弱光涝渍复合胁迫对夏玉米产量及光合特性的影响

doi:10.3864/j.issn.0578-1752.2021.18.004

摘要/Abstract

摘要：

【目的】旨在探讨不同生育时期弱光涝渍复合胁迫影响夏玉米产量和光合特性的生理机制。【方法】选用DH605为试验材料,通过在大田条件下设置不同生育时期遮阴、淹水以及遮阴+淹水处理,即分别为三叶期淹水（V3-W）、拔节期淹水（V6-W）、开花期淹水（VT-W）;三叶期遮阴（V3-S）、拔节期遮阴（V6-S）、开花期遮阴（VT-S）;三叶期遮阴淹水（V3-S-W）、拔节期遮阴淹水（V6-S-W）、开花期遮阴淹水（VT-S-W）,并以自然光和常规水分处理为对照（CK）,以模拟不同生育时期的寡照、涝渍及其复合胁迫,研究不同生育时期遮阴淹水复合处理对夏玉米产量、光合特性以及干物质的积累与分配的影响。【结果】遮阴淹水后,夏玉米叶面积指数（LAI）下降,叶片叶绿素相对含量（SPAD值）显著降低,净光合速率（Pn）、蒸腾速率（Tr）、气孔导度（Gs）显著下降,胞间二氧化碳浓度（Ci）小幅上升,其中V3-S-W、V6-S-W和VT-S-W处理的Pn较CK分别下降43.7%、41.1%和35.1%,且遮阴淹水复合处理后夏玉米净光合速率的下降幅度大于遮阴、淹水等单一胁迫。遮阴淹水复合处理引发夏玉米光合性能降低,导致夏玉米干物质积累能力及向籽粒分配比例的下降并最终导致产量降低。从2018年和2019年的产量平均值来看,V3-S-W、V6-S-W和VT-S-W处理的产量较CK分别降低32.5%、28.3%和24.7%。与单一遮阴和淹水处理相比,V3-S-W处理的产量较V3-S和V3-W处理分别降低26.3%和13.1%;V6-S-W处理的产量较V6-S和V6-W处理分别下降14.9%和6.2%;VT-S-W处理的产量较VT-S和VT-W处理分别降低2.9%和15.0%。【结论】遮阴淹水复合处理导致夏玉米群体叶面积指数显著降低,叶绿素相对含量下降,光合性能受到抑制,进而导致夏玉米光合同化物的积累与分配受阻,最终导致产量显著下降。三叶期遮阴淹水对夏玉米光合特性和产量的下降幅度的影响最大,拔节期次之,花期的影响较小。同时,遮阴淹水复合处理造成的光合特性及产量下降程度高于任一单处理。

关键词: 夏玉米, 遮阴, 淹水, 弱光涝渍复合胁迫, 产量, 光合特性

Abstract:

【Objective】 The purpose of this study was to investigate the physiological mechanism of shade and waterlogging combined treatment on photosynthetic characteristics of summer maize during different growth stages. 【Method】 DH605 was selected as the test variety. Shading treatment, waterlogging treatment and shading + waterlogging treatment were set in different growth periods under field conditions, including waterlogging at the third leaf stage (V3-W), the sixth leaf stage (V6-W), and flowering stage (VT-W); shading at V3 (V3-S), V6 (V6-S), and VT (VT-S); waterlogging and shading combined treatment at V3 (V3-S-W), V6 (V6-S-W), and VT stage (VT-S-W). The effects of shading and waterlogging compound treatment on yield, photosynthetic characteristics and dry matter accumulation and distribution of summer maize were studied, and the differences of photosynthetic characteristics and yield between single treatment and compound treatment were compared. 【Result】 After shading and waterlogging, the LAI, relative chlorophyll content, net photosynthetic rate (Pn), Transpiration rate (Tr), and stomatal conductance (Gs) of summer maize were significantly decreased. Compared with CK, the Pn under V3-S-W, V6-S-W and VT-S-W was significantly decreased by 43.7%, 41.1% and 35.1%, respectively. Moreover, the net photosynthetic rate of the combined treatment of shading and waterlogging was decreased more than that of shading or waterlogging treatment. The combined treatment of shading and waterlogging resulted in the decrease of photosynthetic performance of summer maize, leading to the decrease of dry matter accumulation ability and grain distribution ratio of summer maize, and thus resulting in a significant decrease of maize yield. Compared with CK, the yield under V3-S-W, V6-S-W and VT-S-W were reduced by 32.5%, 28.3% and 24.7%, respectively. Compared with single shading or flooding treatment, the yield under V3-S-W was 26.3% and 13.1% lower than that under V3-S and V3-W, respectively. Compared with V6-S and V6-W, the grain yield under V6-S-W was decreased by 14.9% and 6.2%, respectively. Compared with VT-S and VT-W, the yield of VT-S-W was reduced by 2.9% and 15.0%, respectively. 【Conclusion】 Combined treatment with shading and waterlogging resulted in significantly reduced LAI, decreased relative chlorophyll content and inhibited photosynthetic performance of summer maize, which led to hindered accumulation and distribution of photosynthetic compounds in summer maize, and thus resulting in the decrease of maize yield. Combined treatment with shading and waterlogging at V3 stage had the greatest effect on photosynthetic characteristics and yield of summer maize, followed by V6 and VT stage. At the same time, the photosynthetic characteristics and yield decreased by combined treatment with shading and waterlogging were higher than either single treatment.

Key words: summer maize, shade, waterlogging, combined stress of shade and waterlogging, yield, photosynthetic characteristics

于维祯,张晓驰,胡娟,邵靖宜,刘鹏,赵斌,任佰朝. 弱光涝渍复合胁迫对夏玉米产量及光合特性的影响[J]. 中国农业科学, 2021, 54(18): 3834-3846.

YU WeiZhen,ZHANG XiaoChi,HU Juan,SHAO JingYi,LIU Peng,ZHAO Bin,REN BaiZhao. Combined Effects of Shade and Waterlogging on Yield and Photosynthetic Characteristics of Summer Maize[J]. Scientia Agricultura Sinica, 2021, 54(18): 3834-3846.

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年份处理 Treatment		2018				2019
年份处理 Treatment		千粒重 1000-grain weight (g)	穗粒数 kernels per spike	公顷穗数 Ear number (ear)	产量 Yield (kg·hm^-2)	千粒重 1000-grain weight (g)	穗粒数 kernels per spike	公顷穗数 Ear number (ear)	产量 Yield (kg·hm^-2)
CK		375ab	544a	67496	13770a	348a	496a	67496	13563a
V3-W		377a	477e	65962	11897cd	308de	364g	62304	8114f
V3-S		373abc	544a	65962	13386a	330b	480b	65850	12130b
V3-S-W		381a	450f	64561	11094e	304e	325h	64122	7378g
V6-W		365c	487d	64823	11528de	314d	375ef	62304	8538e
V6-S		378a	528b	63063	12590b	326bc	474c	64121	11542c
V6-S-W		373abc	464e	64741	11225e	314d	369fg	62292	8409ef
VT-W		366bc	518c	64684	12267bc	321c	462d	65850	11397c
VT-S		364c	518c	67496	12754b	326bc	372ef	64121	9051d
VT-S-W		373abc	480de	64624	11587de	321c	376e	64121	9025d
显著性 Significant	S	ns	**	-	**	**	**	-	**
	W	ns	**	-	**	**	**	-	**
	G	**	**	-	*	**	**	-	**
	S×W	ns	**	-	ns	**	*	-	**
	S×G	ns	**	-	ns	ns	**	-	**
	W×G	ns	**	-	*	**	**	-	**
	S×W×G	ns	**	-	ns	ns	**	-	**

处理 Treatment		净光合速率 Pn (μmol·m^-2·s^-1)	蒸腾速率 Tr (μmol·m^-2·s^-1)	气孔导度 Gs ((μmol·m^-2·s^-1)	胞间二氧化碳浓度 Ci (μmol·m^-2·s^-1)
CK		37.7a	6.75a	357a	172c
V3-W		21.5e	4.63d	190e	248a
V3-S		35.9ab	5.76b	330bc	185bc
V3-S-W		21.2e	4.11d	181e	260a
V6-W		22.7de	4.71cd	197de	238a
V6-S		35.9ab	5.69b	346ab	201b
V6-S-W		22.2e	3.99e	189e	239a
VT-W		35.3b	5.66b	316c	189bc
VT-S		25.4c	5.30bc	212d	182bc
VT-S-W		24.5cd	5.30bc	194de	179bc
显著性 Significant	S	**	**	**	**
	W	**	**	**	*
	G	**	**	ns	**
	S×W	**	*	*	ns
	S×G	**	ns	ns	**
	W×G	**	**	ns	**
	S×W×G	ns	ns	ns	ns

年份 Year	处理 Treatment	茎 Stem		叶 Leaf		粒 Grain		轴 Spike axis		单株 Total dry matter (g/plant)
年份 Year	处理 Treatment	干重 Dry matter (g/plant)	比例 Proportion (%)	干重 Dry matter (g/plant)	比例 Proportion (%)	干重 Dry matter (g/plant)	比例 Proportion (%)	干重 Dry matter (g/plant)	比例 Proportion (%)	单株 Total dry matter (g/plant)
2018	CK	71.0ab	21.8%	37.0bc	11.4%	199.0a	61.1%	18.0b	5.5%	325.5a
	V3-W	73.0ab	26.7%	44.7ab	16.4%	135.0d	49.3%	21.0ab	7.7%	273.7d
	V3-S	68.0b	21.9%	39.6bc	12.7%	186.0ab	59.8%	17.5b	5.6%	311.1a
	V3-S-W	75.0a	27.5%	42.2b	15.5%	132.0d	48.5%	23.0a	8.4%	272.2d
	V6-W	66.8b	23.8%	45.4ab	16.5%	150.4c	53.0%	19.0b	6.7%	283.6cd
	V6-S	65.0b	21.3%	41.6bc	13.7%	180.3b	59.2%	17.7b	5.8%	304.6bc
	V6-S-W	66.2b	23.7%	52.7a	18.9%	141.0d	50.5%	19.5b	7.0%	279.3d
	VT-W	70.5b	23.6%	32.2c	10.8%	175.0b	58.7%	20.5ab	6.9%	298.2c
	VT-S	69.5b	24.0%	39.4bc	13.6%	161.0c	55.6%	19.8b	6.8%	289.7c
	VT-S-W	69.9b	24.4%	36.6bc	12.8%	159.0c	55.5%	20.8ab	7.3%	286.3cd
2019	CK	76.7a	21.4%	36.9a	10.3%	202.4a	59.8%	22.6a	6.7%	338.6a
	V3-W	46.5f	24.9%	25.3de	13.6%	97.5de	52.3%	17.6c	9.4%	186.5f
	V3-S	62.0c	21.2%	32.9ab	11.2%	174.8b	59.8%	22.7a	7.8%	292.5c
	V3-S-W	54.2e	30.9%	21.6e	12.3%	96.2e	49.1%	13.5d	7.7%	185.4g
	V6-W	64.2c	29.9%	28.1cd	13.1%	105.7d	49.2%	16.7bc	9.6%	214.7e
	V6-S	71.2b	24.5%	31.8bc	10.9%	167.7b	57.7%	20.1bc	6.9%	290.8c
	V6-S-W	58.2d	27.5%	27.4cd	13.0%	105.9d	50.9%	10.2d	7.2%	211.4e
	VT-W	72.2b	23.9%	37.9a	12.5%	167.9b	55.5%	24.7a	8.2%	302.7b
	VT-S	76.5a	28.5%	37.0a	13.8%	132.8c	49.5%	22.1ab	8.2%	268.4d
	VT-S-W	74.1ab	28.0%	37.4a	14.1%	132.4c	50.1%	20.5bc	7.8%	264.4d