Eucalyptus is the premier paper pulp, short rotation plantation species grown all over the world. Genetic improvement programs integrating molecular marker tools are in progress in many parts of the globe to increase the productivity. Whole genome sequence and expressed sequence tags (ESTs) of the eucalypts paved way for introduction of molecular genetics and breeding in this genus. Different molecular characterization approaches have been used simultaneously in eucalypts, however, microsatellites or simple sequence repeats (SSRs) with their prolific characteristics could occupy a special niche in Eucalyptus genetic improvement. Further, highly informative SSRs were used for the clonal identity, genetic fidelity and in certification of breeder’s rights. Eucalyptus genetic linkage maps generated with microsatellite loci were used successfully to identify quantitative trait loci (QTLs) for various economically important traits. Progressively more numbers of microsatellites are being linked to genes associated with adaptive and functional variations, therefore making their utility broader in genetic applications. Availability of common SSR markers across the species provides an opportunity to validate the expression of QTLs across variable genetic backgrounds and accurately compare the position of QTLs in other species. Recent evidences suggest that the presence of SSRs in micro RNAs of plant species play a role in the quantitative trait expression. Similar studies in eucalypts may provide new insights into the genetic architecture of transcript-level variations and post transcriptional gene regulation. This review on eucalypts microsatellites, highlights the availability and characteristics of genomic and eSSRs and their potential in genetic analysis of natural and breeding populations and also discusses the future prospects in population genetics and marker assisted selection.Electronic supplementary materialThe online version of this article (doi:10.1186/s40529-014-0073-3) contains supplementary material, which is available to authorized users.

Eucalyptus is an important industrial species with tolerance to drought and salt stress. Genetic improvement activities including quantitative trait loci (QTL) mapping for pulping and adventitious rooting traits are in progress, but no information is available on the genomic regions on adaptive traits such as stomatal characteristics. In this study, an interspecific cross between Eucalyptus tereticornis and E. grandis was generated for the development of genetic map and QTL identification for stomatal traits. Simple sequence repeats (SSRs), inter-simple sequence repeats (ISSRs) and sequence related amplified polymorphism (SRAP)markers were used for genotyping the F1 individuals. Parent-specific geneticmaps (female, 1023.56 cM;male, 1049.64cM) and consensus map (1049.4 cM) were developed. QTL analysis was carried out to identify the chromosomal regions affecting stomatal density, area and pore length in adaxial and abaxial leaf surface. Seven QTLs were identified with phenotypic variation of 11.36 to 27.30% for stomatal density, area and pore length. Correlation of stomatal traits when combined with growth and wood properties would have greater implications for generation of stress tolerant eucalypt hybrids with higher productivity and adaptability.

The eucalypt species, and, show tolerance to drought and salinity conditions, respectively, and are widely cultivated in arid and semiarid regions of tropical countries. In this study, genetic linkage map was developed for interspecific cross × using pseudo-testcross strategy with simple sequence repeats (SSRs), intersimple sequence repeats (ISSRs), and sequence-related amplified polymorphism (SRAP) markers. The consensus genetic map comprised totally 283 markers with 84 SSRs, 94 ISSRs, and 105 SRAP markers on 11 linkage groups spanning 1163.4 cM genetic distance. Blasting the SSR sequences against sequences allowed an alignment of 64% and the average ratio of genetic-to-physical distance was 1.7 Mbp/cM, which strengths the evidence that high amount of synteny and colinearity exists among eucalypts genome. Blast searches also revealed that 37% of SSRs had homologies with genes, which could potentially be used in the variety of downstream applications including candidate gene polymorphism. Quantitative trait loci (QTL) analysis for adventitious rooting traits revealed six QTL for rooting percent and root length on five chromosomes with interval and composite interval mapping. All the QTL explained 12.0-14.7% of the phenotypic variance, showing the involvement of major effect QTL on adventitious rooting traits. Increasing the density of markers would facilitate the detection of more number of small-effect QTL and also underpinning the genes involved in rooting process.

-The genus Eucalyptus encompasses several species of industrial importance. Many of these species have been subjected to genetic characterization using different kinds of DNA markers. More than 1000 microsatellites have been identifi ed from the genome of eucalypts and they are highly amenable for cross species transferability. During cross amplifi cation of microsatellites, homoplasy is reported in many species in which although the allele size might be the same, the sequences are not. Thus, it is essential to ascertain the DNA sequence homology with source and target microsatellite repeats. Accordingly, fifty five alleles from six microsatellite loci (ECc1, ECc2, Eg61, Embra100, Embra1468 and Embra2002) were amplifi ed in two inter-specifi c hybrid populations (Eucalyptus tereticornis × E. grandis and E. tereticornis × E. camaldulensis) and sequenced. The results showed that all the microsatellite loci were amplifying the target repeat types except for the loci Eg61 and Embra2002. The locus Eg61 has target repeat of (CAA)(GAT) but the sampled alleles had either (CAA)(GAT) or (GAT) alone. Similarly, the Embra2002 locus was targeting interrupting repeats of (CCA)..(CCA), but the sequenced alleles had repeats of (CCA) with or without interruption. Nevertheless, the allele size estimated in electrophoresis for hybrids was in conformity with that of the parent alleles. This study suggests the need for validation of the repeat characteristics of microsatellites by sequencing of the alleles particularly in cross species amplifi cation.

This study analyses the status of electronic resources facilities and services provided by the Engineering Colleges in Chennai. It also discusses the purpose of using e-resources, benefits, subject coverage, students satisfaction, problems that are faced by the Engineering College students while accessing e-resources .The study was limited to only four engineering colleges situated on the line to OMR road, Chennai. Majority of the students are accessing the e-resources from their Central Library followed by their home (17%), Internet centre (13%) and from their department libraries (10%). Since the student community has to depend on the e-resources for their academic endeavour, the libraries should subscribe the e-resources as per the required norms to fulfill the academic needs of the student community.