Heterosis, combining ability on yield, yield components and quality traits of purple sweet corn

【Objective】Heterosis and combining ability analysis on yield，yield components and quality traits of 20 purple sweet corn inbred lines and 2 tested varieties were conducted，to provide material foundation and theoretical basis for effectively creating high-yield sweet corn inbred lines.【Method】Twenty purple sweet corn inbred lines（TD01-TD20） and 2 tested varieties［yellow sweet corn inbred line（T1）and white sweet corn inbred line（T2）］were crossbred to obtain 40 hybrid combinations（TH01-TH40）that were taken as materials in a field experiment with randomized complete block design，in which SW1011 and Fancy 111 were taken two check varieties.Yield，yield components and quality traits of parental and hybrid combinations were determined. Mid-parent heterosis（Hm），heterobeltiosis（Hb），and general combining ability（GCA）analyses were conducted via Line×Tester model in AGD-R software.【Result】The purple color in seed coat was proven inherited from the male parent，and thus，dominated in all hybrids. Hm and Hb were observed in all investigated traits. Negative Hm，Hb，and GCA values on fresh ear harvesting time were observed in most parental lines， indicating such parental lines had potential for production of early harvest hybrids. Dominance effects were found in almost all the traits investigated，except for harvesting time and ear diameter，exemplifying the importance of non-additive genetic effects. Lines with high GCA value were TH05（T1×TD05），TH31（T2×TD11），TH20（T1×TD20），TH33（T2×TD13），TH34（T2×TD14），TH16（T1×TD16），TH08（T1×TD08），and TH25（T2×TD05）.【Conclusion】When purple sweet corn was crossbred with yellow sweet corn inbred lines or white sweet corn inbred lines，purple traits have dominance effects. Therefore，8 high-quality hybrid varieties and their parental lines are screened，which can be taken as parental materials for purple sweet corn variety cultivation in Vietnam.