In the past week you may have noticed dead leaves in your young SRA36 cane crops. Dr. Rob Magarey (SRA Pathologist), HCPSL Company Manager- Lawrence Di Bella, SRA plant breeding team members Dr. Fengduo Hu, Juan Briceno and Linda Di Maggio spent Wednesday the 16th of November in the field inspecting blocks of SRA36 across the district.

On inspecting impacted fields, it was noted a physical damage of the top uncurled top leaves of SRA36 was present; often in the 3rd uncurled leaf. The damage consisted of leaf senescence and yellowing of the tissue of the leaf blade, occurring as a stripe in one or both sides of the midrib, and other times the whole leaf blade. No callus or necrotic line separating live tissue from dead tissue was observed, ruling out a reaction of the plant to a pathogen or parasite. New leaves continue to grow unaffected in the inspected canes; the new leaves and the whole plant did not show any signs of further damage.

Above: Note the yellow senescence on the leaf in a cane stool.
Above: Note the 3rd unfolded leaf that has yellow senescence.

The senescence of the leaves in the SRA36, was due a climatic event that occurred 3 weeks earlier. At that time a number of high dew mornings and fog, followed by high daily temperatures up to 40 degrees Celsius in field occurred, with an actively growing crop making it an ideal situation for crop damage. In this particular situation, the soft leaf tissue in the growing point had water present (due to the fog) and the high temperatures experienced during the day caused the plant tissue cells to become damaged. As the plant continued to grow these damaged leaves elongate and become fully unfolded exposing the damaged leaves.

It is anticipated that no yield loss will occur, and the variety will continue to grow to its full potential.

If you see anything usual in the field at any time, please contact HCPSL on 47761808.