Growth and Photosynthesis Responses of a Super Dwarf Rice Genotype to Shade and Nitrogen Supply

doi:10.1016/j.rsci.2021.01.007

Abstract

Abstract:

Specific aspects of plant cultivation require tests under fully controlled environmental conditions with restricted energy supply, such as orbit-based space laboratories and low-light conditions. For these growing conditions, super dwarf plants have been developed as model crops, and a gibberellin- deficient Super Dwarf Rice genotype was proposed as a model crop for space flight plant experiments. We tested this genotype in a climate chamber experiment under different illumination and nitrogen supply levels to assess its suitability under scenarios with limited resource availability. A 25% reduction in illumination led to a 75% reduction in yield, mainly due to a 60% reduction in formed tillers and 20% reduction in grain weight, and a 80% reduction in illumination caused total yield loss. Leaf area under reduced illumination was significantly lower, and only marginal changes in the dimensions of leaves were observed. Plant photosynthesis was not significantly different between control and 75% illumination. This was explained by a higher photochemical efficiency under lower light conditions and a reduced mesophyll resistance. Therefore, we concluded that this genotype is well-suited for plant experiments under space and light-limited conditions since it kept its small stature and showed no shade avoidance mechanisms, such as leaf elongation, which would complicate experiments under low-light conditions. Nitrogen concentrations of 2.8 and 1.4 mmol/L led to no differences in plant growth. We concluded that a nitrogen concentration of 1.4 mmol/L is sufficient for this genotype under the light intensities.

Key words: super dwarf rice, photosynthetic limitation analysis, shade, nitrogen

Schmierer Marc, Knopf Oliver, Asch Folkard. Growth and Photosynthesis Responses of a Super Dwarf Rice Genotype to Shade and Nitrogen Supply[J]. Rice Science, 2021, 28(2): 178-190.

Figures/Tables 8

References 52

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Treatment		No. of tillers per plant	Percentage of productive tillers (%)		No. of grains per panicle	Percentage of spikelet fertility (%)	Average single grain weight (mg)	Grain yield per plant (g)
N (mmol/L)	Light (L)	No. of tillers per plant	Percentage of productive tillers (%)		No. of grains per panicle	Percentage of spikelet fertility (%)	Average single grain weight (mg)	Grain yield per plant (g)
2.8	Full light	24.0 ± 0.8 a	66 ± 40 a		13.2 ± 0.1 a	91 ± 2 a	21.0 ± 0.3 a	4.002 ± 0.323 a
	75% illumination	10.3 ± 1.1 b	64 ± 11 a		11.3 ± 1.3 ab	87 ± 0 a	16.4 ± 0.4 a	1.051 ± 0.155 b
	20% illumination	6.7 ± 1.9 b	3 ± 2 b		1.3 ± 1.1 c	8 ± 7 b	4.8 ± 3.9 b	0.005 ± 0.004 c
1.4	Full light	30.0 ± 1.3 a	54 ± 3 a		14.2 ± 0.9 a	87 ± 2 a	20.3 ± 0.1 a	3.980 ± 0.234 a
	75% illumination	10.3 ± 2.1 b	56 ± 7 a		12.6 ± 1.7 ab	78 ± 4 a	15.8 ± 0.6 a	0.799 ± 0.073 bc
	20% illumination	3.3 ± 1.2 b	6 ± 5 b		3.7 ± 3.0 bc	0 ± 0 b	0.0 ± 0.0 b	0.000 ± 0.000 c
F value	F_L	81.28***	38.91***		19.03***	248.78***	45.71***	185.14***
	F_N	0.37	0.95		0.79	4.40	1.60	0.27
	F_LN	3.45	0.53		0.08	0.17	0.70	0.20
Relative decrease compared to control (Full N and full light) (%)
2.8	75% illumination	-57	-3	-13		-4	-22	-74
2.8	20% illumination	-72	-95	-90		-91	-77	-100
1.4	Full light	25	-18	7		-5	-4	-1
	75% illumination	-57	-15	-5		-14	-25	-80
	20% illumination	-86	-92	-72		-100	-100	-100
Contribution to yield loss (%)
2.8	75% illumination	58	3	13		4	22
2.8	20% illumination	17	22	21		21	18
1.4	Full light	-42	31	-12		8	6
	75% illumination	49	13	4		12	21
	20% illumination	19	20	16		22	22

Treatment		No. of tillers per plant	Percentage of productive tillers (%)		No. of grains per panicle	Percentage of spikelet fertility (%)	Average single grain weight (mg)	Grain yield per plant (g)
N (mmol/L)	Light (L)	No. of tillers per plant	Percentage of productive tillers (%)		No. of grains per panicle	Percentage of spikelet fertility (%)	Average single grain weight (mg)	Grain yield per plant (g)
2.8	Full light	24.0 ± 0.8 a	66 ± 40 a		13.2 ± 0.1 a	91 ± 2 a	21.0 ± 0.3 a	4.002 ± 0.323 a
	75% illumination	10.3 ± 1.1 b	64 ± 11 a		11.3 ± 1.3 ab	87 ± 0 a	16.4 ± 0.4 a	1.051 ± 0.155 b
	20% illumination	6.7 ± 1.9 b	3 ± 2 b		1.3 ± 1.1 c	8 ± 7 b	4.8 ± 3.9 b	0.005 ± 0.004 c
1.4	Full light	30.0 ± 1.3 a	54 ± 3 a		14.2 ± 0.9 a	87 ± 2 a	20.3 ± 0.1 a	3.980 ± 0.234 a
	75% illumination	10.3 ± 2.1 b	56 ± 7 a		12.6 ± 1.7 ab	78 ± 4 a	15.8 ± 0.6 a	0.799 ± 0.073 bc
	20% illumination	3.3 ± 1.2 b	6 ± 5 b		3.7 ± 3.0 bc	0 ± 0 b	0.0 ± 0.0 b	0.000 ± 0.000 c
F value	F_L	81.28***	38.91***		19.03***	248.78***	45.71***	185.14***
	F_N	0.37	0.95		0.79	4.40	1.60	0.27
	F_LN	3.45	0.53		0.08	0.17	0.70	0.20
Relative decrease compared to control (Full N and full light) (%)
2.8	75% illumination	-57	-3	-13		-4	-22	-74
2.8	20% illumination	-72	-95	-90		-91	-77	-100
1.4	Full light	25	-18	7		-5	-4	-1
	75% illumination	-57	-15	-5		-14	-25	-80
	20% illumination	-86	-92	-72		-100	-100	-100
Contribution to yield loss (%)
2.8	75% illumination	58	3	13		4	22
2.8	20% illumination	17	22	21		21	18
1.4	Full light	-42	31	-12		8	6
	75% illumination	49	13	4		12	21
	20% illumination	19	20	16		22	22

Developmental stage	Treatment		Leaf area (cm²)	SLA of whole plant (m²/kg)	Leaf area ratio (m²/kg)	Average leaf length (cm)	Average leaf width (cm)	Average leaf size (cm²)
Developmental stage	N (mmol/L)	Light (L)	Leaf area (cm²)	SLA of whole plant (m²/kg)	Leaf area ratio (m²/kg)	Average leaf length (cm)	Average leaf width (cm)	Average leaf size (cm²)
Heading	2.8	Full light	340 ± 30 a	276 ± 7 b	9.0 ± 0.2 b	7.62 ± 0.71 b	0.52 ± 0.01 a	3.9 ± 0.3 a
		75% illumination	219 ± 30 bc	308 ± 6 ab	11.3 ± 0.6 ab	8.04 ± 0.32 b	0.54 ± 0.04 a	4.4 ± 0.5 a
		20% illumination	138 ± 18 c	361 ± 26 ab	12.6 ± 0.4 a	10.20 ± 0.16 a	0.49 ± 0.01 a	5.0 ± 0.2 a
	1.4	Full light	338 ± 5 ab	267 ± 9 b	8.6 ± 0.8 b	7.72 ± 0.10 b	0.53 ± 0.01 a	4.1 ± 0.1 a
		75% illumination	218 ± 17 c	295 ± 3 ab	11.0 ± 0.5 ab	8.42 ± 0.14 ab	0.55 ± 0.02 a	4.7 ± 0.3 a
		20% illumination	132 ± 9 c	330 ± 13 ab	13.1 ± 0.3 a	8.28 ± 0.19 ab	0.50 ± 0.01 a	4.2 ± 0.0 a
	F value	F_L	33.48***	10.52**	19.52***	7.32**	1.91	1.88
		F_N	0.03	1.78	0.01	1.99	0.33	0.26
		F_LN	0.01	0.26	0.31	4.53	0.01	1.75
Flowering	2.8	Full light	395 ± 29 a	275 ± 6 b	5.7 ± 0.1 bc	7.60 ± 0.30 a	0.59 ± 0.02 a	4.5 ± 0.3 a
		75% illumination	143 ± 28 bc	259 ± 6 b	5.0 ± 0.8 c	9.08 ± 0.09 a	0.59 ± 0.02 a	5.3 ± 0.2 a
		20% illumination	117 ± 31 c	345 ± 4 a	10.2 ± 0.3 a	8.69 ± 0.49 a	0.53 ± 0.03 a	4.6 ± 0.5 a
	1.4	Full light	277 ± 13 ba	260 ± 0 b	5.2 ± 0.3 c	7.56 ± 0.16 a	0.61 ± 0.01 a	4.6 ± 0.1 a
		75% illumination	140 ± 21 c	311 ± 19 ab	6.6 ± 0.3 bc	8.69 ± 0.14 a	0.56 ± 0.04 a	4.9 ± 0.4 a
		20% illumination	100 ± 24 c	279 ± 14 b	7.8 ± 0.4 ab	8.54 ± 0.38 a	0.53 ± 0.02 a	4.5 ± 0.0 a
	F value	F_L	37.76***	5.62*	27.13***	7.15**	2.37	1.42
		F_N	3.99	1.04	1.14	0.43	0.00	0.26
		F_LN	2.45	10.99	7.47	0.11	0.21	0.25
Ripening	2.8	Full light	202 ± 6 a	246 ± 16 a	2.4 ± 0.2 ab	6.77 ± 0.21 ab	0.59 ± 0.00 a	4.0 ± 0.1 a
		75% illumination	53 ± 5 b	199 ± 17 a	1.8 ± 0.2 b	6.36 ± 0.56 ab	0.60 ± 0.03 a	3.8 ± 0.2 a
		20% illumination	73 ± 17 b	358 ± 60 a	5.7 ± 0.8 a	8.83 ± 0.43 a	0.58 ± 0.02 a	5.1 ± 0.3 a
	1.4	Full light	215 ± 22 a	235 ± 6 a	2.3 ± 0.2 ab	5.81 ± 0.07 ab	0.56 ± 0.01 a	3.3 ± 0.1 a
		75% illumination	64 ± 5 b	243 ± 10 a	2.2 ± 0.2 b	5.31 ± 0.22 b	0.50 ± 0.04 a	2.7 ± 0.3 a
		20% illumination	44 ± 15 b	211 ± 57 a	3.1 ± 1.1 ab	7.10 ± 1.03 ab	0.57 ± 0.04 a	4.1 ± 0.9 a
	F value	F_L	56.52***	0.36	6.45*	6.09*	0.35	3.89*
		F_N	0.01	0.29	1.74	5.66*	3.04	4.89*
		F_LN	1.04	1.39	2.49	0.22	1.13	0.06
Developmental stage	Treatment		Flag leaf area (cm²)	SLA of flag leaf (m²/kg)	Chlorophyll a (µg/cm²)	Chlorophyll b (µg/cm²)	Chlorophyll a/b
Developmental stage	N (mmol/L)	Light (L)	Flag leaf area (cm²)	SLA of flag leaf (m²/kg)	Chlorophyll a (µg/cm²)	Chlorophyll b (µg/cm²)	Chlorophyll a/b
Heading	2.8	Full light	8.8 ± 0.3 a	110 ± 1 bc	43.6 ± 1.8 a	17.1 ± 2.6 a	2.6 ± 0.2 a
		75% illumination	11.0 ± 1.5 a	127 ± 4 ab	42.5 ± 1.2 a	18.8 ± 1.6 a	2.3 ± 0.2 a
		20% illumination	9.0 ± 1.2 a	109 ± 3 c	37.9 ± 2.5 a	13.3 ± 1.1 a	2.9 ± 0.1 a
	1.4	Full light	8.7 ± 0.4 a	108 ± 2 c	41.7 ± 1.4 a	14.5 ± 1.7 a	2.9 ± 0.2 a
		75% illumination	9.7 ± 0.1 a	130 ± 4 a	39.2 ± 1.0 a	15.8 ± 1.0 a	2.5 ± 0.1 a
		20% illumination	10.9 ± 0.6 a	125 ± 2 abc	33.2 ± 2.3 a	11.3 ± 0.9 a	2.9 ± 0.0 a
	F value	F_L	1.31	14.77***	5.66*	3.82	3.71
		F_N	0.04	3.34	3.32	2.73	1.51
		F_LN	1.30	3.52	0.21	0.04	0.16
Flowering	2.8	Full light	8.8 ± 0.6 a	119 ± 2 a	44.2 ± 1.1 ab	17.7 ± 1.6 a	2.5 ± 0.2 a
		75% illumination	10.6 ± 0.5 a	128 ± 8 a	34.9 ± 4.4 ab	13.2 ± 2.6 a	2.7 ± 0.2 a
		20% illumination	9.7 ± 0.9 a	134 ± 4 a	27.1 ± 2.0 b	8.3 ± 1.1 a	3.4 ± 0.3 a
	1.4	Full light	8.4 ± 0.6 a	108 ± 2 a	45.1 ± 3.9 a	18.5 ± 2.7 a	2.5 ± 0.2 a
		75% illumination	11.5 ± 1.1 a	137 ± 9 a	32.2 ± 3.4 ab	10.1 ± 1.5 a	3.2 ± 0.2 a
		20% illumination	8.9 ± 0.9 a	132 ± 4 a	31.1 ± 2.4 ab	10.6 ± 1.0 a	2.9 ± 0.6 a
	F value	F_L	3.46	5.30*	8.96**	7.62**	4.11*
		F_N	0.01	0.05	0.06	0.00	0.02
		F_LN	0.44	1.04	0.39	0.72	2.12
Ripening	2.8	Full light	9.9 ± 0.6 a	116 ± 1 b	43.5 ± 0.9 a	16.2 ± 0.4 a	2.7 ± 0.0 a
		75% illumination	8.1 ± 0.4 ab	144 ± 4 a	36.6 ± 0.3 c	12.9 ± 0.6 a	2.9 ± 0.2 a
		20% illumination	10.2 ± 0.6 a	134 ± 4 ab	29.6 ± 0.9 d	9.0 ± 0.5 b	3.3 ± 0.1 a
	1.4	Full light	8.7 ± 0.6 ab	118 ± 5 b	41.2 ± 0.6 ab	15.3 ± 0.4 a	2.7 ± 0.0 a
		75% illumination	9.2 ± 0.4 ab	140 ± 7 ab	37.6 ± 0.8 bc	13.8 ± 0.7 a	2.7 ± 0.1 a
		20% illumination	6.9 ± 0.1 a	121 ± 3 ab	20.6 ± 0.9 e	7.8 ± 1.1 b	2.7 ± 0.3 a
	F value	F_L	1.00	10.36**	182.61***	43.53***	1.44
		F_N	5.79*	1.35	21.07***	0.38	1.76
		F_LN	7.65**	1.00	15.16***	1.00	1.02

Developmental stage	Treatment		Leaf area (cm²)	SLA of whole plant (m²/kg)	Leaf area ratio (m²/kg)	Average leaf length (cm)	Average leaf width (cm)	Average leaf size (cm²)
Developmental stage	N (mmol/L)	Light (L)	Leaf area (cm²)	SLA of whole plant (m²/kg)	Leaf area ratio (m²/kg)	Average leaf length (cm)	Average leaf width (cm)	Average leaf size (cm²)
Heading	2.8	Full light	340 ± 30 a	276 ± 7 b	9.0 ± 0.2 b	7.62 ± 0.71 b	0.52 ± 0.01 a	3.9 ± 0.3 a
		75% illumination	219 ± 30 bc	308 ± 6 ab	11.3 ± 0.6 ab	8.04 ± 0.32 b	0.54 ± 0.04 a	4.4 ± 0.5 a
		20% illumination	138 ± 18 c	361 ± 26 ab	12.6 ± 0.4 a	10.20 ± 0.16 a	0.49 ± 0.01 a	5.0 ± 0.2 a
	1.4	Full light	338 ± 5 ab	267 ± 9 b	8.6 ± 0.8 b	7.72 ± 0.10 b	0.53 ± 0.01 a	4.1 ± 0.1 a
		75% illumination	218 ± 17 c	295 ± 3 ab	11.0 ± 0.5 ab	8.42 ± 0.14 ab	0.55 ± 0.02 a	4.7 ± 0.3 a
		20% illumination	132 ± 9 c	330 ± 13 ab	13.1 ± 0.3 a	8.28 ± 0.19 ab	0.50 ± 0.01 a	4.2 ± 0.0 a
	F value	F_L	33.48***	10.52**	19.52***	7.32**	1.91	1.88
		F_N	0.03	1.78	0.01	1.99	0.33	0.26
		F_LN	0.01	0.26	0.31	4.53	0.01	1.75
Flowering	2.8	Full light	395 ± 29 a	275 ± 6 b	5.7 ± 0.1 bc	7.60 ± 0.30 a	0.59 ± 0.02 a	4.5 ± 0.3 a
		75% illumination	143 ± 28 bc	259 ± 6 b	5.0 ± 0.8 c	9.08 ± 0.09 a	0.59 ± 0.02 a	5.3 ± 0.2 a
		20% illumination	117 ± 31 c	345 ± 4 a	10.2 ± 0.3 a	8.69 ± 0.49 a	0.53 ± 0.03 a	4.6 ± 0.5 a
	1.4	Full light	277 ± 13 ba	260 ± 0 b	5.2 ± 0.3 c	7.56 ± 0.16 a	0.61 ± 0.01 a	4.6 ± 0.1 a
		75% illumination	140 ± 21 c	311 ± 19 ab	6.6 ± 0.3 bc	8.69 ± 0.14 a	0.56 ± 0.04 a	4.9 ± 0.4 a
		20% illumination	100 ± 24 c	279 ± 14 b	7.8 ± 0.4 ab	8.54 ± 0.38 a	0.53 ± 0.02 a	4.5 ± 0.0 a
	F value	F_L	37.76***	5.62*	27.13***	7.15**	2.37	1.42
		F_N	3.99	1.04	1.14	0.43	0.00	0.26
		F_LN	2.45	10.99	7.47	0.11	0.21	0.25
Ripening	2.8	Full light	202 ± 6 a	246 ± 16 a	2.4 ± 0.2 ab	6.77 ± 0.21 ab	0.59 ± 0.00 a	4.0 ± 0.1 a
		75% illumination	53 ± 5 b	199 ± 17 a	1.8 ± 0.2 b	6.36 ± 0.56 ab	0.60 ± 0.03 a	3.8 ± 0.2 a
		20% illumination	73 ± 17 b	358 ± 60 a	5.7 ± 0.8 a	8.83 ± 0.43 a	0.58 ± 0.02 a	5.1 ± 0.3 a
	1.4	Full light	215 ± 22 a	235 ± 6 a	2.3 ± 0.2 ab	5.81 ± 0.07 ab	0.56 ± 0.01 a	3.3 ± 0.1 a
		75% illumination	64 ± 5 b	243 ± 10 a	2.2 ± 0.2 b	5.31 ± 0.22 b	0.50 ± 0.04 a	2.7 ± 0.3 a
		20% illumination	44 ± 15 b	211 ± 57 a	3.1 ± 1.1 ab	7.10 ± 1.03 ab	0.57 ± 0.04 a	4.1 ± 0.9 a
	F value	F_L	56.52***	0.36	6.45*	6.09*	0.35	3.89*
		F_N	0.01	0.29	1.74	5.66*	3.04	4.89*
		F_LN	1.04	1.39	2.49	0.22	1.13	0.06
Developmental stage	Treatment		Flag leaf area (cm²)	SLA of flag leaf (m²/kg)	Chlorophyll a (µg/cm²)	Chlorophyll b (µg/cm²)	Chlorophyll a/b
Developmental stage	N (mmol/L)	Light (L)	Flag leaf area (cm²)	SLA of flag leaf (m²/kg)	Chlorophyll a (µg/cm²)	Chlorophyll b (µg/cm²)	Chlorophyll a/b
Heading	2.8	Full light	8.8 ± 0.3 a	110 ± 1 bc	43.6 ± 1.8 a	17.1 ± 2.6 a	2.6 ± 0.2 a
		75% illumination	11.0 ± 1.5 a	127 ± 4 ab	42.5 ± 1.2 a	18.8 ± 1.6 a	2.3 ± 0.2 a
		20% illumination	9.0 ± 1.2 a	109 ± 3 c	37.9 ± 2.5 a	13.3 ± 1.1 a	2.9 ± 0.1 a
	1.4	Full light	8.7 ± 0.4 a	108 ± 2 c	41.7 ± 1.4 a	14.5 ± 1.7 a	2.9 ± 0.2 a
		75% illumination	9.7 ± 0.1 a	130 ± 4 a	39.2 ± 1.0 a	15.8 ± 1.0 a	2.5 ± 0.1 a
		20% illumination	10.9 ± 0.6 a	125 ± 2 abc	33.2 ± 2.3 a	11.3 ± 0.9 a	2.9 ± 0.0 a
	F value	F_L	1.31	14.77***	5.66*	3.82	3.71
		F_N	0.04	3.34	3.32	2.73	1.51
		F_LN	1.30	3.52	0.21	0.04	0.16
Flowering	2.8	Full light	8.8 ± 0.6 a	119 ± 2 a	44.2 ± 1.1 ab	17.7 ± 1.6 a	2.5 ± 0.2 a
		75% illumination	10.6 ± 0.5 a	128 ± 8 a	34.9 ± 4.4 ab	13.2 ± 2.6 a	2.7 ± 0.2 a
		20% illumination	9.7 ± 0.9 a	134 ± 4 a	27.1 ± 2.0 b	8.3 ± 1.1 a	3.4 ± 0.3 a
	1.4	Full light	8.4 ± 0.6 a	108 ± 2 a	45.1 ± 3.9 a	18.5 ± 2.7 a	2.5 ± 0.2 a
		75% illumination	11.5 ± 1.1 a	137 ± 9 a	32.2 ± 3.4 ab	10.1 ± 1.5 a	3.2 ± 0.2 a
		20% illumination	8.9 ± 0.9 a	132 ± 4 a	31.1 ± 2.4 ab	10.6 ± 1.0 a	2.9 ± 0.6 a
	F value	F_L	3.46	5.30*	8.96**	7.62**	4.11*
		F_N	0.01	0.05	0.06	0.00	0.02
		F_LN	0.44	1.04	0.39	0.72	2.12
Ripening	2.8	Full light	9.9 ± 0.6 a	116 ± 1 b	43.5 ± 0.9 a	16.2 ± 0.4 a	2.7 ± 0.0 a
		75% illumination	8.1 ± 0.4 ab	144 ± 4 a	36.6 ± 0.3 c	12.9 ± 0.6 a	2.9 ± 0.2 a
		20% illumination	10.2 ± 0.6 a	134 ± 4 ab	29.6 ± 0.9 d	9.0 ± 0.5 b	3.3 ± 0.1 a
	1.4	Full light	8.7 ± 0.6 ab	118 ± 5 b	41.2 ± 0.6 ab	15.3 ± 0.4 a	2.7 ± 0.0 a
		75% illumination	9.2 ± 0.4 ab	140 ± 7 ab	37.6 ± 0.8 bc	13.8 ± 0.7 a	2.7 ± 0.1 a
		20% illumination	6.9 ± 0.1 a	121 ± 3 ab	20.6 ± 0.9 e	7.8 ± 1.1 b	2.7 ± 0.3 a
	F value	F_L	1.00	10.36**	182.61***	43.53***	1.44
		F_N	5.79*	1.35	21.07***	0.38	1.76
		F_LN	7.65**	1.00	15.16***	1.00	1.02

Developmental stage	Treatment		F_o/F_m	P_g(max) [µmol/(m²∙s)]	I_comp [µmol/(m²∙s)]	f_I(0) [µmol/(m²∙s)]	J_max [µmol/(m²∙s)]	V_c(max) [µmol/(m²∙s)]
Developmental stage	N ( mmol/L)	Light (L)	F_o/F_m	P_g(max) [µmol/(m²∙s)]	I_comp [µmol/(m²∙s)]	f_I(0) [µmol/(m²∙s)]	J_max [µmol/(m²∙s)]	V_c(max) [µmol/(m²∙s)]
Heading	2.8	Full light	0.82 ± 0.01 a	19.1 ± 0.7 ab	33.6 ± 2.6 a	31.8 ± 1.2 a	180 ± 21 a	138 ± 16 a
		75% illumination	0.82 ± 0.00 a	19.8 ± 2.0 a	24.1 ± 3.3 abc	32.8 ± 3.2 a	178 ± 18 a	142 ± 11 a
		20% illumination	0.82 ± 0.01 a	14.0 ± 0.4 ab	12.4 ± 3.3 bc	30.5 ± 0.8 a	135 ± 10 a	111 ± 13 a
	1.4	Full light	0.83 ± 0.00 a	15.2 ± 1.2 ab	23.0 ± 1.7 abc	26.3 ± 3.8 a	152 ± 2 a	131 ± 12 a
		75% illumination	0.83 ± 0.01 a	18.1 ± 0.7 ab	28.4 ± 4.4 ab	29.2 ± 1.4 a	156 ± 5 a	131 ± 8 a
		20% illumination	0.81 ± 0.00 a	12.6 ± 1.0 b	9.0 ± 2.2 c	28.4 ± 3.6 a	145 ± 5 a	124 ± 5 a
	F value	F_L	2.91	8.79**	13.12***	0.20	2.04	1.11
		F_N	0.07	4.31	1.11	1.97	1.07	0.02
		F_LN	1.05	0.49	1.96	0.13	0.88	0.45
Flowering	2.8	Full light	0.81 ± 0.00 a	14.1 ± 0.7 a	32.1 ± 1.2 a	25.8 ± 1.5 ab	141 ± 15 a	124 ± 22 a
		75% illumination	0.79 ± 0.00 a	14.8 ± 0.5 a	18.0 ± 3.7 a	42.0 ± 5.3 a	133 ± 8 a	124 ± 10 a
		20% illumination	0.81 ± 0.01 a	13.0 ± 2.1 a	30.6 ± 4.5 a	29.3 ± 2.5 ab	170 ± 32 a	128 ± 12 a
	1.4	Full light	0.81 ± 0.01 a	11.7 ± 1.5 a	26.9 ± 4.5 a	23.8 ± 3.6 b	152 ± 4 a	127 ± 5 a
		75% illumination	0.80 ± 0.00 a	14.3 ± 1.2 a	18.2 ± 3.5 a	34.5 ± 1.4 ab	168 ± 19 a	161 ± 43 a
		20% illumination	0.80 ± 0.01 a	9.6 ± 1.6 a	19.3 ± 2.9 a	32.4 ± 0.7 ab	126 ± 24 a	110 ± 20 a
	F value	F_L	1.6	1.8	3.4	7.0**	0.0	0.4
		F_N	0.0	2.3	2.3	0.6	0.0	0.1
		F_LN	1.5	0.4	0.9	1.1	1.4	0.5
Ripening	2.8	Full light	0.81 ± 0.01 a	16.7 ± 1.8 a	26.5 ± 4.1 a	28.8 ± 0.6 a	153 ± 5 a	122 ± 6 a
		75% illumination	0.81 ± 0.00 a	16.6 ± 0.7 a	28.0 ± 6.6 a	36.4 ± 3.6 a	170 ± 19 a	107 ± 5 a
		20% illumination	0.81 ± 0.00 a	11.4 ± 1.2 ab	10.1 ± 2.8 a	34.0 ± 1.7 a	121 ± 7 a	136 ± 30 a
	1.4	Full light	0.79 ± 0.01 a	11.6 ± 1.5 ab	35.6 ± 6.9 a	28.2 ± 3.2 a	124 ± 16 a	99 ± 14 a
		75% illumination	0.81 ± 0.01 a	15.8 ± 1.4 a	18.6 ± 2.8 a	32.4 ± 1.3 a	176 ± 14 a	136 ± 8 a
		20% illumination	0.80 ± 0.00 a	7.2 ± 0.6 b	20.4 ± 2.5 a	31.5 ± 3.9 a	114 ± 8 a	109 ± 7 a
	F value	F_L	2.6	10.3**	3.9	1.8	6.6*	0.3
		F_N	3.8	6.8*	0.5	0.8	0.6	0.3
		F_LN	1.5	1.1	1.9	0.1	0.6	1.5