Diseases of Fruit Plantation Medicinal and Aromatic Crops

Bird's eye spot

Causal organism: Helminthosporium heveae Petch.
Symptoms

• Affected rubber leaves have numerously-scattered small, circular spots with transparent centers and distinct brown borders which look like bird’s eye.
• Young leaves are blackened and wrinkled, older leaves have necrotic lesions that result formation of shot holes caused due to falling down of tissue.
Etiology

• In culture, growth of this fungal pathogen is cottony white which turns light brown at a later stage.
• Conidiophores are single or clustered, tall, brown; stomata often present; conidia develop laterally through pores beneath septa while apex conidiophore is still growing, often appearing in whorls, single, subhyaline to brown obclavate, pseudoseptate with prominent basal scar; conidia measures 65-170 x 9.5-10 mm with 3-6 septations under 100x.
Management

• Spraying Bordeaux mixture (1%) or Mancozeb (0.25%)
• Provide shades to the nursery.