Screening Rice Root Growth Under Mechanical Impedance. Final Technical Report.
The project purpose was Screening method for rice varieties with good pan penetration in place (in IRRI, a target institution). The project addressed the developmental problem of low yields in rainfed rice due to strong soil. In rainfed lowland and upland rice, drought is a major cause of low yields. While deep rooting is known to increase drought resistance, this can be affected by mechanically strong soil. Different techniques for screening the ability of rice root systems to penetrate mechanical barriers were developed, tested and compared. Comparisons were also made with results from fields where hardpans were present. In collaboration with Dr. Adam Price (R6673: Drought resistance in upland rice: genetic analysis and varietal improvement), the root penetration ability of a population of recombinant inbred lines was studied in order to identify quantitative trait loci (QTLs) controlling root penetration. The two main outputs of the project were: (1) an improved wax layer method for measuring root penetration ability in rice in either simulated upland or lowland conditions and (2) the identification of QTLs controlling root penetration ability in upland rice. These outputs contribute to DFID's development goals by giving methods and results that plant breeders can use. New varieties with better root penetration of strong soil would be more drought resistant in rainfed rice-growing environments.