Assessment of <i>Stevia rebaudiana</i> Bertoni Genotypes via Morpho-Agronomic Traits under Two Light Conditions

Abstract

<i> Stevia rebaudiana </i> Bertoni, a non caloric natural sweetner is currently the available substitute to sugar. It is a genus of about 150 species of herbs and shrubs, a compositae and native to Paraguay. However, stevia is a short day plant with almost a constant day length < 12 hours in Malaysia stevia generated to flower early. Therefore, the aim of the study was to investigate the effect of different day length on <i> Stevia rebaudiana </i> genotypes in Malaysia. The experiment was undertaken during December 2016 to April 2017 in the Faculty of Design and Architecture, Universiti Putra Malaysia, Serdang, Selangor, Malaysia. Eight stevia genotypes namely (CHV1, Morita2, MS012, MS012 (4x), SA18, TPU, and hybrids IIUM-F1 and UiTM-H2) were evaluated for the agronomic traits under two conditions : sun light (<12 hours) and simulated light (>14 hours) using a factorial experiment. The agronomic performance of <i> Stevia rebaudiana </i> was significantly in long day length (>14 hours) environment comparing with short day length (<12 hours) environment. Stevia plants under sun light start to flower after seven weeks, from the other hand stevia plants under simulated light did not flower. All stevia genotypes showed a high performance under long day length (>14 hours) environments.