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A successful management and preservation of the natural populations depend on accurate assessment of genetic diversity. Knowing the genetic diversity within a population is important for choosing the conservation strategies for the species. The genus Carpinus belonging to Coryloideae, Betulaceae, has significant economic and ornamental importance. Determination of the taxa in the genus Carpinus in Iran is one of the most controversial issues among the researchers; for example, we can see this claim in the recent botanical literatures such as Sabeti and Browicz. However, two good species namely C. betulus L. and C. orientalis Mill. are the main species in Iran, adjacent regions and also in Europe. In general, taxonomic and biosystematics studies of the Carpinus are not known in Iran, moreover, in few cases, inter-specific hybrids and intermediate forms are recognised. A detailed molecular (ISSR) study of the Carpinus is done here with the following objectives: 1) to delimitate the species; 2) to carry out population genetic study and produce information on genetic structure, genetic variability within each population in Carpinus betulus and C. orientalis. In present study, 85 randomly collected plants from 17 geographical populations of two Carpinus species were considered. Our results indicated that ISSR markers can be used as a reliable and informative technique for evaluation of genetic diversity and relationships among Carpinus species.
In this study, palynological characteristics of 23 specimens of Helichrysum Mill., representing 12 Iranian species were investigated. We evaluated pollen grains (25 per specimens) and tested them by 15 qualitative and quantitative characteristics using Scanning Electron Microscopy (SEM). Pollen grain descriptions of most species were presented for the first time in the world. The pollen grains were tricolporate, radially symmetrical and isopolar in all examined samples. They were small, and rarely medium in size. The polar outline view (amb) was the same among the species. The overall views of pollen grains were prolate-spheroidal, oblate-spheroidal, subprolate, prolate and spheroidal. However, the more abundant type was prolate-spheroidal. The exine sculpture was echinate, and tectum is perforate. The ANOVA test revealed a significant variation (P < 0.001) for all the quantitative characteristics. In PCA analysis, the colpus length, width, and length/width ratio traits, polar and equatorial axes length, were the most variable features and some species were characterised by these characters. Results indicated that a few qualitative characteristics such as polar outline view and exine sculpture lack taxonomic importance via their stability among species. Also, the palynological traits had enough potential to separate the taxonomic boundaries of H. rubicundum and H. globiferum, but approximately the species clustering pattern did not agree with Flora Iranica.
Haloxylon aphyllum is a significant species adapted to salinity conditions and plays an important role in stabilising soil, providing forage, and serving as a source of firewood for residents. In this study, the genetic diversity of four populations of H. aphyllum in Iran was examined using four primers to assess genetic diversity, which produced a total of 41 bands. The AMOVA test showed that the studied populations differed in their genetic content. Specifically, 46% of genetic variability occurred within populations, while 54% arose between populations, indicating a high degree of genetic variation among H. aphyllum populations. The Mantel test presented a significant correlation between genetic distance and geographic distance. Additionally, the STRUCTURE analysis presented comprehensive information on the genetic structure of the studied H. aphyllum populations. The presence of genetic diversity and heterozygosity among H. aphyllum populations suggests local adaptation among populations, which may be due to the heterogeneity of environmental factors such as soil moisture and nutrients that create genetic heterogeneity.
A safflower disease was observed in the fields of South Khorasan (Iran) in 2017–2018. Affected plants had extensive fasciation, bushy growth, small leaves, phyllody and shortened internodes. Polymerase chain reaction (PCR) assays were performed using universal phytoplasma primers pairs P1/P7, R16mF1/mR1 and M1/M2 to detect putative phytoplasma (s). Nested PCR analyses showed that all symptomatic plants were positive for phytoplasma infection, while asymptomatic plants were negative. Nucleotide sequence analysis and RFLP analyses of PCR-amplified 16S rDNA sequences indicated that safflower fasciation in Iran was associated with a phytoplasma that belonged to the peanut witches' broom group (16SrII). Phylogenetic analysis confirmed that safflowers fasciation phytoplasma (SaP) must be classified in ‘Candidatus phytoplasma aurantifolia’ (16SrII) taxonomic group. To our knowledge, this is the first documentation of a phytoplasma associated with safflower fasciation in Iran and the world.
. Wetland Ecology: Principles and Conservation. Keddy, P. A. and P. MacLellan. 1990. Centrifugal organization in forests. Oikos 59:75-84. Centrifugal
Connell, J.H. and R.O. Slatyer. 1977. Mechanisms of succession in natural communities and their role in community stability and organization. Am. Nat. 111:1119–1144. Slatyer R
Cultured plant cells of Marchantia polymorpha were examined for their ability to reduce β-keto ester, 2-methyl-3-oxobutanoate. The cells reduced ethyl 2-methyl-3-oxobutanoate to predominantly yield the anti -product, ethyl (2 S ,3 S )-3-hydroxy-2-methylbutanoate, with 92% diastereomeric excess and over 99% enantiomeric excess. The use of immobilized cells of M. polymorpha in calcium alginate gel improved the diastereomeric excess of the product (97% de). In addition, the large-scale reduction of 75 g of ethyl 2-methyl-3-oxobutanoate with immobilized M. polymorpha gave the product with 97% de and >99% ee in 92% yield.
to a classification system performed by International Organization for Biological Control (IOBC) ( Hassan, 1992 ). This classification system included class 1 that meant by harmless at mortality percentages of <30%, class 2 meant by slightly harmful
Keddy, P.A. and P. MacLellan. 1990. Centrifugal organization in forests. Oikos 59:75–84. MacLellan P. Centrifugal organization in forests Oikos
Widder , S. , K. Besemer , G.A. Singerb , S. Ceolae , E. Bertuzzof , C. Quinceg , W.T. Sloang , A. Rinaldof and T.J. Battin . 2014 . Fluvial network organization imprints on microbial co-occurrence networks . Proc. Nat. Acad. Sci. USA 111
