International Journal of Horticulture, 2016, Vol.6, No.2, 1-10
1
Research Article Open Access
Assessment of Molecular Genetic Diversity and Identification of Elite Cashew
Hybrids
Sethi K.
1
, Lenka P.C.
1
, Tripathy Swapan K.
2,
, Priyadarshini Mohanty
3
1. Department of Fruit Science and Horticulture Technology, College of Agriculture, OUAT, Bhubaneswar, India
2. Department of Agricultural Biotechnology, College of Agriculture, OUAT, Bhubaneswar, India
3. Department of Plant Breeding and Genetics, College of Agriculture, OUAT, Bhubaneswar India
Corresponding email
International Journal of Horticulture 2016, Vol.6, No.2 doi
Received: 18 Dec., 2015
Accepted: 17 Feb., 2016
Published: 15 Mar., 2016
Copyright
© 2016 This is an open access article published under the terms of the Creative Commons Attribution License, which permits unrestricted use,
distribution, and reproduction in any medium, provided the original work is properly cited.
Preferred citation for this article
:
Sethi K., Lenka P.C., Tripathy S.K., and Priyadarshini M., 2016, Assessment of molecular genetic diversity and identification of elite cashew hybrids,
International Journal of Horticulture, 6(2): 1-18 (doi
Abstract
Genetic diversity among 20 cashew hybrids and their eight parents were assessed using 15 RAPD primers which resulted
1742 alleles with an average of 62.21alleles per genotype. RAPD profiles revealed 94 polymorphic bands out of total 107 scorable bands
resulting 87.85% polymorphism. On an average 7.66 bands were produced with a range of 4-15 amplicons per primer. The maximum
number (14) of polymorphic bands (210 to 3250bp) was produced by primer OU-34 with high polymorphic information content (PIC)
and resolving power (Rp) values. Cashew hybrids H 6 and D 19 maintained very high level of average genetic dissimilarity with rest of
the test genotypes. The above hybrids comprising the most divergent genetic group (Cluster-I) had shown significantly above average
productivity and these could enrich the cashew gene pool for further genetic improvement for nut quality and yield per se. Besides, the
genotype-specific bands identified in the present study are useful for identification of cashew genotypes.
Keywords
RAPD profiling; Agronomic traits; Genetic diversity; Varietal identification; Cashew hybrids
Introduction
Cashew is native to Brazil, but India is the largest producer and exporter of cashew owing to its highly valued
kernel and fruits. Its kernel is nutritionally equivalent to milk, egg and meat and it reduces level of cholesterol in
blood. Major producer of cashew are India, Tanzania, Mozambique and Kenya. It is widely adapted to varying
agro-climatic conditions and there exists a large variation in cashew genotypes. Cashew is a naturally cross
pollinated crop and therefore, it maintains high level of genetic variability amenable for commercial exploitation.
Genetic diversity can be studied using morphological, biochemical and molecular markers. However, molecular
markers offer special advantage as they cover appreciably large area of the genome (Smith and Smith, 1989) and
show detailed genetic differences in a faster way without any environmental influence (Souza et al., 2008).
Besides, these are highly heritable and exhibit wide polymorphism to discriminate cultivars, hybrids, mutants and
chimeras. Molecular data associated with phenotypic observations can increase the efficiency and quantum of
selection in limited time span (Melo et al., 2002). Therefore, many workers attempted to associate molecular data
with morphological information to analyze genetic diversity and detection of QTL for agro-economic traits of
commercial importance (Cavalcanti et al., 2012). Among the molecular marker techniques, RAPD is simple,
cheaper, rapid, and economical and requires very small amount of DNA with lower purity and eliminates the need
for blotting, sequence information and radio-active detection. Therefore, a set of high yielding cashew hybrids
along with their parents were subjected to molecular analysis for DNA profiling using RAPD primers. Besides,
the probable association of DNA profile based clustering pattern in relation to specific characteristic
agro-economic features have been investigated for genetic improvement in cashew nut.
Materials and Methods
Genomic DNA was isolated from 2 g tender young leaves of a set of 20 high yielding experimental cashew
hybrids comprising ten cross combinations (e.g., Cross A – RP-1X Kalyanpur Bold Nut, Cross B - RP-1 x VTH
-711/4, Cross C – RP-2 x Kankadi, Cross D – M-44/3 x VTH 711/4, Cross E – RP-1 x Kankadi, Cross F – RP-2 x
