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

2015 ◽  
Vol 153 (8) ◽  
pp. 1394-1411 ◽  
Author(s):  
P. C. SENTELHAS ◽  
R. BATTISTI ◽  
G. M. S. CÂMARA ◽  
J. R. B. FARIAS ◽  
A. C. HAMPF ◽  
...  

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.

Author(s):  
Paulo J. O. P. Souza ◽  
Vivian D. da S. Farias ◽  
João V. N. Pinto ◽  
Hildo G. G. C. Nunes ◽  
Everaldo B. de Souza ◽  
...  

ABSTRACT The cowpea bean presents low productivity in the Pará state, Brazil, due to low soil fertility and climatic adversity, mainly water deficiency. The aim of this study was to evaluate the yield gap of cowpea bean in northeast of Para state in response to water deficit during its reproductive phase. The experiment was carried out in Castanhal, PA, Brazil, during 2015 and 2016. A randomized block design with six repetitions and four treatments was used; where T1 consisted of 100% replacement of the crop evapotranspiration (ETc), T2 to 50%, T3 to 25% and T4 without irrigation, in the reproductive phase. The yield was determined at R9 stage. The simulations with the SARRAZON model were carried out with different sowing dates. The total deficiencies in the reproductive phase were spatialized considering the 30 locations in order to assess the temporal and spatial seasonality of water availability and the sowing period in the study region. The cowpea bean was sensitive to soil water availability with considerable reductions in productivity due to the increase in water deficit compared to the treatment T1 (100% ETc). When water deficits reached more than 47 mm, there were yield gaps over 20%. According to the spatial variability of simulated water deficiency, the sowing of cowpea bean in regions located above 2° latitude may extend until June 20 without showing high yield gaps.


Agronomy ◽  
2020 ◽  
Vol 10 (8) ◽  
pp. 1135
Author(s):  
Julius Kwesiga ◽  
Kristina Grotelüschen ◽  
Kalimuthu Senthilkumar ◽  
Daniel Neuhoff ◽  
Thomas F. Döring ◽  
...  

To meet the growing rice demand in Africa, gaps between actual and attainable yields have to be reduced. In Tanzania, this particularly concerns smallholder rain-fed production systems in the floodplains. After quantifying the existing yield gaps, key contributing factors need to be analyzed to improve site-specific management. Field experiments were conducted for three years and in three pedo-hydrological environments (fringe, middle, and center positions) of the Kilombero floodplain to evaluate: (1) The grain yield under farmers’ management (actual yield), (2) yield with the best-recommended management (attainable yield), and (3) the non-limited yield simulated by the APSIM model (potential yield). In the field, we additionally assessed incremental effects of (1) field bunding and soil levelling, (2 and 3) additionally applying of 60 kg N ha−1, as urea or as farmyard manure (FYM), and (4 and 5) incorporating in-situ-grown leguminous green manures. Attainable yields were determined with mineral N application at 120 kg ha−1, additional PK fertilizer and supplemental irrigation. On average across years and positions, the potential, the attainable, and farmers’ actual yields were 11.5, 8.5, and 2.8 t ha−1 indicating a high total yield gap. About 16–38%, 11–20%, and 28–42% of this gap could be attributed to non-controllable yield-reducing (i.e., pest and diseases), yield-limiting (i.e., water and nutrient deficiencies), and yield-defining factors (i.e., poor soil and crop management), respectively. Results indicate a closure of the exploitable yield gap (differences between attainable and farmers’ actual yields) by up to 6.5 t ha−1 (nearly 60% of the potential yield). This exploitable yield gap was larger in 2016 than in 2017. Also, the gap was larger in the water-limited fringe and middle than in the frequently submerged center positions. Simple field bunds combined with land levelling could close 15–35% of the exploitable yield gap, depending on field positions and year. FYM or green manures were less effective than mineral N; however, in 2017 and in the wetter middle and center positions, they reduced the yield gap by >50%. We conclude that yield gaps in rainfed rice in Kilombero floodplain are large, but that a site- and system-specific adaptation of crop management can close much of the exploitable yield gap and increase grain yields by 0.7–4.8 t ha−1. Similar benefits may be obtained in other hydrologically variable floodplain environments of the region and beyond.


2015 ◽  
Vol 52 (4) ◽  
pp. 493-517 ◽  
Author(s):  
MEZEGEBU GETNET ◽  
MARTIN VAN ITTERSUM ◽  
HUIB HENGSDIJK ◽  
KATRIEN DESCHEEMAEKER

SUMMARYIn the Central Rift Valley (CRV) of Ethiopia, low productive cereal systems and a declining resource base call for options to increase crop productivity and improve resource use efficiency to meet the growing demand of food. We compiled and analysed a large amount of data from farmers’ fields (>10,000) and experimental data across the CRV from 2004–2009 to quantify yield gaps (Yg) between actual (average and best performing farmers) and experimental (water-limited potential (Yw)) yields of maize and wheat in homogenous farming zones (HFZs). Resource use efficiencies (nutrients and water) of maize and wheat were also analysed to assess spatial variation and scope for improvements. The average (2004–2009) yield gap of maize and wheat in the CRV ranged between 4.2 t ha−1 and 9.2 t ha−1, and 2.5 t ha−1 and 4.7 t ha−1, respectively, across farming zones. The yield gap was lowest in the Central lowlands, where Yw was also lowest, i.e. 6.5 t ha−1 for maize and 4.4 t ha−1 for wheat, compared with Yw in the Eastern highlands (11 t ha−1 for maize and 6.7 t ha−1 for wheat) and Western highlands (10.8 t ha−1 for maize and 5.7 t ha−1 for wheat). The actual nitrogen (N) and phosphorus (P) application in farmers’ fields was low, as about 46% of maize and 27% of wheat fields did not receive fertilizers, while the average applied mineral fertilizer rates across all farmers (2.6–16.5 kg N ha−1 and 2.2–17.3 kg P ha−1 across HFZs and crops) were far below the recommended rate. On average, the best performing farmers applied 8–20 kg N ha−1 and 5–21 kg P ha−1 ranging across HFZs and crops. Increasing N application to recommended rates had only a small effect on narrowing the yield gap under current farmers’ management. Therefore, the yield gap closure strongly depends on improving other aspects of crop management while paying attention to the interaction with nutrient management. Since rain water use efficiency (seasonal rainfall) of water-limited yields was 12–17.3 kg mm−1 for maize and 7.4–10.6 kg mm−1 for wheat and much higher than that of actual yields (2.7–4.3 kg mm−1 for maize and 2.3–3.5 kg mm−1 for wheat), improving the input use and crop management can increase water use efficiency. A large set of experimental and survey data enabled us to gain insight in the spatial and temporal variation in yield gaps and input rates and in differences between average and the best performing farmers.


2021 ◽  
Vol 41 (1) ◽  
Author(s):  
João Vasco Silva ◽  
Pytrik Reidsma ◽  
Frédéric Baudron ◽  
Moti Jaleta ◽  
Kindie Tesfaye ◽  
...  

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.


Agriculture ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 480
Author(s):  
Zhichao An ◽  
Chong Wang ◽  
Xiaoqiang Jiao ◽  
Zhongliang Kong ◽  
Wei Jiang ◽  
...  

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.


2020 ◽  
Vol 15 (4) ◽  
pp. 365-371
Author(s):  
Deepayan Debnath ◽  
◽  
Suresh Babu ◽  

There is a significant soybean yield gap in sub-Saharan African (SSA) countries. Sustainable intensification of the agricultural sector to reduce such a yield gap is important. Increasing soybean productivity can meet the growing demand for food and feed when complemented with higher soy meal demand by the local livestock industry. This study performs an ex-ante economic analysis to determine the effect of higher soybean production on trade and land use within SSA countries. We find that increasing soybean yield by 50% can increase the total returns from soybean production by 186 million LC (local currency) in Ethiopia and 36 billion LC in Nigeria. We show that soybean yield growth alone is enough to boost soy oil production, as the crushing of the beans produces 18% oil and 79% meal. While increasing productivity may lead to freeing land to produce high-valued cash crops, investors will be reluctant to invest in the crushing facilities in the absence of soy meal demand by the livestock industry. Therefore, policymakers need to establish collaboration between development organisations, private companies, farmers and researchers to achieve this transformation and thereby raise agricultural productivity.


2020 ◽  
Vol 71 (5) ◽  
pp. 445 ◽  
Author(s):  
Rogério de Souza Nóia Júnior ◽  
Paulo Cesar Sentelhas

The succession of main-season soybean (Glycine max (L.) Merr.) with off-season maize (Zea mays L.) is an important Brazilian agricultural system contributing to increased grain production without the need for crop land expansion. Yield-gap studies that identify the main factors threatening these crops are pivotal to increasing food security in Brazil and globally. Therefore, the aim of the present study was to determine, for the soybean–off-season-maize succession, the magnitude of the grain and revenue yield gap (YG) caused by water deficit (YGW) and suboptimal crop management (YGM), and to propose strategies for closing these gaps in different Brazilian regions. The ensemble of three previously calibrated and validated models (FAO-AZM, DSSAT and APSIM) was used to estimate yields of soybean and off-season maize for 28 locations in 12 states for a period of 34 years (1980–2013). Water deficit is the biggest problem for soybean and off-season maize crops in the regions of Cocos (state of Bahia), Buritis (Minas Gerais) and Formosa (Goiás), where the YGW accounted for ~70% of total YG. The YGM revealed that locations in the central region of Brazil, mainly in the state of Mato Grosso, presented an opportunity to increase yields of soybean and off-season maize, on average, by 927.5 and 909.6 5 kg ha–1, respectively. For soybean, YGM was the main cause of total YG in Brazil, accounting for 51.8%, whereas for maize, YGW corresponded to 53.8% of the total YG. Our results also showed that the choice of the best sowing date can contribute to reducing soybean YGW by 34–54% and off-season maize YGW by 66–89%.


2019 ◽  
Vol 11 (7) ◽  
pp. 2104 ◽  
Author(s):  
Chong Wang ◽  
Jiangang Liu ◽  
Shuo Li ◽  
Ting Zhang ◽  
Xiaoyu Shi ◽  
...  

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.


1970 ◽  
Vol 36 (3) ◽  
pp. 469-476 ◽  
Author(s):  
Mohammad H Mondal

The concept of yield gaps originated from the studies conducted by IRRI in the seventies. The yield gap discussed in this paper is the difference between the potential farm yield and the actual average farm yield. In Bangladesh, yield gaps exist in different crops ranging up to 60%. According to the recent study conducted by BRRI, the yield gap in rice was estimated at 1.74 t/ha. The existence of yield gaps was as well observed in rice, mustard, wheat and cotton in India. In India, yield gap varied from 15.5 to 60% with the national average gap of 52.3% in irrigated ecosystem. The yield gaps are mainly caused by biological, socio-economic, climate and institutional/policy related factors. Different strategies, such as integrated crop management (1CM) practices, timely supply of inputs including credit to farmers, research and extension collaboration to transfer the new technologies have been discussed as strategies to minimize yield gaps. Suggestions have been made to make credit available to resource-poor small farmers to buy necessary inputs. Reducing transaction cost, simplifying lending procedures and strengthening monitoring mechanism of the current credit system are, however, essential to enable the farmers to avail the credit facility. Efforts should be made to update farmers’ knowledge on the causes of yield gaps in crops and measures to narrow the gaps through training, demonstrations, field visits and monitoring by extension agencies to achieve high yield. The government should realize that yield gaps exist in different crops of Bangladesh and therefore, explore the scope to increase production as well as productivity of crops by narrowing the yield gap and thereby ensure food security. Keywords: Yield gaps; strategies; crops of Bangladesh. DOI: http://dx.doi.org/10.3329/bjar.v36i3.9274 BJAR 2011; 36(3): 469-476


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