Resistance screening of promising sugarcane clones to two races of gumming disease bacterium
| MSI10P4466 | |
| Dhayan, S. Saumtally, A. S. | |
| Resistance screening of promising sugarcane clones to two races of gumming disease bacterium | |
| periodical article | |
| 2010 | |
| Proc. int. Soc. Sug. Cane Technol. | |
| 27: 8 p. | |
| En | |
| En | |
| Two races of the gumming disease bacterium (Xanthomonas axonopodis pv. vasculorum), Races 1 and 2, commonly infect sugarcane varieties in Mauritius. Clones selected from the 3rd clonal stage (years 4-5) of the breeding program are screened for resistance to these two races. From 1998 to 2007, 878 clones were tested in disease resistance trials in localities where the races are prevalent. Inoculated spreader rows of a susceptible variety act as the source of inoculum for the test varieties. Evaluation to Race 1 was carried out at one site; whereas, testing against Race 2 was conducted at two to four sites. Screening showed that 99 per cent of clones were immune to Race 1. Of the 9 clones that showed infection, seven were classified as resistant, one slightly susceptible and one susceptible. In contrast, the percentage of clones showing immunity to Race 2 was much lower (14 per cent). Resistance, slight susceptibility, susceptible, and high susceptibility to Race 2 were 44 per cent, 23 per cent, 13 per cent and 6 per cent, respectively, among the remainder of the clones. Ratings were consistent across locations for 78 per cent of clones. Evaluation at more than one site was consequently justified. The pathogen was isolated from commercial fields in regions prone to the disease and in germplasm collections during the period 1998-2007. Race characterisation was based on cultural characteristics and pathogenicity tests. Race 1 was readily recovered in noble cane collections. Apart from one instance in 1998, it was absent in commercial fields. These surveys confirmed that commercial varieties were highly resistant to Race 1 and, therefore, of insignificant importance in Saccharum hybrids. Gumming disease prevalent in plantations was therefore almost exclusively caused by Race 2. This race was predominant and resistance screening against it in different environments is necessary. | |
| Sugarcane diseases disease resistance gumming disease Xanthomonas axonopodis pv. vasculorum bacterial diseases | |
| Mauritius | |
| Sugarcane: Diseases and disease management | |
| Bacterial diseases: Gumming | |
| 2010-03-17 | |
| EN | |
| LIB | |
| CAT | |
| Path |