The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions ... more The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions representing six Egyptian cultivars were assayed using 27 RAPD and 10 ISSR primers. The level of polymorphism among the 14 accessions as revealed by RAPD and ISSR was 25.2% and 28.6%, respectively. These low levels of polymorphism reflect the narrow genetic background of these accessions. The genetic relationships among the 14 accessions were estimated in terms of similarity using Dice coefficients. The genetic similarity ranged from 96.1% to 99.5% and from 91.2% to 100% for RAPD and ISSR, respectively. The inter-cultivar relationships among the six date palm cultivars based on RAPD and ISSR revealed the highest genetic similarity between the cultivar Bertmoda and each of the cultivars Malkaby and Sakkoty. The RAPD and ISSR based dendrograms clustered the accessions belonging to each of the 3 cultivars Fraihy, Siwi and Gandila in separate groups. However, the reshuffling in the position ...
Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egyp... more Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egypt representing six Egyptian cultivars: Sakkoty, Bertmoda, Malkaby, Gandila, Fraihy and Siwi were assayed using 16 AFLP primer combinations. AFLP analysis generated a total of 657 amplicons representing a level of polymorphism of 45.8%. The genetic similarity and relationships were estimated among the 14 accessions and among the six cultivars according to Dice coefficient.The AFLP-based dendrograms clustered the genotypes of some cultivars together, i.e. Fraihy and Gandila. The genotypes of Siwi cultivar were clustered together also, but they exhibited some degree of intravarietal variation. The other three cultivars (Sakkoty, Bertmoda, and Malkaby) showed higher degree of intravarietal variation. Moreover, at the intervarietal level, the AFLP assay separated the oases cultivars i.e., Siwi and Fraihy, from the cultivars from Aswan, i.e. Sakkoty, Bertmoda, Malkaby and Gandila. AFLP analysi...
Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards... more Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards worldwide. Survey of grapvine farms in Taif governorate, Mecca province, Kingdom of Saudi Arabia resulted in the detection of Grapevine plants (Vitis vinifera cv. Perelette) exhibited virus-like symptoms of the GFLV. Symptomatic samples were collected to confirm the viral infection through Double antibody sandwich-enzyme linked immunosorbent (DAS-ELISA) assay with Polyclonal antibodies (PAbs) specific to GFLV. Out of 48 tested samples, 43 samples representing 89.6% gave positive reactions with values ranged between 0.116 and 2,462 compared to values ranged between 0.003 and 0.085 of the 5 negative healthy samples. Grapevine plant with high viral titer showed typical fanleaf symptoms such as abnormal branching, double nodes, short Internodes with zigzag growth and fasciations, reduction of the leaves size with deformities and fan-leaf shape. These results were biologically confirmed following the detection of leaves malformation symptoms, mottling, ringspots and systemic chlorotic mosaic, in viral infected Nicotiana benthamiana, Phaseolus vulgaris and Cucurbita pepo, respectively. The inoculated plants developed symptoms 21 days post inoculation. The result obtained by ELISA was confirmed by western blot assay. To our knowledge, this is the first study performed in KSA dealing with the detection of grapevine viruses in naturally infected field-grown vines.
Traditional biotechnology is defined as using organisms to make products, improve plants, animals... more Traditional biotechnology is defined as using organisms to make products, improve plants, animals or microbes in purpose of using them in agriculture, industry, medical purposes and environment protection through traditional methods, e.g. hybridization, mutants or fermentation. While, modern biotechnology is basically the same, but through employing modern genetic engineering techniques, e.g. recombinant DNA, monoclonal antibodies or cell and tissue culture. It is clearly indicated that there is a global increase of the cultivated area of genetically modified crops (e.g. soybeans, corn, tomatoes, canola and sugar beet) from 1996 to 2014. Moreover, industrial crops such as cotton combat the adverse environmental conditions and solve the problems of desertification, drought and food production, medicine and afforestation of desert land. In conclusion, we see an excellent possibility of employing biotechnology applications for solving environmental and agricultural problems of Saudi Arabia, especially water, feed and food shortages. It is worthwhile for the Saudi government to include biotechnology applications in the Saudi “2030 Vision” and to subsidize biotechnology research and applications in order to overcome the drought and salt tolerance barriers, especially for the mainstays of food and feed in the kingdom such as Date Palm, Barley, Millet and Alfalfa. Besides the potential of investment in biofuels research and production, there is a good niche for the conservation and utilization of the available genetic resources in Saudi Arabia. Hence, there is an urgent need for Saudi Arabia to establish a legal foundation in agricultural biotechnology for future applications in order to encourage the research and investment in biotechnology and to increase the public awareness and acceptance.
Fibrillins are large family of proteins that form a major constituent of microfibrils and subsequ... more Fibrillins are large family of proteins that form a major constituent of microfibrils and subsequently the extracellular matrix. Fibrillin-1 is the most characterized fibrillin member and has been verified to be linked to Marfan syndrome. Fibrillin-2 was linked to congenital contractural arachnodactyly. Fibrillin-3 is expressed during tissues development and it has been linked to Weill Marchesani syndrome and polycystic ovary syndrome. Self-assembly and multiple ligand binding properties of fibrillins are crucial for the proper formation and function of microfibrils. These properties are often compromised in pathological situations. Therefore, we aimed to study the interaction epitopes of the N-terminal of fibrillin-3 with fibulin-2 and heparin in comparison to fibrillin-1, as well as the molecular shapes of the N-terminal region of fibrillin-3. In the present study we compared the binding of fibulin-2 and heparin to the N-terminal polypeptides of both fibrilin-1 and fibrillin-3. Also, we compared folding shapes of their N-termini. Our results indicated the similarity of N-termini of both fibrillin-1 and fibrillin-3 in binding to fibulin-2 and heparin as well as their structures. The N-terminal polypeptides of Fibrillin-3 can interact with Fibulin-2 and heparin in a similar fashion as compared to fibrillin-1, indicating similar functions for both isoforms.
Genomics–based approaches offer unprecedented opportunities for crop improvement. Mapping of the ... more Genomics–based approaches offer unprecedented opportunities for crop improvement. Mapping of the chromosomal regions affecting qualitative and/or quantitative traits using molecular markers is receiving a growing attention in the last few decades. We used 50 EST, 18 EST-SSR, 36 SSR primers and 64 AFLP primer combinations to develop a molecular linkage map of cotton employing F2 segregating population obtained through an interspecific cross between Giza 45 (G. barbadense) and Tamcot Luxor (G. hirsutum). Analysis of segregation among the resulting 60 F2 individuals was performed using 1 EST, 4 EST-SSR, 14 SSR primers and 10 AFLP primer combinations that revealed consistent polymorphic patterns and were employed for constructing a genetic linkage map that included 210 molecular markers located on 26 linkage groups and spanning a total length of 3503.8 cM. We detected 81 significant QTLs related to earliness, high yield, and fiber quality, which is promising for a better understanding of the cotton crop. Our map is covering ~75.2% of the total recombinational length of the cotton genome with an average marker interval of 16.7cM. SSR markers were used to assign the linkage groups to specific chromosomes. Seven linkage groups were assigned to chromosomes. This map represents the first map for the intercross between Giza 45 and Tamcot Luxor and could be considered as a framework map to overcome the limitations of conventional breeding for the improvement of cotton yield, earliness and fiber quality related traits.
Congenital Chloride Diarrhea (CLD) is a watery diarrhea with metabolic alkalosis and excess chlor... more Congenital Chloride Diarrhea (CLD) is a watery diarrhea with metabolic alkalosis and excess chloride in feces. It is an autosomal recessive inherited disease caused by mutations in SLC26A3 gene with higher incidence in Arab countries. Due to Arab consanguineous marriages, only one founder mutation (Gly187Ter)was reported in exon5.We sequenced exon5 to study the molecular background in 27 CLD children from Taif, Saudi Arabia. Interestingly, the mutation (NG_008046.1:g.17175G>T, ss904491498) was consistent in all children. These results will support developing CLD early detection kits and specific treatments. Adding it to the Saudi pre-marital check-up program would greatly decrease CLD burden. We are looking forward to include screening for the reported founder mutation in the Saudi pre-marital checkup program hoping to decrease the burden of this inherited lifelong disease and with the challenge of developing specific treatment.
The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions ... more The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions representing six Egyptian cultivars were assayed using 27 RAPD and 10 ISSR primers. The level of polymorphism among the 14 accessions as revealed by RAPD and ISSR was 25.2% and 28.6%, respectively. These low levels of polymorphism reflect the narrow genetic background of these accessions. The genetic relationships among the 14 accessions were estimated in terms of similarity using Dice coefficients. The genetic similarity ranged from 96.1% to 99.5% and from 91.2% to 100% for RAPD and ISSR, respectively. The inter-cultivar relationships among the six date palm cultivars based on RAPD and ISSR revealed the highest genetic similarity between the cultivar Bertmoda and each of the cultivars Malkaby and Sakkoty. The RAPD and ISSR based dendrograms clustered the accessions belonging to each of the 3 cultivars Fraihy, Siwi and Gandila in separate groups. However, the reshuffling in the position of some of the accessions belonging to the other cultivars in the different dendrograms revealed that they share common gnenetic background. Cultivar-specific DNA markers characterized different genotypes and therefore, were used to generate unique fingerprint for each genotype. The RAPD and ISSR revealed 17 and 5 cultivar unique DNA markers, characterizing 4 and 5 cultivars, respectively. Moreover, each of the RAPD and ISSR was successful in identifying accession-specific markers characterizing five accessions.
Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egyp... more Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egypt representing six Egyptian cultivars: Sakkoty, Bertmoda, Malkaby, Gandila, Fraihy and Siwi were assayed using 16 AFLP primer combinations. AFLP analysis generated a total of 657 amplicons representing a level of polymorphism of 45.8%. The genetic similarity and relationships were estimated among the 14 accessions and among the six cultivars according to Dice coefficient.The AFLP-based dendrograms clustered the genotypes of some cultivars together, i.e. Fraihy and Gandila. The genotypes of Siwi cultivar were clustered together also, but they exhibited some degree of intravarietal variation. The other three cultivars (Sakkoty, Bertmoda, and Malkaby) showed higher degree of intravarietal variation. Moreover, at the intervarietal level, the AFLP assay separated the oases cultivars i.e., Siwi and Fraihy, from the cultivars from Aswan, i.e. Sakkoty, Bertmoda, Malkaby and Gandila. AFLP analysis permitted the characterization of each cultivar by specific unique markers.Data from RAPD's and ISSR's, previously obtained on the same 14 accessions were combined with AFLP's to generate more accurate relationships based on large and versatile genome coverage. The dendrogram based on the combined data from the different types of markers (RAPD, ISSR and AFLP) was closest to the AFLP-based dendrogram. To evaluate the efficiency of the different marker systems, the sum effective number of alleles (SENA), the average expected heterozygosity for polymorphic markers (Hav(p)), the effective multiplex ratio (E) and marker index (MI) were calculated. The AFLP exhibited considerably high sum effective number of alleles (205.7) compared to RAPD and ISSR (45.1 and 17.8, respectively). The average heterozygosity was also higher in AFLP (0.39) than in RAPD and ISSR (0.36 and 0.35, respectively). The MI was 117.3 in AFLP while it was 95.9 and 10.4 in RAPD and ISSR, respectively. Thus, the results indicated that AFLP is more effective in detecting high level of polymorphism. The correlation coefficient was considerably high between RAPD and ISSR (0.68), and it was lower between RAPD and AFLP (0.23) than that between AFLP and ISSR (0.34). The results confirmed that different marker systems differ in the mechanism of detecting polymorphism, genome coverage and the ease of application. Therefore, they could complement each other to draw more accurate conclusions.
Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards... more Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards worldwide. Survey of grapvine farms in Taif governorate, Mecca province, Kingdom of Saudi Arabia resulted in the detection of Grapevine plants (Vitis vinifera cv. Perelette) exhibited virus-like symptoms of the GFLV. Symptomatic samples were collected to confirm the viral infection through Double antibody sandwich-enzyme linked immunosorbent (DAS-ELISA) assay with Polyclonal antibodies (PAbs) specific to GFLV. Out of 48 tested samples, 43 samples representing 89.6% gave positive reactions with values ranged between 0.116 and 2,462 compared to values ranged between 0.003 and 0.085 of the 5 negative healthy samples. Grapevine plant with high viral titer showed typical fanleaf symptoms such as abnormal branching, double nodes, short Internodes with zigzag growth and fasciations, reduction of the leaves size with deformities and fan-leaf shape. These results were biologically confirmed following the detection of leaves malformation symptoms, mottling, ringspots and systemic chlorotic mosaic, in viral infected Nicotiana benthamiana, Phaseolus vulgaris and Cucurbita pepo, respectively. The inoculated plants developed symptoms 21 days post inoculation. The result obtained by ELISA was confirmed by western blot assay. To our knowledge, this is the first study performed in KSA dealing with the detection of grapevine viruses in naturally infected field-grown vines. Lanes 2-4 are plant viral preparation, lane 1-3 is negative control (healthy plant), (Mr) broad range Farmntas protein marker.
The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions ... more The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions representing six Egyptian cultivars were assayed using 27 RAPD and 10 ISSR primers. The level of polymorphism among the 14 accessions as revealed by RAPD and ISSR was 25.2% and 28.6%, respectively. These low levels of polymorphism reflect the narrow genetic background of these accessions. The genetic relationships among the 14 accessions were estimated in terms of similarity using Dice coefficients. The genetic similarity ranged from 96.1% to 99.5% and from 91.2% to 100% for RAPD and ISSR, respectively. The inter-cultivar relationships among the six date palm cultivars based on RAPD and ISSR revealed the highest genetic similarity between the cultivar Bertmoda and each of the cultivars Malkaby and Sakkoty. The RAPD and ISSR based dendrograms clustered the accessions belonging to each of the 3 cultivars Fraihy, Siwi and Gandila in separate groups. However, the reshuffling in the position ...
Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egyp... more Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egypt representing six Egyptian cultivars: Sakkoty, Bertmoda, Malkaby, Gandila, Fraihy and Siwi were assayed using 16 AFLP primer combinations. AFLP analysis generated a total of 657 amplicons representing a level of polymorphism of 45.8%. The genetic similarity and relationships were estimated among the 14 accessions and among the six cultivars according to Dice coefficient.The AFLP-based dendrograms clustered the genotypes of some cultivars together, i.e. Fraihy and Gandila. The genotypes of Siwi cultivar were clustered together also, but they exhibited some degree of intravarietal variation. The other three cultivars (Sakkoty, Bertmoda, and Malkaby) showed higher degree of intravarietal variation. Moreover, at the intervarietal level, the AFLP assay separated the oases cultivars i.e., Siwi and Fraihy, from the cultivars from Aswan, i.e. Sakkoty, Bertmoda, Malkaby and Gandila. AFLP analysi...
Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards... more Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards worldwide. Survey of grapvine farms in Taif governorate, Mecca province, Kingdom of Saudi Arabia resulted in the detection of Grapevine plants (Vitis vinifera cv. Perelette) exhibited virus-like symptoms of the GFLV. Symptomatic samples were collected to confirm the viral infection through Double antibody sandwich-enzyme linked immunosorbent (DAS-ELISA) assay with Polyclonal antibodies (PAbs) specific to GFLV. Out of 48 tested samples, 43 samples representing 89.6% gave positive reactions with values ranged between 0.116 and 2,462 compared to values ranged between 0.003 and 0.085 of the 5 negative healthy samples. Grapevine plant with high viral titer showed typical fanleaf symptoms such as abnormal branching, double nodes, short Internodes with zigzag growth and fasciations, reduction of the leaves size with deformities and fan-leaf shape. These results were biologically confirmed following the detection of leaves malformation symptoms, mottling, ringspots and systemic chlorotic mosaic, in viral infected Nicotiana benthamiana, Phaseolus vulgaris and Cucurbita pepo, respectively. The inoculated plants developed symptoms 21 days post inoculation. The result obtained by ELISA was confirmed by western blot assay. To our knowledge, this is the first study performed in KSA dealing with the detection of grapevine viruses in naturally infected field-grown vines.
Traditional biotechnology is defined as using organisms to make products, improve plants, animals... more Traditional biotechnology is defined as using organisms to make products, improve plants, animals or microbes in purpose of using them in agriculture, industry, medical purposes and environment protection through traditional methods, e.g. hybridization, mutants or fermentation. While, modern biotechnology is basically the same, but through employing modern genetic engineering techniques, e.g. recombinant DNA, monoclonal antibodies or cell and tissue culture. It is clearly indicated that there is a global increase of the cultivated area of genetically modified crops (e.g. soybeans, corn, tomatoes, canola and sugar beet) from 1996 to 2014. Moreover, industrial crops such as cotton combat the adverse environmental conditions and solve the problems of desertification, drought and food production, medicine and afforestation of desert land. In conclusion, we see an excellent possibility of employing biotechnology applications for solving environmental and agricultural problems of Saudi Arabia, especially water, feed and food shortages. It is worthwhile for the Saudi government to include biotechnology applications in the Saudi “2030 Vision” and to subsidize biotechnology research and applications in order to overcome the drought and salt tolerance barriers, especially for the mainstays of food and feed in the kingdom such as Date Palm, Barley, Millet and Alfalfa. Besides the potential of investment in biofuels research and production, there is a good niche for the conservation and utilization of the available genetic resources in Saudi Arabia. Hence, there is an urgent need for Saudi Arabia to establish a legal foundation in agricultural biotechnology for future applications in order to encourage the research and investment in biotechnology and to increase the public awareness and acceptance.
Fibrillins are large family of proteins that form a major constituent of microfibrils and subsequ... more Fibrillins are large family of proteins that form a major constituent of microfibrils and subsequently the extracellular matrix. Fibrillin-1 is the most characterized fibrillin member and has been verified to be linked to Marfan syndrome. Fibrillin-2 was linked to congenital contractural arachnodactyly. Fibrillin-3 is expressed during tissues development and it has been linked to Weill Marchesani syndrome and polycystic ovary syndrome. Self-assembly and multiple ligand binding properties of fibrillins are crucial for the proper formation and function of microfibrils. These properties are often compromised in pathological situations. Therefore, we aimed to study the interaction epitopes of the N-terminal of fibrillin-3 with fibulin-2 and heparin in comparison to fibrillin-1, as well as the molecular shapes of the N-terminal region of fibrillin-3. In the present study we compared the binding of fibulin-2 and heparin to the N-terminal polypeptides of both fibrilin-1 and fibrillin-3. Also, we compared folding shapes of their N-termini. Our results indicated the similarity of N-termini of both fibrillin-1 and fibrillin-3 in binding to fibulin-2 and heparin as well as their structures. The N-terminal polypeptides of Fibrillin-3 can interact with Fibulin-2 and heparin in a similar fashion as compared to fibrillin-1, indicating similar functions for both isoforms.
Genomics–based approaches offer unprecedented opportunities for crop improvement. Mapping of the ... more Genomics–based approaches offer unprecedented opportunities for crop improvement. Mapping of the chromosomal regions affecting qualitative and/or quantitative traits using molecular markers is receiving a growing attention in the last few decades. We used 50 EST, 18 EST-SSR, 36 SSR primers and 64 AFLP primer combinations to develop a molecular linkage map of cotton employing F2 segregating population obtained through an interspecific cross between Giza 45 (G. barbadense) and Tamcot Luxor (G. hirsutum). Analysis of segregation among the resulting 60 F2 individuals was performed using 1 EST, 4 EST-SSR, 14 SSR primers and 10 AFLP primer combinations that revealed consistent polymorphic patterns and were employed for constructing a genetic linkage map that included 210 molecular markers located on 26 linkage groups and spanning a total length of 3503.8 cM. We detected 81 significant QTLs related to earliness, high yield, and fiber quality, which is promising for a better understanding of the cotton crop. Our map is covering ~75.2% of the total recombinational length of the cotton genome with an average marker interval of 16.7cM. SSR markers were used to assign the linkage groups to specific chromosomes. Seven linkage groups were assigned to chromosomes. This map represents the first map for the intercross between Giza 45 and Tamcot Luxor and could be considered as a framework map to overcome the limitations of conventional breeding for the improvement of cotton yield, earliness and fiber quality related traits.
Congenital Chloride Diarrhea (CLD) is a watery diarrhea with metabolic alkalosis and excess chlor... more Congenital Chloride Diarrhea (CLD) is a watery diarrhea with metabolic alkalosis and excess chloride in feces. It is an autosomal recessive inherited disease caused by mutations in SLC26A3 gene with higher incidence in Arab countries. Due to Arab consanguineous marriages, only one founder mutation (Gly187Ter)was reported in exon5.We sequenced exon5 to study the molecular background in 27 CLD children from Taif, Saudi Arabia. Interestingly, the mutation (NG_008046.1:g.17175G>T, ss904491498) was consistent in all children. These results will support developing CLD early detection kits and specific treatments. Adding it to the Saudi pre-marital check-up program would greatly decrease CLD burden. We are looking forward to include screening for the reported founder mutation in the Saudi pre-marital checkup program hoping to decrease the burden of this inherited lifelong disease and with the challenge of developing specific treatment.
The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions ... more The genetic variability and relationships among 14 date palm (Phoenix dactylifera L.) accessions representing six Egyptian cultivars were assayed using 27 RAPD and 10 ISSR primers. The level of polymorphism among the 14 accessions as revealed by RAPD and ISSR was 25.2% and 28.6%, respectively. These low levels of polymorphism reflect the narrow genetic background of these accessions. The genetic relationships among the 14 accessions were estimated in terms of similarity using Dice coefficients. The genetic similarity ranged from 96.1% to 99.5% and from 91.2% to 100% for RAPD and ISSR, respectively. The inter-cultivar relationships among the six date palm cultivars based on RAPD and ISSR revealed the highest genetic similarity between the cultivar Bertmoda and each of the cultivars Malkaby and Sakkoty. The RAPD and ISSR based dendrograms clustered the accessions belonging to each of the 3 cultivars Fraihy, Siwi and Gandila in separate groups. However, the reshuffling in the position of some of the accessions belonging to the other cultivars in the different dendrograms revealed that they share common gnenetic background. Cultivar-specific DNA markers characterized different genotypes and therefore, were used to generate unique fingerprint for each genotype. The RAPD and ISSR revealed 17 and 5 cultivar unique DNA markers, characterizing 4 and 5 cultivars, respectively. Moreover, each of the RAPD and ISSR was successful in identifying accession-specific markers characterizing five accessions.
Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egyp... more Fourteen date palm (Phoenix dactylifera L.) accessions collected from different locations in Egypt representing six Egyptian cultivars: Sakkoty, Bertmoda, Malkaby, Gandila, Fraihy and Siwi were assayed using 16 AFLP primer combinations. AFLP analysis generated a total of 657 amplicons representing a level of polymorphism of 45.8%. The genetic similarity and relationships were estimated among the 14 accessions and among the six cultivars according to Dice coefficient.The AFLP-based dendrograms clustered the genotypes of some cultivars together, i.e. Fraihy and Gandila. The genotypes of Siwi cultivar were clustered together also, but they exhibited some degree of intravarietal variation. The other three cultivars (Sakkoty, Bertmoda, and Malkaby) showed higher degree of intravarietal variation. Moreover, at the intervarietal level, the AFLP assay separated the oases cultivars i.e., Siwi and Fraihy, from the cultivars from Aswan, i.e. Sakkoty, Bertmoda, Malkaby and Gandila. AFLP analysis permitted the characterization of each cultivar by specific unique markers.Data from RAPD's and ISSR's, previously obtained on the same 14 accessions were combined with AFLP's to generate more accurate relationships based on large and versatile genome coverage. The dendrogram based on the combined data from the different types of markers (RAPD, ISSR and AFLP) was closest to the AFLP-based dendrogram. To evaluate the efficiency of the different marker systems, the sum effective number of alleles (SENA), the average expected heterozygosity for polymorphic markers (Hav(p)), the effective multiplex ratio (E) and marker index (MI) were calculated. The AFLP exhibited considerably high sum effective number of alleles (205.7) compared to RAPD and ISSR (45.1 and 17.8, respectively). The average heterozygosity was also higher in AFLP (0.39) than in RAPD and ISSR (0.36 and 0.35, respectively). The MI was 117.3 in AFLP while it was 95.9 and 10.4 in RAPD and ISSR, respectively. Thus, the results indicated that AFLP is more effective in detecting high level of polymorphism. The correlation coefficient was considerably high between RAPD and ISSR (0.68), and it was lower between RAPD and AFLP (0.23) than that between AFLP and ISSR (0.34). The results confirmed that different marker systems differ in the mechanism of detecting polymorphism, genome coverage and the ease of application. Therefore, they could complement each other to draw more accurate conclusions.
Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards... more Grapevine fanleaf virus (GFLV) is the viral agent of one of the most severe diseases in vineyards worldwide. Survey of grapvine farms in Taif governorate, Mecca province, Kingdom of Saudi Arabia resulted in the detection of Grapevine plants (Vitis vinifera cv. Perelette) exhibited virus-like symptoms of the GFLV. Symptomatic samples were collected to confirm the viral infection through Double antibody sandwich-enzyme linked immunosorbent (DAS-ELISA) assay with Polyclonal antibodies (PAbs) specific to GFLV. Out of 48 tested samples, 43 samples representing 89.6% gave positive reactions with values ranged between 0.116 and 2,462 compared to values ranged between 0.003 and 0.085 of the 5 negative healthy samples. Grapevine plant with high viral titer showed typical fanleaf symptoms such as abnormal branching, double nodes, short Internodes with zigzag growth and fasciations, reduction of the leaves size with deformities and fan-leaf shape. These results were biologically confirmed following the detection of leaves malformation symptoms, mottling, ringspots and systemic chlorotic mosaic, in viral infected Nicotiana benthamiana, Phaseolus vulgaris and Cucurbita pepo, respectively. The inoculated plants developed symptoms 21 days post inoculation. The result obtained by ELISA was confirmed by western blot assay. To our knowledge, this is the first study performed in KSA dealing with the detection of grapevine viruses in naturally infected field-grown vines. Lanes 2-4 are plant viral preparation, lane 1-3 is negative control (healthy plant), (Mr) broad range Farmntas protein marker.
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