Small temperature variations are a key regulator of reproductive growth and assimilate storage in oil palm (Elaeis guineensis)

Oil palm is an important crop for global vegetable oil production, and is
widely grown in the humid tropical regions of Southeast Asia. Projected
future climate change may well threaten palm oil production. However, oil
palm plantations currently produce large amounts of unutilised biological
waste. Oil palm stems – which comprise two-thirds of the waste - are
especially relevant because they can contain high levels of non-structural
carbohydrates (NSC) that can serve as feedstock for biorefineries. NSC in
the stem are also considered a potent buffer to source-sink imbalances. In
the present study, we monitored stem NSC levels and female reproductive
growth. We then applied convergent cross mapping (CCM) to assess the
causal relationship between the time-series. Mutual
causal relationships between female reproductive growth and stem NSC were
detected, with the exception of a relationship between female reproductive
organ growth and starch levels. NSC levels were also influence by
long-term cumulative temperature, with the relationship showing a
seven-month time lag. The dynamic between NSC levels and long-term
cumulative rainfall showed a shorter time lag. The lower temperatures and
higher cumulative rainfall observed from October to December identify this
as a period with maximum stem NSC stocks.