> ## Documentation Index
> Fetch the complete documentation index at: https://badixth-dc85e378.mintlify.site/llms.txt
> Use this file to discover all available pages before exploring further.

# Pestalotiopsis / Neopestalotiopsis Leaf Fall in Rubber

> An emerging serious threat to rubber across Malaysia, Indonesia, and Thailand since 2017. Recognition, distinguishing from CLF, and management options.

**Pestalotiopsis / Neopestalotiopsis leaf fall** has emerged as a major threat to Malaysian, Indonesian, and Thai rubber since around 2017. In Indonesia, it has caused catastrophic latex losses (estimates of 20 to 45% yield reduction in outbreak areas). Symptoms overlap heavily with [Corynespora leaf fall](/guides/Crop/Rubber/biotic/diseases/corynespora), so ground confirmation is essential for species-level diagnosis.

## Cause

* *Neopestalotiopsis cubana* and related *Pestalotiopsis* species
* **High humidity** and warm temperatures
* **Continuous rain** during refoliation
* **Clonal susceptibility** (still being characterized; many clones affected)
* **Cross-border spread** from Indonesia and Thailand into Malaysia

## Effect

| Stage    | Symptom                                                        |
| -------- | -------------------------------------------------------------- |
| Early    | Small tan-brown spots (1 to 3 mm) with grey-white centers      |
| Mid      | Spots may develop "shot-hole" or needle-hole appearance        |
| Late     | Whole-leaf blight, premature leaf fall out of wintering window |
| Terminal | Repeated defoliation, severe canopy loss, latex flow crash     |

How to distinguish from CLF:

* Pestalotiopsis lesions are typically **smaller** with **grey-white centers**
* CLF has larger lesions with **fishbone/railway veinal patterns**
* Both cause out-of-season leaf fall; laboratory confirmation is the only certain method

## Satellite signals

Same pattern as CLF: out-of-season NDVI drop and delayed refoliation. Satellite cannot distinguish the two; ground diagnosis required.

## Action

<Steps>
  <Step title="Send samples for identification">
    Contact the Malaysian Rubber Board (MRB) for confirmation. Symptoms mimic CLF; laboratory identification is required. Report to MRB regardless (regulatory tracking).
  </Step>

  <Step title="Fungicide options (research ongoing)">
    Current best options include **hexaconazole**, **propiconazole**, and **mancozeb** on immature trees. Effectiveness is variable; follow current MRB advisories.
  </Step>

  <Step title="Reduce tapping intensity">
    Same principle as CLF: allow refoliation, do not compound stress with over-tapping.
  </Step>

  <Step title="Monitor spread">
    Track new outbreaks; report to MRB to support regional surveillance.
  </Step>
</Steps>

## Recommended alert settings

Same as CLF (same satellite signature). Distinguish species by ground diagnosis.

| Trigger                 | Condition                                                   | Severity |
| ----------------------- | ----------------------------------------------------------- | -------- |
| Out-of-season NDVI drop | -0.10 sustained 14 days outside Feb-Apr window              | High     |
| Regional advisory       | MRB or IRRDB outbreak advisory triggers heightened scouting | High     |

## Related

* [Corynespora leaf fall](/guides/Crop/Rubber/biotic/diseases/corynespora)
* [Powdery mildew](/guides/Crop/Rubber/biotic/diseases/powdery-mildew)
* [Rubber ecosystems (wintering baselines)](/guides/Crop/Rubber/rubber-ecosystems)