Molecular marker - a new approach for forest tree improvement

Abstract

Molecular markers are important tools for forest tree improvement. Forest tree improvement has therefore been a slow and arduous process by virtue of the large size and long generation times of trees. The most important markers are hybridization based D A markers RFLP and, PCR based DNA markers such as Randomly Amplified Polymorphic DNAs (RAPDs), Simple Sequence Repeats (SSRs) or Microsatellites/ Sequence Tagged Sites (STS), Amplified Fragment Length Polymorphisms (AFLPs), Inter-Simple Sequence Repeats (ISSR) and Cleaved Amplified Polymorphic Sequences (CAPS). Recent advances in molecular biology offer considerable scope to understand and evaluate population structure, levels of genetic variation, and relatedness and mating systems of tropical tree species. Various molecular techniques are being investigated for a quick and reliable assessment of genetic diversity and related parameters for a number of timber and non-timber tree species in the country. Their application is very important in case of estimating polymorphism and relatedness, genotype characterization and marker-assisted selection. Isozymes generally provides ample information and are inexpensive, rapid, and technically easy to apply . The large sized, longregeneration cycle and sporadic seed production of trees cause numerous problems in tree improvement programs. However, the molecular markers simply reduce the rotation period to attaining a merchantable size, so it can be sold in a shorter period of time with a disease resistance, pest resistance, and phenotypicaly and genotypicaly good tree species which satisfied the national needs of the country