Discoloured leaf petioles

Note vein flecking in the leaf petiole caused by banana streak virus.

Banana streak virus

Cause: The banana streak virus (BSV).

Solution: Do not take planting material from infected plants. Eradicate infected plants where symptoms are observed.

Note vein flecking in the leaf petiole caused by banana bunchy top virus.

Banana bunchy top

Biosecurity Alert!

Cause: The banana bunchy top virus (BBTV) which is spread on infected planting material and by the banana aphid, Pentalonia nigronervosa. BBTV is not present in tropical Australia, and movement of planting material is controlled by legislation.

Solution: There is no cure for this disease and all infected plants must be eradicated.

Reporting: Under state legislation, banana bunchy top disease must be reported. If you have seen plants with banana bunchy top symptoms within the Southern Queensland banana biosecurity zone, or the NSW Banana Bunchy Top Virus Control Zone contact the Banana Bunchy Top Hotline on 1800 068 371.

If you have seen banana bunchy top outside of these areas, you must report it within 24 hours to the Biosecurity authority in your state (Biosecurity Queensland on 13 25 23, or NSW DPI Biosecurity Hotline 1800 680 244) or the Exotic Plant Pest Hotline on 1800 084 881.

More Information:
Australian Banana Growers Council
Better Bananas
Department of Agriculture and Fisheries
NSW Department of Primary Industries
Plant Health Australia

Pink discolouration of the petioles first appears on the older leaves but all leaves quickly become affected.

Nitrogen deficiency

Cause: Insufficient nitrogen available for the plant due to inadequate fertiliser applications or leaching and gaseous loss of the nitrogen fertiliser applied.

Solution: Appropriate application of nitrogen fertiliser. You need to know your soil type, climate, past fertiliser program, and soil and leaf analysis results when determining the fertiliser rate.