About this Research Topic
Growing world population is expected to cause a "perfect storm" of food, energy and water shortages by 2030 as demand for food and energy will jump by 50% and for fresh water by 30%. Globally, water scarcity accompanied by threat of climate change is a reality, signalling drought as a major constraint to crop production. This drives the demand of more food per drop of water. Enhancing stability in crops under water limiting environments is a major challenge. Past efforts have been successful in mitigating drought through empirical breeding for drought escape. The partially yield stability have resulted from genetic modification to develop appropriate phenology that are well matched with the water availability. However, drought tolerance is a complex trait with many contributing loci showing efficacy only under certain conditions. Thus, progress in understanding molecular and physiological nature of drought tolerance has been slow and adaptation of crops to drought through genetic means remains elusive because of limited efforts in drought dissection, development of high throughput phenotyping platform, poorly characterized target environment, and high genotype x environment interaction.
From trait evaluation to gene discovery and its deployment into varieties for drought tolerance is long drawn process. Recently, a great progress has been made in development of high throughput approaches in eco-physiology, genomics, phenomics, and geo-informatics which offer scope for tailor-made solutions to drought problems. Increasing water-use efficiency (WUE) has an option to produce high biomass with less water. Introducing photo-thermo-insensitivity for minimizing GXE interaction is important strategy for wider adaptability and more climate resilience. An eco-physiological approach to understand distribution and expression of traits and their significance at target environment is necessary. Some plants maintain turgor by reducing transpiration through increased stomatal resistance or decreased leaf area. Others maintain a favorable water balance by enhancing water uptake through development of extensive root system and by reducing internal resistance to water flow. However, many traits are very difficult to use in an empirical breeding program. Recent tools in genomics are comparative analyses across species and populations, high throughput mapping, identification of drought-associated genes, and characterization of mutations in candidate genes. These tools help in identification of genes involved in a trait, and correlations of alleles and/or expression patterns in those genes with the investigated trait. Plant genomics allows mapping of complex traits (QTLs) and allele mining in very large populations, and under different environmental condition. Hence, even minor contributing loci can be identified and mapped. Robust phenotyping high throughput systems are needed to characterize a complete set of genetic factors contributing to quantitative phenotypic variation at various organizational levels. Next-generation phenotyping generates precise data and requires novel data management, access and storage systems, increased use of ontologies to facilitate data integration, and new statistical tools for enhancing experimental design and extracting biologically meaningful signal from environmental and experimental noise.
The proposed topic focuses on trait evaluation to gene discovery and its deployment into varieties for drought tolerance through integration of recent knowledge in the fields of eco-physiology, genomics and phenomics.