Cyclones are occurring, more or less frequently, in most coconut producing countries. For instance, in the 1990s, extreme weather cost the Pacific region more than 1 billion USD (Asian Development Bank, 2013).
The way coconut palms are destroyed seems to
depend on the nature of the soil: broken stems in rocky
and compact soils, uprooting in sandy and soft soils. From an economic and
agricultural point of view, it seems that the damages and loss of production
induced by cyclones are more important than the killing of palms, often
occurring only close to the cyclone eye.
Such climate disasters can threaten human and
animal lives. One of the worst coconut-related stories was recorded in 1878 on the
Kaukura atoll in the Tuamotus, French Polynesia. Copra
harvesters were surprised by the storm during the seasonal occupation of a motu.
The cyclone killed 117 people.
The coconut palm rather evokes exotic images of quiet beaches. But sometimes the figth between the trees and the ocean sometimes said to be "Pacific" becomes of a great violence. The coconut palms uprooted resemble then soldiers given up on a battle field. This image was carried out in Micronesia, on the atoll of Funafuti, in its part the most exposed to the tropical storms and cyclones. These are the same storms which disseminate the seeds of coconut palm from islands to islands. It is clear that in such an ecology, the coconut palms contribute to the fight against marine erosion.
For illustrating this section, we can produce on request at least one large size HD poster (up to 180x100 cm in size). This poster should be adapted to each country, on a case-by-case basis, in order to prominently feature local specificities.
Research
on drought tolerance has shown variability for revival capacity, water use
efficiency, dry matter production and yield of coconut cultivars. Results
obtained in India indicated that hybrids using Talls as mother palms are
generally more tolerant to drought when compared with Dwarfs (Malayan types)
and with hybrids using Dwarfs as the mother palm.
Coconut palms dying from drougth in the Marquesas Islands, French Polynesia |
There is a significant potential market for cold-tolerant coconut varieties able to survive in countries with a temperate climate. The first cold-hardiness studies in Hainan Island (China) indicated the existence of genetic variability. The semi-lethal temperatures ranged from 7.3 to 12.4 ℃ according to the cultivar. Local Hainan Tall coconut varieties had the strongest growth vigour but lower yield when compared with some introduced cultivars.
Maoris coming from tropical Polynesian islands tried so many times to grow coconut palms in New Zealand but never succeeded due to the cold weather. Polynesians living in the Austral Islands (southern French Polynesia) also suffer greatly from scant coconut production. Because it gives any landscape a more ‘tropical’ look, many people attempt growing coconuts in non-tropical climates. Studies conducted in Florida shows that palms subjected to long periods of low temperature have soft, sunken, reddish areas on the trunk. These cold-damaged trunk areas are often invaded by secondary fungi and/or bacteria that cause trunk-rot and, several months later, the collapse of the entire crown. Fertilization may improve cold tolerance.