Evaluation of efficiency of new pre emergence and post emergence herbicides for weed control in apple and citrus orchards

Due to the lack of diversity of herbicides in the orchards and the proposal to eliminate some of herbicides, such as parquets, it is necessary to investigate new pre-emergence and post-emergence herbicides in orchards. These experiments were conducted in Tehran in apple and in Desfol and Jiroft in citrus orchards with 13 treatments in a completely randomized block design with 3 replications. Pre-emergence herbicides Napropamide (2.7,3.6, 4.5 kg a.i./ha) (SC 45%) and Trifluralin (1.2 kg a.i./ha )(EC 48%) and post-emergence herbicides a new Glyphosate (0.36, 0.54 kg a.i./ha)(SC 36%), 160g L-1 Amitrole, 143g L-1+ Ammonium thiocyanate + 60g L-1 Glyphosate (ATG) (2.2,2.9,3.6.4.3 kg a.i./ha) (SL 36.6%), Glyphosate (0.62 kg a.i./ha)(SL 41%), Paraquat (0.6 kg a.i./ha )(SL 20%) were the treatments. The results of the experiment showed that the napropamide in Dezful, controlled annual winter weeds 20-42 %, and in Jiroft in amounts of 3.6 and 4.45 kg a.i./ha, controlled 27 percent, while in Tehran because of perennial weeds unable to control winter weeds. Trifluralin herbicide at this time was not able to control weeds in all areas. Among post-emergence herbicides, ATG herbicides in the amounts of 3.6 and 3.6 kg a.i./ha and new glyphosate in the amount of 0.54 kg a.i./ha with paraquat and glyphosate were able to control summer weeds. According to the results of this study, it seems that the pre-emergence herbicide of napropamide at 3.6 kg a.i./ha, post- emergence herbicides ATG at 3.6 kg a.i./ha and new glyphosate at 0.54 kg a.i./ha are recommendable in orchards.