Intersimple Repeat (ISSR) consists of semi-arbitrary markers amplified by the polymerase chain reaction (PCR) using primers complementary to the target microsatellite. ISSR does not require genomic sequence information. In addition, it produces polymorphic, highly polymorphic patterns and produces dominant markers. In addition, as a genotyping technique, ISSR-PCR is fast, inexpensive, based on region variation between microsatellites, and is technically simpler than many other marker systems. This method provides reproducible results and produces abundant polymorphisms in many systems (Abdel-Mawgood 2012; Wolfe et al., 1998).
Genetic variation is an important tool for assessing the biological potential of an organism. Populations with high genetic variation can cope well with environmental changes such as water fluctuations, temperature fluctuations, and epidemics (Alam et al., 2010). On the other hand, reducing genetic diversity may increase susceptibility to environmental changes and ultimately lead to species extinction (Evans et al., 2010). This reduction in genetic diversity can affect growth and reproduction (Dixon et al., 2008). Therefore, maintaining a high level of genetic diversity is very important for species conservation (Barroso et al., 2008). Individuals need to be able to withstand changes in the environment and grow well. Therefore, genetic monitoring is ideal for use in reproductive programs aimed at genetic conservation (storage). Molecular markers are a viable and useful tool for studying and monitoring is ideal for use in a reproduction program with the aim of genetic conservation (stocking). Molecular markers are a viable and useful tool for studying and monitoring the genetic status of both natural populations (Alam and Islam2005). In this study, the similarity between specimens 2 and 3 is 0.11, which means that the genetic distance between some specimens is high, and the genetic distance between these two specimens is 0.89. Similarly, the genetic distance between samples 6 and 7 is 0.67. This suggests that rivers may be inhabited by multiple species of shellfish and need to be categorized. However, some individuals are very similar and can be classified as one species as follows: B. Items 3 and 7 and items 4 and 5 on different pages.
The first study of Egyptian freshwater mussels involved two populations collected from the Nile in Giza Governorate, Egypt (Mandahl-Barth1988). He classified them as a species belonging to the Unionidae family. However, others separated them as two different species (Ibrahim et al., 1999). In addition, a randomly amplified DNA polymerase polymorphism chain reaction marker (RAPD-PCR) was used to determine the genetic distance (D) between the two Unionidae species (Sleem and Ali2009). He concluded that the high genetic distance between the two specimens (0.64) suggests that they are two different species (Sleem and Ali, 2009).
very similar group of individuals. In addition, copies 2 and 6 form the third branch. In general, the genetic diversity of freshwater mussels seems to be relatively high. This may be because they are made up of multiple species. For example, the RAPD technique was used on populations collected from three water bodies in India, and the genetic diversity value reached 0.99, indicating that there is high genetic diversity between the population and individuals of the same species. (Alam et al., 2010). Several other studies support the discovery of the presence of high genetic diversity in freshwater mussels. Using 19 microsatellite markers and 64 specimens, one study considers the freshwater mussels (Unionidae) in the Yangtze River basin of China to be one of the most diverse communities on earth (Liu). et al., 2017). Another study concludes that global estimates of freshwater mussel diversity are 840 species in 161 genera6. Regional diversity is Nearctica: 302 spp., Neotropica: 172, Afrotropica: 85, Palearctica: 45, Indotropica: 219 and Australasia: 33, and that largest family is the Unionidae, with 674 species (Graf and Cummings, 2007).
Genetic diversity is important for species to survive changes in the environment. The presence of high genetic diversity among aquatic populations could significantly contribute to increasing the potential for evolution to address habitat changes, the effects of pathogen infections, and other selectivity. There are (Freeland et al., 2011; Liu and Yao 2013; MacDonald et al., 2011). The results presented here showed that the samples collected at Avohomos in Behera province show moderate genetic diversity. They have slightly higher levels of genetic variation and therefore have slightly greater ability to potentially adapt to their environment. Meanwhile, other studies suggest that freshwater mussels are considered one of the most endangered animal groups in the world (Aldridge et al., 2007; Vaughn 2010). Similarly, it has been suggested that freshwater mussels are a vulnerable group and may face global decline (Gallardo2018). Later studies predicted a major distribution contraction of the endemic freshwater fauna and fragmentation of the remaining suitable habitat. Their research has led to future expeditions to monitor the conservation status of freshwater biodiversity. A summary of the national conservation status of mussels in East and Southeast Asian countries (Zieritz et al., 2018). The major threats to the demographics of these countries are pollution, deforestation, interaction with alien species, changes in land use, dam construction and mining, climate change, sediment accumulation, overfishing and alien species predation. It was indicated that the major threats to the population diversity in these countries were pollution, deforestation, interaction with nonnative species, land-use change, dam construction and mining, climate change, sediment accumulation, overharvesting, nonnative predators, hydrological alterations, and urbanization (Zieritz et al., 2018).