AFLP Primer Pairs Research Articles

AFLP Analysis of Genetic Diversity in Indian Soybean [Glycine max (L.) Merr.] Varieties

AFLP technique was used to assess genetic diversity in 72 soybean varieties under cultivation in India. Selected 12 AFLP primer pairs produced 1319 products of which 1257 were polymorphic (95%). Wide variations were observed for the number of amplification products, percent polymorphism and average polymorphism information content (PIC). The Jaccard's similarity indices (J) based on the AFLP profiles of the 72 soybean varieties were subjected to UPGMA cluster analysis. The dendrogram generated revealed four major clusters, which were strongly supported by the high bootstrap values obtained from analyses of 1000 bootstrap samples. In addition, the Mantel's test for cophenetic correlation with r = 0.955 indicated very good fit of the varieties to a group in the cluster analysis. Some correspondence between the clustering pattern and the pedigree, place of release or target area of the variety was observed. Overall moderately high genetic diversity was observed which appears to be due to the higher genetic diversity prevalent in 12 of the varieties included in three diverse clusters and was indicative of the need to include more diverse germplasm in the soybean improvement programs.

AFLP and SSR fingerprinting to evaluate genetic diversity among bread wheat cultivars in Tunisia

Bread wheat ( Triticum aestivum L.) is an economically and nutritionally important cereal crop in the Mediterranean region. Characterization of wheat germplasm by means of DNA fingerprinting techniques provides a tool to assess genetic diversity and to identify varieties. In this study, six Tunisian bread wheat cultivars were characterized by AFLP and SSR markers. Five AFLP primer pairs showed clear different patterns and seems to be the most suitable for analysis of the bread wheat varieties. Three SSR primers were polymorphic with more than two alleles. The pairwise genetic similarities (GS) based on these molecular markers were calculated and used to construct a dendrogram that allowed the discrimination of the six cultivars. The GS among the six varieties ranged from 0.79 to 0.36. The six varieties used in this work clustered into four groups using either AFLP or SSR markers. A high GS was found between Tebecca and Vaga Varieties which have a similar pedigree.

Assessment of testcross performance and genetic diversity of yellow endosperm maize lines derived from adapted × exotic backcrosses

Introduction of exotic maize (Zea mays L.) into adapted tropical germplasm may enhance genetic variability and lead to greater progress from selection. The first objective of this study was to determine if yellow endosperm lines derived from adapted x exotic backcrosses contain exotic alleles that are superior to the recurrent adapted parental line for yield and other agronomic traits in tropical environments. Thirteen exotic yellow maize inbred lines were crossed to an adapted orange line (KUSR) and the F1s were backcrossed to KUSR to generate the first backcrosses. Fifty BC1F4 lines derived from these backcrosses and the recurrent parent were crossed to a common inbred tester (L4001) to form testcrosses, which were evaluated at eight environments in Nigeria. Testcrosses of the BC-derived lines differed significantly for grain yield and other agronomic traits. Only two testcrosses yielded significantly less than L4001 x KUSR, with the best 15 testcrosses producing between 289 and 1,056 kg/ha more grain yield than L4001 x KUSR. The best testcrosses were similar to or better than L4001 x KUSR for other agronomic traits. The second objective of this study was to assess the extent of genetic diversity present among the BC-derived lines. We genotyped 46 BC-derived lines including KUSR and L4001 with 10 AFLP primer pairs and found 491 polymorphic fragments. The average allelic diversity of the lines was 0.30 +/- 0.01. The genetic distance of each BC-derived line from KUSR ranged between 0.49 and 0.91. The average genetic distance for all pairs of the BC-derived lines was 0.68 +/- 0.004, varying from 0.34 to 0.92. The increased grain yield and genetic diversity observed in these studies provide evidence that exotic germplasm can contribute new alleles to expand the genetic base of tropical maize and develop high-yielding hybrids.

Palaeopolyploidy, Spatial Structure and Conservation Genetics of the Narrow Steppe Plant Vella pseudocytisus subsp. paui (Vellinae, Cruciferae)

Vella pseudocytisus subsp. paui (Cruciferae) is a narrow endemic plant to the Teruel province (eastern Spain), which is listed in the National Catalogue of Endangered Species. Two distinct ploidy levels (diploid, 2n = 34, and tetraploid, 2n = 68) have been reported for this taxon that belongs to the core subtribe Vellinae, a western Mediterranean group of shrubby taxa with a chromosome base number of x = 17. Allozyme and AFLP analyses were conducted (a) to test for the ploidy and putative palaeo-allopolyploid origin of this taxon, (b) to explore levels of genetic diversity and spatial structure of its populations, and (c) to address in-situ and ex-situ strategies for its conservation. Six populations that covered the entire geographical range of this taxon were sampled and examined for 19 allozyme loci and three AFLP primer pair combinations. In addition, the gametic progenies of five individuals were analysed for two allozyme loci that showed fixed heterozygosity. Multiple banded allozyme profiles for most of the surveyed loci indicated the polyploidy of this taxon. Co-inherited fixed heterozygous patterns were exhibited by the gametophytic tissues of the mother plants. Both allozyme and AFLP markers detected high levels of genetic diversity, and a strong micro-spatial genetic structure was recovered from AFLP phenetic analyses and Mantel correlograms. Allozyme data support the hypothesis of an allotetraploid origin of Vella pseudocytisus subsp. paui that could be representative of other taxa of the core Vellinae group. AFLP data distinguished three geographically distinct groups with no genetic interaction among them. Allotetraploidy and outcrossing reproduction have probably contributed to maintenance of high levels of genetic variability of the populations, whereas habitat fragmentation may have enhanced the high genetic isolation observed among groups. In-situ microgenetic reserves and a selective sampling of germplasm stocks for ex-situ conservation of this taxon are proposed.

Exploitation of a marker dense linkage map of potato for positional cloning of a wart disease resistance gene

A marker-saturated linkage map of potato was used to genetically map a locus involved in the resistance against wart disease Synchytrium endobioticum race 1. The locus mapped on the long arm of chromosome 4 and is named Sen1-4 in contrast to a Sen1 locus on chromosome 11. The AFLP markers from the Sen1-4 interval enabled the isolation of BAC clones from an 11 genome equivalent BAC library. This was achieved via fingerprinting of BAC pools with the AFLP primer pairs that resemble the genetic marker loci. With non-selective AFLP primers, fingerprints of individual BAC clones were generated to analyse the overlap between BAC clones using FPC. This resulted in a complete contig and a minimal tiling path of 14 BAC clones enclosing the Sen1-4 locus. The BAC contig has a genetic length of approximately 6 cM and a physical length of approximately 1 Mb. Our results demonstrate that map-based cloning of Sen1-4 can be pursued on the basis of a strategy of marker saturation alone. Genetic resolution achieved by screening large numbers of offspring for recombination events may not be required. Together with the construction of the BAC contig, a physical map with the position of the markers is accomplished in one step. This provides proof of concept for the utility of the marker saturation that is offered by the ultra dense AFLP map of potato for gene cloning.

Genetic Relationship of Ornamental Peach Determined Using AFLP Markers

Ornamental peach (Prunus persica (L.) Batsch) is a popular plant for urban landscapes and gardens. However, the genetic relationship among ornamental peach cultivars is unclear. In this report, a group of 51 ornamental peach taxa, originated from P. persica and P. davidiana (Carr.) Franch., has been studied using AFLPs. The samples were collected from China, Japan, and US. A total of 275 useful markers ranging in size from 75 to 500 base pairs were generated using six EcoRI/MseI AFLP primer pairs. Among them, 265 bands were polymorphic. Total markers for each taxon ranged from 90 to 140 with an average of 120. Two clades were apparent on the PAUP–UPGMA tree with P. davidiana forming an outgroup to P. persica, indicates that P. davidiana contributed less to the ornamental peach gene pools. Within P. persica clade, 18 out of 20 upright ornamental peach cultivars formed a clade, which indicated that cultivars with upright growth habit had close genetic relationship. Five dwarf cultivars were grouped to one clade, supported by 81% bootstrap value, indicating that they probably derived from a common gene pool. These results demonstrated that AFLP markers are powerful for determining genetic relationships in ornamental peach. The genetic relationships among ornamental cultivars established in this study could be useful in ornamental peach identification, conservation, and breeding.

Morphology, inheritance and mapping of a compressed lamina mutant of carrot

AbstractA compressed lamina mutant at a locus named COLA was selected in an inbred population of the cultivated carrot Daucus carota sativus Hoffm. Whereas segregation analyses of F2 progenies, as well as corresponding F3 families, indicated a monogenic recessive inheritance, detailed morphological and histological analyses revealed pleiotropic effects of the COLA gene. The mutant plants exhibited a semi‐dwarf phenotype, shortened epidermal and leaf parenchyma cells and significantly reduced lamina dimensions. Furthermore, the mutant developed stipules and hypogynous flowers, contrary to the stipule‐less leaves and epigynous flowers of the wild type. Using bulked segregant analyses, thirty‐nine marker candidates were detected using 180 RAPD primer and 56 AFLP primer pairs. Twelve primers were linked to the COLA locus and mapped in a linkage group with a total length of 44.2 cM. Potential application of the compressed lamina mutant in carrot research is discussed.

DNA Fingerprinting of Clones and Hybrids of American Elm and Other Elm Species with AFLP Markers

Abstract The elms represent a diverse group of widely distributed temperate trees that are valued for forest products as well as landscape plants. Genetic diversity was examined among 43 Ulmus accessions, including 19 accessions of American elm and representatives of seven other species. Data from 135 markers from five AFLP primer pairs were used to estimate genetic similarity among accessions and to construct a UPGMA-derived dendrogram. While the species clusters were generally well-resolved, the relationships among clones and hybrids of American elm were less distinct. Our data provides some evidence to support the hybrid origin of two previously unverified U. parvifolia × U. americana clones, and provides evidence that the new clone N3487 (‘Jefferson’), an elm whose origin has been questioned, is an American elm.

High-resolution mapping and chromosome landing at the root-know nematode resistance locus Ma from Myrobalan plum using a large-insert BAC DNA library.

The Ma gene for root-knot nematode (RKN)resistance from Myrobalan plum (Prunus cerasifera L.)confers a complete-spectrum and a heat-stable resistance to Meloidogvne spp., conversely to Mi-I from tomato,which has a more restricted spectrum and a reduced efficiency at high temperature. This gene was identified from a perennial self-incompatible near-wild rootstock species and lies in cosegregation with the SCAR marker SCAFLP2 on the Prunus linkage group 7 in a 2.3 cM interval between the SCAR SCAL19 and SSR pchgms6 markers. We initiated a map-based cloning of Ma and report here the strategy that rapidly led to fine mapping and direct chromosome landing at the locus. Three pairs of bulks, totaling 90 individuals from half-sibling progenies derived from the Ma-heterozygous resistant accession P.2175, were constructed using mapping data, and saturation of the Ma region was performed by bulked segregant analysis (BSA) of 320 AFLP primer pair combinations. The closest three AFLP markers were transformed into codominant SCARs or CAPS designatedSCAFLP3, SCAFLP4 and SCAFLP5. By completing the mapping population up to 1,332 offspring from P.2175,Ma and SCAFLP2 were mapped in a 0.8 cM interval between SCAFLP3 and SCAFLP4. A large-insert bacterial artificial chromosome (BAC) DNA library of P.2175,totaling 30,720 clones with a mean insert size of 145 kb and a 14-15x Prunus haploid genome coverage was constructed and used to land on the Ma spanning interval with few BAC clones. As P.2175 is heterozygous for the gene, we constructed the resistant and susceptible physical contigs by PCR screening of the library with codominant markers. Additional microsatellite markers were then designed from BAC subcloning or BAC end sequencing. In the resistant contig, a single 280 kb BAC clone was shown to carry the Ma gene; this BAC contains two flanking markers on each side of the gene as well as two cosegregating markers. These results should allow future cloning of the Ma gene in this perennial species.

Monitoring the genetic diversity of three Asian arowana ( Scleropages formosus) captive stocks using AFLP and microsatellites

Asian arowana ( Scleropages formosus) is listed by CITES as a highly endangered fish species. The genetic diversity and population structure of three Asian arowana captive stocks was analyzed using microsatellites and AFLP markers on 32 randomly collected individuals from each stock. Six AFLP primer pairs amplified a total of 324 bands across the three sample sets. The green stock showed the highest percentage of polymorphic bands (15.6%) and expected heterozygosity (0.26), followed by the red (13.0% and 0.24), then the golden one (12.7% and 0.22). Microsatellite analysis showed high allelic and gene diversity in all three varieties. The green stock showed higher allele number (100) and higher gene diversity (0.75) than the red (98 and 0.74) and golden ones (85 and 0.71), respectively. The estimates of long-term effective population size by two different methods ranged from 4741 to 7288 and from 25,056 to 64,641, respectively. Tests of heterozygosity and allele frequency distribution indicate that a recent bottleneck in any of the three captive populations is highly unlikely. Altogether, the data suggest that the captive breeding program for conservation and sustainable use of the endangered Asian arowana will be successful. In addition, we found that the differentiation among populations was intermediate ( F ST=0.047, R ST=0.103) and the genetic distance was the smallest between the green and red, whereas the largest between the red and golden varieties.

Analysis of genetic variation in surviving apple shoots following cryopreservation by vitrification

In vitro grown “Gala” apple shoot tips were successfully cryopreserved by vitrification using a new vitrification solution named PVSL, and the average survival and shoot formation was high, 81 and 77%, respectively. Surviving shoots showed the same regrowth patterns and rate as those of no treatment controls and developed normal shoots and roots. No significant differences ( P<0.05) were observed in morphological characteristics including shoot length, leaf shape, leaf width/length ratio and root length between control and cryopreserved shoots. Adventitious shoots from leaves of cryopreserved shoots could be regenerated with the same rate and frequency as unfrozen controls. No detectable differences were found in soluble proteins and POD isozyme electrophoresis bands between control and cryopreserved shoots. No different RAPD and AFLP fragments were detected between control and cryopreserved shoots using fifteen random primers and six AFLP primer pair. These results show that cryopreservation using vitrification is a practical method for the long-term storage of apple germplasm.

An intraspecific genetic map of velvetbean (Mucuna sp.) based on AFLP markers.

Velvetbean ( Mucuna sp., n=11), a self-pollinated species, is an important legume used in tropical agricultural systems in rotation with other crops for nematode management and/or soil improvement. A genetic map of velvetbean was constructed in order to identify potential molecular markers linked to important morphological and agronomic traits that would be particularly useful for developing and improving the species. Traits such as seed coat color, pod color, and pod pubescence were among the main parameters observed in a process of genetic diversity estimation. Two slightly divergent velvetbean accessions, PI364362 and 'Edgar Farm White', a land race from Alabama, were used to make an intraspecific F(1) hybrid. Amplified fragment length polymorphism analysis (AFLP) detected an average of six polymorphic fragments per primer pair between the two parents. As expected for dominant markers, the sum of all AFLP bands from both parents was generally observed to be present in the AFLP profiles of the F(1) progeny, indicating full penetrance and the dominant nature of AFLP markers. An F(2) population was generated by self-pollinating a single F(1) plant. Using 37 AFLP primer pairs, we detected 233 polymorphic markers of which 164 (70.4%) segregated in 3:1 Mendelian ratios, while the remaining 69 (29.6%) both segregated and were scorable. The genetic linkage map constructed from this population comprised 166 markers, including two morphological traits (pod color and pod pubescence). Twenty linkage groups were found with an average distance between markers of 34.4 cM, covering a total of 687.9 cM. The linkage groups contained from 2 to 12 loci each and the distance between two consecutive loci ranged from 0 to 21.8 cM. The newly designated morphological traits pod color ( pdc) and pod pubescence ( pdp) co-segregated with each other at a distance of 4.2 cM. Two DNA markers designated ACGCAG2 and ACTCTG1 were located in the same group as pdc and pdp. The AFLP linkage map provides opportunities for use in marker-assisted selection and in the detection of loci controlling morphologically important traits.

Genetic variation among asexual progeny of Phytophthora infestans detected with RAPD and AFLP markers

Genotypic variation among 32 single‐zoospore isolates (SZI) of Phytophthora infestans, derived asexually from two hyphal‐tip parental isolates (PI‐105 and PI‐1) of the US‐8 genotype, was assessed with 80 random amplified polymorphic DNA (RAPD) primers and 18 amplified fragment length polymorphic DNA (AFLP) primer pairs. In previous investigations, the SZIs from parental isolate PI‐105 showed high levels of virulence variability and were differentiated into 14 races, whereas the SZIs from PI‐1 showed identical virulence to the parent. The purpose of this investigation was to determine if phenotypic variation observed among SZIs of P. infestans could be detected at the DNA level in these isolates. Polymorphism was detected with 51 RAPD primers and with all 18 AFLP primer pairs in PI‐105 SZIs. In SZIs from PI‐1, polymorphism was also detected with 25 RAPD primers and 17 AFLP primer pairs. Cluster analysis using the unweighted pair‐group method with arithmetic averages (UPGMA) separated the SZIs from parent PI‐105 into six virulence groups, 11 RAPD groups and three AFLP groups. Cluster analysis of PI‐1 SZIs, which all belong to the same virulence group, differentiated them into four RAPD groups and six AFLP groups. No close correlation among RAPD, AFLP and virulence groups could be established within the two progenies of SZIs. Results of this study suggest that there is a considerable level of inherent genetic variability among SZIs derived asexually from the same parental isolate. The possible mechanisms and implications of this genetic variation are discussed.

Identification of Erythroxylum taxa by AFLP DNA analysis

Erythroxylum coca, indigenous to the Andean region of South America, is grown historically as a source of homeopathic medicine. However, in the last century, cultivation of E. coca and several closely-related species for the production of illicit cocaine has become a major global problem. Two subspecies, E. coca var. coca and E. coca var. ipadu, are almost indistinguishable phenotypically; a related cocaine-bearing species also has two subspecies (E. novogranatense var. novogranatense and E. novogranatense var. truxillense) that are phenotypically similar, but morphologically distinguishable. The purpose of this research was to discover unique AFLP DNA patterns (“genetic fingerprinting”) that characterize the four taxa and then, if successful, to evaluate this approach for positive identification of the various species of coca. Of seven different AFLP primer pairs tested, a combination of five proved optimal in differentiating the four taxa as well as a non-cocaine-bearing species, E. aerolatum. This method of DNA fragment separation was selective, and faster, for coca identification, compared with analyses based on flavonoid chemotaxonomy. Using the 5-primer AFLP approach, 132 known and unknown coca leaf accessions were evaluated. Of these, 38 were collected in 1997–2001 from illicit coca fields in Colombia, and all were genetically differentiated from coca originating in Peru and Bolivia. Based on the DNA profiling, we believe that the Colombian coca now represents a hybridization of E. coca var. ipadu. Geographical profiling within Colombia also seems feasible as new coca production areas are developed or new types of coca are introduced within traditional growing areas.

Genetic diversity in an African plantain core collection using AFLP and RAPD markers

Fifteen AFLP primer pairs (EcoRI+3 and MseI+3) and 60 10-mer RAPD primers were used to detect polymorphisms and assess genetic relationships in a sample of 25 plantains from diverse parts of Western and Central Africa. The discriminatory power of the AFLP technique was greater than that of the RAPD technique, since the former produced markers with greater polymorphic information content (PIC) than the latter. Hence, AFLP analysis appeared to be a more-powerful approach for identifying genetic differences among plantain accessions. In this regard, significant genetic diversity within the plantains was shown by the unweighted pair-group method of arithmetic averages (UPGMA) and the multidimensional principal coordinate (PCO) analyses. The AFLP-derived clusters indicated closer relationships between similar inflorescence types than the RAPD-derived clusters. A small group of cultivars from Cameroon were separated from the bulk of other plantains, suggesting that Cameroon may harbour accessions with useful or rare genes for widening the genetic base of breeding populations derived from the plantains. A greater effort should be directed at collecting and characterizing plantain cultivars from Cameroon.

Analysis of the wild potato germplasm of the series Acaulia with AFLPs: implications for ex situ conservation.

The wild potato germplasm of the series Acaulia maintained at the Centre for Genetic Resources, The Netherlands, currently consists of 314 accessions. This collection comprises seed samples of the species Solanum acaule (ssp. acaule, ssp. aemulans, ssp. palmirense and ssp. punae) and Solanum albicans collected from South America. In order to validate taxonomic classification, to investigate the extent of redundancy and to study the distribution of genetic diversity across the collection area, the entire collection was analysed with two AFLP primer pairs on two plants per accession. Within the entire sample a total number of 130 polymorphic bands were scored for the two primer pairs. An UPGMA cluster analysis grouped the majority of plants according to the species and subspecies. A total number of 16 misclassifications were identified, including four cases that did not seem to belong to the series Acaulia. Two accessions were found to consist of plants of different AFLP clusters. AFLP data also allowed the taxonomic classification of the subspecies of 97 accessions that previously were described as S. acaule only. For 126 accessions the two individuals studied displayed identical AFLP profiles. Forty six of these 126 accessions shared their profiles with both or single plants of other accessions. These were all tested for identical profiles for a third primer pair, resulting in 15 duplication groups consisting of a total number of 22 accessions and 14 single plants. Analyses of molecular variance (AMOVA) were performed to examine the distribution of genetic variation. Comparison of geographic distances between the collection site of plants and the number of AFLP polymorphisms revealed no consistent relationship between geographic distance and genetic diversity. AFLP analysis appeared to be an efficient method to verify taxonomic classification and to identify redundancies in the wild germplasm of the series Acaulia. Implications of the results for the ex situ conservation of wild potato germplasm are discussed.

Genetic dissection of a modern sugarcane cultivar (Saccharum spp.). I. Genome mapping with AFLP markers

Sugarcane cultivars are polyploid, aneuploid clones derived from interspecific hybridization between Saccharum officinarum and S. spontaneum. Their genome has recently started to be unravelled as a result of the development of molecular markers. We constructed an AFLP genetic map based on a selfing population of a specific cultivar, R570.Using 37 AFLP primer pairs, we detected 1,185 polymorphic markers of which 939 were simplex (segregated 3:1); these were used to construct the map. Of those 939, 887 were distributed on 120 cosegregation groups (CGs) based on linkages in coupling, while 52 remained unlinked. The cumulative length of all the groups was 5,849 cM, which is probably around one-third of the total genome length. Comparison with reference S. officinarum clones enabled us to assign 11 and 79 CGs to S. spontaneum and S. officinarum,respectively, whereas 11 CGs were probably derived from recombination between chromosomes of the two ancestral species. The patchy size of the groups, which ranges from 1 to 232 cM, illustrates the difficulty to access large portions of chromosomes, particularly those inherited from S. officinarum. Repulsion phase linkages suggested a high preferential pairing for 13 CG pairs. Out of the 120 CGs, 34 could be assigned to one of the 10 homo(eo)logy groups already defined in a previous RFLP map owing to the use of a small common marker set. The genome coverage was significantly increased in the map reported here. Implications for quantitative trait loci (QTL) research and marker-assisted breeding perspectives are discussed.

AFLP-based genetic diversity assessment amongst agronomically important natural and some newly synthesized lines of Brassica juncea

AFLP markers were employed to assess the genetic diversity amongst 21 established natural and nine synthetic varietes and lines of Brassica juncea originating from Asia, Australia, Canada, Eastern Europe and Russia. Six of the synthetics used for diversity studies have been developed recently. Twenty one EcoRI/MseI-based AFLP primer pairs generated a total of 1251 scorable fragments among the 30 genotypes studied, of which 778 bands were polymorphic with an average of 37 polymorphic bands per primer pair. On the basis of the similarity coefficients (F value), cluster analysis was performed using the UPGMA method. The 30 B. juncea lines could be grouped into three distinct clusters. All the Indian, Chinese and previously developed synthetics formed one cluster (cluster A), the recently developed synthetics formed a separate cluster (cluster B) and the lines from Australia, Canada, Eastern Europe and Russia formed the third cluster (cluster C). A majority of the lines were uniquely identified by one or more primer pairs due to the presence or absence of variety specific band(s). Four primer pairs were found to be most informative, since these uniquely identified all the genotypes assayed. These four primer pairs, could therefore be used as fingerprinting primers for varietal identification.

Evaluation of genetic relationships among botanical varieties of cultivated peanut (Arachis hypogaea L.) using AFLP markers

Forty-four accessions of cultivated peanut (Arachis hypogaea L.) representing sixbotanical varieties of two subspecies along with three accessions ofthe wild relative A. monticola Krapov et Rigoni were evaluated for their genetic relationships using theAFLP marker technology. Fifteen AFLP primer pairs (EcoRI/MseI) generated 28distinct polymorphic markers that were employed to develop uniqueprofiles of all accessions and to construct a phenogram. The resultsshowed that the botanical varieties aequatoriana and peruviana werecloser to subspecies hypogaea than subspeciesfastigiata Waldr. to which they belong, and the wildA. monticola was notdistinct from the cultivated A.hypogaea. Although the extent of geneticdiversity in peanut is low compared to many other crops, our studiesshow that by employing the AFLP approach, sufficient DNA variationcan be detected in the cultivated peanut germplasm to conductevolutionary studies.

A new aspect of genetic diversity of Indonesian oil palm (Elaeis guineensis Jacq.) revealed by isoenzyme and AFLP markers and its consequences for breeding

Oil palm (Elaeis guineensis Jacq.) plays an important economic role in some countries of Southeast Asia like Indonesia, which is the world’s second producer of palm and palm kernel oil. The quality improvement of planting material needs a better understanding of the genetic relationships between genotypes from different populations used in the breeding programmes. In this study, 48 parents, representative of four populations used in Indonesian Oil Palm Research Institute (IOPRI) breeding programmes, were analysed with five selected AFLP primer pairs and four isoenzymatic systems. One hundred and fifty eight scorable band levels were generated of which 96 (61%) were polymorphic. AFLP allowed us to identify off–type descendants which were excluded from analysis. The use of unbiased Rogers distance clearly separated the four studied populations. The Neighbor-Joining method re-groups two African populations which are known as originating from different regions. Nevertheless, the variability revealed is in accordance with oil palm breeders’ knowledge. The results obtained with AFLP showed that the crosses among the African sub-population, which is excluded in oil palm reciprocal recurrent selection (RRS) breeding programmes, may be more interesting than the crosses between the African and the Deli populations.