Effects of genes increasing the number of spikelets per panicle, TAW1 and APO1, on yield and yield-related traits in rice

Figures & data

Table 1. Temperature and sunshine duration in this study and major Koshihikari-cultivated regions.

City, prefecture	Year	Heading date	Temperature (°C)			Sunshine duration (hour)
			60-31 DBH	30-1 DBH	1-30 DAH	60-31 DBH	30-1 DBH	1-30 DAH
Daisen, Akita	Average	10-Aug	20.3	23.6	23.3	5.0	5.6	5.7
	2015	09-Aug	20.7	25.3	22.6	6.9	6.0	3.6
	2016	11-Aug	21.0	24.8	24.9	4.3	7.1	7.0
Tukuba, Ibaraki	Average	03-Aug	20.5	24.2	25.4	3.9	4.7	5.7
Takada, Niigata	Average	07-Aug	21.4	25.4	25.9	4.4	5.5	6.0

Notes: Data publicized by Japan Meteorological Agency were used. Average: Average from 1981 to 2010, DBH: Days before heading, DAH: Days after heading.

Table 2. Morphological differences in the panicle, stem, and leaf between the rice variety Koshihikari and three NILs.

Varietiy and lines	The number of differentiated spiklelets (per panicle)	The number of degenrated spiklelets (per panicle)	The number of spiklelets (per panicle)	The number of primary rachis branches (per panicle)	The number of primary spiklelets (per panicle)	The number of secondary spiklelets (per panicle)	Length of culm (cm)	Diameter of internode (mm)	Length of leaf blade (cm)	Width of leaf blade (cm)	Length of leaf sheath (cm)
Koshihikari	98	11	88	8.7	49	39	89	2.93	36.3	.95	24.3
NIL-taw1	155**	42**	113^**	8.5NS	43**	70**	81**	2.99NS	35.3NS	.93NS	24.2NS
NIL-apo1-D3	198**	43**	155**	13.1**	45NS	110**	93NS	3.51**	35.7NS	1.12**	25.1NS
NIL-apo1-D4	162*	31**	131*	9.9NS	50NS	82*	101**	3.29*	38.8*	1.00*	26.0**

Notes: Significance: *p < .05; **p < .01; NS, not significant (Paired t-test compared with Koshihikari, N = 6 (2 years × 3 replications)).

Table 3. Morphological differences in the spikelets and brown rice grain between the rice variety Koshihikari and three NILs.

Varietiy and lines	Spikelet		Brown rice grain
	Length (mm)	Width (mm)	Length (mm)	Width (mm)	Thickness (mm)
Koshihikari	6.40	3.47	5.09	3.00	2.17
NIL-taw1	6.25**	3.39NS	4.94*	2.93NS	2.06**
NIL-apo1-D3	6.32**	3.48NS	5.07NS	2.99NS	2.15NS
NIL-apo1-D4	6.25**	3.32*	4.99*	2.89*	2.09*

Notes: Significance: *p < .05; **p < .01; NS, not significant (Paired t-test compared with Koshihikari, N = 6 (2 years × 3 replications)).

Table 4. Differences in yield and yield-related-traits, including yield components, between the rice variety Koshihikari and three NILs.

Varietiy and lines	Heading date	Degree of lodging		Gross brown rice yield (gm^−2)	Immature brown rice weight (gm^−2)	Yield (Brown rice yield)			PN (m^−2)	SN (per panicle)	TSN (m^−2)	TGW (g)	RP (%)	Unhulled rice weight (gm^−2)	Straw weight (gm^−2)	Total dry weight (gm^−2)
		2015	2016			2015	2016	average
		(.0–5.0)				(gm^−2)	(gm^−2)	(gm^−2)
Koshihikari	10-Aug	4.0	1.3	665	17	625	671	648	404	75	29947	23.8	91.0	797	834	1631
NIL-taw1	10-Aug	4.0	2.7	665NS	59 **	582	630	606 *	414 NS	101 **	41009 **	20.7 **	71.4 **	833 *	738 **	1572 *
NIL-apo1-D3	11-Aug	4.7	4.0	644 NS	38 **	547	664	606 NS	353 **	104 **	36545 **	22.9 **	72.2 **	802 NS	724 *	1527 NS
NIL-apo1-D4	11-Aug	5.0	4.5	598 **	46 **	522	582	552 **	364 *	105 **	37647 **	21.1 **	69.5 **	754 *	826 NS	1580 NS

Notes: PN: the number of panicles per area, SN: the number of spikelets per panicle, TSN: the number of spiklets per area, TGW: thousand grain weight, RP: the percentage of ripened grain (RP). Significance: *p < .05; **p < .01; NS, not significant (Paired t-test compared with Koshihikari, N = 6 (2 years × 3 replications)).