Reduced tillage and crop diversification can improve productivity and profitability of rice-based rotations of the Eastern Gangetic Plains

• Published in: Field crops research Vol. 291; p. 108791
• Main Authors: Hoque, Muhammad Arshadul, Gathala, Mahesh K., Timsina, Jagadish, Ziauddin, Md.A.T.M., Hossain, Mosharraf, Krupnik, Timothy J.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 01-02-2023; Elsevier Scientific Pub. Co
• Subjects: Alternate tillage; Calorie and protein yields; Conservation agriculture; Cropping systems diversification; Gross margin; Labor use; Relative yield change; TVC; Conservation agriculture; TAFSSA; REY; Gross margin; R-M; ANOVA; Relative yield change; R-R; Alternate tillage; R-W; CA; ST; Cropping systems diversification; GM; SOC; BARI; R-W-MB; DFAT; SRFSI; GR; BARC; EGP; CSISA; CT; Labor use; AT; SREY; ZT; R-M-MB; Calorie and protein yields; ST, strip tillage; R-W-MB, rice-wheat-mung bean; AT, alternate tillage; R-M-MB, rice-maize-mung bean; CSISA, Cereal Systems Initiative for South Asia; DFAT, Department of Foreign Affairs and Trade; SRFSI, Sustainable and Resilient Farming Systems Intensification; TAFSSA, Transforming Agrifood Systems in South Asia; SOC, soil organic carbon; ANOVA, analysis of variance; CT, conventional tillage; BARI, Bangladesh Agricultural Research Institute; R-M, rice-maize; R-W, rice-wheat; REY, rice equivalent yield; TVC, total variable cost; BARC, Bangladesh Agricultural Research Centre; CA, conservation agriculture; GM, gross margin; ZT, zero tillage; GR, gross return; EGP, Eastern Gangetic Plains; SREY, system rice equivalent yield; R-R, rice-rice
• ISSN: 0378-4290; 1872-6852
• DOI: 10.1016/j.fcr.2022.108791

Intensive rice (Oryza sativa)-based cropping systems in south Asia provide much of the calorie and protein requirements of low to middle-income rural and urban populations. Intensive tillage practices demand more resources, damage soil quality, and reduce crop yields and profit margins. Crop diversification along with conservation agriculture (CA)-based management practices may reduce external input use, improve resource-use efficiency, and increase the productivity and profitability of intensive cropping systems. A field study was conducted on loamy soil in a sub-tropical climate in northern Bangladesh to evaluate the effects of three tillage options and six rice-based cropping sequences on grain, calorie, and protein yields and gross margins (GM) for different crops and cropping sequences. The three tillage options were: (1) conservation agriculture (CA) with all crops in sequences untilled, (2) alternating tillage (AT) with the monsoon season rice crop tilled but winter season crops untilled, and (3) conventional tillage (CT) with all crops in sequences tilled. The six cropping sequences were: rice-rice (R-R), rice-mung bean (Vigna radiata) (R-MB), rice-wheat (Triticum aestivum) (R-W), rice-maize (Zea mays) (R-M), rice-wheat-mung bean (R-W-MB), and rice-maize-mung bean (R-M-MB). Over three years of experimentation, the average monsoon rice yield was 8% lower for CA than CT, but the average winter crops yield was 13% higher for CA than CT. Systems rice equivalent yield (SREY) and systems calorie and protein yields were about 5%, 3% and 6%, respectively, higher under CA than CT; additionally, AT added approximately 1% more to these benefits. The systems productivity gain under CA and AT resulted in higher GM by 16% while reducing the labor and total production cost under CA than CT. The R-M rotation had higher SREY, calorie, protein yields, and GM by 24%, 26%, 66%, and 148%, respectively, than the predominantly practiced R-R rotation. The R-W-MB rotation had the highest SREY (30%) and second highest (118%) GM. Considering the combined effect of tillage and cropping system, CA with R-M rotation showed superior performance in terms of SREY, protein yield, and GM. The distribution of labor use and GM across rotations was grouped into four categories: R-W in low-low (low labor use and low GM), R-M in low-high (low labor use and high GM), R-W-MB and R-M-MB in high-high (high labor use and high GM) and R-R and R-MB in high-low (high labor use and low GM). In conclusion, CA performed better than CT in different winter crops and cropping systems but not in monsoon rice. Our results demonstrate the multiple benefits of partial and full CA-based tillage practices employed with appropriate crop diversification to achieve sustainable food security with greater calorie and protein intake while maximizing farm profitability of intensive rice-based rotational systems.
•Rice-maize (R-M) outperformed over all other rice-based cropping systems considering yields and profits.•Conservation agriculture (CA) and alternate tillage (AT) outperformed than conventional tillage (CT).•R-M and rice-wheat-mungbean systems are more beneficial when layered with CA and AT.•Rice-rice system is more labor intensive and less profitable than other systems.•CA is good for winter crops and for cropping systems but not for rice but AT can be viable alternative option.