كليدواژه :
ﺗﺮﮐﯿﺒﺎت ﻓﺮار , ﺷﺎﺧﺺﻫﺎي ﻓﯿﺰﯾﻮﻟﻮژﯾﮑﯽ , ﺷﺪت ﺑﯿﻤﺎري , Sclerotium rolfsii
چكيده فارسي :
ﯿﻤﺎري ﭘﻮﺳﯿﺪﮔﯽ ﺳﻔﯿﺪ ﺳﺎﻗﻪ ﺑﺎ ﻋﺎﻣﻞ Sclerotium rolfsii ﯾﮑﯽ از ﻣﻬﻢﺗﺮﯾﻦ ﺑﯿﻤﺎريﻫﺎي ﺧﺎكزاد ﺑﺎدام زﻣﯿﻨﯽ اﺳﺖ ﮐﻪ در ﺳﻄﺢ وﺳﯿﻌﯽ از ﻣﺰارع ﮐﺸﺖ ﺑﺎدام زﻣﯿﻨﯽ اﺳﺘﺎن ﮔﯿﻼن ﺑﻪوﯾﮋه در زﻣﺎن ﺑﺮداﺷﺖ ﺷﺎﯾﻊ ﻣﯽﺷﻮد. ﺑﻪﮐﺎرﮔﯿﺮي ﻣﯿﮑﺮوارﮔﺎﻧﯿﺴﻢﻫﺎي ﻣﻔﯿﺪ، روش ﺟﺎﯾﮕﺰﯾﻦ ﺑﺮاي اﺳﺘﻔﺎده از ﻗﺎرچﮐﺶﻫﺎي ﺷﯿﻤﯿﺎﯾﯽ اﺳﺖ. در اﯾﻦ ﭘﮋوﻫﺶ اﺛﺮ ﺳﻪ ﺟﺪاﯾﻪ از .Trichoderma spp، ﺳﻪ ﺟﺪاﯾﻪ از .Penicillium spp، دو ﺟﺪاﯾﻪ از .Aspergillus spp و ﯾﮏ ﺟﺪاﯾﻪ از Cladosporium cladosporioides روي ﺑﯿﻤﺎرﮔﺮ S.rolfsii ﺑﺎ اﺳﺘﻔﺎده از روشﻫﺎي ﮐﺸﺖ ﻣﺘﻘﺎﺑﻞ، ﮐﺸﺖ روي اﺳﻼﯾﺪ، ﻣﺘﺎﺑﻮﻟﯿﺖﻫﺎي ﻓﺮار و ﻣﺘﺎﺑﻮﻟﯿﺖﻫﺎي ﻏﯿﺮﻓﺮار در آزﻣﺎﯾﺸﮕﺎه ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮار ﮔﺮﻓﺖ. در آزﻣﺎﯾﺶﻫﺎي ﮔﻠﺨﺎﻧﻪاي، ﮔﯿﺎﻫﺎن ﺑﺎدام زﻣﯿﻨﯽ ﺑﺎ اﯾﻦ ﺟﺪاﯾﻪﻫﺎي ﻗﺎرﭼﯽ ﻫﻤﺮاه ﺑﺎ .S
rolfsii ﻣﺎﯾﻪزﻧﯽ ﺷﺪﻧﺪ و ﺻﻔﺎﺗﯽ ﻣﺎﻧﻨﺪ ﺷﺪت ﺑﯿﻤﺎري، ارﺗﻔﺎع، وزن ﺗﺮ و وزن ﺧﺸﮏ ﮔﯿﺎه ﻣﻮرد ﻣﻄﺎﻟﻌﻪ ﻗﺮار ﮔﺮﻓﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ در روش ﮐﺸﺖ ﻣﺘﻘﺎﺑﻞ، T. harzianum و T. virens ﺑﻪ ﺗﺮﺗﯿﺐ ﺑﺎ 93/58 درﺻﺪ و 92/94 درﺻﺪ ﺑﯿﺸﺘﺮﯾﻦ ﺗﻮاﻧﺎﯾﯽ را در ﻣﻬﺎر رﺷﺪ ﻣﯿﺴﻠﯿﻮﻣﯽ S. rolfsii داﺷﺘﻨﺪ. در روش ﮐﺸﺖ اﺳﻼﯾﺪ، ﺗﻤﺎﻣﯽ ﺟﺪاﯾﻪﻫﺎ ﺑﻪﺟﺰ T. virens و T. viride در ﻣﻬﺎر رﯾﺴﻪﻫﺎي S. rolfsii ﻣﻮﻓﻖ ﺑﻮدﻧﺪ. در آزﻣﻮن ﻣﺘﺎﺑﻮﻟﯿﺖ ﻓﺮار، P. glabrum و A. flavus ﺑﻪﺗﺮﺗﯿﺐ ﺑﺎ 81/25 درﺻﺪ و 75 درﺻﺪ و در آزﻣﻮن ﻣﺘﺎﺑﻮﻟﯿﺖ ﻏﯿﺮﻓﺮار T. harzianum و T. viride ﺑﻪﺗﺮﺗﯿﺐ ﺑﺎ 97/5 و 93/75 درﺻﺪ ﺑﯿﺸﺘﺮﯾﻦ ﺗﻮاﻧﺎﯾﯽ را در ﻣﻬﺎر رﺷﺪ ﻣﯿﺴﻠﯿﻮﻣﯽ .S
rolfsii ﻧﺸﺎن دادﻧﺪ. ﻫﻤﭽﻨﯿﻦ اﺛﺮات اﯾﻦ ﻗﺎرچﻫﺎ روي ﻣﯿﺰان ﻣﻬﺎر ﺑﯿﻤﺎرﮔﺮ S. rolfsii در ﻣﻄﺎﻟﻌﺎت ﮔﻠﺨﺎﻧﻪاي ﻣﻮرد ﺑﺮرﺳﯽ ﻗﺮارﮔﺮﻓﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﮐﻪ P. glabrum ﺑﺎ 39/4 درﺻﺪ و T. viride ﺑﺎ 38/8 درﺻﺪ ﻣﻮﺛﺮﺗﺮﯾﻦ ﻗﺎرچﻫﺎ در ﮐﺎﻫﺶ وﻗﻮع و ﺷﺪت ﺑﯿﻤﺎري ﺑﻮدﻧﺪ. ﻫﻤﭽﻨﯿﻦ ﺑﻪﮐﺎرﮔﯿﺮي اﯾﻦ ﻗﺎرچﻫﺎي آﻧﺘﺎﮔﻮﻧﯿﺴﺖ در ﺷﺮاﯾﻂ ﮔﻠﺨﺎﻧﻪ ﻣﻨﺠﺮ ﺑﻪ اﻓﺰاﯾﺶ ارﺗﻔﺎع ﺑﻮﺗﻪ، وزن ﺗﺮ و ﺧﺸﮏ اﻧﺪام ﻫﻮاﯾﯽ و رﯾﺸﻪ در ﺣﻀﻮر ﻗﺎرچ ﻋﺎﻣﻞ ﺑﯿﻤﺎري ﮔﺮدﯾﺪ. ﺗﺠﺰﯾﻪ وارﯾﺎﻧﺲ و ﻣﻘﺎﯾﺴﻪ ﻣﯿﺎﻧﮕﯿﻦ ﺻﻔﺎت ﺑﺎ اﺳﺘﻔﺎده از روش ﺣﺪاﻗﻞ اﺧﺘﻼف ﻣﻌﻨﯽدار )LSD(، اﺧﺘﻼف ﻣﻌﻨﯽداري ﺑﯿﻦ ﻗﺎرچﻫﺎي ﻣﻮرد ﻣﻄﺎﻟﻌﻪ در روشﻫﺎي آزﻣﺎﯾﺸﮕﺎﻫﯽ و ﮔﻠﺨﺎﻧﻪاي را A. flavus ،P. glabrum،T. harzianum ،T. viride ﻧﺸﺎن داد. ﻧﺘﺎﯾﺞ اﯾﻦ ﺗﺤﻘﯿﻖ ﻧﺸﺎندﻫﻨﺪه اﯾﻦ ﻣﻄﻠﺐ ﺑﻮد ﮐﻪ ﻗﺎرچﻫﺎي و C. cladosporioides ﻣﻮﺟﻮد در زﯾﺴﺘﮕﺎن ﻃﺒﯿﻌﯽ ﮔﯿﺎه ﺑﺎدام زﻣﯿﻨﯽ ﺧﻮاص ﺑﺎﻟﻘﻮهاي ﺑﺮاي ﻣﻬﺎر زﯾﺴﺘﯽ ﺑﯿﻤﺎري ﭘﻮﺳﯿﺪﮔﯽ ﻔﯿﺪ ﺳﺎﻗﻪ ﺑﺎدام زﻣﯿﻨﯽ از ﺧﻮد ﻧﺸﺎن ﻣﯽدﻫﻨﺪ
چكيده لاتين :
Background and Objectives
White stem rot caused by Sclerotium rolfsii is a soilborne disease which is extensively common across the groundnut farms of Guilan province, especially during the harvest period. Using the beneficial microbial agents is an alternative method for applying the chemical fungicides.
Materials and Methods
To find the appropriate fungal antagonistic isolates for the biological control of peanut white stem rot, the effect of three isolates of Trichoderma spp., three isolates of Penicillium spp., two isolates of Aspergillus spp. and one isolate of Cladosporium cladosporioides were studied on S. rolfsii in vitro using dual culture, slide culture, volatile metabolites and non-volatile metabolites. Peanut plants were inoculated with these fungal isolates as well as S. rolfsii in greenhouse experiments, and parameters including disease severity, height, fresh weight, and dry weight of the plant were measured.
Results
The results showed that in the dual culture method, T. harzianum and T. virens were most capable of suppressing the mycelial growth of S. rolfsii with a suppression capability of 93.58% and 92.94%, respectively. In the slide culture method, all isolates turned out to be effective in suppressing the mycelia growth of S. rolfsii, except for T. virens and T. viride. In the volatile metabolite assay, P. glabrum and A. flavus with 81.25% and 75%, respectively and in the non-volatile metabolite method, T. harzianum and T. viride with 93.75% and 97.5% respectively showed the greatest ability to inhibit S. rolfsii mycelial growth. Moreover, the effects of these fungi on the control of S. rolfsii pathogen were explored in greenhouse trials. The results revealed that P. glabrum was 39.4% effective and T. viride was 38.8% effective in reducing the extent and intensity of the disease. Under the presence of the pathogen, the treatment of these antagonistic fungi in greenhouse conditions enhanced plant height, shoot and root fresh and dry weight. In the in vitro and greenhouse approaches, an analysis of
variance and a comparison of means of the attributes using the least significant difference (LSD) indicated significant differences (P ≤0.01 and P≤ 0.05) among the examined fungi.
Discussion
The results of the in vitro and greenhouse trials showed that T. viride, T. harzianum, P. glabrum, A. flavus, and C. cladosporioides, which are present in the natural flora of groundnuts, have the potential capability of the biological control of S. rolfsii as the pathogen of groundnut stem white rot.
