Effects of Drought Priming During Tillering Stage on Panicle Development and Yield Formation Under High Temperature During Panicle Initiation Stage in Rice

doi:10.16819/j.1001-7216.2024.231110

Abstract

Abstract:

【Objective】 The aim of this study was to investigate the impact of drought priming during the tillering stage on rice panicle development and yield formation under high temperatures during the panicle initiation stage, along with the underlying physiological mechanisms.【Method】 Two rice varieties, Liangyoupeijiu (heat-sensitive) and Shanyou 63 (heat-tolerant), were chosen for the study. A pot experiment was conducted with two water treatments (flooding irrigation and drought priming during tillering stage) and two temperature treatments (normal temperature and high temperature during panicle initiation stage). The effects of drought priming on spikelet differentiation and degradation, pollen viability, spikelet fertility, spikelet size, grain yield, and underlying physiological characteristics were evaluated.【Result】 Under normal temperature treatment, there was no significant difference in grain yield between flooding irrigation and drought priming for both varieties. However, under high temperature treatment, drought priming led to a significant increase in seed setting rate and 1000-grain weight, resulting in a 54.0% increase in grain yield for Liangyoupeijiu and a 20.1% increase for Shanyou 63 compared to flooding irrigation. Drought priming also resulted in the significant increases in the activities of peroxidase and superoxide dismutase and significant decrease in malondialdehyde content of spikelet, and significant increase in the pollen viability by 26.0%, and in spikelet fertility by 39.0% in Liangyoupeijiu under high temperature treatment. Under flooding irrigation, high temperature treatment resulted in significant reductions in spikelet size and differentiated spikelet number for both varieties compared to normal temperature treatment. However, under high temperature treatment, drought priming led to significant increases in the contents of panicle non-structural carbohydrates and spikelet cytokinins (trans-zeatin and trans-zeatin-riboside), as well as increases in spikelet length, width, and differentiated spikelet number across both varieties.【Conclusion】 Drought priming during the tillering stage effectively mitigated the negative effects of high temperature stress on spikelet development and fertility by enhancing antioxidant enzyme activities, cytokinin content in spikelets, and non-structural carbohydrate levels in panicles. This resulted in improved rice yield formation under high temperature stress conditions, offering insights for rice production in regions prone to high temperature stress.

Key words: drought priming, high temperature during panicle initiation stage, spikelet fertility, spikelet development, grain yield

摘要：

【目的】明确分蘖期干旱锻炼对幼穗分化期高温下水稻穗发育和产量形成的影响，并探究其生理机理。【方法】以两优培九(热敏感型)和汕优63(耐热型)为材料，在盆栽条件下设置全生育期淹灌和分蘖期干旱锻炼、幼穗分化期适温和高温共四种水分和温度处理组合，研究干旱锻炼对高温胁迫下水稻颖花分化与退化、花粉活力、颖花育性、颖花大小、产量及穗生理特性的影响。【结果】与淹灌相比，在适温下干旱锻炼对两个品种产量无显著影响，但高温下干旱锻炼后两优培九和汕优63的产量分别显著提高了54.0%和20.1%，这主要是因为结实率和千粒重显著提高。与淹灌相比，幼穗分化期高温下，分蘖期干旱锻炼显著增强两优培九颖花过氧化物酶和超氧化物歧化酶活性，降低了丙二醛含量，其花粉活力和颖花育性分别显著提高了26.0%和39.0%。与适温相比，全生育期淹灌下，高温显著降低了两个品种的颖花大小和总颖花分化数。与淹灌相比，分蘖期干旱锻炼显著提高了幼穗分化期高温下两品种穗非结构性碳水化合物含量和颖花细胞分裂素(反式玉米素+反式玉米素核苷)含量，两个品种颖花长、颖花宽和总颖花分化数平均显著增加了3.2%、4.4%和15.0%。【结论】分蘖期干旱锻炼可通过增加抗氧化酶活性、非结构性碳水化合物和细胞分裂素含量来促进颖花发育和提高颖花育性，进而缓解幼穗分化期高温对水稻产量的不利影响，研究结果可为高温热害频发地区的水稻生产实践提供理论指导。

关键词: 干旱锻炼, 幼穗分化期高温, 颖花育性, 颖花发育, 产量

ZHAO Yiting, XIE Keran, GAO Ti, CUI Kehui. Effects of Drought Priming During Tillering Stage on Panicle Development and Yield Formation Under High Temperature During Panicle Initiation Stage in Rice[J]. Chinese Journal OF Rice Science, 2024, 38(3): 277-289.

赵艺婷, 谢可冉, 高逖, 崔克辉. 水稻分蘖期干旱锻炼对幼穗分化期高温下穗发育和产量形成的影响[J]. 中国水稻科学, 2024, 38(3): 277-289.

Figures/Tables 10

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品种 Variety	处理 Treatment	产量 Yield(g/plant)	单株穗数 Panicles per plant	每穗粒数 Grains per panicle	结实率 Seed setting rate(%)	千粒重 1000-grain weight(g)
两优培九	W1T1	24.6±0.1 a	11.4±0.6 a	133.7±2.8 a	69.0±1.7 a	23.6±0.1 a
Liangyoupeijiu	W2T1	24.4±1.0 a	11.9±0.5 a	133.2±2.0 a	64.7±2.1 a	23.9±0.3 a
	W1T2	15.5±1.1 b	11.0±0.2 a	131.6±5.6 a	48.5±3.1 b	22.3±0.2 b
	W2T2	23.9±1.6 a	12.0±0.7 a	131.9±11.6 a	66.2±1.8 a	23.3±0.3 a
汕优63	W1T1	35.5±0.4 a*	12.3±0.4 a	133.9±5.8 ab	84.6±3.5 a*	25.6±0.1 a*
Shanyou 63	W2T1	34.6±1.9 a*	13.3±0.2 a	142.5±8.3 a	73.4±1.5 b*	25.2±0.1 a*
	W1T2	25.9±1.2 b*	12.3±0.4 a	119.7±3.1 b	78.7±3.5 ab*	22.6±0.1 c
	W2T2	31.2±1.2 a*	13.4±0.6 a	128.1±2.3 ab	78.4±1.4 ab*	23.5±0.2 b
ANOVA
品种 Variety(V)		++	ns	ns	++	++
温度 Temperature(T)		++	ns	ns	ns	++
水分 Water content(W)		+	++	ns	ns	+
V×T		ns	ns	ns	ns	++
V×W		ns	ns	ns	++	ns
T×W		++	ns	ns	++	+
V×T×W		ns	ns	ns	ns	ns

品种 Variety	处理 Treatment	产量 Yield(g/plant)	单株穗数 Panicles per plant	每穗粒数 Grains per panicle	结实率 Seed setting rate(%)	千粒重 1000-grain weight(g)
两优培九	W1T1	24.6±0.1 a	11.4±0.6 a	133.7±2.8 a	69.0±1.7 a	23.6±0.1 a
Liangyoupeijiu	W2T1	24.4±1.0 a	11.9±0.5 a	133.2±2.0 a	64.7±2.1 a	23.9±0.3 a
	W1T2	15.5±1.1 b	11.0±0.2 a	131.6±5.6 a	48.5±3.1 b	22.3±0.2 b
	W2T2	23.9±1.6 a	12.0±0.7 a	131.9±11.6 a	66.2±1.8 a	23.3±0.3 a
汕优63	W1T1	35.5±0.4 a*	12.3±0.4 a	133.9±5.8 ab	84.6±3.5 a*	25.6±0.1 a*
Shanyou 63	W2T1	34.6±1.9 a*	13.3±0.2 a	142.5±8.3 a	73.4±1.5 b*	25.2±0.1 a*
	W1T2	25.9±1.2 b*	12.3±0.4 a	119.7±3.1 b	78.7±3.5 ab*	22.6±0.1 c
	W2T2	31.2±1.2 a*	13.4±0.6 a	128.1±2.3 ab	78.4±1.4 ab*	23.5±0.2 b
ANOVA
品种 Variety(V)		++	ns	ns	++	++
温度 Temperature(T)		++	ns	ns	ns	++
水分 Water content(W)		+	++	ns	ns	+
V×T		ns	ns	ns	ns	++
V×W		ns	ns	ns	++	ns
T×W		++	ns	ns	++	+
V×T×W		ns	ns	ns	ns	ns

品种 Variety	处理 Treatment	抽穗期Heading stage		成熟期Mature stage
品种 Variety	处理 Treatment	颖花长 Spikelet length(mm)	颖花宽 Spikelet width(mm)	籽粒长 Grain length(mm)	籽粒宽 Grain width(mm)
两优培九	W1T1	9.07±0.02 a*	3.00±0.03 a	8.85±0.05 a*	2.62±0.05 b
Liangyoupeijiu	W2T1	8.97±0.00 a*	2.98±0.04 a	8.82±0.02 ab*	2.69±0.02 a
	W1T2	8.77±0.07 b*	2.82±0.02 b	8.72±0.03 b*	2.54±0.03 c
	W2T2	9.00±0.13 a*	2.96±0.07 a	8.80±0.08 ab*	2.63±0.02 b
汕优63	W1T1	8.40±0.11 a	3.28±0.04 a*	8.44±0.06 a	2.96±0.00 a*
Shanyou 63	W2T1	8.37±0.02 a	3.22±0.01 a*	8.48±0.04 a	2.94±0.02 a*
	W1T2	7.98±0.01 b	2.97±0.02 c*	8.15±0.07 c	2.78±0.01 c*
	W2T2	8.28±0.03 a	3.09±0.01 b*	8.32±0.09 b	2.87±0.01 b*
ANOVA
品种 Variety(V)		++	++	++	++
温度 Temperature(T)		+	++	+	+
水分 Water content(W)		ns	ns	ns	++
V×T		ns	ns	ns	ns
V×W		ns	ns	ns	+
T×W		+	+	ns	++
V×T×W		ns	ns	ns	+

品种 Variety	处理 Treatment	抽穗期Heading stage		成熟期Mature stage
品种 Variety	处理 Treatment	颖花长 Spikelet length(mm)	颖花宽 Spikelet width(mm)	籽粒长 Grain length(mm)	籽粒宽 Grain width(mm)
两优培九	W1T1	9.07±0.02 a*	3.00±0.03 a	8.85±0.05 a*	2.62±0.05 b
Liangyoupeijiu	W2T1	8.97±0.00 a*	2.98±0.04 a	8.82±0.02 ab*	2.69±0.02 a
	W1T2	8.77±0.07 b*	2.82±0.02 b	8.72±0.03 b*	2.54±0.03 c
	W2T2	9.00±0.13 a*	2.96±0.07 a	8.80±0.08 ab*	2.63±0.02 b
汕优63	W1T1	8.40±0.11 a	3.28±0.04 a*	8.44±0.06 a	2.96±0.00 a*
Shanyou 63	W2T1	8.37±0.02 a	3.22±0.01 a*	8.48±0.04 a	2.94±0.02 a*
	W1T2	7.98±0.01 b	2.97±0.02 c*	8.15±0.07 c	2.78±0.01 c*
	W2T2	8.28±0.03 a	3.09±0.01 b*	8.32±0.09 b	2.87±0.01 b*
ANOVA
品种 Variety(V)		++	++	++	++
温度 Temperature(T)		+	++	+	+
水分 Water content(W)		ns	ns	ns	++
V×T		ns	ns	ns	ns
V×W		ns	ns	ns	+
T×W		+	+	ns	++
V×T×W		ns	ns	ns	+

品种 Variety	处理 Treatment	总枝梗分化数 NBD (No./panicle)	一次枝梗分化数 NPBD (No./panicle)	二次枝梗分化数 NSBD (No./panicle)	一次枝梗退化数 NPBG (No./panicle)	二次枝梗退化数 NSBG (No./panicle)
两优培九	W1T1	73.7±2.3 a	12.8±0.4 a	60.9±1.9 a	0.0±0.0 a	22.3±2.3 ab
Liangyoupeijiu	W2T1	68.0±1.6 a	12.3±0.2 a	55.7±1.5 a	0.0±0.0 a	18.9±1.6 ab
	W1T2	66.8±1.5 a	12.1±0.1 a	54.7±1.4 a	0.0±0.0 a	23.8±1.7 a
	W2T2	68.0±1.9 a	12.2±0.1 a	55.8±1.8 a	0.0±0.0 a	18.6±1.1 b
汕优63	W1T1	67.3±0.7 a	14.0±0.3 a	53.3±1.0 a*	0.0±0.0 a	17.7±1.2 a
Shanyou 63	W2T1	67.0±2.1 a	13.2±0.7 a	53.8±1.5 a	0.0±0.0 a	17.2±3.6 a
	W1T2	64.4±0.2 a	13.4±0.1 a*	51.0±0.3 a	0.0±0.0 a	22.4±1.3 a
	W2T2	65.8±1.0 a	13.1±0.1 a*	52.7±1.1 a	0.0±0.0 a	17.9±0.9 a
ANOVA
品种 Variety(V)		ns	ns	+	ns	ns
温度 Temperature(T)		+	ns	+	ns	ns
水分 Water content(W)		ns	ns	ns	ns	ns
V×T		ns	ns	ns	ns	ns
V×W		ns	ns	ns	ns	ns
T×W		ns	ns	ns	ns	ns
V×T×W		ns	ns	ns	ns	ns