Combining ability of carrot (Daucus carota L.) lines and heritability of yield and its quality components

Abstract

The purpose of this research was to investigate the combining ability of inbred lines in terms of traits important for the development of hybrid carrot cultivars with high yields and better root quality. The experimental plant material consisted of 15 inbred lines that were crossed in an incomplete diallel design to produce 34 hybrids. It was observed that the variation of general combining ability (GCA), specific combining ability (SCA) and reciprocal effects (RE) were significant for all of the tested characters, except SCA for sugars. Among the tested lines, the RFO had the most positive GCA for the yield; at the some time, the RFO line had negative GCA for carotenes and dry matter content. A significant positive GCA was found for all traits, except monosaccharides and nitrates, for the 2163 line. Most of the crosses based on the RFO and 2163 lines yielded well; additionally, the hybrids based on 2163 presented high levels of quality characters. The ratio of GCA:SCA indicated that the quality traits were mainly affected by additive gene effects, but the yield was controlled more by non-additive gene effects. Heritability in a broad sense presented a higher environmental influence for yield than the quality characters of carrot roots.

Dissecting the Genetic Architecture of Shoot Growth in Carrot (Daucus carotaL.) Using a Diallel Mating Design

“…Consequently, hybrid vigor was evident for root biomass, which had relatively high proportions of nonadditive genetic variation, significant estimates of an inbred penalty, and signals of pseudo-overdominance ( Figure 8 and Figures S47 and S53 in File S1 ). This result coincides with widespread evidence of heterosis in plants, whereby hybrids demonstrate increased developmental speed and greater biomass acquisition relative to their inbred parents ( Shull 1908 ; East 1936 ; Birchler et al 2003 ; Meyer et al 2004 ), and agrees with previous observations of hybrid vigor for root weight in carrot ( Simon et al 1982 ; Duan et al 1996 ; Simon and Strandberg 1998 ; Suh et al 1999 ; Jagosz 2011 , 2012 ).…”

“…Many carrot breeding programs employ the inbred-hybrid method, which is enabled by the widespread availability of cytoplasmic male sterility (CMS) in carrot germplasm ( Peterson and Simon 1986 ; Simon 2000 ). Accordingly, heterosis is considered a promising mechanism to increase yield in carrot ( Rubatzky et al 1999 ), and hybrid vigor has been documented for important traits such as carrot root yield ( Duan et al 1996 ; Suh et al 1999 ; Simon and Strandberg 1998 ; Jagosz 2011 , 2012 ; Simon et al 1982 ), carotenoid content ( Santos and Simon 2006 ), and resistance to Alternaria leaf blight ( Simon and Strandberg 1998 ). However, the development and adoption of heterotic groups in carrot remains limited, and has not been described in detail.…”

Mining for Candidate Genes Controlling Secondary Growth of the Carrot Storage Root

“…The impact of environmental factors, e.g., planting density [ 2 ], water regime [ 3 ], soil forming [ 4 ], temperature [ 5 ], and nutrient availability [ 6 ] on carrot root growth have been described. It was also reported that heterosis resulted in increased carrot storage root biomass and improved its quality [ 7 ] and a strong linear relationship between shoot and root biomass was shown [ 8 ].…”

Capacidade de combinação de genitores de cenoura para caracteres de produtividade de raízes e tolerância à queima-das-folhas

“…Poucos trabalhos publicados na literatura apresentam estimativas da capacidade combinatória em cenoura. No entanto, alguns estudos mostraram a existência de heterose e a eficiência da utilização de análise dialélica, para a escolha de genitores e de combinações híbridas superiores (Duan et al, 1996;Simon & Strandberg, 1998;Guan et al, 2001;Jagosz, 2012;Carvalho et al, 2014).…”