Impact of Genetic Improvements of Rice on Its Water Use and Effects of Climate Variability in Egypt

Abstract

Developing and disseminating resilient rice cultivars with increased productivity is a key solution to the problem of limited natural resources such as land and water. We investigated trends in rice cultivation areas and the overall production in Egypt between 2000 and 2018. This study identified rice cultivars that showed potential for high productivity when cultivated under limited irrigation. The results indicated that there were significant annual reductions in both the rice-cultivated area (−1.7% per year) and the production (−1.9% per year) during the study period. Among the commonly cultivated varieties, Sakha101 showed the highest land unit productivity, while Sakha102 showed the highest water unit productivity. The impact of deploying new cultivars was analyzed by substitution scenarios. The results showed that substituting cultivars Giza179 and Sakha107 has the potential to increase land productivity by 15.8% and 22.6%, respectively. This could result in 0.8 million m3 in water savings compared to 2018 water consumption. Long-term impacts of climate variability on the minimum and maximum temperature, relative humidity, and average precipitation during on- and off-season for rice productivity were also analyzed using an autoregressive distributed lag (ARDL) model. The results indicated that climate variability has an overall negative impact on rice productivity. Specifically, minimum temperature and on- and off-season precipitation had major long-term impacts, while higher relative humidity had a pronounced short-term impact on rice yields. The study revealed that short-duration cultivars with higher yields provided greater net savings in irrigation resources. These analyses are critical to guide the development of strategic management plans to mitigate short- and long-term climate effects on overall rice production and for developing and deploying improved rice varieties for sustainable rice production.

Molecular Genetic Diversity and Combining Ability for Some Physiological and Agronomic Traits in Rice under Well-Watered and Water-Deficit Conditions

“…Consequently, it is vulnerable to reduced yields due to water scarcity [ 9 ]. Thus, developing drought-tolerant genotypes is imperative in order to maintain global food security [ 10 , 11 ]. Continuous efforts are underway to breed high-yielding and drought-tolerant rice genotypes, particularly in the face of current climate change.…”

Detection of Superior Rice Genotypes and Yield Stability under Different Nitrogen Levels Using AMMI Model and Stability Statistics

“…Grain yield (GY) is the economic determinant of the best-performing genotypes [ 8 ]. GY is a quantitative trait determined by the additive main effect of environment (E) and genotype (G) in addition to the nonadditive effect of the G X E interaction (GEI) [ 9 ].…”

Physiological and Multi-Omics Approaches for Explaining Drought Stress Tolerance and Supporting Sustainable Production of Rice

“…The evolution and production of drought tolerant rice varieties are developed by understanding the molecular mechanisms and signal responses initiated by tolerant cultivars under water deficit conditions. This approach does not mean that the traditional germplasm or breeding line selection process does not play an important role in this process of developing new rice varieties, some of which could have desirable traits such as short duration with higher yield (Mehana et al, 2021). However, the underlying molecular mechanism must be understood at a holistic level, and therein omics tools are needed and are prominent.…”