Comparative analysis of BLUP and GCA for parental selection in marigold (Tagetes erecta L.) for hybrid development

The area under marigold cultivation is increasing over the years and so is the demand for marigold seeds. To meet the increasing demand, hybrid varieties are preferred as they produce higher yields, for which the right parental selection is of major concern. Male sterility being the prerequisite for economical hybrid seed production of marigold, we have attempted to strategize the selection of male sterile seed parent and fertile pollen parent for yield and yield-related traits. The study was undertaken across multiple forms of male sterile lines morphologically varying in apetaloid and petaloid types, therefore use of BLUP and GCA was evaluated as a criterion to select the parents for the hybridization program. Results suggested apetaloid male sterile lines as better seed parents for days to bud initiation, while, petaloid male sterile lines can be selected for the improvement of shelf life and flower diameter. Results from BLUP and GCA were in agreement with each other for the traits studied. However, BLUP-based comparison of different lines is less tedious as it eliminates the laborious procedure of developing multiple hybrids and evaluating them to study the combining ability effects.