Abstract
Castor (Ricinus communis L.) is a plant that is commercially very important to the world. It is produced in about 30 countries lying in the tropical belt of the world. It is an important plant for production of industrial oil. Assessment of genetic diversity of a crop species is a prerequisite to its improvement; hence it is important to identify the genetic diversity of castor genetic resources for development of improved cultivars. The present study is focused on estimation of genetic distance between 56 Tunisian castor genotypes, based on 18 RAPD markers. Seeds of castor were obtained from the University of Carthage, National Institute of Research in Rural Engineering, Waters and Forests (INRGREF), Regional Station of Gabí¨s, Tunisia. The ricin genotypes were obtained from 12 regions of Tunisia. The efficacy of the RAPD technique in this study is further supported by the obtained PIC values of the primers used in the analysis. PCR amplification of DNA using 18 primers for RAPD analysis produced 145 DNA fragments that could be scored in all 56 genotypes of Tunisian castor. The number of amplified fragments varied from 3 (OPE-07) to 13 (SIGMA-D-01), and the amplicon size ranged from 100 to 1500 bp. Of the 145 amplified bands, 145 were polymorphic, with an average of 8.11 polymorphic bands per primer. The lowest values of polymorphic information content were recorded for RLZ 9 (0.618) and the the highest PIC values were detected for OPD-08 (0.846) with an average of 0.761. A dendrogram was constructed from a genetic distance matrix based on profiles of the 18 RAPD primers using the unweighted pair-group method with the arithmetic average (UPGMA). According to analysis, the collection of 56 Tunisian castor genotypes were clustered into five main clusters. Genetically the closest were four genotypes from cluster 1 (BT-1 - S-5 and K-1 - N-3). Knowledge of the genetic diversity of castor can be used in future breeding programs for increased oil production to meet the ever increasing demand of castor oil for industrial uses as well as for biodiesel production.
Highlights
Castor bean, Ricinus communis L. (2n = 20, X = 10), is a species of flowering plant in the spurge family, Euphorbiaceae
Genetic diversity in a germplasm is the fundamental requirement for crop improvement programs
polymerase chain reaction (PCR) amplification of DNA using 18 primers (Table 1) for random amplified polymorphic DNA (RAPD) analysis produced 145 DNA fragments that could be scored in all 56 genotypes of Tunisian castor (Figure 2)
Summary
Genetic diversity in castor bean was assessed by using both dominant and codominant molecular markers (random amplified polymorphic DNA, RAPD) (Reddy, Nadigatla and Mulpuri, 2015; Vivodík et al, 2015a), inter-simple sequence repeats (ISSR) (Wang et al, 2013; Vasconcelos et al, 2016), start codon targeted (SCoT) PCR amplification of DNA using 18 primers (Table 1) for RAPD analysis produced 145 DNA fragments that could be scored in all 56 genotypes of Tunisian castor (Figure 2).
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a call
