Selection and General Combining Ability Evaluation of the Sweet Corn Inbred Lines

This study was to perform selection and assessment of general combining ability of the sweet corn inbred lines to select the combination of yield and quality to serve the production of high-yield and quality sweet maize varieties for Vietnam market. The genetic diversity of 32 S4-S6 self-combining sweet corn lines originating from China, USA, Thailand, Philippines, Taiwan was assessed based on the phenotype in Spring 2018 conditions using NTSYS software and identified 31 groups/32 lines at the difference of 29%. Selection of elite lines was made based on the Oclit distance biological statistics program with phenotypic traits selected 8 lines (D6, D7, D15, D21, D26, D28, D31, D32). These sweet maize lines have had a short to medium day growing time (104-111 days), average tree height (94.75-134.88cm), individual productivity reaches from 15.91 to 23.03 grams, Brix degree reached over 13%. These eight lines were introduced to the top cross with two tested corn plants in the Winter of 2018 and determined the combined ability (GCA) of 8 lines based on 16 hybrid combinations using genetic software. In the Spring crop of 2019, two lines D26 and D31 were identified that have had the high combined ability for productivity and quality for breeding, high-yield and quality sweet corn varieties.