Wheat Straw Burial Improves Physiological Traits, Yield and Grain Quality of Rice by Regulating Antioxidant System and Nitrogen Assimilation Enzymes under Alternate Wetting and Drying Irrigation

doi:10.1016/j.rsci.2022.07.007

Abstract

Abstract:

Wheat straw burial has great potential to sustain rice production under alternate wetting and drying (AWD) irrigation. A field experiment was conducted with three wheat straw burial treatments, including without straw burial (NSB), with light straw burial of 300 kg/hm² (LSB) and dense straw burial of 800 kg/hm² (DSB), as well as three AWD regimes: alternate wetting/moderate drying (AWMD), alternate wetting/severe drying (AWSD) and alternate wetting/critical drying (AWCD). The rice growth and grain quality were higher in LSB and NSB than those in NSB under the same AWD regime. The AWMD × DSB treatment resulted in the highest yield, brown rice rate, milled rice rate, amylose content and protein content. Conversely, the AWCD × NSB treatment led to the lowest yield, brown rice rate, milled rice rate, amylose content and protein content. The active absorption area and nitrate reductase activity of roots were higher in the AWMD × DSB treatment than those in the AWCD × NSB treatment, as the former increased organic carbon and nitrogen contents in the rhizosphere, whereas the latter reduced their availability. Total soluble protein content and glutamine synthetase activity were greater in the AWMD × DSB treatment than those in the AWCD × NSB treatment. The activities of superoxide dismutase and catalase were higher in the AWMD × DSB treatment compared with the AWCD × NSB treatment, leading to the amelioration of oxidative cell injury, as shown by a lower malonaldehyde level. This study suggested that farmers should implement AWMD irrigation after leaving the straw residues in the field, followed by deep tillage to improve soil quality and mitigate the drought stress cycles of AWD. This approach can improve rice growth and grain quality and alleviate the problems of disposal of straw residues and water scarcity for sustainable rice production.

Key words: antioxidant enzyme activity, wheat straw burial, irrigation regime, nitrogen uptake, Oryza sativa, grain quality, yield

Yousef Alhaj Hamoud, Hiba Shaghaleh, Wang Ruke, Willy Franz Gouertoumbo, Amar Ali Adam hamad, Mohamed Salah Sheteiwy, Wang Zhenchang, Guo Xiangping. Wheat Straw Burial Improves Physiological Traits, Yield and Grain Quality of Rice by Regulating Antioxidant System and Nitrogen Assimilation Enzymes under Alternate Wetting and Drying Irrigation[J]. Rice Science, 2022, 29(5): 473-488.

Figures/Tables 11

References 69

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Treatment	pH	Eh (mV)	TN content (mg/kg)	EOC content (g/kg)	TOC content (g/kg)	DOC content (mg/kg)
AWMD × NSB	5.67 Ca	41.63 Ca	26.57 Ac	2.19 Ab	12.39 Ab	219.8 Ab
AWMD × LSB	5.49 Ca	35.27 Ca	36.37 Ab	5.07 Aa	14.42 Aa	311.6 Ab
AWMD × DSB	5.22 Cb	27.81 Cb	49.97 Aa	6.70 Aa	16.42 Aa	383.9 Aa
AWSD × NSB	7.09 Ba	123.87 Ba	23.13 Bb	2.01 Bb	12.09 Bb	186.1 Bb
AWSD × LSB	6.73 Ba	106.50 Ba	29.87 Bb	4.06 Ba	13.56 Bb	314.2 Ba
AWSD × DSB	6.43 Bb	87.85 Bb	40.70 Ba	5.35 Ba	16.07 Ba	322.0 Ba
AWCD × NSB	7.58 Aa	312.67 Aa	13.20 Cb	1.72 Cc	11.50 Cb	168.6 Cc
AWCD × LSB	7.28 Aa	291.10 Aa	19.87 Cb	2.94 Cb	13.45 Ca	220.4 Cb
AWCD × DSB	7.03 Ab	248.30 Ab	26.33 Ca	3.46 Ca	14.62 Ca	285.6 Ca
AWD irrigation	*	**	*	**	*	*
Straw burial	***	***	**	***	***	*
AWD × Straw	ns	*	**	*	**	***

Treatment	pH	Eh (mV)	TN content (mg/kg)	EOC content (g/kg)	TOC content (g/kg)	DOC content (mg/kg)
AWMD × NSB	5.67 Ca	41.63 Ca	26.57 Ac	2.19 Ab	12.39 Ab	219.8 Ab
AWMD × LSB	5.49 Ca	35.27 Ca	36.37 Ab	5.07 Aa	14.42 Aa	311.6 Ab
AWMD × DSB	5.22 Cb	27.81 Cb	49.97 Aa	6.70 Aa	16.42 Aa	383.9 Aa
AWSD × NSB	7.09 Ba	123.87 Ba	23.13 Bb	2.01 Bb	12.09 Bb	186.1 Bb
AWSD × LSB	6.73 Ba	106.50 Ba	29.87 Bb	4.06 Ba	13.56 Bb	314.2 Ba
AWSD × DSB	6.43 Bb	87.85 Bb	40.70 Ba	5.35 Ba	16.07 Ba	322.0 Ba
AWCD × NSB	7.58 Aa	312.67 Aa	13.20 Cb	1.72 Cc	11.50 Cb	168.6 Cc
AWCD × LSB	7.28 Aa	291.10 Aa	19.87 Cb	2.94 Cb	13.45 Ca	220.4 Cb
AWCD × DSB	7.03 Ab	248.30 Ab	26.33 Ca	3.46 Ca	14.62 Ca	285.6 Ca
AWD irrigation	*	**	*	**	*	*
Straw burial	***	***	**	***	***	*
AWD × Straw	ns	*	**	*	**	***

Treatment	Plant height after a range of growth periods after transplanting (cm)							Number of tillers per m²
Treatment	20 d	30 d	40 d	50 d	70 d	90 d	Harvest	Number of tillers per m²
AWMD × NSB	23.88 Ab	32.00 Ab	36.70 Ab	49.14 Ab	68.23 Ab	66.48 Ab	66.90 Ab	1 312.04 Ac
AWMD × LSB	24.63 Ab	39.63 Ab	40.40 Ab	65.79 Aa	75.30 Aa	74.18 Aa	73.50 Aa	1 600.96 Ab
AWMD × DSB	36.73 Aa	52.30 Aa	53.70 Aa	76.87 Aa	85.70 Aa	82.97 Aa	82.27 Aa	1 889.89 Aa
AWSD × NSB	17.05 Bb	29.60 Bb	28.40 Bb	38.20 Bc	55.47 Bc	53.53 Bc	52.83 Bb	1 156.67 Bc
AWSD × LSB	27.42 Ba	37.00 Ba	42.00 Ba	50.60 Bb	70.87 Bb	67.50 Bb	68.20 Ba	1 345.48 Bb
AWSD × DSB	30.47 Ba	43.77 Ba	47.80 Ba	66.94 Ba	80.95 Ba	80.93 Ba	75.80 Ba	1 723.11 Ba
AWCD × NSB	13.28 Cb	21.53 Ca	24.33 Cb	27.97 Cb	47.73 Cb	46.80 Cb	48.10 Cb	972.33 Cb
AWCD × LSB	19.00 Ca	26.43 Ca	32.80 Ca	37.17 Ca	63.03 Ca	57.53 Ca	56.87 Ca	1 201.07 Ca
AWCD × DSB	20.53 Ca	26.67 Ca	35.20 Ca	40.17 Ca	67.43 Ca	63.12 Ca	60.03 Ca	1 289.89 Ca
AWD irrigation	*	*	**	**	*	*	*	*
Straw burial	**	***	***	***	**	*	**	***
AWD × Straw	**	ns	*	*	**	***	**	**

Treatment	Plant height after a range of growth periods after transplanting (cm)							Number of tillers per m²
Treatment	20 d	30 d	40 d	50 d	70 d	90 d	Harvest	Number of tillers per m²
AWMD × NSB	23.88 Ab	32.00 Ab	36.70 Ab	49.14 Ab	68.23 Ab	66.48 Ab	66.90 Ab	1 312.04 Ac
AWMD × LSB	24.63 Ab	39.63 Ab	40.40 Ab	65.79 Aa	75.30 Aa	74.18 Aa	73.50 Aa	1 600.96 Ab
AWMD × DSB	36.73 Aa	52.30 Aa	53.70 Aa	76.87 Aa	85.70 Aa	82.97 Aa	82.27 Aa	1 889.89 Aa
AWSD × NSB	17.05 Bb	29.60 Bb	28.40 Bb	38.20 Bc	55.47 Bc	53.53 Bc	52.83 Bb	1 156.67 Bc
AWSD × LSB	27.42 Ba	37.00 Ba	42.00 Ba	50.60 Bb	70.87 Bb	67.50 Bb	68.20 Ba	1 345.48 Bb
AWSD × DSB	30.47 Ba	43.77 Ba	47.80 Ba	66.94 Ba	80.95 Ba	80.93 Ba	75.80 Ba	1 723.11 Ba
AWCD × NSB	13.28 Cb	21.53 Ca	24.33 Cb	27.97 Cb	47.73 Cb	46.80 Cb	48.10 Cb	972.33 Cb
AWCD × LSB	19.00 Ca	26.43 Ca	32.80 Ca	37.17 Ca	63.03 Ca	57.53 Ca	56.87 Ca	1 201.07 Ca
AWCD × DSB	20.53 Ca	26.67 Ca	35.20 Ca	40.17 Ca	67.43 Ca	63.12 Ca	60.03 Ca	1 289.89 Ca
AWD irrigation	*	*	**	**	*	*	*	*
Straw burial	**	***	***	***	**	*	**	***
AWD × Straw	**	ns	*	*	**	***	**	**

Treatment	Stem diameter at different parts (mm)			Stem length at different parts (cm)			Total stem length (cm)
Treatment	Upper	Middle	Lower	Upper	Middle	Lower	Total stem length (cm)
AWMD × NSB	3.35 Ab	4.47 Ab	4.68 Ab	15.67 Ab	16.20 Ab	19.03 Ab	50.90 Ab
AWMD × LSB	3.48 Ab	4.78 Ab	4.91 Ab	18.70 Aa	17.10 Aa	22.60 Aa	58.40 Aa
AWMD × DSB	4.28 Aa	5.70 Aa	6.04 Aa	20.73 Aa	18.90 Aa	24.10 Aa	63.73 Aa
AWSD × NSB	3.20 Ba	4.26 Bb	4.48 Bb	14.90 Bb	15.10 Bb	17.94 Bb	47.93 Bb
AWSD × LSB	3.41 Ba	4.60 Ba	4.73 Ba	16.67 Bb	17.23 Ba	19.53 Bb	53.43 Bb
AWSD × DSB	3.77 Ba	5.07 Ba	5.09 Ba	19.97 Ba	17.00 Ba	23.27 Ba	60.23 Ba
AWCD × NSB	2.79 Cb	3.63 Cb	4.18 Ca	11.47 Cc	10.83 Cc	13.00 Cc	36.97 Cb
AWCD × LSB	3.01 Ca	3.86 Cb	4.24 Ca	15.27 Cb	14.73 Cb	17.83 Cb	47.77 Ca
AWCD × DSB	3.06 Ca	4.01 Ca	4.26 Ca	17.44 Ca	17.61 Ca	20.74 Ca	54.43 Ca
AWD irrigation	*	*	*	*	**	**	*
Straw burial	**	*	**	***	***	***	***
AWD × Straw	ns	***	**	ns	*	*	**