coffee rust and its management.pptx

Coffee rust, caused by the fungus Hemileia vastatrix, is a major threat to coffee crops worldwide. It starts with small yellow spots on leaves, growing to orange pustules underneath. These erupt, releasing spores that spread with wind and rain, infecting other leaves. Infected leaves turn brown, drop, and weaken the plant, leading to reduced yields and even death. This devastating disease has historically crippled coffee production in regions like Sri Lanka and Central America.

1. Coffee Rust: A Threat to Coffee Growers Coffee rust is a disease that poses a severe threat to coffee growers worldwide. The coffee crop is constantly exposed to various pests and diseases, including the well-known coffee berry borer, coffee leaf miner, and diseases such as coffee rust and coffee wilt. The impact of coffee rust has been devastating, with significant effects on coffee production in Sri Lanka and beyond. by Sathiya Aravindan

2. Identification and Impact 1 Identification The disease is caused by the fungus Hemileia vastatrix , later renamed as Wardia vastatrix . It was first reported by H.J Berkeley in 1870. 2 Spread and Devastation In the 1970s, coffee rust spread from Africa to Brazil, causing severe devastation. Efforts to contain the spread, such as creating a safety zone, were unsuccessful. 3 Impact on Sri Lanka Coffee rust has had a significant impact on coffee production in Sri Lanka, leading to substantial yield reduction.

3. Systematic Position and Symptomatology Systematic Position Domain: Eukarya Kingdom: Fungi Phylum: Basidiomycota Class: Pucciniomycetes Order: Pucciniales Family: Pucciniaceae Genus: Hemileia / Wardia Species: vastatrix Symptomatology Small, yellow-colored powdery lesions appear on the upper side of the leaves. Severe infections lead to the lesions coalescing and enlarging, turning into orange-colored urediniospores. This results in premature leaf fall and a drastic reduction in yield. Pathogen Morphology Produces asexual spores called Uredionospores and sexual spores called teliospores. Coffee rust is also called the autoecious demicyclic rust.

4. Epidemiology and Management Strategies 1 Epidemiology The spores mainly enter through the stomata and require good rain splash for germination. Temperature between 15 to 28 ℃ is highly conducive for spore germination. 2 Management Strategies Cultural methods include growing resistant varieties and planting seedlings in a well-spaced manner. Chemical methods involve employing Sulphur fungicide, while biological methods use biocontrol agents.

5. Urediniospores and Teliospores 3M Urediniospores Capable of producing 3,00,000 to 5,00,000 spores Millions Teliospores Capable of producing millions of spores

6. Spore Germination and Temperature Spore Germination Spores mainly enter through the stomata and require good rain splash for germination. Optimal Temperature Temperature between 15 to 28 ℃ is highly conducive for spore germination, with 22℃ being the optimal temperature.

7. Resistant Varieties and Seedling Planting Resistant Varieties Growing resistant varieties such as Cauvery to minimize yield loss. Seedling Planting Planting seedlings in a well-spaced manner to avoid dampness and create unfavorable conditions for disease development.

8. Chemical and Biological Methods Chemical Methods Sulphur dusting at the rate of 25kg/ha Biological Methods Employing biocontrol agents such as Darluca filum and Penicillium brevicompactum

9. Devastating Effect and Spread 1 Devastating Effect Coffee rust has caused severe devastation, with significant effects on coffee production. 2 Spread In the 1970s, coffee rust spread from Africa to Brazil, causing widespread damage.

10. Autoecious Demicyclic Rust Autoecious Rust The rust pathogen does not require any other host to complete its life cycle. Demicyclic Rust The rust pathogen completely lacks the uredial stage in its lifecycle, a concept still under investigation.

11. V. Sathiya Aravindan M.Sc., Agri Plant Pathology Annamalai University