Explore key diseases affecting coconut palms and learn to identify symptoms, management practices, and pathogens. Sharpen your agricultural expertise on coconut disease control and prevention.
What is the primary symptom of coconut leaf blight caused by Helminthosporium species?
Explanation: Helminthosporium leaf blight primarily manifests as brown necrotic spots with surrounding yellow halos on the leaves. White powdery patches are characteristic of powdery mildew, not leaf blight. Stem bleeding with reddish exudate refers to a different disease involving the trunk, and wilting of the crown without spots may indicate root wilt disease or drought stress.
Which fungal pathogen is mainly responsible for causing bud rot in coconut palms?
Explanation: Phytophthora palmivora is well known for causing bud rot in coconuts, especially during wet, humid conditions. Ganoderma lucidum is associated with basal stem rot, Colletotrichum gloeosporioides causes anthracnose, and Fusarium oxysporum primarily leads to fusarium wilt in various crops.
For reducing the occurrence of stem bleeding in coconut plantations, what is a recommended management practice?
Explanation: Applying Bordeaux paste helps manage stem bleeding by preventing further fungal spread through wounds. Spraying pyrethrin targets insect pests, not fungal diseases. Mowing close to trunks increases risk of mechanical damage, and excessive irrigation can worsen disease conditions rather than prevent them.
Which environmental condition most favors the development of leaf blight in coconuts?
Explanation: Leaf blight fungi proliferate in environments with high humidity and frequent rainfall, as moisture enables spores to germinate and infect leaves. Drought and strong sunlight typically deter disease development. Low temperatures and frost are not common in coconut-growing regions, while sandy soil affects nutrition rather than direct disease development.
If a coconut palm displays sudden yellowing and wilting of the entire crown, which disease is most likely involved?
Explanation: Sudden yellowing and wilting of the entire crown is a typical sign of root wilt disease in coconuts. Helminthosporium leaf spot presents as smaller lesions, black band disease is rare and affects roots, and pink disease causes fungal growth on branches and exudates but not widespread crown wilting.