YIELD, PROFIT, AND KNOWLEDGE GAPS IN RICE FARMING: CAUSES AND DEVELOPMENT OF MITIGATION MEASURES - V. Balasubramanian, M. Bell, and M. Sombilla^*

^* International Rice Research Institute (IRRI), MCPO 3127, 1271 Makati, Philippines.

More than 250 million farm families cultivate rice in Asia (Hossain and Pingali 1998). In the past three decades, they produced 2.5 percent more rice each year to meet the growing food demand (Hossain and Fischer, 1995). This tremendous achievement was possible due to the development and use of high yielding rice varieties, provision of assured water supply, liberal application of fertilizers and pesticides, and focused institutional and policy support for rice crop intensification. According to Hossain (IRRI, 1998-1999), making cheap rice available to millions of poor consumers is the single most important contribution that IRRI has made in the Asia-Pacific Region.

However, it appears that we have exhausted the potential of the ‘green revolution’ strategies, as we witness declining rice productivity in many countries. In the next 3 decades, farmers need new approaches and technologies to produce 50 to 60 percent more rice on existing or less land and water with limiting and/or expensive inputs. The three factors that could contribute to increased rice productivity are: (a) developing new rice varieties including hybrids with higher yield potential; (b) minimizing the yield gap between what is currently harvested by farmers and the achievable highest on-farm yield of varieties they grow; and (c) reducing the post-harvest losses and improving grain quality to enhance profitability. This paper elaborates on rice yield, profit and knowledge gaps, with brief discussion on yield ceiling to provide a complete scenario.

2. DEVELOPING RICE VARIETIES WITH HIGHER YIELD POTENTIAL

The potential yield is 10 t ha^-1 for presently available semi-dwarf indica rice varieties. An additional 10 to 15 percent increase in rice yields can be expected with the development of tropical rice hybrids (Virmani et al., 1991) which are currently being introduced to many Asian countries. New Plant Type (NPT) lines are being developed to further increase the potential yield of rice varieties.

2.1 New Plant Types

IRRI-developed NPT lines, popularly termed by the media as ‘super rice’, are expected to yield 12.5 t ha^-1. Development of hybrids using NPT could increase the yield further to 14-15 t ha^-1. Research is ongoing to incorporate resistance/tolerance to major insect pests and diseases and to improve grain quality. Fully developed NPT lines will become available for testing in farmers’ fields by the year 2001-2002.

2.2 Hybrid Rice Technology

Hybrid rice technology is complex in terms of production of quality seed and crop management. Virmani and Sharma (1994) have developed a manual for producing hybrid seeds in the tropics. The Directorate of Rice Research, Hyderabad, India, has developed a production package for hybrid rice (DRR, 1998): nursery seeding rate of 10-20 g m^-2; 1-2 seedlings per hill; herbicide + one hand weeding; 150 kg N ha^-1 with adequate P, K, Zn, and S; continuous (5 cm water depth) or cyclic submergence; and adequate plant protection.

Proper choice and improvement of parental lines for resistance to pests and diseases as well as better grain quality, development of 2-line hybrids, maintenance of genetic purity of parental lines of popular hybrids, and refinement of a seed production package may enhance the spread of hybrid rice in tropical Asia (Paroda, 1998). Hybrid rice technology should only be promoted in areas best suited for its cultivation. Private sector seed companies have a critical role to play in the supply of quality hybrid seeds to farmers at affordable prices.

3. TYPES OF RICE YIELD GAPS

There are different types of yield gaps: gap between genetic potential and biologically attainable yields, variability in rice yields in different regions, gap between research station and farmers’ yields, and yield differences among farmers in a given homogenous environment.

3.1 Gap between Potential and Attainable Yields

As discussed above, the potential yield of semi-dwarf indica varieties is 10 t ha^-1. However, under the best management conditions, farmers can reap 80 to 85 percent of the potential yield of varieties. The difference between genetic potential yield at the experiment station and the highest attainable yield in farmers’ fields is the yield gap due to environmental differences and non-transferable technology, and thus it cannot be bridged. If the potential yield of rice varieties is increased beyond 10 t ha^-1 by developing hybrids and New Plant Types, farmers can attain correspondingly higher yields when they use those varieties. This is the reason why rice breeders are trying to increase the potential yields.

3.2 Variability in Rice Yields in Different Countries and Regions

High variability exists in rice yields across countries and regions as shown in Table 1. This type of yield gap is due to differences in biophysical (climate, length of growing season, soil, water, pest pressure, etc.) and socio-economic factors, crop management, and access to and use of knowledge and technologies. For example, the high rice yield in Australia is due to:

· Favourable climate: high solar radiation, cloudless long growing season (150-180 days), optimum temperature.

· Precision crop management (crop rotation, single rice crop per year, smooth and level soil surface, use of registered pure seed every season, precise control of water level, high plant density, need-based/timely/balanced fertilizer application, high quality post-harvest management.

· Enlightened farmers and excellent technical support (Beecher, 1999).

Table 1. Mean Rice Yields (t ha^-1) in Different Countries and Regions (1994)

Country/Region	Area ‘000 ha	HYV coverage %	Yield t ha-1	Yield gap %
Countries
Australia	122	100	8.3	--
Egypt	579	--	7.9	4.8
USA	1,366	100	6.7	19.3
Japan	2,212	100	6.8	18.1
Spain	63	100	6.2	25.3
S. Korea	1,160	100	6.1	26.5
China	30,373	100	5.9	28.9
Regions
Europe	612	100	5.2	37.3
Asia	134,560	2-91	3.8	54.2
Latin America and Caribbean	5,723	47-100	3.2	61.4
Africa	7,929	--	2.2	73.5
World	150,305	--	3.7	55.4

The generally high yields obtained in temperate regions (record yields can go up to 14-15 t ha^-1) is mainly due to low night temperature, especially at the reproductive stage. We cannot modify the climatic regime and certain biophysical factors, but we can certainly improve the crop management of and technical support to rice farmers to improve rice productivity in Asia, Latin America and Africa.

The national mean, irrigated, and potential rice yields of selected countries of Asia are given in Table 2 (Pingali et al., 1997). The gaps between the potential and irrigated yields are small compared with gaps between the potential and the national average yields. Low yields of rainfed lowland and upland rice ecosystems bring down the national average yields. In such cases, the yields of rainfed lowland rice have to be improved by developing location-specific varieties and production technologies. The major targets for creating impact in rainfed lowland rice systems are: (a) developing varietal resistance to abiotic stress related to uncertain water supply, (b) improving dry seeding methods, (c) maintaining natural resilience of ecosystem to pests, and (d) incorporating micronutrients in rice (Fischer and Cordova, 1998).

Table 2. The National Mean, Irrigated, and Potential Rice Yields of Selected Countries (Adapted from: Pingali et al., 1997)

Country	National Mean Yield, t ha-1	Irrigated Rice Yield, t ha-1	Potential Rice Yield, t ha-1	Gap Between Potential and Irrigated Rice Yield, %	Gap Between Potential and National Mean Yield, %
Bangladesh	2.6	4.6	5.4	14.8	51.9
China	5.7	5.9	7.6	22.4	25.0
India	2.6	3.6	5.9	39.0	55.9
Indonesia	4.4	5.3	6.4	17.2	31.3
Nepal	2.5	4.2	5.0	16.0	50.0
Myanmar	2.7	4.2	5.1	17.6	47.1
Philippines	2.8	3.4	6.3	46.0	55.6
Thailand	2.0	4.0	5.3	24.5	62.3
Vietnam	3.1	4.3	6.1	29.5	49.2

3.3 Gaps between Maximum Attainable and Economically Exploitable Yields

Rice yields of experimental plots represent the maximum attainable yields with no physical, biological and economic constraints. They also reflect the knowledge frontier and best known management practices at any given point in time (Pingali et al., 1997). When the target is to maximize profits, the yields obtained are lower than maximum attainable yields (Herdt, 1988). This is termed as the economically exploitable yields. Farmers tend to maximize profits, but consistent with high economically exploitable yields. Exploitable yields are slightly higher in research plots than in farmers’ fields as observed in the Philippines (Otai, 1997) - Table 3. The gap in exploitable yields between on-farm research plots and farmer cooperators’ fields is less than 6 percent in both seasons. This means that farmer cooperators have learned the improved farming techniques by continuous interaction with researchers and observations of the crop management activities and yield superiority in research plots located in their own fields. On the contrary, the yield gap between on-farm research plots and non-cooperators is 14 percent during the wet season and as high as 39 percent in the dry season. This signifies that farmer non-cooperators operate at low efficiency, for they have yet to learn more about the improved crop management practices either from their neighbours or from research/extension staff.

Table 3. Mean Fertilizer Inputs and Rice Yields in On-farm Research Trials, Farmer Cooperators’ Fields, and Non-cooperators’ Fields, Maligaya, Central Luzon, Philippines, 1996-97

Particulars	No. of Farms	Mean N-P-K, kg ha-1	Mean Yield, t ha-1	Yield gap, %
1996 Wet Season (July to October)
On-farm trials	17	61-20-26	4.16 (1.01)*	--
Farmer cooperators	28	102-16-23	3.96 (1.31)	4.8
Farmer non cooperators	39	117-7-11	3.56 (0.83)	14.4
1997 Dry Season (January-April)
On-farm trials	17	94-12-31	6.92 (0.90)	--
Farmer cooperators	28	130-11-27	6.52 (1.02)	5.8
Farmer non-cooperators	39	145-7-13	4.25 (1.23)	38.6

Source: Otai, 1997.
* Figures in brackets are standard deviation of the mean.

Figure 1. Relationship between grain yield and rate of N application in rice by progressive farmers of Guyana, Spring 1999

Table 4. Mean Yields of Current Commercial Rice Varieties in Breeding Experiments and on Farmers’ Fields, Guyana, Spring 1999 (adapted from Shrivastava et al., 1999)

Farmer/Research Station	Area, ha	Variety	N-P-K, kg ha-1	Yield, t ha-1	Yield Gap, %
S. Yaap	2.0	BR 240	80-16-0	6.55
P. Lall	2.4	G 95-4	86-17-0	6.51
B. Ramnarine	3.8	Rustic	54-8-0	6.12
A. Aiyad	2.0	Rustic	70-16-0	6.02
Heeralal	1.0	Rustic	52-12-0	6.19
S. Seecharan	5.2	Rustic	101-10-0	6.93
Chaitram	5.2	Rustic	60-21-0	6.40
Sesnarine	2.0	Rustic	80-16-0	7.68
P. Buddhoo	2.0	Rustic	52-12-0	5.49
A. Mohammed	1.5	BR 444	26-12-0	5.49
C. Singh	81.2	BR 240	28-5-8	5.49
I. Alladin	24.2	F7-10	39-6-0	4.71
Farmers’ mean Breeding	21.2 Small plot	Rustic Rustic	67-14-0	6.45 4.39	-- 31.9
Breeding	-- do --	BR 444		5.71
Breeding	-- do --	Diwani		6.37
Breeding	-- do --	F7-10		5.22

3.4 Rice Yield Differences among Farmers in a Homogenous Region

All farmers do not operate at the same efficiency level. In a survey of rice farmers in Maligaya, Central Luzon, Philippines, Otai (1997) found that there were significant differences in rice yields of on-farm trials, farmer cooperators, and non-cooperators during the 1996 wet season and the 1997 dry season (Table 3). PhilRice has estimated that only 40 percent of the farmers are as efficient as the best farmers and obtain high yields. About 50 percent of the farmers obtain 3.0 t ha^-1 or less and 70 percent of the farmers 4 t ha^-1 or less. The average national rice yield is 3.3 t ha^-1. This average yield can be increased to 5.0 t ha^-1 with currently available technologies. Additional data in Table 4 demonstrate the differences in rice yields among farmers in Guyana. Significant yield differences among rice farmers do exist in other countries as well.

Certain factors (Figure 2) are responsible for yield gaps among farmers: biological (soil, water, seed quality, pests); socioeconomic (social/economic status, family size, household income/expenses/investment); farmer knowledge (education level) and experience; farmers’ management skills; farmers’ decision making (attitude, objectives, capability, behavior); and institutional/policy support (rural development & infrastructure, land tenure, irrigation, price, tax, crop insurance, etc.). All these factors should be addressed to reduce the yield gaps among farmers.

Figure 2. Yield gaps and constraint research model (Source: De Datta et al 1978)

Progressive farmers differ from other farmers in adapting the knowledge and technologies to their own conditions to attain high yields in their region. We have to identify the set of best farmers’ practices that can be transferred to other farmers so as to improve their efficiency in farming.

4. CROP MANAGEMENT TECHNOLOGY OPTIONS FOR REDUCING YIELD GAP

Rice production is coming under increasing pressure in Asia due to population growth and changing socio-economic factors. Land, water and labor resources are increasingly less available for rice production, while at the same time, the demand for rice and for improved grain quality is increasing. To meet the challenges, technologies within the production and post-production chains are changing (Table 5). The extent of the relevance of technological options depends in large part on the scales of production and the availability of resources. Improved technology options available for rice farmers are listed below:

· Land Preparation and Leveling: laser-aided precision leveling; herbicide-based minimum tillage; dry shallow tillage prior to puddling; shallow tillage soon after harvest to incorporate crop residues and improve soil N supply; hydrotiller, hand tractor, 4-wheel tractor.

· Crop Establishment: transplanting machine; seedling broadcast; drum seeder, tiller-seeder-planking attachment for hand-tractor, and seed-cum-fertilizer drill.

· Water Harvesting and Management: farm pond; dry seeding; drought-tolerant varieties; improved irrigation & drainage channels; saturated water condition for wet-seeded rice; cyclic/intermittent irrigation (wetting and drying).

· Integrated Nutrient Management (INM): organic + chemical fertilizers; balanced, field-specific fertilizer recommendation; K in two splits; soil-test based S, Zn; real time N management with chlorophyll meter & leaf color chart; deep placement of urea briquette; coated controlled release urea.

· Integrated Weed Management (IWM): cultural practices to minimize weed problem; row seeding + cono weeder package; timely and judicious herbicide use.

· Integrated Pest Management (IPM): no early spraying against leaf folders and thrips; pheromone traps for yellow stem borer; active barrier system for rat control; deployment of pest-resistant varieties; silica application for blast control; timely and judicious use of bio and/or chemical pesticides.

· Post-harvest Technologies: improved serrated sickle; reaper; thresher; stripper harvester; combine; dryer; cleaner; improved mills; micro rice mill.

· By-products Utilization: rice hull stove, rice hull briquette; rice bran oil extractor; rice hull ash + cement for hollow blocks; rice hull mulch for cut flower gardens and mushroom culture; rice puff machine; rice wine making.

Table 5. Shifts in Factors and Technologies and their Implications

Factors	Shift	Implications
		Positive	Needs & Concerns
Production Factors
Land preparation	Manual and hand tractor to 4 wheel tractor	Improved land preparation, Timeliness	Mobility and improved drainage required
Variety	Traditional to modern HYVs	Higher yield potential	Meeting grain quality and demands of markets
Seed quality	Poor/ordinary seed to improved, quality seed	Increased yield, reduced seed-borne pests, less weeds	Farmer training on benefits and production of quality seeds; source, storage conditions, seedling vigor
Crop establishment	Manual transplanting to machine trans-planting and direct seeding (wet & dry)	Reduced labor, less drudgery, improved timeliness	DSR: Weed pressures (red rice); need for better land leveling & improved water management
Pest management Weeds Insects Diseases Birds Rats Snails	From manual to chemical From calendar based application to integrated pest management (IPM)	IPM utilizes benefits of different forms of control and reduces reliance on chemicals.	With chemical control - selection of quality product, use of correct dose, uniformity of application; safety for the user and the environment, quality of products
Water management	Less available water- Better maintenance of irrigation & drainage structure; Shifts to low water levels, cyclic irrigation	Less water use, more area irrigated, higher water use efficiency	Cost of maintenance, community decision making in sharing water, pricing water, and weed problems
Nutrient management	Shift from blanket to site-specific, need-based nutrient management (chlorophyll meter, color chart); balanced NPK and other nutrients, INM	Less fertilizer cost, same or higher yields, less pests/diseases, less lodging, better quality water and soil.	Labor for adoption of certain techniques, cost of tools, quality assurance in decision tools, fertilizer quality
Post-production Factors
Harvesting and threshing	Manual to reaper/thresher to combine	Low labour requirement timely harvest and therefore better quality grain	Mobility - water management and field layouts required for larger equipment
Drying	Sun-drying to mechanical dryers	Timely drying, less spoilage and better quality grain	Cost of dryers, energy source and cost, utilization time, market incentive for dry grains
Cleaning	No or little cleaning (e.g., winnowing) to mechanical	Reduced pest and debris load; higher quality grain, less spoilage in storage	Cost of grain cleaners, power sources, market incentive for clean grains
Storage	Bag to bulk	Centralized, modern storage facilities; maintenance of better grain quality	Moisture content management, Spoilage from discoloration and insects, if not adequately treated and/or dried; not farm level
Milling	Hand pounding to steel huller to modified steel huller to rubber roll	Better quality grain’ Higher head rice yields	Adequate moisture content, maintenance of parts
Grain quality	Quantity to quality	Higher price and profitability	Production and post production management
Socio-economic Factors
Marketing	Subsistence to cooperative to commercial	Farmers obtain higher incomes through direct marketing	Organization and management skills; procurement of facilities
Credit	From money lenders to cooperatives and banks	Credit at low interest, inputs, and technical advice	Organization, collateral requirement, delay in credit delivery
Knowledge transfer	Alternate partners: NGOs, Cooperatives, Private sector	More choice and may be better and timely service; client-oriented	Profit motive of POs; less technical knowledge of NGOs

5. PROFIT GAPS DUE TO POST-HARVEST LOSSES

About 20 to 25 percent of the harvested rice is lost before it reaches the consumers’ table. The post-harvest losses in both quantity and quality lead to substantial profit gaps among farmers. Improved processing, storage, and direct marketing will help farmers to increase their profits. Effective farmer organizations such as cooperatives can assist farmers in post-harvest processing and marketing.

For better grain quality and higher head-rice yield, production and post-production practices have to be improved. Harvesting, threshing, cleaning, drying, and parboiling/drying are labour intensive operations in developing Asian countries. These operations must be carried out at the right time to minimize losses and to ensure good grain quality. Improvement and appropriate mechanization of these operations will depend on the market demand and price incentive for quality rice. The level of processing, i.e., at farm, village or mill level, will determine the type of equipment needed. Most post-harvest equipment will require some minimum economy of scale for their profitable operation. Organization of user groups is vital to successfully introduce such equipment (D. de Padua, Consultant to IRRI AED, IRRI, Philippines, 1998, personal communication).

Harvesting

Farmers must harvest the crop at optimum maturity when 80 to 85 percent of the grains are straw-coloured and the grain moisture content (MC) is 20 to 25 percent. A good indicator is that the grains will be firm but not brittle at optimum maturity. Harvested crops will dry at 1 to 2 percent moisture per day. Harvesting of very dry crops will increase shattering losses and breakage of grains at threshing and milling. Machines available for harvesting and cleaning are: reaper harvester, stripper gatherer, thresher, combine harvester, and cleaner.

Threshing

Harvested crops should be threshed soon; otherwise, the grain quality will deteriorate with longer waiting between harvesting and threshing. Machine threshing is normally done immediately after harvesting when the grain MC is 20 to 25 percent. If the grain MC is < 20 percent or > 25 percent, grain damage will occur at machine threshing. Hand threshing is normally done one to two days of field drying after harvest, when the grains reach 20 percent MC. If the grain MC is > 25 percent, it will be difficult to thresh and separate the grains from panicles by manual threshing.

Drying

Rice grains are dried to 14 percent MC before storage. Sun drying is the most common method used by farmers in Asia. If properly done, the moisture will be reduced from 20 to 14 percent in one day. Grain damage by rains, wind, or by birds is common in open drying floors. Different types of dryers are available for drying wet rice: low cost in-store dryer (SRR) (1-2 tonnes/60-70 h), flat bed dryer (4-6 tonnes/8 h), columnar batch recirculating dryer (1-2 tonnes/6-8 h), etc. The grain quality is good and the germination percent is high with machine-dried rice.

Milling and Grain Quality

In rural areas, small mills (0.25 to 0.50 tph) are common. Grain quality is poor in these mills due to the use of Engleberg type steel hullers for dehusking and polishing in one pass. Small-scale commercial mills with 1-2 tph capacity use rubber rollers to improve grain quality.

Millers and traders maintain high grain quality for export rice. The quality criteria differ for different markets and types of rice. The private rice industry has developed many post-harvest procedures to meet the quality standards of various markets. They are mostly kept as trade secrets. For example, the processing of quality long grain rice involves:

· Dry to 13 percent moisture just before milling.

· Use cream coloured, soft rubber rollers for dehusking, with both rollers adjusted exactly parallel to each other.

· Adopt 4-5 passes for polishing, tempering the grains for 6-8 hours between passes.

· Use water polishing for shiny grains.

· Adopt lens grading for removal of smalls and brokens.

There are considerable knowledge gaps between researchers, extension agents, and farmers. We need to train the (government, non-government, private sector) extension staff and equip them with adequate tools so that they can educate their farmer-clients. Farmers need adequate training and technical support to improve their decision-making capacity.

6.1 Farmers’ Knowledge vs. Researchers’ Insights

Farmers’ experience or indigenous knowledge (IK) is accumulated over generations. Scientists’ technical knowledge is synthesized from years of research. These two systems of knowledge should be integrated for the benefit of both and to enhance mutual learning to reduce knowledge gaps between farmers and researchers.

6.2 Knowledge gap between researchers and extension staff

The new knowledge and technologies are not reaching most of the farmers due to poor extension efforts in this area. The extension service in many countries is very poorly trained and equipped to handle delivery of new knowledge from researchers to farmers. This lacuna should be urgently addressed.

The technology delivery system should be re-oriented to handle changing circumstances and to deliver complex, knowledge-intensive technologies to farmers. We need to explore private sector extension agencies in commercial farming areas and other service-oriented agencies (NGOs) in food crop areas to extend new knowledge and technologies to farmers. All of them should be properly trained and equipped to promote new technologies. The effectiveness of different combinations of public, private, cooperative and NGO extension agencies is being evaluated.

6.3 Farmer Education

Continuous farmer education is necessary to make them understand scientific principles of crop and resource management; adjust various inputs to temporal and spatial variability of rice fields; adopt integrated nutrient, water, weed, and pest management; and increase farm income through efficient post-harvest processing and utilization of byproducts. For example, we are adapting simple decision tools such as the chlorophyll meter and leaf colour chart (LCC) to enhance their knowledge in need-based N management of rice crops.

We can use different ways to transfer the knowledge to farmers: farmer field school (FFS), farmer participatory research (FPR), private advisory groups, etc. FFS imparts systematic experience learning to farmers so that they can effectively adapt and use the technologies. Through appropriate FPR, we can equip farmers with scientific principles of crop and resource management that they can use to adapt/refine new technologies to their own circumstances and needs. The new knowledge should be couched in farmers’ familiar terms and allow them to experiment and evaluate it in their own way till they get convinced. This will facilitate the incorporation of new knowledge into farmers’ own knowledge base.

6.4 Communication Strategies

Successfully evaluated technologies should be disseminated to farmers in a large area to have a wider impact. We are evaluating effective communication technologies such as radio and television (mostly one-way, large audience, time lag); two-way radio and telephone (two-way, timely, need-based, interactive); and internet/web-based communication (distance learning/teaching) for disseminating knowledge and technologies. We can use the GIS, crop models, and systems approaches to replicate successful outcomes in space and time.

6.5 Institutional/Policy Support

Adequate rural infrastructure such as farmer training institutions, various groups of extension/technology delivery agencies, farm credit organizations, inputs/machinery suppliers, marketing outlets and traders, road, transport and communication networks and product quality and grading centres should be present to encourage farmers to produce food efficiently. Policy support in terms of pricing of inputs and outputs, incentives for farmers to encourage food production, land tenure, tax, crop insurance, etc., will optimize farmers’ productivity.

6.6 Crop and Resource Management Network (CREMNET)

Field evaluation and delivery of the new knowledge and technologies to farmers are vital to achieve impact on productivity. We at IRRI, have developed a network to deal with the diffusion of information, knowledge, and technologies to rice farmers. This is called CREMNET, the Crop and Resource Management Network.

This network acts as a bridge between two groups of R and D partners: those who generate new research findings and technologies at the one end and those who evaluate, adapt, and promote the technologies for use by farmers at the other end. CREMNET encourages the two-way flow of information and feedback between these two groups to improve the efficiency of both.

In the network mode of operation, we serve as a catalyst to national R and D organizations to promote the applied, adaptive, and farmer participatory research on potential crop and resource management technologies suitable for their regions. In this process, we also help in strengthening the national R and D institutions through sharing of information, knowledge, techniques, tools, and methods, as well as by training collaborators. Our ultimate aim is to bridge the knowledge systems gaps of rice scientists and farmers to maximize mutual benefits.

7. CONCLUSIONS

There is high variability in rice yields among countries and regions as well as among farmers even in homogeneous domains. Profit gaps arise due to post-harvest losses in quantity and quality of rice grain. Biophysical, socio-economic, management, institutional, and policy factors are responsible for yield and profit gaps. Identification of problems/causes for such gaps and development of possible mitigation measures can only be considered the first of a two step process. The second and equally important step is to minimize the knowledge gap between researchers, extension staff and farmers by developing and using viable mechanisms to transfer new knowledge and techniques from researchers to farmers and collect feedback to re-orient research on issues critical to farmers.

An integrated crop management approach (water, soil fertility/nutrients, weeds/pests/diseases, and post-harvest processing) is vital to maximize the productivity and profitability of rice farmers. All technologies and practices should be used synergistically to help farmers increase and/or maintain grain yields at the same or reduced cost. Improving the quality of milled rice and increasing the recovery of head-rice will enhance farmers’ profitability.

We need to train the (government, non-government, private sector) extension staff and equip them with adequate tools so that they can educate their farmer-clients on modern rice farming. Farmers need adequate training and technical support to improve their decision-making capacity and properly utilize the new techniques.

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