ارزيابي مقاومت به سرما در كلزا (.brassica napus l) با استفاده از شاخص‌هاي تحمل تنش

Evaluation of Cold Tolerance in Rapeseed (Brassica napus L.) Using Stress Tolerance Indices

ﺑﻪﻣﻨﻈﻮر ﺑﺮرﺳﯽ واﮐﻨﺶ 120 ژﻧﻮﺗﯿﭗ ﮐﻠﺰا )ﺷﺎﻣﻞ100 ﻫﯿﺒﺮﯾﺪ ﺑﻪﻫﻤﺮاه 20 واﻟﺪ( از ﻟﺤﺎظ ﺗﺤﻤﻞ ﺗﻨﺶ ﺳﺮﻣﺎ، آزﻣﺎﯾﺸﯽ ﻧﺘﺎﯾﺞ در ﻗﺎﻟـﺐ ﻃـﺮح آﻟﻔﺎ ﻻﺗﯿﺲ ﺑﺎ دو ﺗﮑﺮار در دو ﺗﺎرﯾﺦ ﮐﺸﺖ ﻧﯿﻤﻪ اول ﻣﻬﺮ )ﻧﺮﻣﺎل( و ﻧﯿﻤﻪ اول آﺑﺎن )ﺗﺄﺧﯿﺮي( ﻃﯽ دو ﺳﺎل در ﮐﺮج اﺟﺮا ﺷـﺪ. ﻧﺘـﺎﯾﺞ ﺗﺠﺰﯾـﻪ وارﯾﺎﻧﺲ ﻣﺮﮐﺐ ﻧﺸﺎن داد ﻋﻤﻠﮑﺮد داﻧﻪ ژﻧﻮﺗﯿﭗﻫﺎ در ﺳﻄﺢ اﺣﺘﻤﺎل ﯾﮏ درﺻﺪ ﺑﺎ ﯾﮑﺪﯾﮕﺮ اﺧﺘﻼف دارﻧﺪ و ﺗﻨﻮع ژﻧﺘﯿﮑﯽ ﻗﺎﺑـﻞ ﺗـﻮﺟﻬ ﯽ ﺑـ ﯿﻦ ژﻧﻮﺗﯿﭗﻫﺎي ﻣﻮرد ﺑﺮرﺳﯽ وﺟﻮد دارد. ﻫﻤﭽﻨﯿﻦ ﺑﯿﻦ ﻣﺤﯿﻂﻫﺎ )ﮐﺸﺖ ﻣﻌﻤﻮل و ﺗﺄﺧﯿﺮي( در ﻫﺮ دو ﺳﺎل آزﻣﺎﯾﺶ ﺗﻔـﺎوت ﻣﻌﻨـﯽ دار در ﺳـﻄﺢ اﺣﺘﻤﺎل ﯾﮏ درﺻﺪ وﺟﻮد داﺷﺖ. ﻧﺘﺎﯾﺞ ﻧﺸﺎن داد ﺗﺄﺧﯿﺮ در ﮐﺎﺷﺖ ﺑﺎﻋﺚ ﮐﺎﻫﺶ ﻋﻤﻠﮑﺮد داﻧﻪ ﮐﻠﺰا از 4/09 ﺗﻦ در ﻫﮑﺘﺎر )در ﺷﺮاﯾﻂ ﮐﺸـﺖ ﻣﻌﻤﻮل و ﺑﺪون ﺗﻨﺶ ﺳﺮﻣﺎ( ﺑﻪ2/72 ﺗﻦ در ﻫﮑﺘﺎر )در ﺷﺮاﯾﻂ ﮐﺸﺖ ﺗﺄﺧﯿﺮي وﺗﻨﺶ ﺳﺮﻣﺎ( ﺷﺪه اﺳﺖ. ﺗﺠﺰﯾﻪ ﺑﻪ ﻣﺆﻟﻔﻪﻫﺎي اﺻﻠﯽ ﺑﺎ اﺳﺘﻔﺎده از ﺷﺶ ﺷﺎﺧﺺ ﺗﺤﻤﻞ ﺑﻪ ﺗﻨﺶ ﺳﺮﻣﺎ )SSI ،TOL ،HARM ،GMP ،MP و STI( ﻧﺸﺎن داد دو ﻣﺆﻟﻔـﻪ اول در ﺣـﺪود 99/85 درﺻـﺪ از ﺗﻨـﻮع ﻣﻮﺟﻮد در ﺟﻤﻌﯿﺖ را ﺗﻮﺟﯿﻪ ﻣﯽﮐﻨﺪ. ﺑﺎيﭘﻼت ﻣﺆﻟﻔﻪ اول روي ﻣﺆﻟﻔﻪ دوم ژﻧﻮﺗﯿﭗﻫﺎ را ﺑﻪ ﭼﻬﺎر ﮔﺮوه ﻣﺨﺘﻠـﻒ ﺗﻘﺴـ ﯿﻢ ﮐـﺮد و 29 ژﻧﻮﺗﯿـ ﭗ ﭘﺮﻣﺤﺼﻮل و ﻣﺘﺤﻤﻞ ﺑﻪ ﺳﺮﻣﺎ را ﺷﻨﺎﺳﺎﯾﯽ ﮐﺮد. ﺗﺠﺰﯾﻪ ﮐﻼﺳﺘﺮ ژﻧﻮﺗﯿﭗﻫﺎ را ﺑﻪ ﭼﻬﺎر ﮔﺮوه ﻣﺨﺘﻠﻒ ﺗﻘﺴﯿﻢ ﮐﺮد و ﮔـﺮوه ﺑﻨـﺪ ي ژﻧﻮﺗﯿـ ﭗﻫـﺎ ﺑـﺎ اﺳﺘﻔﺎده از ﺗﺠﺰﯾﻪ ﮐﻼﺳﺘﺮ ﻣﻄﺎﺑﻘﺖ ﺧﻮﺑﯽ ﺑﺎ ﻧﺘﺎﯾﺞ ﺗﺠﺰﯾﻪ ﺑﻪ ﻣﺆﻟﻔﻪﻫﺎي اﺻﻠﯽ ﻧﺸﺎن داد. ﻧﺘﺎﯾﺞ ﻫﻤﺒﺴﺘﮕﯽ ﺑﯿﻦ ﺷﺎﺧﺺﻫﺎي ﻣﺨﺘﻠﻒ ﺗﺤﻤﻞ ﺑﻪ ﺗﻨﺶ ﺑﺎ ﻋﻤﻠﮑﺮد در ﺷﺮاﯾﻂ ﺗﻨﺶ )YP( و ﺑﺪون ﺗﻨﺶ )YS( ﻧﺸﺎن داد دو ﺷﺎﺧﺺ TOL و SSI ﺑـﺎ YP )ﻋﻤﻠﮑـﺮد در ﺷـﺮ اﯾﻂ ﺑـﺪون ﺗـﻨ ﺶ( داراي ﻫﻤﺒﺴﺘﮕﯽ ﻣﺜﺒﺖ و ﺑﺎ YS )ﻋﻤﻠﮑﺮد در ﺷﺮاﯾﻂ ﺗﻨﺶ( داراي ﻫﻤﺒﺴﺘﮕﯽ ﻣﻨﻔﯽ ﻫﺴﺘﻨﺪ. ﻋﻼوه ﺑﺮ اﯾﻦ ﭼﻬﺎر ﺷﺎﺧﺺ HARM ،GMP ،MP و STI داراي ﻫﻤﺒﺴﺘﮕﯽ ﻣﺜﺒﺖ و ﻣﻌﻨﯽدار ﺑﺎ ﻋﻤﻠﮑﺮد در ﻫﺮدو ﺷﺮاﯾﻂ ﺗﻨﺶ و ﺑﺪون ﺗﻨﺶ ﺑﻮدﻧﺪ. ﻧﺘﺎﯾﺞ اﯾﻦ ﭘﮋوﻫﺶ ﻧﺸﺎن داد ﺷﺎﺧﺺSTI از ﮐﺎراﻣﺪي ﺑﺎﻻﯾﯽ ﺑﻪﻣﻨﻈﻮر ﮔﺰﯾﻨﺶ ژﻧﻮﺗﯿﭗﻫﺎي ﮐﻠﺰا ﺑﺮاي ﺗﺤﻤﻞ ﺳﺮﻣﺎ ﺑﺮﺧﻮردار ﺑﻮده اﺳﺖ و ﺑﻪﻃﻮر ﻣﻮﻓﻘﯿﺖآﻣﯿﺰي ﻣﯽﺗﻮاﻧﺪ در ﺑﺮﻧﺎﻣـﻪ ﻫـﺎ ي اﺻـﻼﺣ ﯽ ﺑﻪﮐﺎر ﮔﺮﻓﺘﻪ ﺷﻮد.

In order to study the response of 120 genotypes of rapeseed (including 100 hybrids and 20 parents) in terms of cold stress tolerance, an experiment was conducted in α-lattice design with two replications under normal (September) and late sowing (October) conditions during two years. Combined analysis of variance showed that genotypes were significantly different at 1% and there was a significant genetic variation among the studied genotypes. In addition, there was a significant difference between the environments (normal and late sowing) at 1% in both years and the effect of late sowing on the yield of rapeseed was different from that of normal sowing. Total mean of seed yield in nonstressed condition was 4.9 ton/ha and in cold stress condition was 2.72 t/ha (34% reduction compared to normal sowing conditions). Principal component analysis (PCA) using six indices of cold stress tolerance (MP, GMP, HARM, TOL, SSI and STI) showed that the first two components justify about 99.85% of the variation in the population. The biplot of first and second components divided the genotypes into four different groups and identified 29 high yielding and cold tolerant genotypes. Similarly, cluster analysis divided the genotypes into four different groups and grouping of genotypes using cluster analysis showed good agreement with the results of principal component analysis. Correlation between different indices of stress tolerance and yield in stress (YP) and non- stress (YS) condition showed that TOL and SSI had positive correlation with YP and negative correlation with YS. Furthermore, the four indices of MP, GMP, HARM and STI showed positive and significant correlation with yield in both stressed and non-stress conditions. The results of this study showed that the STI index has a high efficiency in selection of rapeseed genotypes for cold tolerance and can be successfully applied in breeding programs.