ارزیابی تنوع ژنتیکی جمعیت‌های گز پرشاخه (tamarix ramosissima ledeb.) در استان اصفهان با استفاده از نشانگر مولکولی cddp

گونه‌های گز (tamarix) دربرابر شرایط نامساعد محیطی بردبارند و پراکنش شایان توجهی در مناطق خشک و شور دارند. گز پرشاخه بیشترین پراکنش را در بین گونه‌های گز موجود در استان اصفهان دارد و بیشتر در عرصه‌های خشک و بیابانی مستقر است. به‌‌دلیل وجود تنوع ریخت‌‌شناسی زیاد این گونه و افتراق‌‌نیافتن جمعیت‌‌ها و به‌‌منظور بررسی تنوع موجود در جمعیت‌های این گونه، تعداد 55 جمعیت از 15 شهرستان استان اصفهان شناسایی و از هر جمعیت یک فرد نمونه‌برداری شد. پس از استخراج ژنوم آنها، از 10 آغازگر نشانگر cddp برای بررسی تنوع ژنتیکی جمعیت‌های این گیاه استفاده شد. برای تجزیه و تحلیل داده‌ها، نرم‌‌افزارهای ntsys-pc، genalex و powermarker به کار گرفته شد. نتایج بیانگر تولید 124 باند بود؛ به طوری که از این تعداد، 102 باند (80.168 درصد) به‌‌صورت چندشکلی (پلی‌‌مورف) بود. به‌‌طور متوسط هر آغازگر 7.85 درصد، باند چندشکلی ایجاد کرد. آغازگر wrky-f1 با تولید 16 باند، مکان‌‌های ژنی بیشتری را نسبت به سایر آغازگرها شناسایی کرد. میانگین محتوای اطلاعات چندشکلی (pic) به میزان 0.308 محاسبه شد. شاخص نشانگر برای هر آغازگر به‌‌طور میانگین 3.865 بود. آنالیز واریانس مولکولی نشان داد تنوع درون‌‌جمعیتی از تنوع بین جمعیتی بیشتر بود. آنالیز خوشه‌‌ای و pcoa حاکی از وجود دو جمعیت مجزا و سه زیرجمعیت در بین آنها بود. درمجموع، موثربودن نشانگر cddp در تفکیک جمعیت‌های گز پرشاخه و زیادبودن تنوع ژنتیکی درون جمعیت‌‌ها تایید شد که صفتی ارزشمند برای اهداف اصلاحی است.

genetic diversity assessment of saltcedar (tamarix ramosissima ledeb.) populations in isfahan province using cddp molecular marker

tamarix species are tolerant to adverse environmental conditions and have significant distribution in dry and salty areas. tamarix ramosissima is the most widely distributed species among tamarix in isfahan province and is mostly located in dry and desert areas. due to the high morphological diversity of this species and the lack of population differentiation and in order to investigate the diversity in the populations of this species, 55 populations from 15 cities of isfahan province were identified and one individual was sampled from each population. after extracting their genome, 10 cddp marker primers were used to investigate the genetic diversity of the populations of this plant. ntsys-pc, genalex and powermarker software were used for data analysis. the results showed 102 bands (80.168%) were polymorphic among the production of 124 bands. on average, each primer created an 7.85%  polymorphic band. wrky-f1 primer identified more gene locations than other primers by producing 16 bands. the average polymorphic information content (pic) was calculated as 0.308. the indicator index for each primer was 3.865 on average. molecular analysis of variance showed that intra-population variation was higher than inter-population variation. cluster analysis and pcoa indicated the existence of two separate populations and three subpopulations among them. in general, the effectiveness of the cddp marker in differentiating the populations of tamarix ramosissima and the high genetic diversity within the populations, which is a valuable trait for breeding purposes, were confirmed.introductionthe genus tamarix, which is included in tamaricaceae, is one of the most difficult taxonomically related tree genera. it is not possible to separate and differentiate the species of the genus using vegetative traits. in addition, hybridization between the species of the genus, followed by introgression, is one of the reasons that has made the classification of this genus difficult. tamarix species are tolerant to adverse environmental conditions and have significant distribution in dry and salty areas. t. ramosissima has the most distribution among the species of the genus in isfahan province and is mostly located in dry and desert areas. the high morphological diversity of this species and the lack of differentiation of populations have doubled the necessity of careful study of populations. the genetic diversity of t. ramosissima has not been studied in iran. also, there is very little detailed information about the taxonomy, genetic structure, and population genetics of the species that grow in iran. therefore, in this research, using the cddp molecular marker, the populations of this species have been investigated in isfahan province. materials and methodsin order to investigate the diversity in the populations of this species, 55 populations from 15 cities of isfahan province were identified and one individual was sampled from each population. after extracting their genome, 10 cddp marker primers were used to investigate the genetic diversity of this plant population. ntsys-pc, genalex, and powermarker software were used for data analysis. genomic dna was extracted from plant leaves. the quantity and quality of the extracted dnas were evaluated using a spectrophotometer at 260 nm wavelength and 0.8% agarose gel. the initial annealing step for isolation and single-stranded dna of the template was 4 minutes at 94°c temperature, and then 35 cycles including the annealing step were performed at 94 °c temperature for 1 minute. pcr reaction products were identified using electrophoresis on 1.5% agarose gel with a geldak machine. research findingsthe results showed that by using 10 primers, a total of 124 bands were produced, of which 102 bands (80.168%) were polymorphic. the wrky-f1 primer produced 16 bands and identified more gene locations than other primers, and the wrky-r3 primer produced the lowest number of bands by producing 8 bands. the lowest and highest amount of polymorphism were related to primers wrky-r3, mads-4 with 5 bands (62.50%, 45.45%), and abp1-1 with 15 bands (100%), respectively. on average, each primer created an 85.7% polymorphic band. the average polymorphic information content (pic) was calculated as 0.308, the highest value of which was related to the mads-2 primer with a value of 0.455, and the lowest value was related to the knox-2 primer with a value of 0.0975. the average marker index for each primer was 3.865, and the highest and lowest values were related to abp1-1 (6.664) and knox-2 (1.56), respectively. molecular analysis of variance showed that intra-population variation was higher than inter-population variation. cluster analysis and pcoa indicated the existence of two separate populations and three subpopulations among them. the results of mantel’s test data showed the amount of genetic difference, genetic distance, and geographic distance between the populations of saltcedar, so there was no significant relationship between genetic distance and geographic distance at the level of 5%. discussion of results and conclusionin the present study, very high genetic diversity was observed within the populations of each location. considering the ecological conditions prevailing in the isfahan region, this amount of diversity is not far from expected. in fact, unfavorable environmental conditions and geographical isolation are factors that individuals of species tend to accumulate genetic changes during the period of adaptation to the environment. the effectiveness of the cddp marker in differentiating the populations of t. ramosissima and the high genetic diversity within the populations, which is a valuable trait for breeding purposes, were confirmed. in addition, examining the similarity of the populations by drawing the dendrogram and the pcoa coordinate axis showed that the studied populations are divided into two main groups and three subpopulations. genotypes that occurred in isfahan showed the highest genetic diversity among the populations.