Molecular characterization of cassava chips line CMR-100 and its progenies using SSR markers

Abstract

The study entitled “Molecular characterization of cassava chips line CMR-100 and its progenies using SSR markers” was carried out in Division of Crop Improvement, ICAR-CTCRI, Thiruvananthapuram during 2015-2016 with an aim to identify the parents of CMR-100 and to assess the genetic variations among the OP progenies of CMR-100 with selected cassava cultivars. Cassava chips line CMR-100 was identified in ICAR-CTCRI and is ideal for chips making, because it has uniform cylindrical tuber shape. The parents of this cassava line are unknown since it is a product of open pollination. The marker analysis for the parental identification of this chips line reveals 97 percent similarity with C-129 and 90 percent with C-15 in cluster based dendrogram. This result suggesting that these two lines may be the parents of CMR-100. Similar results were obtained in both 2D and 3D plots. CMR-100 shows 0.93 similarity index value with C-129 which is the highest coefficient value obtained whereas C-15 shows 0.84. The banding patterns of these three lines were compared using 19 SSR products, which reveals that atleast one parental allele is present in the hybrid. The PIC value ranges from 0.30 to 0.75 and heterozygosity from 0.36 to 0.78 and 14 SSR markers were found to be highly polymorphic and informative.The genetic variability of OP progenies using molecular markers reveals 67 percent similarity of progenies suggesting that female characters are expressed more in the progenies than male characters. All the OP progenies of CMR-100 along with CMR-100 and its expected parents were grouped in a single cluster at similarity coefficient value 0.63. The progeny CMR-100/60 shows 97 per cent similarity with CMR-100 suggesting that it is a selfed progeny of CMR-100. The PIC value ranges from 0.21 to 0.78 and heterozygosity from 0.24 to 0.81 and three SSR markers were highly polymorphic and informative.