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Flooding and Submergence Tolerance

  • Abdelbagi M. IsmailEmail author
Chapter

Abstract

Rice is the major crop in most rainfed and flood-prone environments of South and Southeast Asia and it provides food for millions of subsistence farming families. The productivity of these environments is low because high-yielding varieties tolerant of prevailing abiotic stresses are lacking. The hydrologic conditions in these environments are particularly harsh and unpredictable, leading to recurring floods and sometimes drought and salinity. Early floods cause poor crop establishment, and plant survival and yield decline drastically when plants are partially or completely submerged during the season. Traditional rice landraces predominate in these areas because they acquired partial tolerance against most of these stresses, but they are low yielding. Transferring tolerance traits into high-yield backgrounds will help boost and sustain the productivity in these areas, and this is becoming more feasible with the recent availability of effective genomics and molecular breeding tools that are being used to dissect and transfer these favorable traits and genes. These tools are providing opportunities to develop resilient varieties for the less favorable environments, and varieties that can tolerate complete flooding during germination and vegetative stage (conferred by SUB1) as well as yield well under long-term stagnant floods are becoming available. These varieties will also provide opportunities for better land productivity by being more responsive to inputs and other adjustments in the system, helping farmers cope with the existing problems and future adversities of climate change.

Keywords

Rice Variety Direct Seeding Tolerance Trait Submergence Tolerance Deepwater Area 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

Notes

Acknowledgments

The research summarized in this chapter was funded by numerous donors; I would like to particularly acknowledge the support of the German Federal Ministry for Economic Cooperation and Development (BMZ) and the Bill and Melinda Gates Foundation for funding most of our recent work. The author is also indebted to the various colleagues who coauthored most of the papers cited in this review.

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Authors and Affiliations

  1. 1.International Rice Research Institute, DAMetro ManilaPhilippines

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