International Journal of Agriculture, Environment & Biotechnology

Citation: IJAEB: 7 Special Issue : 459-465 July 2014

©2014 New Delhi Publishers. All rights reserved

7

Molecular Biology

Molecular study of Pigeonpea [ Cajanuscajan (L.) Mill sp.]

Genotypes for Fusarium wilt using RAPD markers

Vijay Prajapati*, Nishit Soni and N. Sasidharan

Department of Genetics and Plant Breeding, Anand Agricultural University, Anand – 388 110 (Gujarat), India.

*Corresponding author: Vijay Prajapati; vijay_microlife105@yahoo.com

Abstract

The molecular study of seventeen genotypes of pigeonpea using 20 random amplified polymorphic DNA (RAPD) markers has been reported.

A total of 179 loci were scored corresponding to an average of 8.95 loci per primer with 123 bands showing polymorphism (65.42%).Very

low level of polymorphism in cultivated pigeonpeagermplasm had been earlier reported which was corroborated by many pigeonpea workers

indicating the normal genetic base existing in this crop (Odeny et al . 2007). The average number of polymorphic loci obtained per primer

(Assay Efficiency Index) was found to be 6.15. Jaccard’s similarity coefficient ranged from 0.52 to 0.77 and the marker index value for pooled

RAPD was found to be 11.65. A dendrogram constructed based on the UPGMA clustering method revealed two major clusters. Cluster-I

comprised of 5 cultivars whichwas further differentiated into two sub-clusters. The cluster-II included remaining twelve cultivars. Genotypes

that are susceptible to fusarium wilt of pigeonpea viz ., GT-1, GT-100, GT-101, GT-102 and BANAS were closely related and they formed one

cluster. It also revealed that genotypes viz ., AGT-2 and AVPP-1 were closely related and formed one cluster whereas viz ., T-15-15, LRG-

41, C-11, BDN-2 and ICPL-87 were closely related and formed another cluster. The dendogram showed that genotypes that are resistant to

fusarium wilt of pigeonpea viz ., BSMR-853, WRGE-119, ICPL-87119, ICPL-84060 and ICP-8863 were related genotypes and they formed

another cluster. The study reiterated that RAPD can be efficiently used for discriminating resistant and susceptible pigeonpea genotypes.

Highlights

A total of 179 loci were scored corresponding to an average of 8.95 loci per primer.

Jaccard’s similarity coefficient ranged from 0.52 to 0.77 and the marker index value for pooled RAPD was found to be 11.65.

Very low level of polymorphism (65.42%) in cultivated pigeonpea genotypes was reported.

RAPD can be efficiently used for discriminating resistant and susceptible pigeonpea genotypes

Keywords: RAPD; Pigeon pea; Fusarium wilt; Dendrogram; Genotypes.

Pigeonpea or Red Gram [ Cajanuscajan (L.) Millsp.]

pigeonpea is attacked by more than 100 pathogens (Nene

(2n = 22) is the second most important pulse crop and

et al., 1989). These include fungi, bacteria, viruses,

plays an important role in subsistence agriculture. The

nematodes and phytoplasma. In Gujarat, the fusarium wilt

chromosome number of all Cajanus species is n=11, with

is one of the major diseases of concern followed by

a genome size of 808 Mbp (Greilhuber and Obermayer,

Phytophthora blight and sterility mosaic, affecting the

1998). India is considered as the primary center of

productivity of this crop per unit area. Fusarium wilt

origin for pigeonpea while Africa as the secondary

of pigeonpea is a soil borne disease caused by fungus

center of origin (Van der Maesen, 1980). Its grains are

Fusariumudum . Therefore, to minimize yield losses due

highly nutritious and rich in protein content (21-23%),

to fusarium wilt, it is necessary to tackle these problems

carbohydrates, fiber and minerals. During its life span,

at molecular level by developing cultivars which resist/