Leaf Characteristics and Shape of Sago Palm (Metroxylon sagu Rottb.) for Developing a Method of Estimating Leaf Area

Abstract

We aimed to determine the orientation for developing the method to estimate leaf area of sago palm (Metroxylon sagu Rottb.) by extracting characteristics that might be related to estimating leaf area from characteristics of leaves. Plants of around two years after trunk formation at a sago palm farm in Sarawak, Malaysia were used for the investigation. In a plant with eleven living leaves, the length of the unfolded leaf blade ranged from 6.0 to 7.2 m; the length of a petiole ranged from 1.8 to 3.1 m. The number of leaflets on the left side of a leaf viewing adaxial leaf surface with the tip upward was larger than that on the right side by 1-5 leaflets in all leaves. The lowest leaflet of a leaf was on the left side in all leaves. The relative position of the lowest leaflet on the rachis was related to the way a leaf was folded in a plant. The length, width and area of the right and the left leaflets were compared on the basis of their position on a rachis. They had approximately the same dimensions. This fact implied that those characteristics were almost symmetric with respect to the rachis; therefore, the position of a leaflet on a rachis was considered to be an important characteristic for analyzing leaf area. We drew a leaf diagram based on the measured data and examined a method of estimating leaf area using the leaf outline, but the method was not suitable. We decided to examine a method to integrate the leaflet areas for accurate estimation of the leaf area.

Keywords

• Leaf area
• Leaf shape
• Leaflet
• Leaflet area
• Metroxylon sagu Rottb
• Sago palm