Can Southeast Asia continue to be a major rice bowl?

Abstract Southeast Asia is a major rice-producing region, with high level of internal consumption and accounting for 40% of global rice exports. Limited land resources, climate change, and yield stagnation during recent years have once again raised concerns about the capacity of the region to meet the growing demand for rice and remain as a large net exporter. Here we use a modelling approach to map rice yield gaps and assess production potential and net exports by 2040. We find that the average yield gap represents 48% of the yield potential estimate for the region. Exploitable yield gaps are relatively large in Cambodia, Myanmar, Philippines, and Thailand, but comparably smaller in Indonesia and Vietnam. Continuation of current yield trends will not allow Indonesia and Philippines to meet their domestic rice demand. In contrast, closing the exploitable yield gap would allow all countries to achieve rice self-sufficiency, with an aggregated annual rice surplus of 100 million tons available for export. Our study provides insights for increasing regional production on existing cropland by narrowing existing yield gaps.

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Spatial frameworks for robust estimation of yield gaps

Nature Food ◽

10.1038/s43016-021-00365-y ◽

2021 ◽

Author(s):

Juan I. Rattalino Edreira ◽

José F. Andrade ◽

Kenneth G. Cassman ◽

Martin K. van Ittersum ◽

Marloes P. van Loon ◽

...

Keyword(s):

Food Security ◽

Crop Production ◽

Spatial Scales ◽

Sub Saharan Africa ◽

Yield Potential ◽

Top Down ◽

Yield Gap ◽

Bottom Up ◽

Improvement Project ◽

Yield Gaps

AbstractFood security interventions and policies need reliable estimates of crop production and the scope to enhance production on existing cropland. Here we assess the performance of two widely used ‘top-down’ gridded frameworks (Global Agro-ecological Zones and Agricultural Model Intercomparison and Improvement Project) versus an alternative ‘bottom-up’ approach (Global Yield Gap Atlas). The Global Yield Gap Atlas estimates extra production potential locally for a number of sites representing major breadbaskets and then upscales the results to larger spatial scales. We find that estimates from top-down frameworks are alarmingly unlikely, with estimated potential production being lower than current farm production at some locations. The consequences of using these coarse estimates to predict food security are illustrated by an example for sub-Saharan Africa, where using different approaches would lead to different prognoses about future cereal self-sufficiency. Our study shows that foresight about food security and associated agriculture research priority setting based on yield potential and yield gaps derived from top-down approaches are subject to a high degree of uncertainty and would benefit from incorporating estimates from bottom-up approaches.

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Wheat yield gaps across smallholder farming systems in Ethiopia

Agronomy for Sustainable Development ◽

10.1007/s13593-020-00654-z ◽

2021 ◽

Vol 41 (1) ◽

Author(s):

João Vasco Silva ◽

Pytrik Reidsma ◽

Frédéric Baudron ◽

Moti Jaleta ◽

Kindie Tesfaye ◽

...

Keyword(s):

Stochastic Frontier Analysis ◽

Stochastic Frontier ◽

Wheat Yield ◽

Farming Systems ◽

Smallholder Farming ◽

Yield Gap ◽

Frontier Analysis ◽

Ecological Zones ◽

Relative Contribution ◽

Yield Gaps

AbstractWheat yields in Ethiopia need to increase considerably to reduce import dependency and keep up with the expected increase in population and dietary changes. Despite the yield progress observed in recent years, wheat yield gaps remain large. Here, we decompose wheat yield gaps in Ethiopia into efficiency, resource, and technology yield gaps and relate those yield gaps to broader farm(ing) systems aspects. To do so, stochastic frontier analysis was applied to a nationally representative panel dataset covering the Meher seasons of 2009 and 2013 and crop modelling was used to simulate the water-limited yield (Yw) in the same years. Farming systems analysis was conducted to describe crop area shares and the availability of land, labour, and capital in contrasting administrative zones. Wheat yield in farmers’ fields averaged 1.9 t ha− 1 corresponding to ca. 20% of Yw. Most of the yield gap was attributed to the technology yield gap (> 50% of Yw) but narrowing efficiency (ca. 10% of Yw) and resource yield gaps (ca. 15% of Yw) with current technologies can nearly double actual yields and contribute to achieve wheat self-sufficiency in Ethiopia. There were small differences in the relative contribution of the intermediate yield gaps to the overall yield gap across agro-ecological zones, administrative zones, and farming systems. At farm level, oxen ownership was positively associated with the wheat cultivated area in zones with relatively large cultivated areas per household (West Arsi and North Showa) while no relationship was found between oxen ownership and the amount of inputs used per hectare of wheat in the zones studied. This is the first thorough yield gap decomposition for wheat in Ethiopia and our results suggest government policies aiming to increase wheat production should prioritise accessibility and affordability of inputs and dissemination of technologies that allow for precise use of these inputs.

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Methodology of Analyzing Maize Density Loss in Smallholder’s Fields and Potential Optimize Approach

Agriculture ◽

10.3390/agriculture11060480 ◽

2021 ◽

Vol 11 (6) ◽

pp. 480

Author(s):

Zhichao An ◽

Chong Wang ◽

Xiaoqiang Jiao ◽

Zhongliang Kong ◽

Wei Jiang ◽

...

Keyword(s):

Decision Making ◽

Food Security ◽

Zea Mays L ◽

Plant Density ◽

Density Difference ◽

Yield Gap ◽

Farmer Decision Making ◽

Yield Gaps ◽

Farmer Survey ◽

Experimental Plots

Increasing plant density is a key measure to close the maize (Zea mays L.) yield gap and ensure food security. However, there is a large plant density difference in the fields sown by agronomists and smallholders. The primary cause of this phenomenon is the lack of an effective methodology to systematically analyze the density loss. To identify the plant density loss processes from experimental plots to smallholder fields, a research methodology was developed in this study involving a farmer survey and measurements in a smallholder field. The results showed that the sowing density difference caused by farmer decision-making and plant density losses caused by mechanical and agronomic factors explained 15.5%, 5.5% and 6.8% of the plant density difference, respectively. Changing smallholder attitudes toward the value of increasing the plant density could help reduce this density loss and increase farm yields by 12.3%. Therefore, this methodology was effective for analyzing the plant density loss, and to clarify the primary causes of sowing density differences and plant density loss. Additionally, it was beneficial to identify the priorities and stakeholders who share responsibility for reducing the density loss. The methodology has wide applicability to address the sowing density differences and plant density loss in other areas to narrow crop yield gaps and ensure food security.

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The soybean yield gap in Brazil – magnitude, causes and possible solutions for sustainable production

The Journal of Agricultural Science ◽

10.1017/s0021859615000313 ◽

2015 ◽

Vol 153 (8) ◽

pp. 1394-1411 ◽

Cited By ~ 61

Author(s):

P. C. SENTELHAS ◽

R. BATTISTI ◽

G. M. S. CÂMARA ◽

J. R. B. FARIAS ◽

A. C. HAMPF ◽

...

Keyword(s):

Water Deficit ◽

Precision Agriculture ◽

Crop Management ◽

Sustainable Production ◽

Biodiesel Production ◽

Yield Gap ◽

Soybean Yield ◽

South Central ◽

Crop Simulation ◽

Yield Gaps

SUMMARYBrazil is one of the most important soybean producers in the world. Soybean is a very important crop for the country as it is used for several purposes, from food to biodiesel production. The levels of soybean yield in the different growing regions of the country vary substantially, which results in yield gaps of considerable magnitude. The present study aimed to investigate the soybean yield gaps in Brazil, their magnitude and causes, as well as possible solutions for a more sustainable production. The concepts of yield gaps were reviewed and their values for the soybean crop determined in 15 locations across Brazil. Yield gaps were determined using potential and attainable yields, estimated by a crop simulation model for the main maturity groups of each region, as well as the average actual famers’ yield, obtained from national surveys provided by the Brazilian Government for a period of 32 years (1980–2011). The results showed that the main part of the yield gap was caused by water deficit, followed by sub-optimal crop management. The highest yield gaps caused by water deficit were observed mainly in the south of Brazil, with gaps higher than 1600 kg/ha, whereas the lowest were observed in Tapurah, Jataí, Santana do Araguaia and Uberaba, between 500 and 1050 kg/ha. The yield gaps caused by crop management were mainly concentrated in South-central Brazil. In the soybean locations in the mid-west, north and north-east regions, the yield gap caused by crop management was <500 kg/ha. When evaluating the integrated effects of water deficit and crop management on soybean yield gaps, special attention should be given to Southern Brazil, which has total yield gaps >2000 kg/ha. For reducing the present soybean yield gaps observed in Brazil, several solutions should be adopted by growers, which can be summarized as irrigation, crop rotation and precision agriculture. Improved dissemination of agricultural knowledge and the use of crop simulation models as a tool for improving crop management could further contribute to reduce the Brazilian soybean yield gap.

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Development of a new maize hybrid for the Ecuadorian lowland

Agronomía Colombiana ◽

10.15446/agron.colomb.v36n2.68782 ◽

2018 ◽

Vol 36 (2) ◽

pp. 174-179

Author(s):

Ricardo Limongi-Andrade ◽

Daniel Alarcón-Cobeña ◽

Eddie Zambrano-Zambrano ◽

Marlon Caicedo ◽

Paúl Villavicencio-Linzan ◽

...

Keyword(s):

Zea Mays L ◽

Regression Coefficient ◽

Yield Potential ◽

Curvularia Lunata ◽

Exserohilum Turcicum ◽

Maize Production ◽

Maize Hybrid ◽

Puccinia Sorghi ◽

Feed Production ◽

Self Sufficiency

Yellow maize (Zea mays L. var. indurata) is mainly produced in the Ecuadorian lowlands (less than 1,200 m a.s.l.), primarily for feed production. Although Ecuador has recently increased maize production, new genotypes are needed for self-sufficiency and in order to avoid costly imports. Maize is sown mostly from December to January during the rainy season. However, the irregularity of rainfall has become a constraint on production. “INIAP H-603 Superior” is a new single-cross maize hybrid developed for the Ecuadorian lowlands with improved yields, which could contribute to domestic food security. The new hybrid had an average yield of 8.48 t ha-1 with outstanding performance under the rainfall, sustained moisture, and irrigation conditions, outperforming the commercial hybrids INIAP H-602, DEKALB-7088 and INIAP H-553. Additionally, the new hybrid showed tolerance to the principal foliar diseases: leaf blight (Exserohilum turcicum), rust (Puccinia sorghi), and leaf spot (Curvularia lunata), as well as good adaptability and stability, with a regression coefficient (bi) of 0.98 when it was evaluated in 29 locations from 2010 to 2013. The greatest yield potential of the new hybrid (10.82 t ha-1) was obtained with irrigation during the dry season.

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PELUANG PENINGKATAN PRODUKSI PADI PADA DI LAHAN RAWA LEBAK LAMPUNG

Jurnal Penelitian dan Pengembangan Pertanian ◽

10.21082/jp3.v36n1.2017.p13-20 ◽

2017 ◽

Vol 36 (1) ◽

pp. 13

Author(s):

Yulia Pujiharti

Keyword(s):

Integrated Pest Management ◽

Pest Management ◽

Fresh Water ◽

Rice Yield ◽

Fertilizer Application ◽

Rice Production ◽

Land Productivity ◽

Yield Gap ◽

Integrated Crop Management ◽

Self Sufficiency

Opportunity to Increase Rice Production in Fresh Water Swampy Land in LampungThe area of fresh water swampy land in Lampung in 2012 was 55,714 ha with rice productivity of 5.13 t/ha so it is possible to be increased. The article discusses opportunity to increase rice production in fresh water swampy land in Lampung. Increasing rice yield can be done by enhancing cropping index and land productivity, lowering yield gap and decreasing yeld loss. Cropping index in fresh water swampy land can be increased by cultivating rice with surjan system, while rice yield is increased by integrated crop management (ICM) which its components include the use of improved varieties, planting with legowo 2: 1 or 4: 1, fertilizer application according to plant need, water management to prevent rice plant from submerging or drought, and integrated pest management. Rice yield gap is decreased by implementing location specific technologies and intensifying counseling to farmers, while yield loss is lowered by applying integrated pest management and using agricultural tools and machineries in rice farming. These production increases have an impact on the regional and national food availability in an effort to achieve rice self-sufficiency.Keywords: Rice, production, fresh water swampy land, growth source ABSTRAKLuas lahan rawa lebak di Provinsi Lampung pada tahun 2012 mencapai 55.714 ha dengan tingkat produktivitas padi 5,13 t/ha sehingga masih berpeluang ditingkatkan. Tulisan ini membahas peluang peningkatan produksi padi di lahan rawa lebak di Lampung. Peningkatan produksi dapat dilakukan melalui peningkatan indeks pertanaman (IP) dan produktivitas lahan, mengurangi senjang hasil, dan menurunkan kehilangan hasil. Indeks pertanaman di lahan rawa lebak dapat ditingkatkan dengan menerapkan sistem surjan. Sementara produktivitas ditingkatkan melalui pengelolaan tanaman terpadu (PTT) dengan komponen teknologinya antara lain penggunaan varietas unggul baru, cara tanam legowo 2:1 atau 4:1, pemberian hara sesuai kebutuhan tanaman, pengelolaan tata air sehingga tanaman padi terhindar dari terendam atau kekeringan, serta pengelolaan hama dan penyakit secara terpadu. Penurunan senjang hasil dapat dilakukan dengan menerapkan teknologi spesifik lokasi dan mengintensifkan penyuluhan ke petani. Sementara kehilangan hasil dapat dikurangi melalui penerapan pengelolaan hama dan penyakit secara terpadu dan penggunaan alat dan mesin pertanian pada kegiatan usaha tani. Peningkatan produksi ini akan berdampak pada peningkatan ketersediaan pangan daerah dan nasional dalam upaya mencapai swasembada beras.Kata Kunci: Padi, produksi, rawa lebak, sumber pertumbuhan

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Using Motivational Modelling With an App Designed to Increase Student Performance and Retention

Early Warning Systems and Targeted Interventions for Student Success in Online Courses - Advances in Educational Technologies and Instructional Design ◽

10.4018/978-1-7998-5074-8.ch008 ◽

2020 ◽

pp. 161-176

Author(s):

Leon Sterling ◽

Sonja Pedell ◽

Grainne Oates

Keyword(s):

Student Performance ◽

Mobile Learning ◽

Design And Development ◽

Software Applications ◽

Emotional Factors ◽

Learning Platform ◽

High Level ◽

Modelling Approach

Quitch is software designed to increase student performance and retention. It is a content-neutral, gamified mobile learning platform used across many disciplines, including accounting, chemistry, and engineering. The aim of Quitch is to ensure students feel engaged with their learning. Motivational modelling is a high-level approach to understand the purpose of a system. It is novel in its incorporation of emotional factors. This chapter discusses how the authors applied motivational modelling to Quitch to explain its purpose and potential. The chapter then more generally discusses how their modelling approach can help with the design and development of new software applications especially in the education space.

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Forage yield gap analysis for tall fescue pastures in Argentina: A modelling approach

Grass and Forage Science ◽

10.1111/gfs.12508 ◽

2020 ◽

Author(s):

Juan R. Insua ◽

Claudio F. Machado ◽

Sergio C. Garcia ◽

Germán D. Berone

Keyword(s):

Tall Fescue ◽

Gap Analysis ◽

Forage Yield ◽

Yield Gap ◽

Yield Gap Analysis ◽

Modelling Approach

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A volume integral approach for the modelling and design of HTS coils

COMPEL The International Journal for Computation and Mathematics in Electrical and Electronic Engineering ◽

10.1108/compel-10-2018-0392 ◽

2019 ◽

Vol 38 (4) ◽

pp. 1133-1140 ◽

Cited By ~ 3

Author(s):

Yazid Statra ◽

Hocine Menana ◽

Lamia Belguerras ◽

Bruno Douine

Keyword(s):

Power Law ◽

Strong Dependence ◽

Superconducting Devices ◽

Electromagnetic Properties ◽

Integral Approach ◽

Volume Integral ◽

Content Type ◽

High Level ◽

Modelling Approach

Purpose The purpose of this paper is to develop a rapid and realistic modelling approach for the design and characterization of high temperature superconducting (HTS) coils and windings carrying DC currents. Indeed, the strong dependence of the electromagnetic properties of such materials on the magnetic field makes the design and characterization of HTS systems a delicate operation where local quantities have to be evaluated. Design/methodology/approach A volume integral modelling approach has been developed taking into account the electric nonlinearity of the HTS material which is represented by power law. The variations of the characteristic quantities of the HTS (critical current density and power law exponent) with the magnetic flux density are also taken into account by using Kim’s law. The volume integral modelling allows to model only the active parts of the system and thus to overcome the difficulties linked to the multiscale dimensions. Findings The model has been tested in a case study in which simulation results were compared to measurements and to finite element analysis. A good agreement was found which validates the model as a rapid and efficient tool for HTS coils and windings design and modelling. Practical implications HTS coils are important elements of emerging superconducting devices which require a high level of reliability, such as generators or motors. The proposed approach is interesting to speed up the design and optimization procedures of such systems. Originality/value Advanced structures of the basic elements have been used in the volume integral modelling, which results in a considerable gain in computation time and in memory-space saving while keeping a high level of precision and realism of the modelling, which has been verified experimentally.

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Diagnosing the Climatic and Agronomic Dimensions of Rain-Fed Oat Yield Gaps and Their Restrictions in North and Northeast China

Sustainability ◽

10.3390/su11072104 ◽

2019 ◽

Vol 11 (7) ◽

pp. 2104 ◽

Cited By ~ 1

Author(s):

Chong Wang ◽

Jiangang Liu ◽

Shuo Li ◽

Ting Zhang ◽

Xiaoyu Shi ◽

...

Keyword(s):

Northeast China ◽

Crop Production ◽

Crop Yields ◽

Climatic Conditions ◽

Planting Density ◽

Limiting Factors ◽

High Yield ◽

Yield Gap ◽

Potential Yield ◽

Yield Gaps

Confronted with the great challenges of globally growing populations and food shortages, society must achieve future food security by increasing grain output and narrowing the gap between potential yields and farmers’ actual yields. This study attempts to diagnose the climatic and agronomic dimensions of oat yield gaps and further to explore their restrictions. A conceptual framework was put forward to analyze the different dimensions of yield gaps and their limiting factors. We quantified the potential yield (Yp), attainable yield (Yt), experimental yield (Ye), and farmers’ actual yield (Ya) of oat, and evaluated three levels of yield gaps in a rain-fed cropping system in North and Northeast China (NC and NEC, respectively). The results showed that there were great differences in the spatial distributions of the four kinds of yields and three yield gaps. The average yield gap between Yt and Ye (YG-II) was greater than the yield gap between Yp and Yt (YG-I). The yield gap between Ye and Ya (YG-III) was the largest among the three yield gaps at most sites, which indicated that farmers have great potential to increase their crop yields. Due to non-controllable climatic conditions (e.g., light and temperature) for obtaining Yp, reducing YG-I is extremely difficult. Although YG-II could be narrowed through enriching soil nutrients, it is not easy to improve soil quality in the short term. In contrast, narrowing YG-III is the most feasible for farmers by means of introducing high-yield crop varieties and optimizing agronomic managements (e.g., properly adjusting sowing dates and planting density). This study figured out various dimensions of yield gaps and investigated their limiting factors, which should be helpful to increase farmers’ yields and regional crop production, as long as these restrictions are well addressed.

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