Climate Stress Affects the Important Phases of Oil Palm Flower Development on Various Soil Types

Abstract Oil palm production is influenced by genetic variation, environmental conditions, particularly climate, and management practices. This study analyzed the time lag effects of climate factors on the number of bunches, average bunch weight (ABW), and oil palm yield across four soil types: Ultisols, Entisols, Spodosols, and Histosols. Conducted in Central Kalimantan, Indonesia, the research covered 12 blocks (1,609.32 ha) and utilized a two-stage cluster sampling method. Data on climate variables, including rainfall, sunshine hours, temperature, humidity, and wind speed, were obtained from meteorological stations and on-site measurements. Monthly averages were analyzed using ANOVA, Duncan’s Multiple Range Test, and regression analysis. The results demonstrated significant relationships between climate factors and oil palm productivity across soil types. Sandy soils (Spodosols and Entisols) experienced earlier, and prolonged climate stress compared to Ultisols and Histosols, with Histosols showing the shortest stress duration. Rainfall emerged as the dominant factor influencing oil palm performance due to its critical role in water availability during key growth phases: anthesis (6–8 months before harvest, MBH), spikelet initiation (18–22 MBH), and spathe initiation (25–30 MBH). Insufficient rainfall during these phases led to reduced flower fertility, lower bunch formation, and decreased fruit set. These findings highlight the need for site-specific climate adaptation strategies to optimize oil palm productivity under varying soil conditions.