Methane emissions from double-rice cropping system under conventional and no tillage in southeast China

AbstractSimplified cultivation methods for rice production offer considerable social, economic, and environmental benefits. However, limited information is available on yield components of rice grown using simplified cultivation methods in a rice-ratoon rice cropping system. A field experiment using two hybrid and two inbred rice cultivars was conducted to compare four cultivation methods (conventional tillage and transplanting, CTTP; conventional tillage and direct seeding, CTDS; no-tillage and transplanting, NTTP; no-tillage and direct seeding, NTDS) in a rice-ratoon rice system from 2017 to 2020. Main season yields for CTDS and NTDS were higher than for CTTP by 6.1% and 2.8%, respectively; whereas ratoon season yields for CTDS and NTDS were equal to or higher than for CTTP. Annual grain yields for CTDS and NTDS were higher than for CTTP by 4.4% and 3.2%, respectively. The higher CTDS and NTDS yields were associated with higher panicle numbers per m2 and biomass production. Rice hybrids had higher yields than inbred cultivars by 15.8–19.3% for main season and by 15.6–19.4% for ratoon season, which was attributed to long growth duration, high grain weight and biomass production. Our results suggest that CTTP can be replaced by CTDS and NTDS to maintain high grain yields and save labor costs. Developing cultivars with high grain weight could be a feasible approach to achieve high rice yields in the rice-ratoon rice cropping system in southwest China.

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Long-Term Green Manure Rotations Improve Soil Biochemical Properties, Yield Sustainability and Nutrient Balances in Acidic Paddy Soil under a Rice-Based Cropping System

Agronomy ◽

10.3390/agronomy9120780 ◽

2019 ◽

Vol 9 (12) ◽

pp. 780

Author(s):

Muhammad Qaswar ◽

Jing Huang ◽

Waqas Ahmed ◽

Dongchu Li ◽

Shujun Liu ◽

...

Keyword(s):

Grain Yield ◽

Green Manure ◽

Cropping Systems ◽

Cropping System ◽

Biochemical Properties ◽

Control Treatment ◽

Yield Sustainability ◽

Double Rice ◽

Winter Fallow

Cultivation of green manure (GM) crops in intensive cropping systems is important for enhancing crop productivity through soil quality improvement. We investigated yield sustainability, nutrient stocks, nutrient balances and enzyme activities affected by different long-term (1982–2016) green manure rotations in acidic paddy soil in a double-rice cropping system. We selected four treatments from a long-term experiment, including (1) rice-rice-winter fallow as a control treatment (R-R-F), (2) rice-rice-milkvetch (R-R-M), (3) rice-rice-rapeseed (R-R-R), and (4) rice-rice-ryegrass (R-R-G). The results showed that different GM rotations increased grain yield and the sustainable yield index compared with those of the R-R-F treatment. Compared with those of R-R-F, the average grain yield of early rice in R-R-M, R-R-R, and R-R-G increased by 45%, 29%, and 27%, respectively and that of late rice increased by 46%, 28%, and 26%, respectively. Over the years, grain yield increased in all treatments except R-R-F. Green manure also improved the soil chemical properties (SOM and total and available N and P), except soil pH, compared to those of the control treatment. During the 1983–1990 cultivation period, the soil pH of the R-R-M treatment was lower than that of the R-R-F treatment. The addition of green manure did not mitigate the soil acidification caused by the use of inorganic fertilizers. The soil organic matter (SOM), total nitrogen (TN) and total phosphorus (TP) contents and stocks of C, N and P increased over the years. Furthermore, GM significantly increased phosphatase and urease activities and decreased the apparent N and P balances compared with those in the winter fallow treatment. Variance partitioning analysis revealed that soil properties, cropping systems, and climatic factors significantly influenced annual grain yield. Aggregated boosted tree (ABT) analysis quantified the relative influences of the different soil properties on annual grain yield and showed that the relative influences of TN content, SOM, pH, and TP content on annual crop yield were 27.8%, 25.7%, 22.9%, and 20.7%, respectively. In conclusion, GM rotation is beneficial for sustaining high crop yields by improving soil biochemical properties and reducing N and P balances in acidic soil under double- rice cropping systems.

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Bioactive Properties of Fruits and Leafy Vegetables Managed with Integrated, Organic, and Organic No-Tillage Practices in the Mediterranean Area: A Two-Year Rotation Experiment

Agronomy ◽

10.3390/agronomy10060841 ◽

2020 ◽

Vol 10 (6) ◽

pp. 841 ◽

Cited By ~ 2

Author(s):

Costanza Ceccanti ◽

Marco Landi ◽

Daniele Antichi ◽

Lucia Guidi ◽

Luigi Manfrini ◽

...

Keyword(s):

Bioactive Compounds ◽

Environmental Sustainability ◽

Management Practices ◽

Cropping Systems ◽

Cropping System ◽

Conservation Agriculture ◽

Leafy Vegetables ◽

No Tillage ◽

Cash Crops ◽

Starting Point

The sustainability of current farming systems has been questioned in the last decades, especially in terms of the environmental impact and mitigation of global warming. Also, the organic sector, which is supposed to impact less on the environment than other more intensive systems, is looking for innovative solutions to improve its environmental sustainability. Promisingly, the integration of organic management practices with conservation agriculture techniques may help to increase environmental sustainability of food production. However, little is known about the possible impact of conservation agriculture on the content of bioactive compounds in cash crops. For this reason, a two-year rotation experiment used 7 cash crops (4 leafy vegetables and 3 fruit crops) to compare integrated (INT), organic farming (ORG), and organic no-tillage (ORG+) systems to evaluate the possible influence of cropping systems on the nutritional/nutraceutical values of the obtained fruits and leafy vegetables. The results pointed out specific responses based on the species as well as the year of cultivation. However, cultivation with the ORG+ cropping system resulted in effective obtainment of fruits and vegetables with higher levels of bioactive compounds in several cases (11 out 16 observations). The ORG+ cropping system results are particularly promising for leafy vegetable cultivation, especially when ORG+ is carried out on a multi-year basis. Aware that the obtained data should be consolidated with longer-term experiments, we conclude that this dataset may represent a good starting point to support conservation agriculture systems as a possible sustainable strategy to obtain products with higher levels of bioactive compounds.

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Medium-term effects of different types of N fertilizer on yield, apparent N recovery, and soil chemical properties of a double rice cropping system

Field Crops Research ◽

10.1016/j.fcr.2019.02.012 ◽

2019 ◽

Vol 234 ◽

pp. 87-94 ◽

Cited By ~ 7

Author(s):

Wenhai Mi ◽

Qiang Gao ◽

Siqi Xia ◽

Haitao Zhao ◽

Lianghuan Wu ◽

...

Keyword(s):

Chemical Properties ◽

Cropping System ◽

N Fertilizer ◽

Soil Chemical Properties ◽

N Recovery ◽

Medium Term ◽

Different Types ◽

Apparent N Recovery ◽

Double Rice

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Substitution of Inorganic Nitrogen Fertilizer with Green Manure (GM) Increased Yield Stability by Improving C Input and Nitrogen Recovery Efficiency in Rice Based Cropping System

Agronomy ◽

10.3390/agronomy9100609 ◽

2019 ◽

Vol 9 (10) ◽

pp. 609 ◽

Cited By ~ 3

Author(s):

Qaswar ◽

Jing ◽

Ahmed ◽

Shujun ◽

Dongchu ◽

...

Keyword(s):

Crop Yield ◽

Green Manure ◽

Inorganic Nitrogen ◽

Cropping System ◽

N Fertilization ◽

Yield Stability ◽

N Fertilizer ◽

Yield Variability ◽

Variability Index ◽

Double Rice

A long-term field experiment was carried out (since 2008) for evaluating the effects of different substitution rates of inorganic nitrogen (N) fertilizer by green manure (GM) on yield stability and N balance under double rice cropping system. Treatments included, (1) N0 (no N fertilizer and no green manure); (2) N100 (recommended rate of N fertilizer and no green manure); (3) N100-M (recommended rate of N fertilizer and green manure); (4) N80-M (80% of recommended N fertilizer and green manure); (5) N60-M (60% of recommended N fertilizer and green manure); and (6) M (green manure without N fertilization). Results showed that, among all treatments, annual crop yield under N80-M treatment was highest. Crop yield did not show significant differences between N100-M and N80-M treatments. Substitution of different N fertilizer rates by GM reduced the yield variability index. Compared to the N0 treatment, yield variability index of early rice under N100-M, N80-M, and N60-M treatments was decreased by 11%, 26%, and 36%, respectively. Compared to the N0 treatment, yield variability index of late rice was decreased by 12%, 38%, 49%, 47%, and 24% under the N100, N100-M, N80-M, N60-M, and M treatments, respectively. During period of 2009–2013 and 2014–2018, nitrogen recovery efficiency (NRE) was highest under N80-M treatment and N balance was highest under N100 treatment. NRE of all treatments with GM was increased over the time from 2009–2013 to 2014–2018. All treatments with GM showed increasing trend of SOC over the years. Substitution of N fertilizer by GM also increased C inputs and soil C:N ratio compared to the N100 and N0 treatments. Boosted regression model indicated that C input, N uptake and AN were most influencing factors of crop yield. Thus, we concluded that N fertilization rates should be reduced by 20% under GM rotation to attain high yield stability of double rice cropping system through increasing NRE and C inputs.

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