In Europe, rice (467 000 ha) is grown under permanently flooded (PF) conditions using irrigation waters of major rivers. Climate change, which already induces decrease in the river flows, threatens rice yields by scarcer water availability. In addition, PF rice fields emit greenhouse gases (GHG), mainly methane (CH4), that have a very strong warming potential.
Alternative wetting and drying (AWD) is a system based on “intermittent” irrigation” in which fields are allowed to dry out for a short period before being reflooded again. It is estimated that water input can be reduced by 15-30% with no loss in yield and that GHG emissions will be reduced by up to 48 %. AWDS represents therefore an interesting alternative for European rice production.
The main objective of GreenRice is to test AWDS in European rice crop, so that experiments will be conducted in Italy, Spain and France.
We will evaluate the implications of shifting from a PF to an AWD system on rice environment and productivity. To this end, the following topics will be studied:
- Changes on environmental elements such as water consumption, soil salinity, soil microbial community, GHG emission, soil chemistry, and arbuscular mycorrhizal (AM) colonization
- Varieties that maintain their productivity under AWD through whole genome association mapping of a large panel of temperate varieties. The bases for marker-aided breeding using genomic selection to predict the values of additional breeding lines will be set.
- Traits determining rice plant adaptation to AWD such as root development, AM colonisation, salinity tolerance and resistance to nematodes using the same large panel of European genotypes
- AM symbiosis for the alleviation of biotic stress (blast) An extensive gene expression study will identify the root types and genes of major importance in transport process and the degree to which they are affected by AWD.
- The role of plant traits and the soil microbial community in modulating GHG and cycling of C and N.
The results obtained will be disseminated to the local stakeholders (farmers and natural parks and spaces, mainly) and to the scientific community (through web site, database and publications). Scientists specialized in molecular genetics, functional genomics, phytopathology, agronomy, ecology, and bioinformatics from 7 institutions of 4 countries will be involved.