Inheritance of Lint Colour in Cocanadas Cotton

1. The inheritance of lint colour in Cocanadas cotton was studied. The white linted Gocanada pure line ‘45’ was a simple recessive to Khaki A9 (Lc₁^K). Strain Cocanadas-1 carried the very light brown gene Lc₂^v while the behaviour of the deeper coloured pure lines ‘ 123 ‘ and ‘129’ suggested their probable genotypes as Lc₂^B. Nanking Khaki behaved as a simple dominant over Cocanadas-1 (Lc^V₂) indicating that it carried a darker allele at the same locus while the parental and F₁ grading would admit of an Lc₂^K postulate. G 1037 and G 1019 exhibited a bifactorial difference with Coconadas-1 confirming their genotype to be Lc₁^K.

2. The effect of environment on the colour expression and fading on exposure especially on the light brown low potency gene were considered to be the probable causes for high colour variability in Lc₂^V.

3. A study of the association between staple length and lint colour revealed a uniform reduction in the length of brown segregates in all the hybrid progenies.

4. The importance of the genic status of the Cocanada area was indicated.