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The phenotypic diversity of the Iranian orchids has sharply decreased during the last 15 years and is currently threatened with local extinction and global climatic changes. Harvest of tuberous orchids has recently been raised in Iran owing to the high prices of orchid's tubers and international demand from neighboring countries. This has caused competition among orchid harvesters in the country so that the orchids are not even allowed to produce seeds. The present study was done aimed at protecting and identifying the phenotypic diversity within Orchis mascula genotypes in Abr forest, which is a natural habitat of Orchis mascula in Shahrood area, Northeast Iran. The morphological variability of 101 collected samples of early purple orchids was analyzed based on a total of 57 morphological traits. In terms of the quantitative traits, the highest and lowest coefficients of variation (CV%) were observed in the number of side tubers (200%) and petal length (14.43%), respectively. When it comes to the qualitative traits, the highest and lowest CVs were observed in lip color (70.90%) and the flower form on the stem (0%), respectively. Among the studied traits, 11 attributes showed a CV value of less than 20%. The highest positive correlations were observed between tuber fresh weight and tuber dry weight (r = 0.908). Applying principal component analysis (PCA) indicated three main components that explained 45.81% of the total variance. The clusters number four and seven could arguably be suitable sources of parents in breeding crosses for tuber fresh and dry weight traits. In summary, this study confirmed that Abr forest would be one of the rich diversity areas for Orchis mascula and our findings might be satisfactorily applied for breeding, conservation, domestication and development of new traits depending on different breeding purposes.

Common medlar (Mespilus germanica L.) is one of the latest maturating fruits and its fruit is used as a nutrition component and as a medicinal remedy. The present investigation was carried out to evaluate the morphological variability of 103 accessions of this species. The significant differences were detected among the accessions based on the measured morphological characters. Fruit length ranged from 14.91 to 23.68 mm, and fruit width varied from 14.21 to 23.46 mm. Moreover, 10 fruit weight ranged between 15.00 and 55.87 g with an average of 30.86. Fruit yield was positively correlated with tree vigor, tree canopy size, and branching, while it was negatively correlated with suckering. Principal component analysis (PCA) showed that 74.48% of the variability observed was explained by the 11 components. The dendrogram created using cluster analysis grouped the accessions into two major clusters. The current finding showed that natural populations of medlar were diverse suggesting they are a high genetic potential, which could be used from the agronomic point of view to find several valuable well-adapted genotypes suitable for substantial improvement of the production. Thus, it is necessary to preserve the present available genetic material.

Pyrus boissieriana appears to be a promising species for its use as rootstock for the commercial pear (P. communis L.) in lowland areas prone to drought and flooding. The current study was conducted on the evaluation of phenotypic diversity among 102 accessions of wild pear (P. boissieriana). The accessions studied showed significant differences in terms of all the measured characters. The leaf length ranged from 19.33 to 51.33 mm and leaf width varied from 17.13 to 48.75 mm. The fruit length ranged from 8.26 to 22.51 mm and the range of 10 fruit weight was from 2.48 to 72.00 g. Fruit weight showed positive correlations with bunch length, bunch weight, fruit length, and fruit width. Principal component analysis (PCA) showed that the first eight PCs explained 80.47% of the total variance and the characters such bunch weight, fruit length, fruit width, fruit diameter, fruit weight, and fruit flesh length were the key characters in the present data set, which differentiated the accessions belonging different areas. The dendrogram obtained based on the measured characters grouped the accessions into three main clusters and indicated the existence different levels of morphological variation among the accessions, which is applicable and useful for pear breeding programs. The finding obtained here confirmed that the northern and northeastern parts of Iran are rich sources of pear genetic diversity which this valuable gene pool should be in situ and ex situ conserved.

Mulberry (Morus spp.) has always been a favorite plant of gardners, farmers and researchers because of its edible fruits, medicinal properties and timber. We have investigated the morphological, physiological and chemical variabilities of white (Morus alba), red (Morus rubra) and black (Morus nigra) mulberry genotypes grown in four regions of Iran. Among the genotypes assessed, fresh fruit weight varied between 3.2 and 87.9 g, total chlorophyll ranged from 4.3 to 13.4 mg/g fresh weight and vitamin C content ranged from 5.5 to 64 mg per 100 g. The highest and lowest antioxidant activity was 275 and 1575 mg ascorbic acid equivalent (AAE) 100 g−1 fresh weight, respectively. The population analysis indicated that the Gorgan population, in terms of morphological and physiological traits, and Shahrood population, in terms of chemical traits, had the highest coefficient of variation. Correlation analysis showed that fruit size and taste were positively correlated with foliar traits and that phenolic content was positively correlated with both antioxidant activity and total soluble solids (TSS). Of the indices assessed, the Berger–Parker index was the most valuable because it was able to identify significant differences between populations in terms of the studied traits. The results of this study confirm that Iran is one of the mulberry phenotypic and biochemical diversity areas and provide information of possible use for the development, conservation and selection of parents for cross-combinations in breeding programs.

Low back pain is one of the most common causes of referral to physicians. Lumbar disc degeneration (LDD) is the main cause of back pain in different countries. It seems that genetic factors are more effective than environmental factors in the developing of degenerative phenomena. The aim of this investigation, therefore, was to study the association of the aggrecan gene (In this study, 55 patients with symptomatic intervertebral disk degeneration and 55 control subjects were included. VDR gene polymorphism was genotyped by PCR-based RFLP. The isolated DNA was used to genotype the VNTR of ACAN gene via conventional PCR.For VDR gene polymorphism, the CC genotype (OR=5.337, P=0.019) was significantly higher among the patients compared with the controls, revealing a higher frequency of the C allele in patients compared with controls (OR=2.707, P=0.005). The lower number of frequent repetitions in the VNTR aggrecan gene was associated with a six-time increase of lumbar disc degeneration. Also, high BMI can be considered as an independent factor in the incidence of this disease.Aggrecan gene VNTR polymorphism had an association with degeneration of lumbar intervertebral discs that the shorter VNTR repeats increasing the chance of the disc degeneration in this population in the North of Iran. Moreover, an association between the mutant allele (C) of VDR gene