ارزﯾﺎﺑﯽ ﮐﺎراﯾﯽ ﺑﺮﺧﯽ از ﻋﻠﻔﮑﺶ ﻫﺎي ﭘﺲ روﯾﺸﯽ ﺑﺮ ﻋﻠﻒ ﻫﺎي ﻫﺮز و ﺧﺼﻮﺻﯿﺎت زراﻋﯽ ذرت ﻋﻠﻮﻓﻪ ايZea mays ﻫﯿﺒﺮﯾﺪ ﺳﯿﻨﮕﻞ ﮐﺮاس- 704

Effect of Post-Emergence Herbicides on Weeds and Agronomical characteristics of Forage Maize Hybrid S.C-704

ﻋﻠﻒ ﻫﺎي ﻫﺮز ﯾﮑﯽ از ﻣﻬﻤﺘﺮﯾﻦ ﻣﺸﮑﻼت ﻣﺰارع ذرت ﺑﻮده وﻪ ﺑ ﻃﻮر ﻣﻌﻨﯽ داري ﺑﺎﻋﺚ ﮐﺎﻫﺶ ﻋﻤﻠﮑﺮد آﻧﻬﺎ، ﻣﯽ ﺷﻮﻧﺪ. آزﻣﺎﯾﺶ زراﻋﯽ در ﺳﺎل 1391 ﺑﻪ ﻣﻨﻈﻮر ﺑﺮرﺳﯽ ﺗﺄﺛﯿﺮ ﻋﻠﻒ ﮐﺶ ﻫﺎ ﺑﺮ ﻋﻠﻒ ﻫﺎي ﻫﺮز و ﺧﺼﻮﺻﯿﺎت زراﻋﯽ ذرت اﻧﺠﺎم ﺷﺪ. ﺳﻪ ﻋﻠﻒ ﮐﺶ ﻣﺘﻔﺎﻪ وت ﺑ ﻧﺎم ﻫﺎي ﺗﻮﻓﻮردي آﻣﯿﻦ )ﯾﻮ46دﯾﻔﻠﻮﺋﯿﺪ(%SL72 ، رﯾﻢ ﺳﻮﻟﻔﻮرون )ﺗﯿﺘﻮس( DF25 و رﯾﻢ ﺳﻮﻟﻔﻮرون+ ﻧﯿﮑﻮﺳﻮﻟﻔﻮرون )اوﻟﺘﯿﻤﺎ(WG75% ﭘﺲ از ﺟﻮاﻧﻪ زﻧﯽ ذرت رﻗﻢ ﺳﯿﻨﮕﻞ ﮐﺮاس704 در ﻣﻨﻄﻘﻪ ﺷﺎزﻧﺪ ﻣﻮرد اﺳﺘﻔﺎده ﻗﺮار ﮔﺮﻓﺖ. ﺗﯿﻤﺎر آزﻣﺎﯾﺸﯽ در ﻗﺎﻟﺐ ﻃﺮح ﺑﻠﻮك ﻫﺎي ﮐﺎﻣﻞ ﺗﺼﺎدﻓﯽ ﺑﺎ 3 ﺗﮑﺮار در ﮐﺮت ﻫﺎﯾﯽ ﺑﺎ اﺑﻌﺎد 18 ﻣﺘﺮﻣﺮﺑﻊ اﻧﺠﺎم ﺷ.ﺪ ﺣﺪاﮐﺜﺮ و ﺣﺪاﻗﻞ ﺗﺮاﮐﻢ ﻋﻠﻒ ﻫﺎي ﻫﺮز )39/33 و 11 ﺑﻮﺗﻪ در ﻣﺘﺮﻣﺮﺑﻊ( ﺑﻪ ﺗﺮﺗﯿﺐ در ﺗﯿﻤﺎرﻫﺎي ﺷﺎﻫﺪ ﺑﺪون ﮐﻨﺘﺮل و ﯾﮏ ﻣﺮﺣﻠﻪ وﺟﯿﻦ ﺛﺒﺖ ﮔﺮدﯾﺪ.ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﺎرﺑﺮد ﻋﻠﻒ ﮐﺶ ﺗﺮاﮐﻢ ﻋﻠﻒ ﻫﺎي ﻫﺮز را ﮐﺎﻫﺶ داد و ﺗﺄﺛﯿﺮ ﻣﺜﺒﺘﯽ در ﻋﻤﻠﮑﺮد ﻋﻠﻮﻓﻪ در ﻣﻘﺎﯾﺴﻪ ﺑﺎ ﺗﯿﻤﺎر ﺷﺎﻫﺪ ﺑﺪون ﮐﻨﺘﺮل داﺷ.ﺖ در اﯾﻦ آزﻣﺎﯾﺶ ﻋﻠﻒ ﮐﺶ ﺗﺮﮐﯿﺒﯽ رﯾﻢ ﺳﻮﻟﻔﻮرون+ ﻧﯿﮑﻮﺳﻮﻟﻔﻮرون و رﯾﻢ ﺳﻮﻟﻔﻮرون اﺛﺮﺑﺨﺸﯽ ﺑﯿﺸﺘﺮي ﻧﺴﺒﺖ ﺑﻪ ﺗﯿﻤﺎر ﻋﻠﻒ ﮐﺶ ﺗﻮﻓﻮردي داﺷﺘﻨﺪ. وزن ﺧﺸﮏ ﻋﻠﻒ ﻫﺎﯾﻬﺮز در ﺗﯿﻤﺎرﻫﺎي ﯾﮏ ﻣﺮﺣﻠﻪ وﺟﯿﻦ، ﮐﺎرﺑﺮد ﻋﻠﻒ ﮐﺶ ﻫﺎي اوﻟﺘﯿﻤﺎ و رﯾﻢ ﺳﻮﻟﻔﻮرون ﻧﺴﺒﺖ ﺑﻪ ﺗﯿﻤﺎر ﺷﺎﻫﺪ ﺑﻪ ﺗﺮﺗﯿﺐ ،96 75/4و 42 درﺻﺪ ﮐﺎﻫﺶ ﯾﺎﻓﺖ. ﻫﻤﭽﻨﯿﻦ ﺑﯿﺸﺘﺮﯾﻦ ﻋﻤﻠﮑﺮد ﻋﻠﻮﻓﻪ ﻣﻌﺎدل 57/77 ﺗﻦ در ﻫﮑﺘﺎر ﺑﻪ ﺗﯿﻤﺎر رﯾﻢ ﺳﻮﻟﻔﻮرون ﺗﻌﻠﻖ داﺷﺖ ﮐﻪ ﺑﺎ ﺗﯿﻤﺎرﻫﺎي ﯾﮏ ﻣﺮﺣﻠﻪ وﺟﯿﻦ و ﺗﯿﻤﺎر ﺗﺮﮐﯿﺒﯽ رﯾﻢ ﺳﻮﻟﻔﻮرون+ ﻧﯿﮑﻮﺳﻮﻟﻔﻮرون در ﯾﮏ ﮔﺮوه آﻣﺎري ﻗﺮار ﮔﺮﻓﺘﻨﺪ، در ﺣﺎﻟﯽ ﮐﻪ ﻋﻤﻠﮑﺮد ﻋﻠﻮﻓﻪ در ﺗﯿﻤﺎر ﺗﻮﻓﻮردي ﻣﻌﺎدل 50/55 ﺗﻦ در ﻫﮑﺘﺎر ﺑ.ﻮد رﯾﻢ ﺳﻮﻟﻔﻮرون ﺑﺎﻋﺚ اﻓﺰاﯾﺶ 27/13 درﺻﺪي ﻋﻤﻠﮑﺮد ﻋﻠﻮﻓﻪ ﻧﺴﺒﺖ ﺑﻪ ﺗﯿﻤﺎر ﺷﺎﻫﺪ ﺷﺪ.

Weeds are a one of the major problems in maize and significantly decrease grain yield of maize. Field experiment was carried out during 2012 to identify weed species and to investigate the efficacy of herbicides on weeds and their effect on Agronomical characteristics. Three different herbicides were applied after maize emergence, namely U-46 difloied herbi (2,4-D-dimetil ammonium), Titus (Rimsolfuron) and Oltima (Nimsolfuron+ Nicosolfuron) in the maize variety SC-704 in Shazand region, Iran. The experimental treatments were set in a randomized complete block design with three replications with a plot size of 18 m2. Maximum and minimum weed density (39.33 and 11 m-2) was recorded for weedy check and once hand weeding treatments, respectively. Results showed that herbicide application reduced the weed density and positively affected the forage yield in comparison to an untreated control. Oltima (Rimsolfuron+Nicosolfuron), Nimsolfuron proved most efficient as compared to 2,4-D dimetil ammonium. Also once hand weeding, application of Oltima and Nimsolfuron could be decreased of the weeds dry weight by 96, 75.4 and 42% as compared to weedy check, respectively. Comparatively high forage yields (57.77 t.ha-1) were found in plots treated with Rimsolfuron that with treatment of weeding hand along with Rimsolfuron+ Nicosolfuron was in same group, while the forage yield in 2,4-D-dimetil ammonium treated plots was 50.55 t ha-1, respectively. The application of Rimsolfuron could be increased forage yield by 27.13% as compared to control treatment.