Table 1. Plant morphological characters in the selected early flowering lines and their four parental cultivars.

Line	Plant height (cm)	Spike length (cm)	No. spikelets per spike	No. grains per spike	No. grains per spikelet	Selfed seed fertility (%)	Thousand-grain weight (g)	Liter-grain weight (g)	Days to heading
Yukichikara	54 ± 1.9	7.2 ± 0	15.7 ± 0.3	39.3 ± 1.2	2.5 ± 0	93.6 ± 0.1	33.9 ± 0.3	679 ± 8.9	181
SB3#3	49 ± 1.7	7.6 ± 0.3	15.7 ± 0.3	35.0 ± 1.7	2.2 ± 0.1	89.3 ± 2.2	35.4 ± 0.5*	650 ± 7.1**	178
SB11-1#3	56 ± 1.9	7.3 ± 0.2	16.0 ± 0	37.3 ± 0.9	2.3 ± 0.1	92.7 ± 2.1	37.0 ± 0.3**	663 ± 4.5	178
SB11-2#3	54 ± 1.1	8.9 ± 0.2**	16.0 ± 0	37.7 ± 1.3	2.4 ± 0.1	90.6 ± 1.8	35.7 ± 0.1**	679 ± 3.4	179
Kitanokaori	50 ± 0.6	8.5 ± 0.4	23.3 ± 0.7	55.3 ± 5.0	2.4 ± 0.2	88.4 ± 2.3	36.5 ± 0.4	694 ± 4.0	195
SB9#2	53 ± 1.6	9.7 ± 0.2	22.7 ± 0.3	54.3 ± 0.3	2.4 ± 0	92.6 ± 2.1	41.1 ± 0.9**	673 ± 7.5	192
SB16-1#1	51 ± 0.7	11.0 ± 0.5	22.0 ± 0*	49.7 ± 1.8	2.3 ± 0.1	92.4 ± 2.7	38.8 ± 0.4*	682 ± 6.3	188
SB16-1#2	55 ± 0.7*	7.2 ± 3.0	21.7 ± 0.3*	45.7 ± 2.0*	2.1 ± 0.1	85.4 ± 1.9	46.1 ± 1.1**	665 ± 13	189
Haruyokoi	65 ± 1.2	8.4 ± 0.1	17.0 ± 0.6	35.0 ± 0.6	2.1 ± 0.1	82.4 ± 1.1	39.9 ± 0.3	707 ± 4.6	195
SB12#1	63 ± 1.3	8.6 ± 0.3	15.3 ± 0.3*	34.7 ± 0.7	2.3 ± 0	91.3 ± 1.0*	45.3 ± 0.5**	695 ± 7.8	188
SB13-2#1	70 ± 3.5	10.1 ± 0.5**	17.3 ± 0.7	39.3 ± 3.5	2.3 ± 0.1	89.2 ± 2.9*	41.4 ± 0.3*	675 ± 13**	189
Haruhinode	56 ± 2.9	8.1 ± 0.2	16.7 ± 0.7	34.0 ± 1.5	2.0 ± 0.1	86.1 ± 2.3	37.6 ± 0.4	721 ± 3.6	196
SB14#3	58 ± 0.8	8.0 ± 0.5	16.3 ± 0.3	28.0 ± 1.5	1.7 ± 0.1	80.6 ± 1.3	48.0 ± 0.5**	680 ± 4.1**	191

Significant differences between each selected early flowering line and its parental cultivar were indicated by asterisks (*P < 0.05; **P < 0.01).