DNA fingerprinting analysis of Eucalyptus species

Silvae Genetica

The improvement of Eucalyptus clones plays a crucial role in modern silviculture. This study used a set of 17 microsatellite loci to analyze the genetic diversity and structure of 107 elite clones (80 E. grandis and 27 E. globulus). All clones were cultivated in Uruguay and were sourced from three different providers. Using the fingerprinting technique, an exclusive molecular profile was assigned for each clone, and the genotyping reaction showed differences between the two species. The cumulative probability of identifying two random individuals that share the same genotype (PI) with all 17 loci, was estimated as low for E. grandis (1.18×10-15) and E. globulus (4.03×10-14). The combined PIsibs was (1.05×10-5) and (2.17×10-5) for E. grandis and E. globulus, respectively. A total of 180 alleles were detected for E. grandis and 100 for E. globulus. We found a high mean number of alleles per locus (10 for E. grandis and 6 for E. globulus), and the results for mean polymorphic informati...

Temas Agrarios, 2017

One of the main problems faced in several eucalypt breeding programs is the difficulty to identify the species and hybrids. This study aimed to find molecular markers associated with five species of Eucalyptus (E. saligna, E. tereticornis, E. urophylla, E. grandis and E. brassiana), by AFLP (Amplified Fragment Length Polymorphism) markers and BSA (Bulk Segregant Analysis), for their use in breeding programs in Brazil. In 33 primer combinations, a total of 868 polymorphic fragments was obtained, which represent a 91.65% of polymorphism. The best combinations that show potential markers for species identification were the primers M + GGT / E + ACC, which was linked to 70% of E. urophylla individuals. However, primer combination composed of M+GGA/E+ACC identified 60% of individuals in the E. saligna species; combination by the primers M+GTC/E+AAC, confirmed two marks, one in 60% and the other in 50% of E. grandis individuals in the identification test. The treatment composed by the primers M+GGC/E+AAA, was confirmed in only 30% of E. brassiana individuals, being the same for the combination M+GGC/E+ACC primers, identifying 30% of E. tereticornis individuals. The AFLP analysis and BSA provide a quick tool for the identification of cultivars in Eucalyptus and can also be used to assist forest breeding programs.

The genus Eucalyptus includes over 700 species, some of which are the most widely planted hardwoods worldwide. Each species of Eucalyptus present different characteristics regarding its wood quality and yield. This fact makes it very important to work with known species to optimize handling and conservation of forest resources. Some of them are morphologically similar, making it difficult to differentiate by simple observation. An alternative approach is to develop molecular methods for the species differentiation. Using a Bulk Segregant Analysis (BSA) with 59 RAPD (Random-Amplified Polymorphic DNA) primers of Operon Technologies Inc. Kits, polymorphic DNA fragments between Eucalyptus species were isolated and SCAR (Sequence Characterized Amplified Regions) markers designed for Eucalyptus saligna and Eucalyptus tereticornis.

Silvae Genetica

Eucalyptus is planted worldwide for raw material in paper and rayon industry. It is a potential out-crosser and the natural populations are highly heterogeneous displaying strong inbreeding depression. Eucalyptus hybrids have been intensively utilized for their vigor, higher wood quality and resistance to diseases. Identification of species for hybridization is predominantly based on morphological characters and is not always reliable. Hence, DNA marker based species identification and hybrid validation is an important and efficient tool in breeding programs. In the present study, attempts were made to identify species - diagnostic markers for six eucalypt species (E. camaldulensis Dehnh, E. citriodora Hook, E. grandis W. Hill ex Maiden, E. pellita F. Muell, E. tereticornis Sm and E. urophylla S.T. Blake) using ISSR-PCR fingerprints. PCR amplification using seven ISSR primers resulted in significant polymorphism among the population from different species. E. citriodora and E. teret...

Eucalyptus grandis e Eucalyptus grandis E. urophylla, no qual os cruzamentos foram estabel- ecidos em estudo anterior com base na diversidade genética utilizando marcadores molecu- lares RAPD. Foram avaliados 17 locos microssatélites que resultaram na amplificação de 75 formas alélicas com valor de heterozigose média de 26,14% (considerada baixa). Os valores de distância genética variaram de 10 a 100% e a média geral de dissimilaridade foi de 64,62% (considerada elevada). A análise de agrupamento dos 40 genitores revelou elevada diversidade e dois grupos espécie-específicos, apesar de alguns genótipos estarem fora de seu grupo espécie-específico. Comparando-se com os grupos formados pelos mar- cadores RAPD, os marcadores microssatélites foram mais eficientes na discriminação das espécies. Valores de correlação entre marcadores RAPD e microssatélites foram baixos e/ou negativos. Marcadores microssatélites foram eficientes na discriminação de genitores de E. grandis e grandis e grandi...

Tropical Plant Research, 2017

Under 'Hariyali Prasar Yojna' Chhattisgarh State Forest Department has procured and planted elite eucalyptus clones on large scale in different forest circles/divisions of the state during the monsoon of 2015-16 and 2016-17. To assess the genetic homogeneity of the supplied clones, genetic fidelity testing of the procured clones was carried out using ISSR marker. The monomorphic pattern of ISSR profiles observed for the ramets of the respective clones in comparison with their mother plant confirmed the genetic purity. This also demonstrates the application of molecular marker technology for quality control in social forestry plantation.

Plant …, 2010

Background: A number of molecular marker technologies have allowed important advances in the understanding of the genetics and evolution of Eucalyptus, a genus that includes over 700 species, some of which are used worldwide in plantation forestry. Nevertheless, the average marker density achieved with current technologies remains at the level of a few hundred markers per population. Furthermore, the transferability of markers produced with most existing technology across species and pedigrees is usually very limited. High throughput, combined with wide genome coverage and high transferability are necessary to increase the resolution, speed and utility of molecular marker technology in eucalypts. We report the development of a high-density DArT genome profiling resource and demonstrate its potential for genome-wide diversity analysis and linkage mapping in several species of Eucalyptus.

Tree Physiology, 2005

Eucalyptus is the most economically important hardwood plantation tree cultivated in tropical and subtropical countries. Inter-simple sequence repeat (ISSR) markers were used to evaluate genetic relationships within and between individuals of six Eucalyptus species. A total of 583 loci (265 to 1535 bp) were amplified from 149 individuals belonging to the six Eucalyptus species using seven ISSR primers (two to three nucleotide repeats anchored with one or two nucleotides at the 3′ or 5′ region). The ISSR fragments indicated significant polymorphism and genetic diversity among the individuals. Cluster analysis and principal component analysis revealed the occurrence of wide genetic diversity among populations of E. tereticornis Sm., E. camaldulensis Dehnh. and E. urophylla S.T. Blake and narrow genetic diversity among populations of E. citriodora Hook. and E. grandis W. Hill ex Maiden. Genetic diversity was high in E. tereticornis Sm. (47.27%) and low in E. citriodora (18.64%). Maximum Nei's genetic identity (0.897) was observed between E. camaldulensis and E. tereticornis species, whereas maximum genetic diversity (0.286) was found between individuals of E. citriodora and E. grandis.

Heredity, 1997

Eucalyptus graniticola is known from a single plant located on a granite outcrop south-east of Perth in Western Australia. Since its discovery in 1987, it has been uncertain whether this eucalypt is a relict species or a hybrid and, consequently, further study is required in order to devise appropriate conservation strategies. The similarity of features, such as leaf, bud and fruit morphology, to those of E. rudis, a common tree found in the vicinity, suggested that E. graniticola is a hybrid. This study uses random amplified polymorphic DNA (RAPD) analysis to demonstrate the additive inheritance of DNA markers from E. rudis and E. drummondii, the putative parent species, in E. graniticola. All the markers detected for E. graniticola using nine primers were shared with either E. rudis (40 per cent), E. drummondii (35 per cent) or both parent species (25 per cent). The DNA fingerprinting results, combined with other factors, such as the segregation of cotyledon morphology, demonstrate the hybrid origin of E. graniticola. As a result, conservation of this rare eucalypt should rely more on ex situ propagation and storage than on active management.