Breeding vis a vis Genomics of Tropical Tree Crops
Tree breeding is thought to have a pragmatic future. In the backdrop of climate change and exponential increase in population, developing plants, especially trees, resilient to unpredictable environmental conditions is more challenging than ever before. The benefits of tree species, especially fruit trees are multifold for the sustenance of humankind. Tree genotypes are selected and breeding values estimated for superior characteristics following long term and costly field based progeny trials, where provenance trials, clone trials and full sib progeny evaluations are the backbone of such experiments. Of late, efforts are on to manipulate functions at the level of gene and genome of tree species. The shift from traditional Sanger sequencing to massive parallel sequencing of millions of short DNA pieces simultaneously through Next Generation Sequencing (NGS) is a major breakthrough in the last decade. Among the DNA markers, microsatellites (SSRs Simple Sequence Repeats of 2 6 bases) which tend to be highly polymorphic, locus specific and co dominant are preferred in Marker Assisted Selection (MAS) and genetic linkage map construction. Reverse genetics, gene silencing through RNA interference (RNAi) Transcript profiling (DNA microarrays) Serial Analysis of Gene Expression (SAGE) and Massively Parallel Signature Sequencing (MPSS) are some of the latest techniques to learn more about functional genomics. The future of tree genomics is bright, but only serious investigations can help to accelerate the systems breeding that integrates information on gene function ensuring superior genotypes.