DISEASES OF SAFFLOWER – Agricultural study materials

1. RUST- Puccinia carthami

Symptoms

The pustules (uredosori) are chestnut brown in colour and scattered throughout the leaves. Later, black teliosori are formed on the leaves. Stem girdling occurs in older plants and rust pustules also appear on roots. Uredia and telia are produced on safflower plants.

Mode of spread 

Spreads through wind borne uredospores

Survival

    The pathogen is an autoceious rust and survives in the infected plant debris

Epidemiology

Cloudy weather favour the disease

Management 

• Remove and destroy the plant debris in soil
• Crop rotation with non-host plant
• Spray mancozeb @ 1 kg/ha
• Grow resistant varieties like APPR 1, 3, PCM 1, 2, and PCN 1

2. LEAF SPOT- Cercospora carthami

Symptoms

Round, brown spots appear on the lower leaves with sunken centre and irregular yellow border. The affected tissues disintegrate and holes are formed between the veins

Mode of spread 

The pathogen spreads through air borne conidia

Survival

Survives as externally seed borne inoculum

Epidemiology

High humidity encourage the disease

Management

• Remove and destroy the plant debris in soil
• Seed treatment with thiram or captan at 4 g/kg of seed
• Spray mancozeb @ 1 kg/ha

3. LEAF BLIGHT-Alternaria carthami

Symptoms

Minute brown to dark brown spots with concentric rings appear initially, expand gradually causing irregular lesions. The centre of the spot is light brown with a dark brown margin

Mode of spread and survival

The pathogen spreads through air borne conidia and survives as externally seed borne inoculum

Epidemiology

High humidity favour the disease

Management

• Seed treatment with thiram or captan at 4 g/kg of seed
• Spray mancozeb @ 1 kg/ha
• Grow disease tolerance varieties like NS 133, 1015, 1016, 1021, and EC 32102.