Yield gap variation in rice cultivation in Indonesia

Agricultural Systems, 2022

Food security Smallholder agriculture OBJECTIVE: The objective of this study was to decompose rice yield gaps into their efficiency, resource, and technology components and to map the scope to sustainably increase rice production across four lowland irrigated rice areas in Southeast Asia through improved crop management. METHODS: A novel framework for yield gap decomposition accounting for the main genotype, management, and environmental factors explaining crop yield in intensive rice irrigated systems was developed. A combination of crop simulation modelling at field-level and stochastic frontier analysis was applied to household survey data to identify the drivers of yield variability and to disentangle efficiency, resource, and technology yield gaps, including decomposing the latter into its sowing date and genotype components. RESULTS AND CONCLUSION: The yield gap was greatest in Bago, Myanmar (75% of Yp), intermediate in Yogyakarta, Indonesia (57% of Yp) and in Nakhon Sawan, Thailand (47% of Yp), and lowest in Can Tho, Vietnam (44% of Yp). The yield gap in Myanmar was largely attributed to the resource yield gap, reflecting a large scope to sustainably intensify rice production through increases in fertilizer use and proper weed control (i.e., more output with more inputs). In Vietnam, the yield gap was mostly attributed to the technology yield gap and to resource and efficiency yield gaps in the dry season and wet season, respectively. Yet, sustainability aspects associated with inefficient use of fertilizer and low profitability from high input levels should also be considered alongside precision agriculture technologies for site-specific management (i.e., more output with the same or less inputs). The same is true in Thailand, where the yield gap was equally explained by the technology, resource, and efficiency yield gaps. The yield gap in Indonesia was mostly attributed to efficiency and technology yield gaps and yield response curves to N based on farmer field data in this site suggest it is possible to reduce its use while increasing rice yield (i.e., more output with less inputs). SIGNIFICANCE: This study provides a novel approach to decomposing rice yield gaps in Southeast Asia's main rice producing areas. By breaking down the yield gap into different components, context-specific opportunities to narrow yield gaps were identified to target sustainable intensification of rice production in the region.

The important contribution of rice to global food security requires an understanding of yield gaps in rice-based farming systems. However, estimates of yield gaps are often compromised by a failure to recognize the components that determine them at a local scale. It is essential to define yield gaps by the biological limitations of the genotype and the environment. There exist a number of methods for estimating rice yield gaps, including the use of crop growth simulation models, field experiments and farmer yields. We reviewed the existing literature to (i) assess the methods used to estimate rice yield gaps at a local scale and to summarize the yield gaps estimated in those studies, (ii) identify practical methods of analysis that provides realistic estimates of exploitable rice yield gaps, and (iii) provide recommendations for future studies on rice yield gaps that will allow accurate interpretation of available data at a local level. Rice yield gap analysis can be simplified without sacrificing precision and context specificity. This review identifies the comparison of the attainable farm yield (the mean of the top decile) with the population mean, as a practical and robust approach to estimate an exploitable yield gap that is highly relevant at the local level, taking into account what is achievable given the local socioeconomic conditions. With this method we identified exploitable yield gaps ranging from 23 to 42% for one particular season in four different rice growing areas in Southeast Asia. To enable accurate estimation and interpretation of yield gaps in rice production systems, we propose a minimum dataset needed for rice yield gap assessment. Future studies on rice yield gaps should consider the region, season and crop ecosystem (e.g. upland rain-fed, lowland irrigated) as a minimum to facilitate decisions at a local level. In addition, we recommend taking into account the cultivar, soil type, planting date, crop establishment method and nitrogen application rates, as well as field topography and toposequence for rainfed systems. A good understanding of rice yield gaps and the factors leading to yield gaps will allow better targeting of agricultural research and development priorities for livelihood improvement and sustainable rice production.

Agronomy, 2021

In this study, we aimed to improve rice farmers’ productivity and profitability in rainfed lowlands through appropriate crop and nutrient management by closing the rice yield gap during the dry season in the rainfed lowlands of Indonesia. The Integrated Crop Management package, involving recommended practices (RP) from the Indonesian Agency for Agricultural Research and Development (IAARD), were compared to the farmers’ current practices at ten farmer-participatory demonstration plots across ten provinces of Indonesia in 2019. The farmers’ practices (FP) usually involved using old varieties in their remaining land and following their existing fertilizer management methods. The results indicate that improved varieties and nutrient best management practices in rice production, along with water reservoir infrastructure and information access, contribute to increasing the productivity and profitability of rice farming. The mean rice yield increased significantly with RP compared with FP...

Field Crops Research, 2019

Multiple crops can be grown sequentially on the same field within a 12-month period in tropical humid environments. Yield gap analysis focusing on both individual crop cycles and cropping systems can help identifying opportunities to increase annual productivity. Indonesia was used as a case study to evaluate options for increasing annual productivity in rice and maize through closure of existing yield gaps at both crop-cycle and cropping-system levels. A total of 31 (rice) and 11 (maize) sites for irrigated crops, and 24 (rice) and 29 (maize) sites for rainfed crops were selected based on their share of national harvested area. Crop modeling based on local weather, soil, and management data, together with average farmer yield data, were used to estimate yield potential and yield gaps for individual crop cycles (total: 367) and cropping systems (total: 154). Extra rice and maize production potential were estimated for different scenarios of crop intensification and/or cropland expansion and compared against projected increase in grain demand for the two crops by year 2035. Yield gaps were substantially larger in maize versus rice and, in the case of rice, yield gap was larger in rainfed lowland versus irrigated conditions. At national level, average farmer yield for irrigated rice and maize represented 63% and 44% of their respective yield potential (9.5 and 13.6 Mg ha −1) while, in rainfed conditions, average farmer yield was 52% (rice) and 42% (maize) of respective water-limited yield potential (9.2 and 12.2 Mg ha −1). Scenario assessment indicated that Indonesia can produce an extra 24 and 16 million metric tons (MMT) of rice and maize annually (respective 31 and 67% increase relative to current production) and reach near self-sufficiency for both crops on existing cropland area by closing current yield gaps to a level equivalent to 80% of yield potential (irrigated crops) or 70% of water-limited yield potential (rainfed crops). Analysis of cropping-system yield gaps indicated an additional potential increase in annual rice (3 MMT) and maize (11 MMT) production derived from adoption of crop sequences with highest annual yield potential combined with yield gap closure, though this may be limited by extra input requirements and/or increasing risk. Findings from this study demonstrate the utility of yield-gap analysis to estimate extra crop production potential derived from intensification at both individual-crop and cropping-systems levels.

1993

Bec.ause of questions concerni.ng the higll costSa:nd effectiveness of Indol'lesia~s current mi.-x: of policies aimed atpromoting riceself-sufficiency. attention has turned to dcvclopingmorc efficient policies directed to\\lurds tlchicving self-sufficiency through increases inL1fmCrS' yields. The main issue addressed in this paper is whether existing yic!ds. canbc improved. When a yield gap exists, either between farms ~md experimental trials or between groups of fanns, then the issue becomes bow to explain the gaJl~mdwhatpolic, action Should betaken. Th.c rohusm.css of conclusions is examined in view of the fact that conclUSIOns obtained in past an..'llysis of the issucshaveoften been inconsistent. ACKNOWLEDGEMENTS Fundmg fl)r this project wm, provided by the Austrnlhm Centre for International Agricultural Res~t.n:h. TIle rtllthor~ grmcJuUy HcknowJcoge ~lssisl;Ulce with concepts and wmlysis. wilhout impl katluns for the timtl ~;ontent of the paper. given by Phil Kokic (Austmlian Bureau of Agricultural and Resoun.:c Economics), K. P. KalimJiUl (Australi.

The importance of rice production in sub-Saharan Africa (SSA) has significantly increased over the past decades. Currently, rice plays a pivotal role in improving household food security and national economies in SSA. However, current rice productivity of smallholder farms is low due to a myriad of production constraints and suboptimal production methods, while future productivity is threatened by climate change, water shortage and soil degradation. Improved rice cultivars and agronomic management techniques, to enhance nutrient and water availability and use efficiencies and to control weeds, have the potential to increase yields. The aim of this study was to assess the relative contribution of such technologies to enhanced rice productivity. Relative yield gains emanating from nutrient, water and weed management were surveyed and calculated from literature. Partial budgeting was used to evaluate viability of fertilizer technology under GAP. Substantial yield gains ranging from 0.5 t ha À1 to 2.9 t ha À1 are projected following the use of improved technologies. Relative yield gains decreased in the following order: weed management (91.6%) > organic fertilizer application (90.4%) > bunding (86.7%) > mineral fertilizer application (51.9%) > tied ridges (42.6%). Combining fertilizer with unimproved rice cultivars led to negative returns. The lack of integration of improved technologies, to increase synergies and alleviate socio-economic constraints, largely explained the existing yield gaps. The gains obtained through improved rice cultivars can be further enhanced through application of Good Agricultural Practices (GAP), improving nutrient, water and weed management technologies, based on the local resource availabilities of small farms. We therefore propose adapting technologies to local conditions and developing and using rice production decision tools based on GAP to enable rice farmers in SSA to improve resource-use efficiencies and crop productivity at the farm level.

Journal of Agronomy and Crop Science, 2020

The demand for rice in Eastern and Southern Africa is rapidly increasing because of changes in consumer preferences and urbanization. However, local rice production lags behind consumption, mainly due to low yield levels. In order to set priorities for research and development aimed at improving rice productivity, there is a need to characterize the rice production environments, to quantify rice yield gaps-i.e. the difference between average on-farm yield and the best farmers' yield-and to identify causes of yield gaps. Such information will help identifying and targeting technologies to alleviate the main constraints, and consequently to reduce existing yield gaps. Yield gap surveys were conducted on 357 rice farms at eight sites (19-50 farmers per site) across five rice-producing countries in Eastern and Southern Africa-i.e. Ethiopia, Madagascar, Rwanda, Tanzania and Uganda-for one or two years (2012-13) to collect both quantitative and qualitative data at field and farm level. Average farm yields measured at the eight sites ranged from 1.8 to 4.3 t ha-1 and the average yield gap ranged from 0.8 to 3.4 t ha-1. Across rice growing environments, major causes for yield variability were straw management, weeding frequency, growth duration of the variety, weed cover, fertilizer (mineral and organic) application frequency, levelling and iron toxicity. Land levelling increased the yield by 0.74 t ha-1 , bird control increased the yield by 1.44 t ha-1 , and sub-optimal management of weeds reduced the yield by 3.6 to 4.4 t ha-1. There is great potential to reduce the current rice yield gap in ESA, by focusing on improvements of those crop management practices that address the main site-specific causes for suboptimal yields.

European Journal of Agronomy, 2012

Agronomy

Increasing productivity per unit area, hence closing the yield gap, is key to meeting cereal demand in sub-Saharan Africa. We assessed, with 114 farmers, the contribution of recommended agronomic practices (RAP) with or without NPK fertilization on yield gaps, and options to intensify productivity. Treatments included farmers’ practice (FP) as control, RAP with and without NPK, and farmer-selected best practices geared towards intensification (farmers’ intensification practice, FIP). RAP without fertilization and FIP significantly increased grain yield, each by ca. 12%, whereas RAP+NPK application produced ca. 33% extra yield, over FP. RAP gave the highest mean net income (ca. USD 220 ha−1), fertilizer costs made RAP+NPK gave the lowest mean net income (ca. USD 50 ha−1). Weeding and fertilization timing contributed most to yield variation among fields. Delay in weeding and fertilization created an average yield loss of 5.3 and 1.9 g m−2, per day delay, respectively. Exploitable yiel...

Rice is the most important food crop of the Asia-Pacific Region, demand of which is growing faster than the population. Over 90 percent of the world's rice is produced and consumed in this Region. Moreover, this Region, where more than 56 percent of the world's population live, adds 51 million more rice consumers annually. As a result, the thin line of rice self-sufficiency experienced by many countries is disappearing fast, and more countries are importing rice. How the current annual production of 538 million tonnes of rice can be increased to over 700 million tonnes by the year 2025, using less land, labour, water and pesticides is a serious question.