رديابي ژن هاي مقاومت به سفيدك پودري سيب در ژنوتيپ هاي وحشي سيب ايران

چكيده انگليسي :

86 Detection of Resistance Genes to Powdery Mildew in Iranian Wild Apple Genotypes Mehdi Jamalvand mehdijamalvand@gmail com September 17 2016 Department of Plant Protection Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language Farsi Supervisor B Sharifnabi sharifna@cc iut ac ir Abstract Apple Malus domesticca Borkh is one of the most valuabale plant in Rosaceae family because of its high nutritional and economical value is considered as one of the important agricultural products Apple plants are attacked by several fungal diseases Apple Scab and Powdery mildew bacterial diseases Fire blight Viral disease Apple mosaic and nematode root knot In which Powdery mildew damage is the second important after apple scab At the end of season by increasing buds infection Primary inoculum will increase in next spring and also by suppressing flower bud formation decreasing and highly damage in yield will occur Powdery mildew caused by the obligate biotrophic ascomycete fungus Podosphaera leucotricha is one of the main fungal diseases in commercial apple production which causes an extensive economic losses due to the negative impact on quality and quantity of apple production Dinocap benomyl noarymol are pesticides used to control it but due to high costs and environmental problems the use of these pesticides were faced with doubts In recent years the use of resistant cultivars for controling powdery mildew of apple has been considered For this purpose the genes Pl1 Pl2 Pld Plw Plbj etc as well as RGA Resistance Gene Analogs candidate resistance genes were identified in wild genotypes In order to detect the presence of resistance genes to the fungus P leucotricha 47 genotypes of wild apples during 2014 to 2015 were collected DNA extracted from young leaves and then SCAR and Degenerate primer pairs were used Sequences of the genes Pl1 Pld and Plbj in the World Database BLAST did not alighn or its results only showed similarity with mRNA apple or pear But alighnment related to the RGA in the database NCBI in studied genotypes was confirmed NBS LRR domains conserved and P loop NTPase motif in NBS LRR like protein which encode by the RGA in N terminal were confirmed in wild apple genotypes of Iran The most common reaction catalysed by enzymes of the P loop NTPase fold is the hydrolysis of the beta gamma phosphate bond of a bound nucleoside triphosphate NTP The energy from NTP hydrolysis is typically utilised to induce conformational changes in other molecules which constitutes the basis of the biological functions of most P loop NTPases This motif contained two motifs Walker A and Walker B which eventually leading to cell death in animals and plants Proteins that are encoded by the RGA all with motifs that play a role in pathogenicity pathways signaling in the host plants regulation of gene expression transcription cell death program and the innate immune system Due to the lack of information about the sequences of resistance genes in gene banks which induce resistance to powdery mildew by Pld and Pl1 gene and Plbj gene which induce resistance to both powdery mildew and scab in apple the gene sequences could be registered and these genes alongwith the RGAs could be used in Iranian apple breeding programs Keywords Powdery mildew Podosphaera leucotricha Resistance genes RGA

جمالوند، مهدي

رديابي ژن هاي مقاومت به سفيدك پودري سيب در ژنوتيپ هاي وحشي سيب ايران

Podosphaera leucotricha , RGA