Genetics of awnness in the F2 population of basmati crosses of rice

Abstract

The present investigation was conducted to study the gene action of awn character in rice. Hybridization was done between four female parents’ viz., ASD 16, ADT 37, MDU 6 and TKM 13 with one male parent viz., Improved Pusa Basmati 1. All the female parents are awnless, but the male parent is awned. F1 of all the crosses except ADT 37 × Improved Pusa Basmati 1 exhibited awns. This result indicated that awn character was controlled by dominant gene in those three crosses. In the F1 of the ADT 37 × Improved Pusa Basmati 1, awn expression was suppressed which indicated that suppressor or inhibitor gene may be present in ADT 37. All the F1s were selfed and F2 generation was obtained. F2 population of all the four crosses viz., ASD 16 × Improved Pusa Basmati 1, ADT 37 × Improved Pusa Basmati 1, MDU 6 × Improved Pusa Basmati 1 and TKM 13 × Improved Pusa Basmati 1 were studied to know the inheritance pattern of awnness. Based on chi-square test it was found that inheritance pattern of awnness fit in the ratio of 9:7 (awned: awnless) in the F2 generation of three crosses viz., ASD 16 × Improved Pusa Basmati 1, MDU 6 × Improved Pusa Basmati 1 and TKM 13 × Improved Pusa Basmati 1 and the awn character appeared to be governed by complementary gene action. In the cross, ADT 37 × Improved Pusa Basmati 1 showed a ratio of 7:9 (awned: awnless). The reason for the differences in gene action may be attributed to the presence of two different sets of genes in female parents of the crosses.

Keywords

• Awn
• complementary gene action
• dominant gene
• rice.