ECOPALM. A model to understand the complex phenology of mature oil palm
In mature palm plantation, the number of harvested bunches is the main component of yield. In Ivory Coast it varies from 600 to 1600 ha-1 year' with large seasonal variations from 2 to up to 300 bunches ha' month-' for L2T x D10D material. Phenology of adult oil palm is complex. The apical meristem initiates new leaves (20 to 30 per year) with a constant plastochron. Leaf lifespan from initiation to senescence is more than 4 years. The first unopened leaf emerging from the crown is spear-leaf (rank 0). Approximately 60 developing leaves are hidden in the crown (ranks -1 to -60) and 40 autotrophic expanded leaves are visible (Corley and Tinker 2003). Each leaf bears a male or female inflorescence which is first visible at flowering (rank 18 to 20). Bunch is harvested 5 to 6 months after flowering. By dissection of the crown and electronic microscopy, the inflorescence primordia can be seen at rank -40 but the sex cannot be identified before rank 4 (Adam & al. 2005). The determinism of gender is highly dependent of environment and physiological stress but is not explained. The time and duration of sex differentiation are not known with certainty: it can be assumed at spikelet initiation (rank -5 to -10) or at bract initiation (rank -20 to -30) or at any time between rank -10 to -30 (Jones 1997). Abortions occur between ranks 8 to 12, but, because some leaves have no inflorescence, an ealier sensitive phase may occur. Because of weak evidence and of the difficulty of experiments, crop modeling is a way to test hypotheses. For example, in a model simulating seasonal trends at tree level, Jones (1997) introduced a feedback loop of bunch load to induce physiological stress in earlier stages responsible of abortion or sex differentiation.
Main Authors: | , , , , |
---|---|
Format: | conference_item biblioteca |
Language: | eng |
Published: |
Agropolis international
|
Subjects: | U10 - Informatique, mathématiques et statistiques, F62 - Physiologie végétale - Croissance et développement, Elaeis guineensis, modèle mathématique, http://aims.fao.org/aos/agrovoc/c_2509, http://aims.fao.org/aos/agrovoc/c_24199, |
Online Access: | http://agritrop.cirad.fr/557370/ http://agritrop.cirad.fr/557370/1/ID557370.pdf |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | In mature palm plantation, the number of harvested bunches is the main component of yield. In Ivory Coast it varies from 600 to 1600 ha-1 year' with large seasonal variations from 2 to up to 300 bunches ha' month-' for L2T x D10D material. Phenology of adult oil palm is complex. The apical meristem initiates new leaves (20 to 30 per year) with a constant plastochron. Leaf lifespan from initiation to senescence is more than 4 years. The first unopened leaf emerging from the crown is spear-leaf (rank 0). Approximately 60 developing leaves are hidden in the crown (ranks -1 to -60) and 40 autotrophic expanded leaves are visible (Corley and Tinker 2003). Each leaf bears a male or female inflorescence which is first visible at flowering (rank 18 to 20). Bunch is harvested 5 to 6 months after flowering. By dissection of the crown and electronic microscopy, the inflorescence primordia can be seen at rank -40 but the sex cannot be identified before rank 4 (Adam & al. 2005). The determinism of gender is highly dependent of environment and physiological stress but is not explained. The time and duration of sex differentiation are not known with certainty: it can be assumed at spikelet initiation (rank -5 to -10) or at bract initiation (rank -20 to -30) or at any time between rank -10 to -30 (Jones 1997). Abortions occur between ranks 8 to 12, but, because some leaves have no inflorescence, an ealier sensitive phase may occur. Because of weak evidence and of the difficulty of experiments, crop modeling is a way to test hypotheses. For example, in a model simulating seasonal trends at tree level, Jones (1997) introduced a feedback loop of bunch load to induce physiological stress in earlier stages responsible of abortion or sex differentiation. |
---|