Morus alba L. (Mulberry) is an economic and medicinal tree, originated from the Himalaya region and gradually spread all over the world. Most of the recently developed mulberry varieties have similar narrow genetic base and limited capacity against environmental stress and pathogens. To enhance the species resistance, we need to increase genetic diversity of its varieties using higher genotypes differentiation in breeding programs. We investigated genetic diversity and structure of some mulberry Iranian populations to register different genotypes, which could be implemented in further genetic breeding programs. For this purpose, the nuclear genome of ten populations (4–7 individuals per each population) were extracted using the CTAB modified method and amplified using 30 ISSR primers. Genetic diversity parameters, polymorphism indexes and population structure were detected using GenAlex v. 6.4, GenoDive v. 2.0, PopGene v. 1.32 and Structure. We detected that the number of different alleles and polymorphic bands together with genetic diversity parameters varied among the populations. The results of AMOVA demonstrated the significant genetic interpopulation variations. Our research outputs were consistent with the high G_ST and H_T amounts and low rate of N_m and H_s, which indicating high genetic differentiation of the populations. These results suggested that genetic drift created high genetic differentiation among some populations. We determined the optimal value of K (6) by structure analysis and K-means clustering. This was supported by six detected genotypes among mulberry populations based on the UPGMA tree of Nei’s genetic distance, MDS plot, structure analysis and neighbor-net diagram. These genotypes have high genetic diversity, and they should be considered in prospective breeding programs to develop the mulberry varieties with improved yield and quality, and enhanced tolerance toward adverse environmental stress and diseases.

桑树L.（桑树）是一棵经济和药用树，起源于喜马拉雅山地区，并逐渐遍布世界各地。大多数最近开发的桑树品种具有相似的狭窄遗传基础，并且抵抗环境胁迫和病原体的能力有限。为了增强物种抗性，我们需要在育种计划中使用更高的基因型分化来增加其品种的遗传多样性。我们调查了一些桑树伊朗种群的遗传多样性和结构，以注册不同的基因型，这可以在进一步的基因育种计划中实施。为此，使用CTAB改良方法提取了10个种群（每个种群4–7个个体）的核基因组，并使用30种ISSR引物进行了扩增。遗传多样性参数 使用GenAlex v.6.4，GenoDive v.2.0，PopGene v.1.32和Structure检测多态性指标和种群结构。我们检测到不同等位基因和多态性条带的数量以及遗传多样性参数在人群中有所不同。AMOVA的结果证明了显着的遗传种群间差异。我们的研究结果与高G _ST和H _T的数量以及N _m和H _s的比率较低，这表明该群体的遗传分化较高。这些结果表明，遗传漂移在某些种群之间产生了高度的遗传分化。我们通过结构分析和K确定了K（6）的最优值-表示聚类。基于Nei的UPGMA树的遗传距离，MDS图，结构分析和邻居网络图，在桑树种群中检测到了六种基因型，这证明了这一点。这些基因型具有很高的遗传多样性，应该在前瞻性育种计划中考虑它们，以开发出具有更高产量和质量并增强了对不利环境压力和疾病的耐受性的桑树品种。