تعيين دوره بحراني كنترل علف هاي هرز آفتابگردان ( Helianthus annuus ) در منطقه مباركه اصفهان

Determination of Critical Period of Weed Control in Sunflower (Helianthus annuus cv. Sandra) in Mobarekeh Esfahan Region

ﺑﻪ ﻣﻨﻈﻮر ﺗﻌﯿﯿﻦ دوره ﺑﺤﺮاﻧﯽ ﮐﻨﺘﺮل ﻋﻠﻒ ﻫﺎيﻫﺮز آﻓﺘﺎﺑﮕﺮدان ).Helianthus annuus L( رﻗﻢ ﺳﺎﻧﺪرا، در ﺷﻬﺮﺳﺘﺎن ﻣﺒﺎرﮐﻪ، اﺳﺘﺎن اﺻﻔﻬﺎن آزﻣﺎﯾﺸﯽ در ﺳﺎل زراﻋﯽ 1391-92 در ﻗﺎﻟﺐ ﻃﺮح ﺑﻠﻮكﻫﺎي ﮐﺎﻣﻞ ﺗﺼﺎدﻓﯽ ﺑﺎ 14 ﺗﯿﻤﺎر و ﺳﻪ ﺗﮑﺮار اﺟﺮا ﺷﺪ. ﺗﯿﻤﺎرﻫﺎ ﺑﺮ اﺳﺎس روزﻫﺎي ﭘﺲ از ﺳﺒﺰ ﺷﺪن آﻓﺘﺎﺑﮕﺮدان در دو ﮔﺮوه ﺗﯿﻤﺎري ﮐﻨﺘﺮل و ﺗﺪاﺧﻞ ﻋﻠﻒﻫﺎيﻫﺮز ﺗﻌﯿﯿﻦ ﺷﺪﻧﺪ. در ﮔﺮوه اول، ﺣﺬف ﻋﻠﻒﻫﺎيﻫﺮز ﺗﺎ 50 ،40 ،30 ،20 ،10 و 60 روز ﭘﺲ از ﺳﺒﺰ ﺷﺪن آﻓﺘﺎﺑﮕﺮدان و ﺳﭙﺲ ﺣﻔﻆ آنﻫﺎ اﻋﻤﺎل ﮔﺮدﯾﺪ و در ﮔﺮوه دوم، ﺣﻔﻆ آﻟﻮدﮔﯽ ﺑﻪ ﻋﻠﻒﻫﺎيﻫﺮز ﺗﺎ ﻣﺮاﺣﻞ ﻓﻮق و ﺳﭙﺲ ﺣﺬف آنﻫﺎ اﻋﻤﺎل ﺷﺪ. دو ﺗﯿﻤﺎر ﺷﺎﻫﺪ ﺗﺪاﺧﻞ و ﮐﻨﺘﺮل ﺗﻤﺎم ﻓﺼﻞ ﻧﯿﺰ در ﻧﻈﺮ ﮔﺮﻓﺘﻪ ﺷﺪ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ ﺑﺎ اﻓﺰاﯾﺶ ﻃﻮل دورهﻫﺎي ﺗﺪاﺧﻞ ﻋﻠﻒﻫﺎيﻫﺮز ﻋﻤﻠﮑﺮد داﻧﻪ، ﻋﻤﻠﮑﺮد روﻏﻦ، ﺗﻌﺪاد داﻧﻪ در ﻃﺒﻖ و وزن ﻫﺰار داﻧﻪ ﮐﺎﻫﺶ ﻣﻌﻨﯽداري ﯾﺎﻓﺖ و ﺑﺎ اﻓﺰاﯾﺶ ﻃﻮل دورهﻫﺎي ﮐﻨﺘﺮل اﯾﻦ ﺻﻔﺎت اﻓﺰاﯾﺶ ﻣﻌﻨﯽداري ﭘﯿﺪا ﮐﺮد. ﺑﺎ اﻓﺰاﯾﺶ ﻃﻮل دورهﻫﺎي ﺗﺪاﺧﻞ ﻋﻠﻒﻫﺎيﻫﺮز، وزن ﺧﺸﮏ ﻋﻠﻒ ﻫﺎيﻫﺮز اﻓﺰاﯾﺶ ﻣﻌﻨﯽداري ﭘﯿﺪا ﮐﺮد وﺗﺮاﮐﻢ ﻋﻠﻒﻫﺎيﻫﺮز اﺑﺘﺪا اﻓﺰاﯾﺶ و ﺳﭙﺲ ﮐﺎﻫﺶ ﯾﺎﻓﺖ. ﺑﺎ اﻓﺰاﯾﺶ ﻃﻮل دورهﻫﺎي ﮐﻨﺘﺮل، وزن ﺧﺸﮏ ﻋﻠﻒﻫﺎيﻫﺮز و ﺗﺮاﮐﻢ آﻧﻬﺎ ﮐﺎﻫﺶ ﻣﻌﻨﯽداري ﯾﺎﻓﺖ. دوره ﺑﺤﺮاﻧﯽ ﮐﻨﺘﺮل ﻋﻠﻒ ﻫﺎيﻫﺮز ﺑﺮاي آﻓﺘﺎﺑﮕﺮدان ﺑﺎ در ﻧﻈﺮ ﮔﺮﻓﺘﻦ ﮐﺎﻫﺶ ﻣﺠﺎز 10 درﺻﺪ ﻋﻤﻠﮑﺮد داﻧﻪ، 12 ﺗﺎ 40 روز ﭘﺲ از ﺳﺒﺰ ﺷﺪن آﻓﺘﺎﺑﮕﺮدان )ﻣﺮﺣﻠﻪ 4 ﺑﺮﮔﯽ ﺗﺎ ﮔﻠﺪﻫﯽ( ﺗﻌﯿﯿﻦ ﺷ

In order to determine the critical period of weed control in sunflower (Helianthus annuus L. cv. Sandra) a field study was conducted in the Mobarakeh region during 2013. The experiment was carried out in a randomized complete blocks design with three replications. Treatments were based on the days after emergence of sunflower in two series. The first series consisted of weed removal, 10, 20, 30, 40, 50 and 60 days after sunflower emergence and then weed maintained until harvest. The second series consisted of weed maintaining till mentioned stages and then weed removal until harvest. Also, two control treatments (weed free and weed infested for all of the growth season) were applied. Results showed that with increasing period of weed interference, grain yield, oil yield, seed number per head and 1000 seed weight decreased significantly. Increasing period of weed control, above characteristics increased significantly. Increasing period of weed interference, weed dry weight significantly increased, but weed density first increased and then decreased. With increasing period of weed control, weed dry weight and density significantly reduced. Considering 10% acceptable grain yield losses, the critical period of weed control of sunflower was determined to be 12-40 days after emergence (between 4 leaves and flowering stage).