Inheritance of rust resistance and breeding strategies at the Mauritius Sugar Industry Research Institute
| MSI01P3526 | |
| Ramdoyal, K. Saumtally, S. | |
| Inheritance of rust resistance and breeding strategies at the Mauritius Sugar Industry Research Institute | |
| 6th ISSCT Breeding Workshop, Barbados, 13-17 November 2000 | |
| Conference paper | |
| 2001 | |
| Sug. Cane Int. | |
| (Feb. 2001) : 22 | |
| Abstract only. Published in: Abstracts, 6th ISSCT Breeding Workshop, 13-17 November 2000, Barbadosp. p. 10-11 | |
| En | |
| En | |
| Common rust (Puccinia melanocephala H and P Syd.) is considered as a major disease of sugar cane in humid and very humid environments of Mauritius, covering about 45 per cent of the acreage under cane cultivation. The disease became prevalent in several commercial varieties in 1978 and in the 1980's and cane yield losses of 8-11 per cent were recorded on varieies M 555/60, M 2370/62 and M 1030/71 in trials. The systematic screening of promising varieties for their reaction to rust was established in final phase trials as from 1991. In an attempt to increase productivity particularly in the very humid areas and where cane cultivation has recently been extended to the former tea lands, the programme directed crosses and site specific selection was intensified . It became necessary to incorporate rust resistance to segregating populations that would be evaluated in these areas. The inheritance of rust resistance was studied in sugar cane seedling populations using a factorial mating design over one summer and two winter seasons to guide breeding strategies. Frequency distriutions for rust infection showed that resistant (R) x resistant parents produced the majority of progenies in the resistant classes whereas susceptible parents produced a high percentage of susceptible ones. Distributions of infection within the selfed resistant parent R 570 and in the majority of the crosses tented to support a major gene hypothesis with a dominant effect for resistance. The segretation pattern also suggested the effect of minor genes acting in a quantitative way. Female (F) and male (M) parents differed significantly for their reaction to rust and F x M interactions also indicated the existence of non-additive effects. F x season (S), M x S, and F x M x S interaction mean squares were generally low. Broad-sense heritability for individual season rating and combined rating (0.75-0.90) were high suggesting the trait to be highly repeatable. Susceptible families and / or susceptible clones cane be effectively eliminated from segregating populations in rust-prone areas early in the selection programme. Narrow-sense heritability was moderate (0.40-0.52) with additive genetic effects accounting for 44-68 per cent of total genetic variation. Computer-aided crossing lays emphasis on resistant and slightly susceptible parents but the limited availability of these categories of parents may necessitate the use of crosses between resistant and susceptible parents but the limited availability of these categories of parents may necessitate the use of crosses between resistant and susceptible parents. The first clonal stage is now being screened for rust susceptibility prior to the selection of clones for rust prone areas. Concurrently, at this stage, crosses are screened from databases, on the basis of their parent reaction before channelling to the humid areas. This philosophy corroborates with various stations which screen for rust as from the early selection stages | |
| Rust diseases Sugarcane Diseases Puccinia melanocephala inheritance breeding disease resistance | |
| Mauritius | |
| Sugarcane | |
| Diseases | |
| 2001-01-15 | |
| En | |
| LIB | |
| CAT | |
| PB Path |