Microsatellite-Based DNA Fingerprinting and Genetic Analysis of Some Selected Aus Rice (<em>Oryza sativa L.</em>) Genotypes

Special Article - Abiotic Stress

Ann Agric Crop Sci. 2020; 5(3): 1066.

Microsatellite-Based DNA Fingerprinting and Genetic Analysis of Some Selected Aus Rice (Oryza sativa L.) Genotypes

Hossain MA1, Islam MM2, Emon RM3, Rana MS3*, Hossain MA4*, Uddin MI2, Malek MA3, Khan NA2 and Nuruzzaman M4

1Department of Biotechnology, Bangladesh Agricultural University, Bangladesh

2Biotechnology Division, Bangladesh Institute of Nuclear Agriculture, Bangladesh

3Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture, Bangladesh

4Department of Genetics and Plant Breeding, Bangladesh Agricultural University, Bangladesh

*Corresponding author: Md. Shohel Rana, Plant Breeding Division, Bangladesh Institute of Nuclear Agriculture, Mymensingh-2202, Bangladesh

Mohammad Anwar Hossain, Department of Genetics and Plant Breeding, Bangladesh Agricultural University, Mymensingh-2202, Bangladesh

Received: November 30, 2020; Accepted: December 22, 2020; Published: December 29, 2020

Abstract

The allelic diversity and molecular characterization of 30 Aus genotypes were done through DNA fingerprinting using microsatellite (SSR) markers. All the 30 amplified products have polymorphic bands giving 176 alleles. The number of alleles per locus ranged from 4 (RM536) to 20 (RM209), with an average of 9.4889 alleles across 45 loci. A total of 156 rare alleles were detected on 45 loci, whereas 31 null alleles were detected on 30 loci. The Polymorphism Information Contents (PIC) value lied between 0.5511 (RM134) to 0.9199 (RM209). Most robust marker was found to be RM209 since it provided the highest PIC value (0.9199), followed by RM144 (0.912) and RM153 (0.9070). Pair-wise genetic dissimilarity co-efficient showed that the lowest genetic dissimilarity value (0.11) was found between BRRI dhan42 and BRRI dhan43 and the highest genetic dissimilarity value (1.00) was found among all local landraces. The Unweighted Pair Group Method with Arithmetic mean (UPGMA) dendrogram revealed 6 clusters. Cluster I contain seven local landraces: Tusha, Tapa Sail, Udobali, ZamirSaita, Soda, Soil Bogi and Tarabali. Cluster II contain BR1, BR2, BR3, BR6, BR7, BR8, BR9. Cluster III has BR12, BR15, BR16, BR20, BR21. Tepakain is in cluster IV. Cluster V contains BRRI dhan27, BRRI dhan42, BRRI dhan43, BRRI dhan48, BR24, BR26 and cluster VI with SadaBogi, Usha, Sada Aus and Saita. Most Aus landraces is recognized to have broad genetic base. Thus, these landraces can be used for future breeding program or new genes can be incorporated into the landraces to broaden the genetic base.

Keywords: DNA fingerprinting; Genetic analysis; Landraces; Polymorphism Information Contents (PIC); Aus rice

Introduction

Rice is one of the most important cereal crops which grow in all growing seasons of Bangladesh. It grows in all the three crop growing seasons of the year and occupies about 77% (11.42Mha) of the total cropped area of about 14.94 million hectares [1]. According to the United Nations (UN) estimates, the current world population 6.1 billion is expected to reach 8.0 billion by 2025. Bangladesh is already under pressure both from huge and increasing demands for food, and from problems of agricultural land and water resources depletion. Bangladesh needs to increase the rice yield in order to meet the growing demand for food emanating from population growth.

Large variations in morphological, biochemical traits and DNA polymorphism exist in rice in Asia, its center of origin, with sub-centers of diversity in China and Indian subcontinent where both indica and japonica subspecies have been found to grow with abundant variation [2,3]. There is wide genetic variability available within existing varieties of rice and wild relatives providing wide scope for future crop improvement [4,5]. As the number of rice cultivars increases, the ability to distinguish them on the basis of morphological and biochemical traits becomes more difficult mostly due to genotype-environment interaction. Any developed or derived cultivar requires clarity from its precursor for identity and protection. Both breeders and farmers tend to select among variations in their fields in order to maintain the purity of the varieties or screen for a new type. For the study of genetic diversity, the plant scientists have used generally morphological, physiological as well as molecular characterization of plant. Moreover, in most cases, plant genomes have large amount of repetitive DNA which are not expressed and do not contribute to the physiological or morphological appearance of plants. In the case of very closely related plant varieties, there are very few morphological differences, which as a matter of fact do not represent the true genetic differences at DNA level. So, there is always a need to study polymorphism at DNA level, which can be an indicative of genetic diversity [6]. It is thus apparent that the use of molecular genetic markers would provide one solution to the problem of providing unique DNA profiles for the protection of new rice cultivars. With the development of a wide range of molecular techniques, marker-assisted breeding is now used to enhance traditional breeding programs to improve crops [7]. These include Restriction Fragment Length Polymorphism (RFLP), simple sequence repeats (SSR), random amplification of polymorphic DNA (RAPD) and the Amplified Fragment Length Polymorphism (AFLP). PCR-based markers such as microsatellites are co-dominant, hyper variable, abundant and well distributed throughout the rice genome [8]. Microsatellites have shown great promise in genetic diversity, genome mapping, gene tagging and Marker-Assisted Selection (MAS) because they are technically simple, time saving, highly informative and require small amount of DNA. Abundance of microsatellite markers is now available through the published high-density linkage map [9,10] or public database.