت علف کش های انتخابی در گیاه سیر

Abstract Unsuitable concentrations of herbicides, lack of weed control and the severe damage to the plant will cause . Plant growth regulators can play a role in reducing damage . For this purpose, in shahid  Bahonar University research greenhouse two experiment was carried out in 1391. The first experiment in a completely randomized design includes selective herbicides in five level, haloxyfop (0, 3, 4, 5 and 10 per thousand), oxyfluorfen (0, 3, 4, 5 and 10 per thousand) and sethoxydim (0, 6, 8, 10 and 15 per thousand) with three replications . The second  experiment was  factorial in a completely randomized design with growth regulators and herbicides . Regulators include salicylic acid ( 0, 0.25 and 5.0 mM) ,  methyl jasmonate (0, 5 and 10 µM) and brassinosteroid  (0, 1 and 2 µM) as seed soaking and spray of  Herbicides with low concentrations (3 and 4 haloxyfop and oxyfluorfen  6 and 8 sethoxidim) and high concentration (5 haloxyfop and oxyfluorfen  and10 sethoxydim) were selected . The results showed that in the first experiment haloxyfop and oxyfluorfen to concentration of 4 and sethoxydim to 8 on growth, biomass, photosynthetic pigments, ion leakage , oxidative enzymes  had no harmful effect . In the second experiment it was revealed high concentrations of herbicides significantly reduced the growth characteristics. The combination of regulators and herbicides significantly reduced the negative effects of herbicide.according to results , Salicylic acid 0.25 mM, methyl jasmonate1 µM and  brassinosteroid5 µM were more effective.