THE GENETIC IMPROVEMENT OF CULTIVATED SOYBEAN (GLYCNE MAX) IS HINDERED BY A LOW LEVEL OF GENETIC DIVERSITY, PRIMARILY DUE TO THE DOMESTICATION BOTTLENECK, WHICH ACCOUNTS FOR A ~50% REDUCTION IN DIVERSITY AND A ~80% LOSS OF RARE ALLELES PRESENT IN WILD SOYBEAN (GLYCINE SOJA) - THE PROGENITOR OF CULTIVATED SOYBEAN. TO FACILITATE THE UTILIZATION OF THE UNTAPPED GENETIC VARIATION IN THE WILD ANCESTORS FOR SOYBEAN ENHANCEMENT, IT IS ESSENTIAL TO UNDERSTAND THE GENETIC AND MOLECULAR BASES UNDERLYING THE SUITE OF DOMESTICATION-RELATED TRAITS (DRTS) THAT DISTINGUISH THE CROP FROM THE WILD PROGENITOR. WHILE A NUMBER OF GENES AND CAUSAL MUTATIONS FOR DOMESTICATION TRANSITIONS OF A FEW 'QUALITATIVE' DRTS HAVE BEEN IDENTIFIED, MANY DRTS MODULATED BY MULTIPLE QUANTITATIVE TRAIT LOCI (QTLS), OR THOSE UNDER EPISTATIC INTERACTIONS REMAIN CHALLENGING. MOLECULAR DISSECTION OF SUCH TRAITS IS NOT ONLY IMPORTANT FOR BASIC UNDERSTANDING OF PLANT GROWTH AND DEVELOPMENT FORMING VARIOUS MORPHOLOGICAL AND PHYSIOLOGICAL TRAITS OF AGRONOMIC IMPORTANCE, BUT ALSO ESSENTIAL FOR DISCOVERY AND USE OF THE 'NEGLECTED TREASURES IN THE WILD' FOR ENHANCEMENT OF ELITE CULTIVARS. THROUGH A DECADE OF EFFORTS, THE PD AND COLLABORATORS HAVE DEVELOPED TWO LARGE RECOMBINANT INBRED LINE (RIL) POPULATIONS COMPOSED OF >3,000 INDIVIDUAL LINES DERIVED FROM TWO CROSSES BETWEEN A SOYBEAN CULTIVAR WILLIAMS 82 AND EACH OF TWO WILD SOYBEAN ACCESSIONS, ONE OF WHICH CARRIES TWO QTLS CONFERRING TOLERANCE TO SOYBEAN CYST NEMATODE. THESE RILS HAVE BEEN DEMONSTRATED TO BE VERY POWERFUL FOR GENETIC DISSECTION OF THE COMPLEX DRTS. MORE RECENTLY, THE PDAND CO-WORKERS HAVE FINE-MAPPED A CLUSTER OF QTLS UNDERLYING MULTIPLE DRTS INCLUDING LEAFLET SIZE, MAIN STEM LENGTH, PUBESCENCE FORM, PLANT VININESS, AND STEM TWISTING GROWTH, AND DELIMITED THE CLUSTER INTO A ~29-KB GENOMIC REGION, WHICH ONLY HARBORS TWO DUPLICATED LONG NON-CODING RNA (LNCRNA) GENES.THE CENTRAL GOAL OF THIS PROJECT IS TO DECIPHER THE MOLECULAR MECHANISMS BY WHICH THE LNCRNA GENES REGULATE THE MULTIPLE MORPHOLOGICAL DRTS TOWARDS EFFECTIVE MODIFICATION OF DRT-RELATED TRAITS.WE ANTICIPATE THAT THE PROPOSED WORK WILL PROVIDE NOVEL INSIGHTS INTO THE MECHANISMS OF PLEIOTROPY AND 'DOMESTICATION SYNDROME', EXEMPLIFY THE EVOLUTIONARY INNOVATION AND CONSEQUENCE OF GENE DUPLICATION, AND PAVE NEW STRATEGIES FOR EXPLOITATION OF WILD SOYBEAN GERMPLASM TOWARDS SUSTAINABLE IMPROVEMENT OF SOYBEAN CULTIVARS FOR HIGH YIELD POTENTIAL AND ENHANCED ENVIRONMENTAL RESILIENCE.?

Purdue University, West Lafayette IN

Investigators