Optimized Leaf Morphology and Delayed Senescence Boost Rice Yield via Enhanced Leaf and Canopy Photosynthesis

doi:10.1016/j.rsci.2025.12.005

Abstract

Abstract:

Four modern hybrid and four japonica rice varieties differing in biomass, yield, and daily biomass production rate during the grain-filling period (DBP_GF), were used to reveal the eco-physiological photosynthetic characteristics of high-yield and high-efficiency rice. Varietal differences were analyzed in leaf and canopy photosynthetic parameters, associated leaf morphological and anatomical traits (e.g., stomatal density, vein density, mesophyll cell arrangement), as well as differences in canopy light interception and leaf area index, and their effects on yield and biomass accumulation. Hybrid rice with yield higher than 11.0 t/hm² and DBP_GF higher than 200 kg/(hm²·d), and japonica rice with yield higher than 9.0 t/hm² and DBP_GF higher than 200 kg/(hm²·d), were classified as high-yield and high-efficiency varieties; other varieties were considered general types. Based on this criterion, two hybrid (Yongyou 2640 and Shanyou 63) and two japonica varieties (Huaidao 5 and Nangeng 5718) were categorized as high-yield and high-efficiency types, while the remaining two hybrid (Liangyoupeijiu and C Liangyou 513) and two japonica varieties (Suxiu 867 and Yangnongdao 1) were classified as general types. Results indicated that high-yield and high-efficiency varieties generally have higher leaf and canopy photosynthesis, superior leaf stomatal, vascular, and mesophyll structures that facilitate CO₂ diffusion and hydraulic transport, higher canopy light transmittance, and slower leaf area attenuation. Rice yield and biomass were positively correlated with photosynthetic parameters and closely linked to associated photosynthetic traits. Efficient rice production was attributed to coordinated improvements in leaf structure, canopy architecture, and delayed leaf area attenuation. This study provides important theoretical guidance for breeding high-efficiency rice varieties.

Key words: rice, photosynthesis, high yield and high efficiency, stomata, vein, mesophyll anatomy, canopy architecture, leaf area index

Ye Miao, Mao Yuxin, Yuan Rong, Zhang Dehai, Zhang Zujian. Optimized Leaf Morphology and Delayed Senescence Boost Rice Yield via Enhanced Leaf and Canopy Photosynthesis[J]. Rice Science, 2026, 33(2): 245-259.

Figures/Tables 11

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Variety type	Variety	Biomass at heading (t/hm²)		Biomass at maturity (t/hm²)			Yield (t/hm²)		Harvest index			DBP_GF [kg/(hm²·d)]		Biomass production type
Variety type	Variety	2023	2024	2023	2024		2023	2024	2023	2024		2023	2024	Biomass production type
Hybrid	Yongyou 2640	16.23 a	15.25 a	25.68 a	25.43 a	11.56 a		13.09 a	0.45 a	0.51 a	210.0 a		226.1 a	High-yield and high-efficiency
	Shanyou 63	14.77 b	14.80 a	25.77 a	23.92 b	11.11 ab		11.26 b	0.43 b	0.47 b	219.9 a		202.7 b	High-yield and high-efficiency
	Liangyoupeijiu	14.29 b	14.98 a	24.85 a	22.90 b	10.14 b		10.86 bc	0.41 c	0.47 b	192.0 ab		176.0 c	General
	C Liangyou 513	14.97 b	13.33 b	22.67 b	19.93 c	7.43 c		10.36 cd	0.33 d	0.52 a	171.0 b		146.6 d	General
	Mean	15.06 A	14.59 A	24.74 A	23.04 A	10.06 A		11.39 A	0.40 A	0.49 A	198.2 A		187.9 A
Japonica	Huaidao 5	11.03 a	11.95 a	20.40 ab	21.36 a	9.05 b		10.24 ab	0.44 ab	0.48 a	220.4 a		235.4 a	High-yield and high-efficiency
	Nangeng 5718	10.99 a	13.22 a	22.11 a	21.42 a	9.83 a		9.98 b	0.44 ab	0.47 a	217.6 b		205.2 b	High-yield and high-efficiency
	Suxiu 867	10.36 a	10.18 b	19.07 b	19.32 b	8.72 b		6.86 d	0.46 a	0.35 b	187.0 c		182.8 c	General
	Yangnongdao 1	10.20 a	10.04 b	19.15 b	18.51 b	7.92 c		8.28 c	0.41 b	0.45 a	176.7 c		169.4 c	General
	Mean	10.64 B	11.85 B	20.18 B	20.15 B	8.88 B		8.84 B	0.44 A	0.44 A	200.4 A		197.1 A

Variety type	Variety	Biomass at heading (t/hm²)		Biomass at maturity (t/hm²)			Yield (t/hm²)		Harvest index			DBP_GF [kg/(hm²·d)]		Biomass production type
Variety type	Variety	2023	2024	2023	2024		2023	2024	2023	2024		2023	2024	Biomass production type
Hybrid	Yongyou 2640	16.23 a	15.25 a	25.68 a	25.43 a	11.56 a		13.09 a	0.45 a	0.51 a	210.0 a		226.1 a	High-yield and high-efficiency
	Shanyou 63	14.77 b	14.80 a	25.77 a	23.92 b	11.11 ab		11.26 b	0.43 b	0.47 b	219.9 a		202.7 b	High-yield and high-efficiency
	Liangyoupeijiu	14.29 b	14.98 a	24.85 a	22.90 b	10.14 b		10.86 bc	0.41 c	0.47 b	192.0 ab		176.0 c	General
	C Liangyou 513	14.97 b	13.33 b	22.67 b	19.93 c	7.43 c		10.36 cd	0.33 d	0.52 a	171.0 b		146.6 d	General
	Mean	15.06 A	14.59 A	24.74 A	23.04 A	10.06 A		11.39 A	0.40 A	0.49 A	198.2 A		187.9 A
Japonica	Huaidao 5	11.03 a	11.95 a	20.40 ab	21.36 a	9.05 b		10.24 ab	0.44 ab	0.48 a	220.4 a		235.4 a	High-yield and high-efficiency
	Nangeng 5718	10.99 a	13.22 a	22.11 a	21.42 a	9.83 a		9.98 b	0.44 ab	0.47 a	217.6 b		205.2 b	High-yield and high-efficiency
	Suxiu 867	10.36 a	10.18 b	19.07 b	19.32 b	8.72 b		6.86 d	0.46 a	0.35 b	187.0 c		182.8 c	General
	Yangnongdao 1	10.20 a	10.04 b	19.15 b	18.51 b	7.92 c		8.28 c	0.41 b	0.45 a	176.7 c		169.4 c	General
	Mean	10.64 B	11.85 B	20.18 B	20.15 B	8.88 B		8.84 B	0.44 A	0.44 A	200.4 A		197.1 A

Variety type	Variety	A_canopy [μmol/(m²·s)]	A_leaf [μmol/(m²·s)]	g_s [mol/(m²·s)]	E [mmol/(m²·s)]	K_leaf [mmol/(m²·s·Mpa)]
Hybrid	Yongyou 2640	45.04 a	26.95 a	0.44 a	9.34 a	14.77 a
	Shanyou 63	37.60 b	23.91 b	0.40 ab	8.38 b	11.06 b
	Liangyoupeijiu	33.64 c	22.83 bc	0.39 ab	8.42 ab	11.27 b
	C Liangyou 513	34.81 c	21.40 c	0.35 b	7.00 c	8.84 c
	Mean	37.77 B	23.77 A	0.40 A	8.28 A	11.48 A
Japonica	Huaidao 5	46.72 a	26.16 a	0.36 a	7.28 a	10.90 a
	Nangeng 5718	40.75 b	23.85 b	0.33 a	7.33 a	10.65 a
	Suxiu 867	36.20 c	19.98 c	0.30 a	6.66 a	9.34 a
	Yangnongdao 1	41.77 b	21.19 c	0.30 a	6.80 a	8.80 a
	Mean	41.36 A	22.80 A	0.32 B	7.02 B	9.92 A

Variety type	Variety	A_canopy [μmol/(m²·s)]	A_leaf [μmol/(m²·s)]	g_s [mol/(m²·s)]	E [mmol/(m²·s)]	K_leaf [mmol/(m²·s·Mpa)]
Hybrid	Yongyou 2640	45.04 a	26.95 a	0.44 a	9.34 a	14.77 a
	Shanyou 63	37.60 b	23.91 b	0.40 ab	8.38 b	11.06 b
	Liangyoupeijiu	33.64 c	22.83 bc	0.39 ab	8.42 ab	11.27 b
	C Liangyou 513	34.81 c	21.40 c	0.35 b	7.00 c	8.84 c
	Mean	37.77 B	23.77 A	0.40 A	8.28 A	11.48 A
Japonica	Huaidao 5	46.72 a	26.16 a	0.36 a	7.28 a	10.90 a
	Nangeng 5718	40.75 b	23.85 b	0.33 a	7.33 a	10.65 a
	Suxiu 867	36.20 c	19.98 c	0.30 a	6.66 a	9.34 a
	Yangnongdao 1	41.77 b	21.19 c	0.30 a	6.80 a	8.80 a
	Mean	41.36 A	22.80 A	0.32 B	7.02 B	9.92 A

Variety type	Variety	SL_upper (μm)	SL_lower (μm)		SD_lower (No./mm²)	SD_upper/SD_lower
Hybrid	Yongyou 2640	16.80 a	17.55 a	696.89 b	599.19 c	1.16 a
	Shanyou 63	15.82 ab	16.12 ab	705.52 ab	607.62 bc	1.16 a
	Liangyoupeijiu	14.57 bc	14.44 bc	717.14 a	662.31 a	1.08 b
	C Liangyou 513	13.56 c	13.69 c	689.94 b	625.14 b	1.10 b
	Mean	15.19 A	15.45 A	702.37 A	623.56 A	1.13 B
Japonica	Huaidao 5	17.31 a	14.39 ab	693.58 a	523.23 a	1.33 a
	Nangeng 5718	16.21 ab	15.05 a	641.39 ab	521.55 a	1.23 a
	Suxiu 867	15.14 b	13.79 b	599.00 b	479.35 a	1.25 a
	Yangnongdao 1	15.87 ab	14.06 ab	528.36 c	459.10 a	1.15 a
	Mean	16.13 A	14.32 B	615.58 B	495.81 B	1.24 A