Inheritance study for lint colour in naturally brown coloured upland cotton (Gossypium hirsutum L.)

Abstract

The naturally coloured cotton is the age old crop holding evidence in ancient civilization. Over the course of time, the machine spinnable superior white linted varieties replaced the cultivation of coloured cotton which having poor yield and fibre quality. In the present era, concerns about pollution and toxicity caused by synthetic dyes and dyeing industries have resurrected the interest of naturally coloured cotton. In view of eco-friendly processing, improving the fibre characteristics of naturally coloured cotton is the need of the hour. The study of genetics behind the colour development serve in developing coloured linted varieties with enhanced fibre quality by crossing with superior white linted lines. The present study involved studying F2 populations of direct and reciprocal crosses between two naturally coloured (Parbani American and Red 5–7) and one white fibred (MCU 5) upland cotton. The F1 was intermediate to parents in fibre colour. The phenotypic ratio in F2 was observed to be 1:2:1 proving the inheritance to be governed by single incompletely dominant gene. But a lot of variation for colour intensity in F2 could be related to more than one loci or the presence of modifiers. This could be further examined at molecular level in future.