| Popis: |
This review addresses possible adaptation strategies in rice production to abiotic stresses that will aggravate under climate change: heat (high temperature and humidity), drought, salinity, and submergence. Each stress is discussed regarding the current state of knowledge on damage mechanism for rice plants as well as possible developments in germplasm and crop management technologies to overcome production losses. Higher temperatures can adversely affect rice yields through two principal pathways, namely (i) high maximum temperatures that cause—in combination with high humidity—spikelet sterility and adversely affect grain quality and (ii) increased nighttime temperatures that may reduce assimilate accumulation. On the other hand, some rice cultivars are grown in extremely hot environments, so that the development of rice germplasm with improved heat resistance can capture an enormous genetic pool for this trait. Likewise, drought is a common phenomenon in many rice growing environments, and agriculture research has achieved considerable progress in terms of germplasm improvement and crop management (i.e., water saving techniques) to cope with the complexity of the drought syndrome. Rice is highly sensitive to salinity. Salinity often coincides with other stresses in rice production, namely drought in inland areas or submergence in coastal areas. Submergence tolerance of rice plants has substantially been improved by introgressing the Sub1 gene into popular rice cultivars in many Asian rice growing areas. Finally, the review comprises a comparative assessment of the rice versus other crops related to climate change. The rice crop has many unique features in terms of susceptibility and adaptation to climate change impacts due to its semiaquatic phylogenetic origin. The bulk of global rice supply originates from irrigated systems which are to some extent shielded from immediate drought effects. The buffer effect of irrigation against climate change impacts, however, will depend on nature and state of the respective irrigation system. The envisaged propagation of irrigation water saving techniques will entail benefits for the resilience of rice production systems to future droughts. We conclude that there are considerable risks for rice production stemming from climate change, but that the development of necessary adaptation options can capitalize on an enormous variety of rice production systems in very different climates and on encouraging progress in recent research. |
