Inheritance Pattern of Aroma in some Rice Cultivars

The inheritance of aroma was studied in twelve crosses, involving Madhuri-11, Pusa Basmati-1, Chinnor, Dubraj, Jawaphool, Ganga Baru, Laxmi Bhog Krishna Bhog, Lakhan Bhog, Kapoor Kranti, Thrun Bhog and Tulsi Amrit as aromatic parents and Surekha, Danteshwari, IR 64, Super rice-12 (IR 71703-221-1-5-2) and Super rice-5 (IR 71677-402-3-3-2) as non-aromatic parents. Out of twelve crosses two crosses viz; Surekha x Madhuri-11 and Danteshwari x Pusa Basmati-1 were found segregating in 7 aromatic: 9 non-aromatic ratios in F₂ whereas, F₁ was found non aromatic, suggesting two recessive genes responsible for aroma with complementary gene action. In contrast two other crosses viz; IR 64 x Dubraj and Super rice 12 x Ganga Baru were found segregating in 9 aromatic: 7 non aromatic ratio in F₂ whereas, F₁ was aromatic, suggesting the dominant alleles of two genes with complementary gene action responsible for aroma. In four crosses viz; IR 64 x Jawaphool, Super rice-12 x Lakhan Bhog, Super rice-12 x Kapoor Kranti and Super rice-12 x Thrun Bhog, F₁ were found aromatic and F₂ showed 3 aromatic: 1 non-aromatic ratio. It showed single dominant gene controlling aroma whereas, in three crosses viz; Super rice 12 x Laxmi Bhog, Super rice 12 x Krishna Bhog and Super rice 5 x Tulsi Amrit it was found that F₁ was aromatic and F₂ generation showed 15 aromatic: 1 non-aromatic ratio due to duplicate gene action of two dominant genes for aroma. In cross IR 64 x Chinnor F₁ was aromatic but F₂ generation indicated 13 aromatic: 3 non-aromatic ratio. It suggested that inhibitory gene action is responsible for aroma in aromatic parents. The present inheritance study gives good opportunity to transfer aromatic genes to the non aromatic high yielding, good agronomic base cultivars.