Breeding for Climate Change in Sub-tropical Australia
Climatic conditions in Australias principal mandarin growing region have changed dramatically over the last four decades, and there is no sign that the rate of wanning has yet peaked. For almost 100 years this region had an annual growing season (10 year rolling average) of～2 800 Heat Units (HU) , but HU have increased since -1970 to over 3 100 annually and at the current rate of increase could be more than 3 300 HU within 20 years. The three hottest seasons since 1870 have occurred in the last decade. In the subtropics, these changes mean that varieties now mature earlier, some prior to the onset of cool autumn conditions, resulting in poorer external colour development. The winter conditions necessary to induce flowering in spring have also changed. To keep ahead of climate change, Queensland s breeding program is located more than 150 km from the commercial production area at a site which has wanner temperature profiles particularly during the critical seasons of autumn and winter. The location of this breeding program not only ensures faster growth and fruiting of hybrids, but also increases the likelihood of selecting new varieties that can develop strong colour and be as productive, as the commercial production area continues to warm. We will show that by breeding at a site with wanner autumn and winter temperatures, it should be possible to stay more than 20 years ahead of our predicted rate of climate change in the commercial production area. To date, 52 000 progenies have been generated in this program using a range of strategies including triploidy, irradiation and conventional diploid crossing. Some 340 hybrids have been selected based on fruit quality, and of these five have progressed through multi-year assessment and taste panels to semi-commercial evaluation. Varieties from this breeding program now dominate new commercial plantings, and it is expected that future releases will offer industry superior germplasm that is adapted to the subtropics and resilient in the face of ongoing climate change.
Citrus reticulata Temperature Skin colour
Malcolm W. Smith Debra L. Gultzow Toni K. Newman John C. Chapman Helen J. Hofman Timothy V. Johnson
Horticulture and Forestry Sciences, Department of Primary Industries and Fisheries, Bundaberg Research Station,4670, Queensland, Australia
国际会议
11th International Citrus Congress(第11届国际柑橘大会)
武汉
英文
404-409
2008-10-01（万方平台首次上网日期，不代表论文的发表时间）