Inheritance of time of flowering in upland cotton under natural conditions

Abstract

Abstract Time to flowering is an essential component of the adaptation and productivity of cotton ( Gossipium hirsutum ) in various agro‐ecological zones. This article presents a study of the genetic control of this trait in two crosses obtained from different early‐maturity parental lines. In each cross, multiple generations including P 1 , F 1 , P 2 , B 1 , B 2 and F 2 were evaluated under two natural field conditions in 2004 and 2005. The data on time to flowering in the F 2 populations had a continuous distribution but deviated from normality. A joint segregation analysis (JSA) revealed that time of flowering in upland cotton was controlled by a mixture of an additive major gene and additive‐dominant polygenes. The first‐ and second‐order genetic parameters were all calculated based on the mixture of major gene and polygene inheritance models using JSA. These results suggested that there was considerable genetic diversity and complexity in days to anthesis in upland cotton. This variation can be used to formulate the most efficient breeding strategy and to design cotton for a particular environment.