Eco-Physiological Studies on Citrullus colocynthis (L.) Schard and Cucumis prophetarum (Jusl. ap.) L. in Saudi Arabia. 1. Seed Germination PDF

Keywords

seeds, Saudi Arabia, Citrullus colocynthis, Cucumis prophetarum

Abstract

Water absorbed as percentage of original weight of seeds of Citrullus colocynthis and Cucumis prophetarum increased markedly during the first experimental four hours and reached constancy thereafter. Percentage water absorbed after 24 hr was 20 and 34 for freshly harvested seeds and seeds stored for one year of Citrullus compared to 92% for Cucumis seeds. Seed germination percentage of Cucumis at different temperatures increased rapidly during the first four days, the highest being 68% on the fifth day at 25°C. Freshly harvested seeds of Citrullus as well as seeds stored for one year are dormant, while seeds stored for eight years reached their highest germination (50%) at 25°C on the 10th day. However chiling for one month at 4°C or treatment with 500 ppm kinetin (K) stimulated germination of seeds stored for one year where germination was 37 and 23% respectively. Neither gibberellin A3 (GA) nor mixture of GA and K stimulated the germination of these seeds. Sulphuric acid failed stimulate germination of freshly harvested seeds.