ﭘﯿﺶﺑﯿﻨﯽ ﻇﻬﻮر ﮔﯿﺎﻫﭽﻪ ﻋﻠﻒﻫﺎي ﻫﺮز ﻫﻔﺖﺑﻨﺪ ﭘﯿﭽﮑﯽ، ﺷﺎﻫﺘﺮه و ﭘﯿﭽﮏ ﺻﺤﺮاﯾﯽ ﺑﺎ اﺳﺘﻔﺎده از ﻣﺪلﻫﺎي دﻣﺎﯾﯽ در ﺷﺮاﯾﻂ ﮐﺮج

Predicting of Wild buckwheat, Alkafaun and Field Bindweed Seedling Emergence with Using Thermal Model in Karaj

ﭘﯿﺶﺑﯿﻨﯽ زﻣﺎن روﯾﺶ ﻋﻠﻒﻫﺎي ﻫﺮز از ﻃﺮﯾﻖ ﺑﻬﯿﻨﻪ ﺳﺎزي زﻣﺎن ﮐﻨﺘﺮل ﻣﯽﺗﻮاﻧﺪ در ﮐﺎﻫﺶ ﻣﺼﺮف ﻋﻠﻒﮐﺶﻫﺎ ﻣﻮﺛﺮ ﺑﺎﺷﺪ. ﺟﻬﺖ ﭘﯿﺶﺑﯿﻨﯽ زﻣﺎن ﻇﻬﻮر ﮔﯿﺎﻫﭽﻪﻫﺎي ﻫﻔﺖﺑﻨﺪ ﭘﯿﭽﮑﯽ ).Polygonum convolvulus L(، ﺷﺎﻫﺘﺮه ) Fumaria vaillantii Lois( و ﭘﯿﭽﮏ ﺻﺤﺮاﯾﯽ ).Convolvulus arvensis L( ﺑﺎ اﺳﺘﻔﺎده از ﻣﺪلﻫﺎي دﻣﺎﯾﯽ، آزﻣﺎﯾﺸﯽ در ﻓﺼﻞ زراﻋﯽ 1392-1391 در ﻣﺰرﻋﻪ ﺗﺤﻘﯿﻘﺎﺗﯽ ﭘﺮدﯾﺲ ﮐﺸﺎورزي داﻧﺸﮕﺎه ﺗﻬﺮان اﺟﺮا ﮔﺮدﯾﺪ. ﺑﺮ اﺳﺎس ﻧﺘﺎﯾﺞ ﺑﺪﺳﺖ آﻣﺪه از ﺗﺎﺑﻊ ﻟﺠﺴﺘﯿﮏ ﺳﻪ ﭘﺎراﻣﺘﺮه 50 درﺻﺪ روﯾﺶ ﻧﻬﺎﯾﯽ ﻫﻔﺖﺑﻨﺪ ﭘﯿﭽﮑﯽ در ﺣﺎﺷﯿﻪ داﺧﻠﯽ، ﻣﺮﮐﺰ و ﺣﺎﺷﯿﻪ ﺧﺎرﺟﯽ ﺑﻪ ﺗﺮﺗﯿﺐ ﺑﺎ درﯾﺎﻓﺖ 75/21 و 71/48 و 75/21 درﺟﻪ روز رﺷﺪ ﺣﺎﺻﻞ ﺷﺪ. ﺷﺎﻫﺘﺮه در ﺣﺎﺷﯿﻪ ﺧﺎرﺟﯽ ﻣﺰرﻋﻪ ﻧﺮخ روﯾﺶ ﭘﺎﯾﯿﻦﺗﺮي را ﺑﻪ ازاء درﺟﻪ روز رﺷﺪ درﯾﺎﻓﺘﯽ ﻧﺴﺒﺖ ﺑﻪ ﺳﺎﯾﺮ ﻣﻨﺎﻃﻖ از ﺧﻮد ﻧﺸﺎن داد، ﯾﻌﻨﯽ ﺑﺎ اﻓﺰاﯾﺶ ﻫﺮ واﺣﺪ درﺟﻪ روز رﺷﺪ ﺗﻌﺪاد ﮔﯿﺎﻫﭽﻪ ﮐﻤﺘﺮي ﻧﺴﺒﺖ ﺑﻪ ﺳﺎﯾﺮ ﻣﻨﺎﻃﻖ ﻣﺰرﻋﻪ ﺑﻪ ﺳﻄﺢ ﺧﺎك آﻣﺪﻧﺪ. اﯾﻦ در ﺣﺎﻟﯽ ﺑﻮد ﮐﻪ 50 درﺻﺪ روﯾﺶ ﻧﻬﺎﯾﯽ ﺷﺎﻫﺘﺮه در ﻣﺮﮐﺰ و ﺣﺎﺷﯿﻪ داﺧﻠﯽ ﻣﺰرﻋﻪ ﺑﻪ ﺗﺮﺗﯿﺐ ﺑﺎ درﯾﺎﻓﺖ 45/90 و 49/11 درﺟﻪ روز رﺷﺪ ﺣﺎﺻﻞ ﺷﺪ. ﭘﯿﭽﮏ ﺻﺤﺮاﯾﯽ در ﺣﺎﺷﯿﻪ داﺧﻠﯽ و ﻣﺮﮐﺰ ﻣﺰرﻋﻪ ﺑﺎ درﯾﺎﻓﺖ 158/98 و 150/60 درﺟﻪ روز رﺷﺪ ﺑﻪ 50 درﺻﺪ روﯾﺶ ﻧﻬﺎﯾﯽ رﺳﯿﺪ. روﻧﺪ روﯾﺶ ﻫﻔﺖ ﺑﻨﺪ ﭘﯿﭽﮑﯽ در ﻣﻨﺎﻃﻖ ﻣﺨﺘﻠﻒ ﻣﺰرﻋﻪ ﻧﺸﺎن داد ﮐﻪ اﯾﻦ ﻋﻠﻒﻫﺮز در اواﯾﻞ ﻓﺼﻞ رﺷﺪ در ﻣﺰرﻋﻪ ﺳﺒﺰ ﻣﯽﺷﻮد و اﻗﺪاﻣﺎت ﮐﻨﺘﺮل ﺑﺎﯾﺴﺘﯽ در اواﯾﻞ ﻓﺼﻞ رﺷﺪ ﺻﻮرت ﮔﯿﺮد ﺗﺎ از ﺧﺴﺎرت اﯾﻦ ﻋﻠﻒﻫﺮز در ﻣﺰرﻋﻪ ﮐﺎﺳﺘﻪ ﺷﻮد. ﺳﺒﺰ ﺷﺪن ﺷﺎﻫﺘﺮه در اواﯾﻞ ﻓﺼﻞ رﺷﺪ و از درﺟﻪ روز رﺷﺪ ﭘﺎﯾﯿﻦﺗﺮ از 50 ﺷﺮوع ﻣﯽﺷﻮد ﻟﺬا ﻋﻤﻠﯿﺎت ﮐﻨﺘﺮل ﺑﺎﯾﺴﺘﯽ در اواﯾﻞ ﻓﺼﻞ رﺷﺪ ﺻﻮرت ﮔﯿﺮد و ﺑﻪ ﺗﺎﺧﯿﺮ ﻧﯿﺎﻓﺘﺪ. ﺷﺮوع ﺳﺒﺰ ﺷﺪن ﭘﯿﭽﮏ ﺻﺤﺮاﯾﯽ از اواﺳﻂ ﺗﺎ اﻧﺘﻬﺎي ﻓﺼﻞ رﺷﺪ ﻣﯽﺑﺎﺷﺪ ﻟﺬا ﻋﻤﻠﯿﺎت ﮐﻨﺘﺮل اﯾﻦ ﻋﻠﻒﻫﺮز ﻣﯽﺗﻮاﻧﺪ ﺑﺎ ﺗﺎﺧﯿﺮ ﺑﯿﺸﺘﺮ ﺻﻮرت ﮔﯿﺮد و ﯾﺎ در اﻧﺘﻬﺎي ﻓﺼﻞ رﺷﺪ و ﭘﺲ از ﺑﺮداﺷﺖ ﻣﺤﺼﻮل آن را ﻣﺪﯾﺮﯾﺖ ﮐﺮد.

Prediction of weed emergence timing would help reduce herbicide use through the optimization of the timing of weed control. In order to predict the emergence of wild buckwheat (Polygonum convolyulus L.), alkafaun (Fumaria vaillantii Lois) and Field bindweed (Convolvulus arvensis L.) by using the temperature model, an experiment was conducted at wheat field research of university of Tehran, Karaj during 2012-13. Based on the results from logistic model, 50 percent of cumulative emergence of wild buckwheat were obtained in 75.21, 71.48 and 75.21 growing degree day at inner margin, center and outer margin of wheat field, respectively. Alkafaun had lower emergence per received GDD at outer margin in comparison with other parts of the field, that is, with the increase of each unit of GDD, fewer seedlings came to the soil surface than other areas of the field. Although emergence had lower slope per growing degree day at this part, but it was achieved to 50 percent cumulative emergence with lower received GDD. It was this time that 50 percent cumulative emergence of alkafaun achieved with 49.11 and 45.90 GDD at center and outer margin of field, respectively. Field bindweed was achieved to 50 percent of cumulative emergence with 158.98 and 150.60 growing degree day at inner margin and center of field. The process of growing seven wild buckwheat in different areas of the field showed that this weed emerges in the field early in the growing season and control measures should be taken in the early growing season to reduce the damage of this weed in the field. The emergence of alkafaun starts at the beginning of the growing season and from the degree of growth day below 50, so the control operation should be done at the beginning of the growing season and should not be delayed. The emergence of field bindweed is from the middle to the end of the growing season, so the control of this weed can be done with more delay or at the end of the growing season and after harvest.