Contrastant banana accessions for resistance to the burrowing nematode, based on molecular markers RAPD

Abstract

This work aimed to proceed molecular characterization of seven banana accessions (Borneo, Grand Naine, 1304-06, 4249-05, 0337-02, 0323-03 and 4279-06) resistance to the nematode Radopholus similis. These accessions were selected taking in account the reproduction factor (RF) among 26 banana genotypes from a working collection belonging to Embrapa Mandioca e Fruticultura Tropical.The genomic DNA of the seven accessions was extracted, and 36 decamere primers had been used to obtain RAPD markers. The resulting markers were converted into a matrix of binary data. From that matrix the genetic distance between the accessions were estimated, for further clustering and graphic dispersion analyses. From a total of 521 RAPD markers generated, 420 (81%) were polymorphic, including 140 (27%) potentially promising for application on works related to genetic mapping of the resistance to R. similis. OPE-15, OPH-17, and OPG-09 were the primers that contributed to the highest number of bands promising for genetic mapping of resistance (12, 8, and 8, respectively). The genetic distances between accessions ranged from 0.106 to 0.455, with the longest one observed between cv. Borneo and the genotype 4279-06, considered as highly susceptible and resistant, respectively, to the nematode according to the RF. The graphic dispersion distinguished three groups of accessions, and most of resistant genotypes clustered together in the same group. The most contrastant genotypes for resistance (Borneo and 4249-05) were separated by a genetic distance of 0.374, and possessed a total of 114 polymorphic bands promising for genetic mapping of resistance. In addition, the results of pathogenicity tests were congruent with those obtained by RAPD analyses.

Clonal fidelity investigation of micropropagated hardened plants of jackfruit tree (Artocarpus heterophyllus L.) with RAPD markers

“…This is proposed that DNA bands probably characterize repetitive sequences [23,40]. The variation and or polymorphism in repetitive DNA sequences has normally been detected during plant tissue culture studies [57,65]. The tissue culture stress may give rise to deviations at privileged sites, like repetitive DNA, thereby stimulating transposons.…”

Phytoparasitic Nematodes of Musa spp. with Emphasis on Sources of Genetic Resistance: A Systematic Review

“…Nematode management in banana plantations relies mainly on the use of chemical nematicides. However, in addition to being expensive, nematicides can cause environmental degradation, have the potential to leave residues on fruits, contaminate groundwater, and affect non-target organisms, and pose a risk of toxicity to applicators [27][28][29]. Cultural control measures, such as rhizome cutting followed by hot water treatment, and the use of healthy shoots or clean planting material, such as those from tissue culture, offer only temporary nematode management, as fields are usually reinfested [30,31].…”

Banana horizontal and vertical resistance to the burrowing nematode depends on the level of aggressiveness or virulence of the nematode population

“…have indicated direct correlations between the number of burrowing nematodes in banana roots and root damage (FALLAS et al, 1995;MARIN et al, 1999;MOENS, 2004;SANTOS et al, 2013). Therefore, quantifying R. similis population levels in roots may be used to determine differences in aggressiveness among populations.…”

“…Dochez et al (2009) assessed the progeny resulting from a cross between the diploid hybrids TMB2 x 6142-1 and TMB2 x 8075-7 and found that two dominant genes controlled resistance, named A and B, both with additive and interactive effects, by which the recessive bb suppresses the dominant A. Moreover, genetic differences among R. similis populations in Musa accessions have been detected by DNA markers and phenotype evaluations (COSTA et al, 2008;SANTOS et al, 2010). Melo and Santos (1999) tested a modified version of Griffing model IV (GRIFFING, 1956) that provides simplified information on horizontal and vertical resistance on the host and pathogen virulence and aggressiveness.…”