Manila, Philippines

The International Rice Research Institute is an international independent research and training organization with headquarters in Los Baños, Laguna in the Philippines and offices in sixteen countries. The non-governmental organization was established in 1960 to develop new rice varieties and rice crop management techniques with finding sustainable ways to improve the well-being of poor rice farmers and consumers as well as the environment in mind.The institute is one of 15 agricultural research centers on the world that form CGIAR. It is also the largest non-profit agricultural research center in Asia.IRRI received the 2010 BBVA Foundation Frontiers of Knowledge Award in the category of Development Cooperation. Wikipedia.

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Chauhan B.S.,International Rice Research Institute
Crop Protection | Year: 2013

Weedy rice, an emerging problem in Asia, increases production costs and reduces farmers' income through yield reduction and through lowered rice value at harvest. Rice farmers in many Asian countries are shifting from transplanting to direct seeding; however, due to physical and physiological similarities of weedy rice to cultivated rice and the absence of standing water at the time of crop emergence, adoption of direct-seeded rice systems makes weedy rice infestation one of the most serious problems. Selective herbicides to control weedy rice in conventional rice cultivars are not available and therefore managing weedy rice is a challenging and increasing problem for farmers in Asia. In the absence of selective herbicides, various cultural weed management strategies may help reduce the problem of weedy rice. These strategies may include the use of clean seeds and machinery, use of stale seedbed practice, thorough land preparation, rotation of different rice establishment methods, use of high seeding rate and row-seeded crop, use of purple-coloured cultivars, use of flooding, and adoption of crop rotation. © 2013 Elsevier Ltd.

Chauhan B.S.,International Rice Research Institute
Weed Technology | Year: 2012

Rice is a principal source of food for more than half of the world population, and more than 90% of rice worldwide is grown and consumed in Asia. A change in establishment method from manual transplanting of rice seedlings to dry-seeded rice (DSR) has occurred in some countries as growers respond to increased costs or decreased availability of labor or water. However, weeds are a major constraint to DSR production because of the absence of the size differential between the crop and the weeds and the suppressive effect of standing water on weed growth at crop establishment. Herbicides are used to control weeds in DSR, but because of concerns about the evolution of herbicide resistance and a scarcity of new and effective herbicides, there is a need to integrate other weed management strategies with herbicide use. In addition, because of the variability in the growth habit of weeds, any single method of weed control cannot provide effective and season-long control in DSR. Various weed management approaches need to be integrated to achieve effective, sustainable, and long-term weed control in DSR. These approaches may include tillage systems; the use of crop residue; the use of weed-competitive cultivars with high-yield potential; appropriate water depth and duration; appropriate agronomic practices, such as row spacing and seeding rates; manual or mechanical weeding; and appropriate herbicide timing, rotation, and combination. This article aims to provide a logical perspective of what can be done to improve weed management strategies in DSR. © 2012 Weed Science Society of America.

Von Caemmerer S.,Australian National University | Quick W.P.,International Rice Research Institute | Quick W.P.,University of Sheffield | Furbank R.T.,CSIRO
Science | Year: 2012

Another "green revolution" is needed for crop yields to meet demands for food. The international C4 Rice Consortium is working toward introducing a higher-capacity photosynthetic mechanism - the C 4 pathway - into rice to increase yield. The goal is to identify the genes necessary to install C4 photosynthesis in rice through different approaches, including genomic and transcriptional sequence comparisons and mutant screening.

Chauhan B.S.,International Rice Research Institute
Weed Science | Year: 2012

Weedy rice is a serious problem of cultivated rice in most of the rice-growing areas in Asia, causing increased production costs and yield losses in rice. A study was conducted to determine the response of weedy rice accessions from India (IWR), Malaysia (MWR), Thailand (TWR), and Vietnam (VWR) to seed burial and flooding depths. The greatest emergence for each weedy rice accession (97% for IWR, 82% for MWR, 97% for TWR, and 94% for VWR) was observed in seeds placed on the soil surface. Seedling emergence decreased with increase in burial depth. For the IWR accession, 0.5% of the seedlings emerged from 8-cm depth, whereas for the other three weedy rice accessions, no seedlings emerged from this depth. When seeds were sown on the soil surface, flooding depth ranging from 0 to 8 cm had no or very little effect on seedling emergence of different weedy rice accessions. On the other hand, flooding decreased seedling emergence in all weedy rice accessions when seeds were sown at 1 cm deep into the soil. Compared with seedling emergence, flooding had a more pronounced effect on seedling biomass for all weedy rice accessions. A flooding depth of 2 cm reduced seedling biomass by an amount greater than 85% of each weedy rice accession. The results of this study suggest that emergence and growth of weedy rice could be suppressed by deep tillage that buries seeds below their maximum depth of emergence (i.e., > 8 cm for the accessions studied) and by flooding fields as early as possible. The information gained from this study may help design cultural management strategies for weedy rice in Asia. © 2012 Weed Science Society of Americ.

Water scarcity and drought have seriously threatened traditional rice cultivation practices in several parts of the world, including India. Aerobic rice that uses significantly less water than traditional flooded systems has emerged as a promising water-saving technology. The identification of QTL conferring improved aerobic adaptation may facilitate the development of high-yielding aerobic rice varieties. In this study, experiments were conducted for mapping QTL for yield, root-related traits, and agronomic traits under aerobic conditions using HKR47 × MAS26 and MASARB25 × Pusa Basmati 1460 F2:3 mapping populations. A total of 35 QTL associated with 14 traits were mapped on chromosomes 1, 2, 5, 6, 8, 9, and 11 in MASARB25 x Pusa Basmati 1460 and 14 QTL associated with 9 traits were mapped on chromosomes 1, 2, 8, 9, 10, 11, and 12 in HKR47 × MAS26. Two QTL (qGY8.1 with an R2 value of 34.0% and qGY2.1 with an R2 value of 22.8%) and one QTL (qGY2.2 with an R2 value of 43.2%) were identified for grain yield under aerobic conditions in the mapping populations MASARB25 × Pusa Basmati 1460 and HKR47 × MAS26, respectively.A number of breeding lines with higher yield per plant, root length, dry biomass, length-breadth ratio, and with Pusa Basmati 1460-specific alleles in a homozygous or heterozygous condition at the BAD2 locus were identified that will serve as novel material for the selection of stable aerobic Basmati rice breeding lines. Our results identified positive correlation between some of the root traits and yield under aerobic conditions, indicating the role of root traits for improving yield under aerobic situations possibly through improved water and nutrient uptake. Co-localization of QTL for yield, root traits, and yield-related agronomic traits indicates that the identified QTL may be immediately exploited in marker-assisted-breeding to develop novel high-yielding aerobic rice varieties.

Agency: Cordis | Branch: FP7 | Program: CP-TP | Phase: KBBE.2011.3.1-01 | Award Amount: 8.94M | Year: 2012

Most plants use the C3 pathway of photosynthesis that is compromised by gross inefficiencies in CO2 fixation. However, some plants use a super-charged photosynthetic mechanism called C4 photosynthesis. The C4 pathway is used by the most productive vegetation and crops on Earth. In addition to faster photosynthesis, C4 plants demand less water and less nitrogen. Overall, our aim is to introduce the characteristics of C4 into C3 crops. This would increase yield, reduce land area needed for cultivation, decrease irrigation, and limit fertiliser applications. If current C3 crops could be converted to use C4 photosynthesis, large economic and environmental benefits would ensue from both their increased productivity and the reduced inputs associated with the C4 pathway. It is important to note that the huge advances in agricultural production associated with the Green Revolution were not associated with increases in photosynthesis, and so its manipulation remains an unexplored target for crop improvement both for food and biomass. Even partial long-term success would have significant economic and environmental benefits. Efficient C4 photosynthesis would be achieved by alterations to leaf development, cell biology and biochemistry. Although initially we will be using model species such as rice and Arabidopsis we envisage rapid transfer of technological advances into mainstream EU crops, such as wheat and rape, that are used both for food and fuel. We will build capacity for C4 research in Europe in this area by the training of future generations of researchers. To achieve this aim we need to increase our understanding of the basic biology underlying the C4 pathway. Our specific objectives will therefore address fundamental aspects of C4 biology that are needed for a full understanding the pathway. Specifically we aim: 1. To understand the roles and development of the two cell types (mesophyll and bundle sheath) in C4 plants. 2. To identify mechanisms controlling the ex

Agency: GTR | Branch: BBSRC | Program: | Phase: Research Grant | Award Amount: 266.43K | Year: 2012

Zinc (Zn) is an essential nutrient in micro-quantities for all living organisms. Deficiencies limit crop production in many parts of the world, and Zn is often deficient in the diet of humans subsisting on staple-food crops, causing severe health problems. An important strategy for dealing with this is to breed crops that are efficient in taking up Zn and concentrating it in edible plant parts. Rice is one of the main crops being targeted because of its global importance and the prevalence of Zn deficiency in populations subsisting on rice. However rice is unusual in its Zn relations compared with other cereals in two respects. First, it is mainly grown in submerged soils, and because of the peculiar biogeochemistry of submerged soils, Zn deficiency in the crop is widespread, affecting up to 50% of rice soils globally. Second, as a result of inherent physiological differences, little Zn is remobilized from existing plant reserves to grains during the grain filling growth stages, as in other cereals, so that Zn uptake appears to be one of the main bottlenecks limiting rice grain Zn contents. Research has shown that grain Zn concentrations in rice - already low compared with other cereals or pulses - are further reduced in Zn deficient soils, and large fertilizer additions are needed to overcome this. Dietary and crop Zn deficiency are inevitably linked in areas with low Zn soils, as in most parts of Asia where rice is the staple. Enhancing the Zn uptake capacity of rice varieties will therefore be crucial to increasing grain contents. It will also be important to understand long-term sustainability of growing high grain Zn rice under inherently Zn-limited conditions, and what can be done to avoid problems in the future. Current research at the International Rice Research Institute (IRRI) is using classical plant breeding combined with molecular biological markers for useful plant traits to develop rice varieties with high grain Zn contents and improved yields on Zn-deficient soils. Research is also underway to enhance grain Zn through agronomic means, including fertilizer and water management. However progress in these activities, and in understanding long-term sustainability issues, is constrained by our poor understanding of the mechanisms underlying genotype differences, and of the dynamics of plant-available Zn in the soil within the growing season and longer term. In recent research by members of the project team, we have shown that three key mechanisms enhance growth of rice seedlings in Zn deficient soil: (a) secretion from roots of Zn-chelating compounds called phytosiderophores and subsequent uptake of chelated Zn in the rhizosphere, (b) maintenance of new root growth, and (c) prevention of root damage by oxygen radicals linked to high bicarbonate concentrations. Studies with a limited set of genotypes suggest that Zn loaded into grains mostly comes from Zn uptake during the reproductive stages rather than by re-translocation from vegetative tissue. The mechanisms listed above in relation to seedling growth may also assure adequate Zn uptake during the reproductive phase. However, this has not been systematically investigated so far, nor have any genes related to reproductive-stage Zn uptake been tagged. The proposed research addresses these knowledge gaps with an interdisciplinary approach linking fundamental research on soil biogeochemistry, molecular physiology and genetics with applied work on agronomy and plant breeding, with a conceptual framework provided by mathematical modelling. Our goal is to develop genotypes and management practices for growing high Zn rice in Zn deficient soils, suitable for resource-poor farmers. This will encompass agronomic interventions based on understanding of limiting factors for Zn uptake and translocation, and breeding approaches based on understanding of genetic factors controlling key tolerance mechanisms.

International Rice Research Institute | Date: 2014-12-11

The present invention provides methods and materials useful for improving early vigor of plants during germination. The methods and materials described herein are useful for improving early vigor of plants grown under either aerobic or anaerobic conditions. In particular embodiments described herein, the methods and materials described herein are useful for improving anaerobic germination of plants.

International Rice Research Institute and Japan International Research Center For Agricultural Science | Date: 2014-04-28

Described herein are methods and materials useful for improving root growth and nutrient uptake in cereal grasses. In particular, present disclosure provides methods for increasing root growth and nutrient uptake in a cereal grass involving marker assisted selection and backcrossing. The present disclosure also provides recombinant DNA for the generation of transgenic plants, transgenic plant cells, and methods of producing the same. The present disclosure also provides materials and methods useful for improving the tolerance of a cereal grass to phosphorus-deficiency The present disclosure further provides methods for generating transgenic seed that can be used to produce a transgenic plant having increased root growth, nutrient uptake, and phosphorus-deficiency tolerance.

International Rice Research Institute | Date: 2014-10-08

Described herein are methods and materials useful for improving lateral root growth, water uptake, and the yield of grain of cereal grasses grown under drought stress conditions. In particular, the present disclosure provides a quantitative trait locus associated with improved yield under drought stress. The disclosure further provides recombinant DNA for the generation of transgenic plants, transgenic plant cells, and methods of producing the same. The present disclosure further provides methods for generating transgenic seed that can be used to produce a transgenic plant having improved yield under drought stress, and methods for improving yield under drought stress in a cereal grass involving marker assisted selection and backcrossing.

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