Eucalyptus is an important short rotation pulpy woody plant, grown widely in the tropics. Recently, many genomic programmes are underway leading to the accumulation of voluminous genomic and expressed sequence tag sequences in public databases. These sequences can be utilized for analysis of simple sequence repeats (SSRs) and single nucleotide polymorphism (SNPs) available in the transcribed genes. In this study, in silico analysis of 15,285 sequences representing partial and full-length mRNA from Eucalyptus species for their use in developing SSRs or microsatellites were carried out. A total of 875 EST-SSRs were identified from 772 SSR containing ESTs. Motif size of 6 for dinucleotide and 5 for trinucleotide, tetranucleotide, and pentanucleotides were considered in locating the microsatellites. The average frequency of identified SSRs was 12.9%. The dinucleotide repeats were the most abundant among the dinucleotide, trinucleotide and tetranucleotide motifs and accounted for 50.9% of the Eucalyptus genome. Primer designing analysis showed that 571 sequences with SSRs had sufficient flanking regions for polymerase chain reaction (PCR) primer synthesis. Evaluation of the usefulness of the SSRs showed that EST-derived SSRs can generate polymorphic markers as all the primers showed allelic diversity among the 16 provenances of E. tereticornis.

Inter simple sequence repeat polymerase chain reaction (ISSR-PCR) was used for the genetic analysis of the six species of Allocasuarina, five species of Casuarina and 12 superior performing selections of C. equisetifolia L. We also fingerprinted C. equisetifolia L. selections using Fluorescent-ISSR-PCR (FISSR-PCR), an improvised ISSR-PCR assay. The ISSR analysis provided information on the frequency of various simple sequence repeats in the casuarina genome. The di-nucleotide repeats were more common, among which (CA) n and its complementary nucleotide (GT) n repeat motifs amplified relatively higher number of bands with an average of 6.0 ± 3.5 and 6.3 ± 1.8 respectively. Eleven species of casuarinas were amplified with 10 primers anchored either at 5¢ or 3¢ end. A total of 253 PCR products were obtained and all were polymorphic, out of which 48 were specific to Allocasuarina and 36 were specific to Casuarina genus. Genetic similarity among the species was 0.251. A UPGMA dendrogram grouped all the Casuarina species together. The 12 superior performing selections of C. equisetifolia L. produced 57 polymorphic ISSR markers while the FISSR assay revealed 105 polymorphic markers. The primer CRR(ATT) 4 distinguished all the selections. DNA profiles obtained with ISSR and FISSR assays would serve as a reference library for the establishment of clonal identity in casuarinas.

This paper proposes novel carry select and carry look-ahead BCD adders using reversible logic. Reversible logic gates are widely known to be compatible with future computing technologies which virtually dissipate zero heat. Adders are fundamental building blocks in many computational units. For this reason, we have simulated several adder circuits using the reversible gates. Among all the other adders, the main virtue of BCD adders is that it allows easy conversion to decimal digits for printing or display and faster decimal calculations. These reversible BCD circuits are basis of the decimal ALU of primitive Quantum CPU. The proposed BCD adders have been simulated in VLSI and static timing report was analyzed.

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Casuarina equisetifolia is one of the most extensively introduced tree species outside its natural range and is a true multipurpose species, providing a range of services and products for industrial and local end users.