~ 4961 ~ International Journal of Chemical Studies 2019; 7(3): 4961-4967 P-ISSN: 2349–8528 E-ISSN: 2321–4902 IJCS 2019; 7(3): 4961-4967 © 2019 IJCS Received: 19-03-2019 Accepted: 21-04-2019 G Koteswara Rao Department of Vegetable Science, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India NB Patel Department of Vegetable Science, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India AI Patel Department of Vegetable Science, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India KD Desai Department of Vegetable Science, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India TR Ahlawat Department of fruit science, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India Chintan Kapadia Department of plant molecular biology and biotechnology, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India Correspondence G Koteswara Rao Department of Vegetable Science, ASPEE College of Horticulture and Forestry, Navsari Agricultural University, Navsari, Gujarat, India Characterization of greater yam ( Dioscorea alata L.) genotypes by using morphological markers G Koteswara Rao, NB Patel, AI Patel, KD Desai, TR Ahlawat and Chintan Kapadia Abstract The present investigation was undertaken to characterize the morphological traits among 27 genotypes of greater yam (Dioscorea alata L.) by using morphological markers in a randomized block design with three replications during kharif 2017-18 and 2018-19 at AICRP on tuber crops project, RHRS farm, ACHF, NAU, Navsari. The morphological characterization for 19 characters revealed high variation among the genotypes in terms of shape of leaf, position of leaf, distance between lobes, colour of wing, stem and leaf, pigmentation of petiole on leaf base, formation of aerial tuber, skin and flesh colour of underground tuber, shape of tuber, presence of hairiness on tuber and spines on stem. Keywords: Dioscorea alata, greater yam, genotypes, characterization, and morphological markers Introduction Greater yam (Dioscorea alata L. 2n=4x=40), is polyploid known as purple yam, greater asiatic yam, ten months yam, water yam and winged yam belongs to the family Dioscoreaceae, originated in South East Asia. More than 600 Dioscorea species present in world and Africa, America, Asia and Polynesia are its main habitat, where some of the yam species are economically significant tuber crops (Coursey, 1967) [5] . The species of Dioscorea (yam) are regarded as a staple food crop for millions of people in the tropical and subtropical regions of the world. It is regarded as an important food crop next to cereals and grains due to high yield storage of carbohydrates. Greater yam is one of the largely cultivated yam species with the largest world distribution and one of the oldest cultivated yam species (Lebot, 2009) [7] . In India, greater yam is cultivated in the states of Andhra Pradesh, Kerala, West Bengal, Bihar, Odisha, North Eastern states, Uttar Pradesh, Tamil Nadu, Gujarat and Maharashtra (Chadha, 2002) [4] . In Gujarat, it is cultivated in Valsad, Navsari, Dangs, Panchmahals, Surat and Tapi districts. In plant breeding, markers that are related to variation in shape, size, colour and surface of various plant parts are called morphological markers. Such markers refer to available gene loci that have obvious impact on morphology of plant. Genes that affect form, coloration, male sterility or resistance among others have been analyzed in many plant species. The objectives of this study were to determine the relationships between the genotypes, and to identify duplicates and groupings of genotypes in the germplasm of yams collected from different districts of Gujarat and CTCRI, Kerala. The exploitation of the genetic diversity so determined serves to facilitate the development of better varieties through combination and marker assisted breeding program. Materials and Methods The plant materials used for morphological studies comprises of twenty seven genotypes of D. alata conserved in the AICRP on tuber crops project at RHRS farm, NAU, Navsari, Gujarat. The details of materials used for the study is given in Table 1.