Varietal evaluation, ploidy manipulation and biotechnological studies in papaya

Abstract

Investigation on “Varietal evaluation ploidy manipulation and biotechnological studies in papaya’’ was carried out at Indian Institute of Horticultural Research, Bangalore from June, 2002 to July, 2003. Varietal evaluation was carried out using eighteen C. papaya genotypes and two wild species viz., C. cauliflora and C. goudotiana. In the evaluation process significant differences were observed among the genotypes for the vegetative characters such as plant height, stem girth, number of leaves and plant spread and fruit characters such as fruit weight, fruit volume, fruit length, fruit width, pulp thickness, cavity index, total soluble solids, pulp colour and hundred seed weight. Cluster Analysis and Principal Component Analysis were carried out for the genotypes. Cluster analysis constructed a dendrogram, which grouped genotypes into three clusters. Cluster I comprised of Nigeria, PAU Sel, Coorg Honey Dew, Red Indian, Thailand, Madhubala, Pusa Nanha, Shillong and CO-5. Cluster II comprised of Pink Flesh Sweet, Co2, Dwarf, Pant-2, Waimanalo, Surya and Mauritius. Cluster III comprised of Sunrise Solo, Sunset Solo, Carica cauliflora and Carica goudotiana. The varieties Sunrise Solo and Sunset Solo got grouped with the wild species, mainly because of the fruit size. Genetic diversity and hybridity testing was also carried out using Randomly Amplified Polymorphic DNA markers. In the present investigation nineteen varieties and two species were selected