INTEGRATING MOLECULAR AND BIOCHEMICAL APPROACHES FOR JACKFRUIT (ARTOCARPUS HETEROPHYLLUS LAM.) GERMPLASM CHARACTERIZATION: A REVIEW

Abstract

Artocarpus heterophyllus Lam. (jackfruit) is an important tropical fruit species due to its nutritional value, economic value, and ecological importance. Due to its widespread presence throughout South and Southeast Asia, it is, however, less utilized genetically than many other major tropical fruit species. While several independent studies have examined both the molecular diversity and biochemical characteristics of the germplasm of jackfruit, there has not yet been an inclusive integration of these two methodologies. The purpose of this review is to evaluate the progression of molecular characterization starting with random amplified polymorphic DNA (RAPD) and inter-simple sequence repeat (ISSR) markers followed by simple sequence repeats (SSRs) and then genome-wide single nucleotide polymorphism (SNP) discoveries as well as recent chromosome-scale genome assembly. In addition to evaluating the advancements in molecular characterization, this review also evaluates the progress in biochemical characterization which includes nutritional composition, phytochemical/antioxidant diversity, seed protein/isozyme variation, starch properties/lipid composition and volatile aroma profiles. Rather than treat each area of research independently, this review analyzed how molecular data can be used to complement biochemical data, identified discrepancies among studies and highlighted the methodological limitations that have prohibited direct comparison of the germplasm collections. The available evidence demonstrated significant genetic and biochemical variability within jackfruit that is significantly associated with geographic location, but demonstrated that multi-disciplinary analysis of germplasm panels are still relatively rare. Recent developments in genomic resources offer an unprecedented opportunity to link these disciplines at a high-resolution using genetics with comprehensive datasets of phenotype and biochemistry. Future work would include population scale SNP genotyping, marker-trait associations, untargeted metabolomics and establishment of a well-characterized core collection of germplasm representing the genetic diversity of the species, moving beyond the current focus on Indian accessions.