Screening of seedlings against rust, inoculation treatment and assessment by video image analysis
| MSI99P2144 | |
| Autrey, L. J. C. Moutia, Y. Saumtally, S. | |
| Screening of seedlings against rust, inoculation treatment and assessment by video image analysis | |
| Periodical article | |
| 1996 | |
| Sugar Cane | |
| 1996 (1): 4-10 | |
| En | |
| En | |
| Common rust caused by Puccinia melanocephala H and P Sydow is an important disease of sugar cane under conditions of high humidity and moderate temperatures. As rust affects young cane, it is particularly suited for the screening of clones at an early stage. To further enhance the assessment procedure, it is desirable to conduct the screening on seedlings with a readily available source of spores. With these objectives, experiments were undertaken to determine the feasibility of artificial inoculation of plants with preserved spores and assessing the reaction using a video image analyzer. A vacuum pump arrangement was devised to collect spores from infected leaf surfaces and about 1g of spores could be obtained within a few hours. The spores were stored under various conditions. Maintaining the spores at -80°C or at -196°C in liquid nitrogen at 20-30 per cent humidity, or at -23°C without humidity, were the most appropriate conditions of preservation. Ambient conditions of preservation were the least effective. Estimation of spore concentration for inoculation purposes could be determined by weighing the sieved spores on a precision balance or using a spectrophotometer instead of a haemacytometer. The most appropriate age for plant inoculation was found to be 90 days using a concentration 2.2 x 10 5 spores/ml. A video image analyzer was used to assess percentage leaf area infected and proved to be consistent and accurate. Analysis of data from progeny of bi-parental crosses showed that leaves 1 and 4 (the first leaf with more than 50 percent of its surface unrolled being taken as leaf 1) or leaf 3 alone could well represent the overall infection of the seedlings. The application of these results will allow more rapid screening for rust infection. | |
| SUGARCANE PUCCINIA MELANOCEPHALA SCREENING DIAGNOSTIC TECHNIQUES DISEASES FUNGAL DISEASES VIDEO IMAGE ANALYSIS RUST | |
| MAURITIUS | |
| Sugarcane: Diseases and disease management | |
| Fungal diseases: rust | |
| 1996-04-10 | |
| En | |
| LIB | |
| CAT | |
| 1 | |
| PATH |