Leaf Spiral and Yield in Coconuts

Abstract

THIS communication refers to the recent article by Satyabalan, Ninan and Krishna Marar¹, who perhaps unconsciously give more publicity to my findings relating to foliar asymmetry in the coconut palm^2–4. The very first line of their statement, referring to the work of Petch⁵, is misleading. Petch did not deal with leaf-spirals of coconut in his paper and, in fact, there is no mention of leaf or foliar-spiral, or the arrangement of leaves along five spirals in a clockwise or anti-clockwise direction as reported. Presumably Petch's article was not available to the above authors. Petch explained the structure of the fibres in the coconut stem. Neglecting the outer rind, he found in a stem the vascular bundles sloping to the left in the outer 3.5 cm, followed by an abrupt reversal of direction for the next 3.5 cm. This was again followed by another reversal to the original left in the remaining inner core of the stem. In another stem, the condition was reversed; the same three regions were present, but in the outer the bundles sloped up to the right, in the intermediate to the left, and in the inner to the right again. These two types of palms were regarded by Petch as right- and left-handed coconut trees.