Biotechnology to Improve Rice Breeding Techniques (March 2007)

Darvey, N Zhoa, X

2007

This RIRDC report presents the findings from the one year project on biotechnology to improve rice breeding. The report the outlines the project results which aimed at improving the microspore culture technology, which can produce genetically uniform double haploid (DH) plants in one generation from crosses between selected parent lines. The progress in incorporation of cold tolerance from Chinese germplasm into Australian rice is also reported. The objectives of the project were to improve breeding efficiency as well as cold tolerance rice microspore culture enabled DH plant production technology, which was incorporating cold tolerance from Chinese germplasm. Experiments were undertaken in glasshouses using the methods of hydroponics to grow the experimental material. Improvements in plants regeneration from MC derived callus was achieved via modifications to the callus induction and regeneration media which led to improvements in callus quality and the frequency of regeneration. To investigate cold tolerance for 4 days at Panicle initiation stage the rice germplasm and segregating populations derived from different crosses were subjected to a low temperature treatment at 12 – 14°C. Cold tolerant germplasm and individual plants were selected for crossing and backcrossing. A two-step induction culture medium has improved callus quality and plant regeneration. Some DH plants have been produced.  The key findings included four Chinese varieties demonstrated strong cold tolerance under our testing conditions. These varieties have been crossed with Australian varieties. Some cold tolerant F2 plants have been selected for backcrossing to ‘Doongara’. The hybrids of the crosses have being processed for DH plant production.