Effect of Seed Cluster and Gibberelic Acid (GA3) on the Gender Development of Salacca edulis REINW. (Snake fruit) Grown on BRIS soil

Abstract

Salacca edulis REINW. (Snake fruit) is a monocotyledon plant belonging to the palmae family. Climate requirement for this plant is equatorial. A series of experiments on the growth and development of S. edulis were conducted in the greenhouse of University Malaysia Terengganu (UMT) and in the field on undeveloped agricultural land (BRIS soil) in Tumpat, Kelantan. A nursery study was undertaken for six months followed by a field study for 24 months. The aim of both studies was to determine the possible effect of GA₃ and seed clusters in the fruit of S. edulis on gender determination of the plant during early growth. Gender determination is a major problem in S. edulis orchard industry where farmers often fail to identify male and female plants at the earlier stage because of their dioecious nature and morphological similarity, except the flower which appears during the reproductive stage. Based on the results of this study, there were strong relationships between the number of seeds per fruit and plant gender. For female plants; single seed produced 20%, two seeds produced 33% and three seeds produced 42%. Results showed a positive correlation between number of seeds and percentage of female plants they produced. It was concluded that fruit containing three seeds gave a better combination of male and female S. edulis planting materials and it was good for commercial planting. Application of GA₃ treatment did not give a strong effect for gender determination. However, the highest rate of GA₃ (100 ppm) promoted early flowering. The male flowers contain auxin: Indole-acetic-acid (IAA) and Abscisic acid (ABA) but have no gibberellins (GA₃). Meanwhile, the female flowers contain IAA and GA but have no ABA. This finding also proves that, with proper management such as the use of right organic fertilizer and irrigation system, S. edulis can be planted on BRIS soil which has poor physical and chemical properties due to its lack of clay.

Keywords: Seed cluster, BRIS soil, gibberelic acid, Salacca edulis, dioecious