Spatiotemporal Green Canopy Dynamics and Plantation Resilience: Climate, Disease, and Yield Interactions in Rubber Ecosystems

Tropical rubber plantations follow a predictable monsoon-driven cycle of leaf flush during the dry season and leaf drop with the onset of rains. Rising frequency of Pestalotiopsis fungal outbreaks and increasing climate variability are disrupting this phenology, yet the combined effects on canopy health, climate, and latex yield have not been fully quantified. This study aims to (1) map spatiotemporal trends in canopy greenness and identify zones of seasonal gains or losses, (2) quantify how Pestalotiopsis outbreaks, climate variables, and clone identity drive defoliation severity, and (3) establish the temporal lag between canopy condition and latex yield. Harmonized Landsat Sentinel-2 from 2017 through 2024 were processed to derive monthly green canopy cover (GCC). The Seasonal-Trend Decomposition isolated trend, seasonal, and residual signals. Seasonal Mann-Kendall tests identified areas with significant canopy changes. A linear mixed-effects model linked GCC to outbreak status, climate variables, and clone type, with block as a random effect. Cross-correlation revealed GCC increases typically preceded latex yield gains by 1–2 months. Pestalotiopsis outbreaks after 2018 caused deeper, prolonged canopy loss than natural cycles. Spatial trends showed central blocks improved, while edges declined. The model explained over 80% of GCC variation, highlighting heat stress and rainfall as key disease amplifiers. Resistant clones like RRIC 100 and IRR 112 retained canopy better, and mixed-clone plantings buffered defoliation. Results emphasize genetic diversity's role in resilience and the need for zone-specific management based on spatial canopy trends and outbreak-linked climate thresholds.