Grain Yield and Quality and Physiological and Biochemical Characteristics of Flag Leaf in Early Rice as Affected by Submergence at Filling Stage

doi:10.16819/j.1001-7216.2016.5045

Abstract

Abstract:

The early hybrid rice Tianyou 998 and the early conventional rice Guinongzhan were submerged at filling stage to evaluate submergence effects on grain yield, rice quality, and physiological and biochemical characteristics of the flag leaf. The depth of submergence were 2/3, and all of rice plant height lasting 0d,1d,3d,5d and 7d(0 d as CK). The results showed that the plant height increased after submergence and the increments in plant height peaked after 5-7 days of submergence. The grain yield and rice quality decreased significantly after submergence at a depth of 2/3 plant height and complete submergence lasting 1-3 days at the filling stage, especially after complete submergence lasting 5-7 days. The yield decrease was mainly due to reduced effective panicle number after submergence. The grain yield and rice quality varied insignificantly with variety under the same submergence conditions. The free proline and MDA contents in flag leaf increased; however, the SPAD value and the SOD activity decreased following submergence at the filling stage and the variation increased as the depth and duration of submergence increased. The SPAD value and the MDA content, significantly or extremely significantly correlated with grain yield and rice quality at the filling stage, are two physiological indices.

Key words: submergence, early rice, filling stage, flag leaf, physicochemical properties, yield, quality

摘要：

以天优998和桂农占为试验材料,盆栽条件下在灌浆期进行2/3淹水和没顶淹水处理(淹水历时0 d、1 d、3 d、5 d和7 d,0 d为对照),对淹水后早稻剑叶理化特性以及产量和品质进行分析。结果表明,灌浆期水稻在1 d~3 d短期2/3和没顶淹水后产量和品质显著下降,淹水5 d~7 d产量下降最为严重。有效穗数下降是淹水导致产量下降的主要因素。相同淹水条件下,两个水稻材料间产量和品质变化差异不显著。灌浆期水稻淹水后水稻剑叶的游离脯氨酸和MDA含量升高,SPAD值和SOD酶活性下降,随淹水深度和持续时间的延长变幅增大。灌浆期淹水后水稻剑叶SPAD值和MDA含量与产量和品质呈显著或极显著相关,是反映淹水后水稻产量和品质变化生理指标。

关键词: 淹水, 早稻, 灌浆期, 剑叶, 理化特性, 产量, 品质

CLC Number:

Jing-hua JI, Zhi-guo HUO, Li-sheng TANG, Yao-dong DU, Fei HU. Grain Yield and Quality and Physiological and Biochemical Characteristics of Flag Leaf in Early Rice as Affected by Submergence at Filling Stage[J]. Chinese Journal OF Rice Science, 2016, 30(2): 181-192.

姬静华, 霍治国, 唐力生, 杜尧东, 胡飞. 早稻灌浆期淹水对剑叶理化特性及产量和品质的影响[J]. 中国水稻科学, 2016, 30(2): 181-192.

Figures/Tables 10

References 35

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材料与处理 Treatment	有效穗数 Number of productive panicles per pot	结实率 Seed setting rate /%	每穗粒数 Number of grains per panicle	千粒重 1000-grain weight /g	产量 Yield /(g·pot^-1)
天优998 Tianyou 998
2/3淹 2/3 submergence
对照CK	31.0±1.53 a	82.33±6.91 a	103.37±0.90 b	24.33±0.17 a	63.69±2.77 a (63.56±1.70 a)
1 d	21.0±0.58 b	76.17±2.53 ab	127.60±5.42 a	22.67±0.73 b	46.28±3.23 b (44.86±3.52 b)
3 d	16.0±1.15 c	74.57±0.86 ab	108.27±3.42 b	22.83±0.44 b	29.65±3.3 cd (28.39±2.07 c)
5 d	15.0±0.58 c	74.00±6.18 ab	133.40±8.57 a	21.17±0.44 c	31.13±2.43 c (30.98±3.93 cd)
7 d	14.3±2.96 c	62.60±1.99 b	110.63±3.77 b	21.17±0.33 c	20.94±4.13 d (20.29±4.31 d)
没顶淹 Complete submergence
对照CK	31.0±1.53 a	82.33±6.91 a	103.37±0.90 c	24.33±0.17 a	63.69±2.77 a (63.56±1.70 a)
1 d	15.7±1.76 b	65.69±1.48 b	136.63±2.15 ab	22.50±0.29 b	31.64±3.78 b (31.37±3.11 b)
3 d	14.0±1.53 b	59.77±5.03 b	142.13±6.94 a	21.83±0.33 b	25.50±1.70 bc (24.94±2.04 c)
5 d	12.7±0.88 b	55.53±0.43 b	133.37±7.45 ab	19.67±0.67 c	18.70±2.78 cd (18.44±1.24 d)
7 d	11.3±0.88 b	53.37±2.59 b	124.67±4.36 b	18.33±0.44 d	13.70±0.54 d (13.36±1.42 d)
桂农占 Guinongzhan
2/3淹 2/3 submergence
对照CK	23.0±1.53 a	85.23±1.50 a	118.53±0.35 b	23.00±0.00 a	53.32±2.64 a (53.15±3.22 a)
1 d	15.3±1.67 b	80.21±4.13 ab	129.83±1.89 a	22.00±0.50 ab	34.78±2.77 b (34.43±4.81 b)
3 d	14.0±0.58 b	78.76±5.07 ab	125.73±2.57 ab	21.33±0.33 abc	29.67±2.96 bc (23.00±0.65 c)
5 d	12.3±0.67 b	76.55±3.34 ab	132.03±4.40 a	20.67±0.60 bc	25.70±1.72 c (24.31±3.94 bc)
7 d	12.0±0.58 b	72.55±4.16 b	126.13±4.93 ab	19.83±0.88 c	21.81±2.32 c (21.70±3.42 c)
没顶淹 Complete submergence
对照CK	23.0±1.53 a	85.23±1.50 a	118.53±0.35 a	23.00±0.00 a	53.32±2.64 a (53.15±3.22 a)
1 d	14.3±0.33 b	82.45±0.73 ab	109.13±2.05 a	21.83±0.93 a	28.09±0.58 b (28.45±1.57 b)
3 d	14.0±1.00 b	74.50±3.8 abc	109.40±9.73 a	21.17±0.44 ab	24.05±2.60 b (22.01±1.37 bc)
5 d	13.3±1.20 bc	71.37±4.61 c	114.93±6.83 a	19.67±0.60 bc	21.30±1.92 bc (19.44±3.32 c)
7 d	10.3±1.33 c	70.45±4.32 c	113.67±5.91 a	18.17±0.73 c	15.47±3.56 c (15.01±1.47 c)

材料与处理 Treatment	有效穗数 Number of productive panicles per pot	结实率 Seed setting rate /%	每穗粒数 Number of grains per panicle	千粒重 1000-grain weight /g	产量 Yield /(g·pot^-1)
天优998 Tianyou 998
2/3淹 2/3 submergence
对照CK	31.0±1.53 a	82.33±6.91 a	103.37±0.90 b	24.33±0.17 a	63.69±2.77 a (63.56±1.70 a)
1 d	21.0±0.58 b	76.17±2.53 ab	127.60±5.42 a	22.67±0.73 b	46.28±3.23 b (44.86±3.52 b)
3 d	16.0±1.15 c	74.57±0.86 ab	108.27±3.42 b	22.83±0.44 b	29.65±3.3 cd (28.39±2.07 c)
5 d	15.0±0.58 c	74.00±6.18 ab	133.40±8.57 a	21.17±0.44 c	31.13±2.43 c (30.98±3.93 cd)
7 d	14.3±2.96 c	62.60±1.99 b	110.63±3.77 b	21.17±0.33 c	20.94±4.13 d (20.29±4.31 d)
没顶淹 Complete submergence
对照CK	31.0±1.53 a	82.33±6.91 a	103.37±0.90 c	24.33±0.17 a	63.69±2.77 a (63.56±1.70 a)
1 d	15.7±1.76 b	65.69±1.48 b	136.63±2.15 ab	22.50±0.29 b	31.64±3.78 b (31.37±3.11 b)
3 d	14.0±1.53 b	59.77±5.03 b	142.13±6.94 a	21.83±0.33 b	25.50±1.70 bc (24.94±2.04 c)
5 d	12.7±0.88 b	55.53±0.43 b	133.37±7.45 ab	19.67±0.67 c	18.70±2.78 cd (18.44±1.24 d)
7 d	11.3±0.88 b	53.37±2.59 b	124.67±4.36 b	18.33±0.44 d	13.70±0.54 d (13.36±1.42 d)
桂农占 Guinongzhan
2/3淹 2/3 submergence
对照CK	23.0±1.53 a	85.23±1.50 a	118.53±0.35 b	23.00±0.00 a	53.32±2.64 a (53.15±3.22 a)
1 d	15.3±1.67 b	80.21±4.13 ab	129.83±1.89 a	22.00±0.50 ab	34.78±2.77 b (34.43±4.81 b)
3 d	14.0±0.58 b	78.76±5.07 ab	125.73±2.57 ab	21.33±0.33 abc	29.67±2.96 bc (23.00±0.65 c)
5 d	12.3±0.67 b	76.55±3.34 ab	132.03±4.40 a	20.67±0.60 bc	25.70±1.72 c (24.31±3.94 bc)
7 d	12.0±0.58 b	72.55±4.16 b	126.13±4.93 ab	19.83±0.88 c	21.81±2.32 c (21.70±3.42 c)
没顶淹 Complete submergence
对照CK	23.0±1.53 a	85.23±1.50 a	118.53±0.35 a	23.00±0.00 a	53.32±2.64 a (53.15±3.22 a)
1 d	14.3±0.33 b	82.45±0.73 ab	109.13±2.05 a	21.83±0.93 a	28.09±0.58 b (28.45±1.57 b)
3 d	14.0±1.00 b	74.50±3.8 abc	109.40±9.73 a	21.17±0.44 ab	24.05±2.60 b (22.01±1.37 bc)
5 d	13.3±1.20 bc	71.37±4.61 c	114.93±6.83 a	19.67±0.60 bc	21.30±1.92 bc (19.44±3.32 c)
7 d	10.3±1.33 c	70.45±4.32 c	113.67±5.91 a	18.17±0.73 c	15.47±3.56 c (15.01±1.47 c)

材料与处理 Treatment	糙米率 Brown rice rate/%	精米率 Milled rice rate/%	整精米率 Head milled rice rate /%	垩白率 Percentage of chalky grain /%	垩白度 Chalkiness degree /%
天优998 Tianyou 998
2/3淹 3/2 submergence
对照CK	87.64±5.93 a	64.55±0.82 a	48.34±0.52 a	19.33±0.88 b	3.65±0.75 b
1 d	78.57±0.30 ab	63.99±0.24 a	44.96±2.36 a	20.33±0.88 b	4.77±0.93 b
3 d	77.64±1.35 ab	61.56±4.17 a	25.88±1.31 b	25.67±4.41b	6.71±0.80 b
5 d	77.64±0.83 ab	59.47±0.48 ab	25.50±0.35 b	47.00±2.00 a	13.00±0.80 a
7 d	77.05±2.84 b	55.31±0.76 b	23.56±0.41 b	50.00±4.04 a	16.29±1.97 a
没顶淹 Complete submergence
CK	87.64±5.93 a	64.55±0.82 a	48.34±0.52 a	19.33±0.88 c	3.65±0.75 d
1 d	78.09±1.07 ab	62.85±0.67 a	42.64±0.16 b	30.33±1.20 b	16.55±2.73 c
3 d	77.63±0.98 ab	56.53±2.87 b	25.95±1.76 c	33.67±1.45 b	18.34±1.20 c
5 d	77.27±0.62 b	55.90±2.06 b	24.59±0.20 c	49.33±1.86 a	28.73±4.28 b
7 d	74.85±3.80 b	54.79±0.95 b	19.03±0.70 d	52.00±2.08 a	40.00±1.86 a
桂农占 Guinongzhan
2/3淹 2/3 Submergence
对照CK	80.37±1.41 a	65.55±0.59 a	50.65±0.88 a	25.67±2.03 c	4.54±0.47 c
1 d	79.89±0.72 a	63.41±0.64 ab	41.19±0.37 b	29.00±1.15 c	7.70±2.19 c
3 d	79.19±0.45 ab	61.93±1.09 b	36.27±0.40 c	39.00±1.15 b	12.64±1.69 bc
5 d	78.91±0.13 ab	59.29±0.10 c	35.32±0.20 c	43.33±1.45 ab	20.26±1.01 ab
7 d	76.63±0.84 b	55.30±1.05 d	21.34±0.04 d	49.00±3.51 a	25.51±7.16 a
没顶淹 Complete submergence
对照CK	80.37±1.41 a	65.55±0.59 a	50.65±0.88 a	25.67±2.03 c	4.54±0.47 c
1 d	79.84±1.51 a	60.36±0.66 b	42.60±0.43 b	26.67±2.19 c	8.08±0.89 c
3 d	78.46±0.79 ab	59.07±0.34 b	37.58±0.44 c	54.67±4.81 b	18.37±0.71 b
5 d	77.73±0.9 ab	57.11±0.66 c	25.66±0.49 d	54.67±1.86 b	23.45±1.46 b
7 d	75.24±1.08 b	49.97±0.72 d	20.71±0.30 e	71.00±2.52 a	42.42±3.46 a

材料与处理 Treatment	糙米率 Brown rice rate/%	精米率 Milled rice rate/%	整精米率 Head milled rice rate /%	垩白率 Percentage of chalky grain /%	垩白度 Chalkiness degree /%
天优998 Tianyou 998
2/3淹 3/2 submergence
对照CK	87.64±5.93 a	64.55±0.82 a	48.34±0.52 a	19.33±0.88 b	3.65±0.75 b
1 d	78.57±0.30 ab	63.99±0.24 a	44.96±2.36 a	20.33±0.88 b	4.77±0.93 b
3 d	77.64±1.35 ab	61.56±4.17 a	25.88±1.31 b	25.67±4.41b	6.71±0.80 b
5 d	77.64±0.83 ab	59.47±0.48 ab	25.50±0.35 b	47.00±2.00 a	13.00±0.80 a
7 d	77.05±2.84 b	55.31±0.76 b	23.56±0.41 b	50.00±4.04 a	16.29±1.97 a
没顶淹 Complete submergence
CK	87.64±5.93 a	64.55±0.82 a	48.34±0.52 a	19.33±0.88 c	3.65±0.75 d
1 d	78.09±1.07 ab	62.85±0.67 a	42.64±0.16 b	30.33±1.20 b	16.55±2.73 c
3 d	77.63±0.98 ab	56.53±2.87 b	25.95±1.76 c	33.67±1.45 b	18.34±1.20 c
5 d	77.27±0.62 b	55.90±2.06 b	24.59±0.20 c	49.33±1.86 a	28.73±4.28 b
7 d	74.85±3.80 b	54.79±0.95 b	19.03±0.70 d	52.00±2.08 a	40.00±1.86 a
桂农占 Guinongzhan
2/3淹 2/3 Submergence
对照CK	80.37±1.41 a	65.55±0.59 a	50.65±0.88 a	25.67±2.03 c	4.54±0.47 c
1 d	79.89±0.72 a	63.41±0.64 ab	41.19±0.37 b	29.00±1.15 c	7.70±2.19 c
3 d	79.19±0.45 ab	61.93±1.09 b	36.27±0.40 c	39.00±1.15 b	12.64±1.69 bc
5 d	78.91±0.13 ab	59.29±0.10 c	35.32±0.20 c	43.33±1.45 ab	20.26±1.01 ab
7 d	76.63±0.84 b	55.30±1.05 d	21.34±0.04 d	49.00±3.51 a	25.51±7.16 a
没顶淹 Complete submergence
对照CK	80.37±1.41 a	65.55±0.59 a	50.65±0.88 a	25.67±2.03 c	4.54±0.47 c
1 d	79.84±1.51 a	60.36±0.66 b	42.60±0.43 b	26.67±2.19 c	8.08±0.89 c
3 d	78.46±0.79 ab	59.07±0.34 b	37.58±0.44 c	54.67±4.81 b	18.37±0.71 b
5 d	77.73±0.9 ab	57.11±0.66 c	25.66±0.49 d	54.67±1.86 b	23.45±1.46 b
7 d	75.24±1.08 b	49.97±0.72 d	20.71±0.30 e	71.00±2.52 a	42.42±3.46 a