|Shukla, Vijaya -|
Submitted to: Book Chapter
Publication Type: Book / Chapter
Publication Acceptance Date: August 22, 2013
Publication Date: January 10, 2014
Citation: Shukla, V., Mattoo, A.K. 2014. Developing robust crop plants for sustaining growth and yield under adverse climatic changes. In: Tuteja, N., Gill, S.S., editors. Climate Change and Abiotic Stress Tolerance. Wiley-VCH. p. 27-56. Interpretive Summary: Crops suffer significant damage, and productivity decreases under abiotic stresses such as drought, heat and radiation. The anticipated climate change will add to these losses because elevated temperature and high carbon dioxide levels will create drought conditions and increased soil salinity. Research thrusts in applying plant molecular biology and molecular genetics tool-kits have designed strategies to develop new crop germplasm that can adapt quickly and adjust cellular metabolism to the changes in climatic conditions and produce more with higher grain filling capacity while being resistant to existing and new pests/pathogens. This invited book chapter summarizes research findings that have made serious inroads in identifying and validating the gene markers, transcription factors, critical osmolytes and other metabolites that can sustain crop growth and yield under conditions of high temperatures and drought. This knowledge base should be of interest to agricultural scientists, researchers and policy makers alike in helping develop modified germplasm that can not only withstand the harsher climatic conditions but also enhance yield and quality of the crops.
Technical Abstract: Agricultural production and quality are expected to suffer from adverse changes in climatic conditions, including global warming, and this will affect worldwide human and animal food security. Global warming has been shown to negatively impact crop yield and therefore will affect sustainability of agriculture. Crops exposed to higher than optimum temperatures and/or facing drought during reproductive stages have lower grain yield, and if this exposure persists on a regular basis global crop production will ultimately decline drastically. Increased atmospheric CO2 levels associated with global warming will likely have a positive effect on crop photosynthesis and transpiration, but the overall negative effects of higher temperatures and drought conditions together could be lethal. To sustain crop growth and protection there is a dire need to develop stress-tolerant crops. Breeding strategies assisted by molecular markers could identify resilient germplasm for developing stress-tolerant crops, but this approach may not be a timely solution because of limited germplasm resources and the slow nature of the process. Genetic manipulation to improve stress tolerance in crops against heat, drought and salinity is a relatively more effective technology since a number of critical genes, particularly transcription factors, that regulate gene expression in response to environmental stress have been identified and validated to provide tolerance against multiple abiotic stressors in a wide variety of crops including rice, wheat and maize. In this chapter, we bring together selective examples that highlight the recent developments in engineering transcription factors, other proteins, osmolytes and molecules such as polyamines, which provide plants with tolerance to adverse climatic extremes.