보리 出穗期의 臨界日長의 究明과 日長變動에 따른 組合能力에 관한 硏究

Studies on the Critical Daylength for Heading of Barley, and its General and Specific Combining Ability under Different Daylength Conditions

4×4 barley diallel set of cross was tested to study the heading responses under 9-, 11-, 13-, 15-, and 24-hours day conditions and under critical turning point, and to obtain the information for earliness of crossing materials on basis of general and specific combining ability. Critical turning point for heading was expressed under long day condition in. Suweon 4, Suweon 18 and their F₁-hybrids with late heading, while it was showed under short day condition in Haganemugi(11.35 hour). However, critical turning point of F₁-hybrids of Haganemugi was under long day-length condition. Barsoy had the intermediate critical turning point for heading, and its F₁-hybrids revealed shorter critical turning point rather than their parents. All parents and F₁-hybrids headed earlier under long day conditions than under short day conditions. Among the parents the earliest heading was obtained from Haganemugi followed by Barsoy, Suweon 4 and Suweon 18 under all day-length conditions except critical turning point. Positive correlations were obtained between days to heading of parents and of F₁-hybrids, especially appearing the higher correlations under short day conditions. This indicates that mid-parent value gives good predictions of F₁-hybrid values for headings. General combining ability is much more important than specific combining ability for headings, which is mostly controlled by the additive gene action under all day-length conditions including critical turning point. Suweon 4 and Suweon 18 were poor combiners, while Haganemugi and Barsoy were good combiners under all day-length conditions except Haganemugi was expressed as a poor combiner under critical turning point for earliness. For the development of early varieties in heading it is not only necessary to assemble the early genes into particular progenies by early heading varieties with great effect of GCA, but also it is important to diversify the constitution of early genes by crossing between different varieties with extensive genetic background for earliness.