벼 種間交雜 O. sativa L.×O. grandiglumis Prod.에서 戾交雜과 胚珠培養의 效率性

Efficiency of backcrossing and ovule culture in an interspecific cross between O. sativa L. and O. grandiglumis Prod.

For the successful production of F₁ plants and backcrossed progenies, various factors concerning seed-setting and plant recovery from ovules were evaluated in the interspecific cross between Hwaseongbyeo (AA) and O. grandiglumis (CCDD). Ovule culture time was quite critical for plant regeneration from cultured ovules with its highest rate at 15 days after pollination. Plants were not recovered from ovules less than 7 days or more than 21 days after pollination. Hormones applied to plants during booting stage significantly affected seed-setting and plant regeneration. For the seed-setting, GA₃ was most effective with single or combined treatments. 2, 4-D proved quite effective for plant regeneration, showing 80% regeneration rate in 2, 4-D 110ppm treatment and 85% in combined treatment, 2, 4-D 110ppm+NAA 50ppm+Kinetin 75ppm. When F₁ was used as female parent for backcross, seed-setting was quite low due to the severe shattering and abnormal embryo development. Non-clipping and successive pollination method was proved quite effective in preventing of shattering, resulting in elevated seed-setting and plant regeneration compared with the conventional clipping method. Embryo development was increased by successive backcross, reaching the highest rate of 6.3% at BC₃F₁ generation. The same trend was observed for plant regeneration rate, 2, 4% at BC₂F₁ and 100% at BC₃F₁ generation.