Budrot in cococnut

Pathology -jcharleswesley

1. BUDROT IN COCONUT -J Charles wesley(URK17AC200)

2. Systemic position-phytophthora palmivora Kingdom : Fungi Phylum : Heyerokontophyta Class : oomycota Order : Peronosporales Family : Peronosporacae Species : P.palmivora

3. Pathogen and its characters Drooping of successive leaves and falling of leaves one by one, leaving only mature leaves in the lower whorls at the crown Sporangiophores are hyaline and simple or Branched occasionally. The sporangia are hyaline thin walled pear shaped with prominent papillae ,the sporangia releases reniform Biflagellate zoospores upon germination. The fungus also produces thick walled spherical oospores in addition thick walled,yellowish brown chlamydospores are also produced.

4. Favourable conditions: High rainfall, atomspheric Humidity(above 90%),low temp.(18-20°c)and wounds caused by Tappers and Rhinocerous beetles.

5. Mode of speard and survival The fungus remains as dormant mycelium in the infected tissues and also survives as Chlamydospores and Oospores in crop residues in soil. The disease spread is mainly through Air borne sporangia and zoospores. Rainfall also helps in spreading the disease.

6. Symptoms: The earlier symptom is the yellowing of one or two younger leaves . Blackspots appear on spindle leaves Basal tissue of the leaf rots quickly and can be easily separated from the crown. In later stages the spindle withers and drops down. The tender leaf base and soft tissue of the crown will rot into a slimy mass of decayed material emmiting foul smell.

7. Symptoms Ultimately the entire crown falls down and the palm dies. In adult palms,the first visible symptom is the coloured change of the spear,which becomes pale and breaks at the base and hangs down. The rotting slowly prgresses downwards,finally affecting the meristem and killing the palms. This is accompanied by drooping of successive leaves.even then nuts that are retained on the palm may grow to maturity.

8. Pale leaf Drooping

9. Leaf rot

10. Management: CHEMICAL METHOD: Remove all the affected tissue of crown region and crown drenching with Copper chloride 0.25%.Apply Bordeaux paste and protect it from rain till normal shoot emerges. The infected tissues from the crown region should be removed and dressed with Bordeaux paste sprayed with 1%Bordeaux mixture as pre-mansoon spray .(may-sep)

11. Leaf axil filling with sevidol 8G,25g mixed with 200g sand is recommended to red palm weevil infestication of affected plams. Spray with Copper oxychloride 0.25% after the onset of mansoon. Thank you..