RAPD

About: RAPD is a research topic. Over the lifetime, 15960 publications have been published within this topic receiving 360391 citations.

Inheritance and linkage of a gene for resistance to race 4 of fusarium wilt and RAPD markers in chickpea

Abstract: Several races of Fusarium oxysporum Schlechtend:Fr f sp ciceris (Padwick) Matuo and K Sato cause economic losses from wilting disease of chickpea ( Cicer arietinum L) While the genetics of resistance to race 1 have been reported, little is known of the genetics of resistance to race 4 We undertook a study to determine the inheritance of resistance and identified random amplified polymorphic DNA markers (RAPDs) linked to the gene for resistance For the investigation, we used 100 F5 derived F7 recombinant inbred lines (RILs) that had been developed from the cross of breeding lines C-104 x WR-315 Results indicated that resistance is controlled by a single recessive gene The RAPD markers previously shown to amplify fragments linked to race 1 resistance also amplified fragments associated with race 4 resistance The RAPD loci, CS-27700, UBC-170550 and the gene for resistance to race 4 segregated in 1:1 ratios expected for single genes Both RAPD markers were located 9 map units from the race 4 resistance locus and were on the same side of the resistance gene Our results indicated that the genes for resistance to race 1 and 4 are 5 map units apart The need to determine the genomic locations of race specific resistance genes and the possibility that these genes are clustered to the same genomic region should be investigated

Analysis of genetic diversity and relationships in East African banana germplasm

Abstract: The genetic diversity and phylogenetic relationships of 29 East African highland banana (Musa spp.) cultivars and two outgroup taxa, M. acuminata Calcutta 4 and Agbagba were surveyed by RAPD analysis. A genetic similarity matrix was established based on the presence or absence of polymorphic amplified fragments. Phylogenetic relationships were determined by UPGMA cluster analysis. RAPDs showed that the highland bananas are closely related with a narrow genetic base. Nevertheless, there were sufficient RAPD polymorphisms that were collectively useful in distinguishing the cultivars. The dendrogram was divisible into a major cluster composed of all the AAA highland banana cultivars and Agbagba (AAB) and a minor cluster consisting of Kisubi (AB), Kamaramasenge (AB) and Calcutta 4 (AA). Several subgroups are recognized within the major cluster. RAPD data did not separate beer and cooking banana cultivars. Our study showed that RAPD markers can readily dissect genetic differences between the closely related highland bananas and provide a basis for the selection of parents for improvement of this germplasm.

Genetic stability in micropropagated Cleome gynandra revealed by SCoT analysis

Abstract: A newly developed and novel DNA marker technique, i.e. start codon targeted (SCoT) polymorphic markers that target plant gene regions were used to assess genetic stability of in vitro raised plants of Cleome gynandra multiplied by enhanced bud proliferation from nodal segments. Seven randomly selected micropropagated plants, following at least 2 months of growth in the greenhouse along with mother plant were subjected to molecular analysis. Of 24 primers screened, 15 primers produced unambiguous and reproducible bands. All 15 primers generated a total of 65 fragments, with a mean of 4.3 ranging 2–7 per primer. No polymorphism was detected in regenerated plants and the mother plant, revealing the genetic fidelity of the in vitro raised plantlets. To verify the results of SCoT analysis, random amplified polymorphic DNA (RAPD) markers were also used for the assessment of genetic fidelity of tissue culture raised plants. The monomorphic banding pattern in micropropagated plants and the mother plant obtained from SCoT and RAPD analysis confirms the genetic stability of the in vitro raised plants and demonstrates the reliability of our micropropagation system for C. gynandra, an important C4 plant.

Bias Caused by Using Different Isolation Media for Assessing the Genetic Diversity of a Natural Microbial Population.

Abstract: The influence of isolation medium on the biodiversity of Burkholderia cepacia strains recovered from the rhizosphere of Zea mays was evaluated by comparing the genetic diversity of isolates obtained by plating serial dilutions of root macerates on the two selective media TB-T and PCAT. From each medium, 50 randomly chosen colonies were isolated. On the basis of the restriction patterns of DNA coding for 16S rRNA (16S rDNA) amplified by means of PCR (ARDRA), all strains isolated from TB-T medium were assigned to the B. cepacia species, whereas among PCAT isolates only 74% were assigned to the B. cepacia species. Genetic diversity among the PCAT and TB-T isolates was evaluated by the random amplified polymorphic DNA (RAPD) technique. The analysis of molecular variance (AMOVA) method was applied to determine the variance component for RAPD patterns. Most of the genetic diversity (90.59%) was found within the two groups of isolates, but an appreciable amount (9.41%) still separated the two groups (P < 0.001). Mean genetic distances among PCAT isolates (10.39) and TB-T isolates (9.36) were significantly different (P < 0.0001). The results indicate that the two different isolation media select for B. cepacia populations with a different degree of genetic diversity. Moreover, a higher degree of genetic diversity was observed among strains isolated from PCAT medium than among those isolated from TB-T medium.