Stevia rebaudianaBertoni originally from Paraguay belongs in Asteraceae family. It is an alternative source of non-caloric sweetener due to the sweet steviol glycosides contained in the leaves. As an introduced species in Malaysia, it is important to elucidate the genetic variabilities and relatedness among stevia accessions in order to broaden the genetic basis for future stevia breeding. This study described morphological and chemical variations and investigates genetic relationships among stevia accessions derived from across Malaysia and Paraguay using inter simple sequence repeats (ISSR) markers. HPLC (high-performance liquid chromatography) analysis also revealed high variability with stevioside content between 4.54 % (Taman Pertanian) to 20.36 % (Bangi) and rebaudioside A content varied between 0.3 % (Nilai) to 2.04 % (MNQ). From 32 ISSR markers, a total of 332 bands were scored, of which 264 (78 %) were polymorphic. The dendrogram from UPGMA (Unweighted Pair Group Method with Arithmetic Mean) cluster analysis separated 17 stevia accessions into 3 main groups. Rawang and Nilai were found to be closely related. The wide genetic variabilities among stevia accessions are a promising indicator towards the development of new stevia varieties. This valuable information will be able to assist parental selection in future stevia breeding programmes.

AbstractMomordica cochinchinensis, or Gac fruit belongs to Cucurbitaceae family. Although this species is considered to be native in Southeast Asia especially in Vietnam, Thailand and Laos, it is still contemplated as a rare and new fruit species in Malaysia. Availability of this species is very limited in Malaysia hence, the raw material for researches is also in short supply. Currently, Gac fruit is utilized as traditional food, health supplements, food colouring and juices. Gac fruit was discovered to have high value pharmaceutically and economically as it had been recognized as a rich source of bioactive compounds. On that account, this study aimed to generate preliminary data on the morphological characterisation and phytochemical composition which focused on β-carotene and lycopene content of Gac fruit aril. This data could be useful for further researches particularly on breeding improvement of Gac fruit. The morphological characterisation was mainly based on both vegetative and reproductive parts of the plant. Both β-carotene and lycopene content of aril was analysed and estimated using UV-Vis Spectroscopy technique. The aril was extracted using mixed solvent of n-hexane 95%, ethanol 99.9% and acetone 99% with ratio of 2:1:1 v/v/v. Furthermore, morphological data of root, stem, leaf, flower, fruit and seeds were also successfully recorded. Besides that, the β-carotene and lycopene content obtained were 0.117 ± 0.011 mg/g FW and 0.021 ± 0.002 mg/g FW, respectively. Discrepancy in the results might be due to numerous factors like collection sites, level of maturity at harvest, storage and processing conditions, analysis techniques and type of solvent extractors used that might have affected the quality and contents of the carotenoid. Several suggestions for extension of this study had been propounded so that the benefits of this species could be exploited in the best possible ways.

Hybridization is an important method to widen variations and to develop novel varieties in plants. The increasing interest in Stevia rebaudiana over the last decade soared by its potential as an alternative source of sugar. In this study, improvement in stevia has been conducted through hybridization using Trigona for the development of stevia hybrids. Trigona, which consists of small to medium-sized bees, is usually found in tropical and subtropical parts of the world. They are common visitors to flowering plants and pose an important function as crop pollinators. A field experiment was conducted using 17 stevia accessions (From Malaysia and Paraguay), and F1 hybrids were morphologically and chemically evaluated. Among the F1 individuals, a wide range of variability with regards to qualitative and quantitative morphological parameters was observed. A selection of F1 hybrids namely MS007HYB1, MS007HYB2, LangatHYB, EireteIIHYB, NilaiHYB1, NilaiHYB2, and NilaiHYB3 was made based on their promising features. Improvements were observed in total stevioside content for MS007HYB1 (45%) and MS007HYB2 (30%), rebaudioside content for MS007HYB2 (4.2%), NilaiHYB2 (3.8%), NilaiHYB3 (3.6%) and LangatHYB (14.4%), and delay in flowering for MS007HYB1 (46 days), MS007HYB2 (46 days), LangatHYB (51 days), EireteHYB (47 days), NilaiHYB1 (49 days), NIlaiHYB2 (46 days) and NilaiHYB3 (46 days) when compared to their respective mother plants.