Genetic diversity analysis in cashew (Anacardium occidentale L.) germplasm using RAPD marker

Genetic distance in germplasm using RAPD

Abstract

Anacardium occidentale L., commonly known as cashew nut, belongs to the family Anacardiaceae.  It is regarded as a high valued fruit nut crop world-wide. Potential of this economically important nut  is under-utilized in Bangladesh in spite of having all favorable agro-climatic conditions. The objective of the present investigation was to characterize six cashew accessions using Random Amplified Polymorphic DNA (RAPD) markers. Four random primers viz. OPE-02, OPE-18, OPK-03 and OPB-15 were used to amplify DNA segments. A total of 33 reproducible bands were obtained, out of which 11 were monomorphic and 22 were polymorphic. On average 74.12% polymorphism was observed. . Primers OPB-15 and OPK-03 yielded 100% polymorphism and OPE 02 and OPE 18 produced 33.33% and 63.16 % polymorphism, respectively. Cluster analysis revealed two main distinct groups, first group included GP-1 and the second consisted of five genotypes viz. GP-2, GP-3, GP-4, GP-5and GP-6 The major cluster- II was further subdivided into two minor clusters i.e. minor cluster- III and IV. Minor cluster- III contained only one genotype GP-4. Minor cluster- IV consists of four rest genotypes. The genetic distance between the groups was found low and varied from 0.002 to 0.0308. Maximum genetic distance was observed between GP-1 and GP-2cashew germplasm and minimum between GP-5 and GP-6. The low genetic distance which is unusual for this out crossing long-lived tree species, indicates the probability of having common ancestry among the germplasm or may be due to the use of a narrow range of populations for the investigation.

J Bangladesh Agril Univ 17(4): 461–465, 2019