Response of Brassica napus and B. juncea germplasm from Australia, China and India to Australian populations of Leptosphaeria maculans
Germplasm from Australia, China and India was screened for resistance to blackleg (phoma stem canker), caused by Leptosphaeria maculans, under Australian field conditions. More than half of the world’s races of L. maculans occur in Australia, and sites were chosen to encompass areas of high race diversity. Plots were sown into the previous season’s L. maculans-infested residues. Significant differences in response were observed among genotypes of both Brassica napus and B. juncea when tested in Victoria, South Australia and Western Australia. Significant differences in response were observed among B. juncea, but not B. napus genotypes, when tested in New South Wales. Differences in the relative degree of expression of host resistance were observed between some test sites in relation to Australian cultivars that either contained major gene-based resistance (e.g. Surpass 400) or those that effectively had only polygenic resistance (e.g. AV-Sapphire, Lantern, Monty, Rainbow and Trigold). Australian genotypes, especially of B. napus, are generally more resistant than the Chinese and Indian genotypes. The majority of the B. juncea genotypes from both China (e.g. Xinyou 5) and India (e.g. Rohini) showed a high level of resistance, while some B. napus genotypes (e.g. 04-P34, P617 and P624 from China) showed at least a low level of resistance. Promising Australian B. napus germplasm in particular may provide high levels of polygenic resistance to both India and China should the disease become established in one or both those countries.
KeywordsAustralasian Plant Pathology Plant Survival Susceptible Genotype Western Australia South Australia
Unable to display preview. Download preview PDF.
- Anon. (2004) Blackleg resistance breakdown in canola varieties containing ‘sylvestris’ resistance. National Recommendations for 2004. Canola Association of Australia and Oilseeds Western Australia, Miscellaneous Bulletin. 2 pp.Google Scholar
- Fitt BDL, Hu BC, Li Z, Liu S, Lange RM, Kharbanda PD, White RP (2007) Strategies to prevent spread of Leptosphaeria maculans (phoma stem canker) onto oilseed rape crops in China. In ‘Proceedings of the 12th International Rapeseed Congress, Wuhan, China. Vol. IV’. (Eds T Fu, C Guan) pp. 28–31. (Science Press USA Inc.: Monmouth Junction, NJ)Google Scholar
- Gororo N, Salisbury P, Marcroft S (2004) Dunkeld and Rainbow: a tale of two Victorian canola cultivars. In ‘Proceedings of the 4th International Crop Science Congress, Brisbane, Queensland, Australia’. Available at http://www.regional.org.au/au/cs/2004/poster/3/7/3/975_gororo.htm [Verified 14 January 2008]Google Scholar
- Hua Li, Barbetti MJ, Sivasithamparam K (2003) Responses of Brassica napus cultivars to Leptosphaeria maculans field isolates from Western Australia. Brassica 5, 25–34.Google Scholar
- Hua Li, Damour L, Barbetti MJ, Sivasithamparam K (2004) Increased virulence and physiological specialization among Western Australian isolates of Leptosphaeria maculans breaking down existing single dominant gene-based resistance in six cultivars of Brassica napus. Brassica 6, 9–16.Google Scholar
- Hua Li, Smyth F, Barbetti MJ, Sivasithamparam K (2006) Relationship in Brassica napus seedling and adult plant responses to Leptosphaeria maculans is determined by plant growth stage at inoculation and temperature regime. Field Crops Research 96, 428–437. doi: 10.1016/j.fcr.2005.08.006CrossRefGoogle Scholar
- Sivasithamparam K, Barbetti MJ, Hua Li (2005) Recurring challenges from a necrotrophic fungal plant pathogen: a case study with Leptosphaeria maculans (causal agent of blackleg disease in Brassicas) in Western Australia. Annals of Botany 96, 363–377. doi: 10.1093/aob/mci194CrossRefPubMedGoogle Scholar
- Thomas V, Salisbury P, Norton R, Marcroft S (2007) The current situation in the Brassica juncea—Leptosphaeria maculans pathosystem and how future changes will be monitored. In ‘Proceedings of the 12th International Rapeseed Congress, Wuhan, China. Vol. IV’. (Eds T Fu, C Guan) pp. 213–216. (Science Press USA Inc.: Monmouth Junction, NJ)Google Scholar