MSI99P1056 | |
Autrey, L. J. C. Moutia, Y. Médan, H. | |
Video image analysis: a tool for the sugar cane pathologist for the assessment of varietal reaction to rust disease | |
3rd ISSCT Sugar Cane Pathology Workshop, Mauritius, 22-26 July 1991 | |
Conference paper | |
1991 | |
Abstract in Sug. Cane 1992 (1): 29-30 | |
En | |
EN | |
Infection by rust (Puccinia melanocephala) was determined in seedlings issuing from a biparental cross between Q96, a susceptible variety, and M1030/71, a highly susceptible variety. The seedlings were inoculated at the five-leaf stage with a rust suspension of 1 x 10 5 spores/ml. Infection was measured three weeks later by video image analysis with an imaging system from Seescan plc, UK. Seventy-four seedlings, bearing 5-7 leaves, and taken at random from the 200 which had been infected, were screened. The area infected per leaf reached 86 per cent and was greatest on the third leaves, taking the youngest leaf of a shoot as leaf 1. Total leaf area/seedling infected ranged from 0 to 35 per cent, being 10-20 per cent on two-thirds of the plants. Comparison of infection of individual leaves with overall leaf infection showed that the extent of infection on leaves 3 and 4 best reflected the extent of overall infection. The correlation between these parameters was shown by linear regression (r=0.794), while in the range 0 - 30 per cent infection of leaves 3 and 4, better correlation (r=0.838) was obtained by quadratic regerssion. Further work is being done to ascertain if the correlations hold outside the range of infection obtained in the experiment. The apparatus will be used for varietal screening and studies on quantitative genetics on rust and other diseases, especially yellow spot, which is a limiting factor to production in the wet uplands of Mauritius. The device is particularly useful with diseases like rust, for which visual assessment of infection, especially on seedlings, is unreliable. | |
SUGARCANE RUST DISEASES ANALYTICAL METHODS PUCCINIA FUNGAL DISEASES DISEASES PUCCINIA MELANOCEPHALA | |
MAURITIUS | |
Sugarcane: Diseases and disease management | |
1992-07-15 | |
En | |
Mauritius Sugar Industry Research Institute | |
PATH |