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Hazelnuts are glycophytic and sensitive plants to salt, especially to chloride ion. However, the genotypes might be different in responses to salt stress. This search attempted to understand the behavior of four hazelnut commercial widely grown cultivars ('Segorb', 'Ronde de Piemant', 'Fertile de Coutard' and 'Negret') under salinity stress. The experimental four-year-potted plants were treated with four levels of NaCl (0, 30, 60, and 90 mM). Variations were found in the values of morphological and physiological indicators between the studied cultivars. The 'Fertile de Coutard' leaves contained the lowest accumulation of sodium (0.48%) and chloride (1.1%) of dry weight (DW)), a high potassium content (1.4% DW), the smallest decrease of Fv/Fm (15.85% at 90 mM K+/Na+ ratio (2.91% DW), the lowest decrease in the relative water content (RWC) (22.5%), the highest proline content (4 μmol g−1) of fresh weight (FW), and a low amount of lipid peroxidation (0.6 μmol g−1 FW) compared to other cultivars. On the contrary, 'Segorb' contained the highest chloride content (1.63% DW), and recorded the greatest decrease of Fv/Fm (45.12% at 90 mM NaCl) and K+/Na+ ratio (1.45% DW). Changes in the expression rate of the studied transcription factors (TF) were observed. The drought-responsive element binding (DREB) transcript level significantly increased after 12 h in 'Fertile de Coutard', and 72 h in 'Segorb'. The APETALA2/ethylene-responsive factor (AP2/ERF) transcript abundance reached the highest level after 72 h of treatment in 'Fertile de Coutard', while it did not change in 'Segorb'. Thus, our results indicate that the 'Fertile de Coutard' has the greatest potential to resilient salinity stress among the studied cultivars. [ABSTRACT FROM AUTHOR]

Pomegranate (Punica granatum L.) fruit quality depends on many traits including visual, biochemical and mineral characteristics. One of the negative traits is aril whitening (AW) which is a frequently observed disorder in hot and dry climates, that leads to decline in desirable fruit quality. Color, antioxidant, and mineral contents of the arils are of prime importance as quality traits. Therefore, this study aims to investigate the effect of shading and foliar minerals on fruit quality during the fruit development stages of pomegranate. Treatments included shaded (50% green net) and unshaded trees and foliar application of trees with potassium sulfate (K, 1% and 2%) or sodium silicate (Si, 0.05, 0.1 and 0.15%) during two growing seasons. Results showed that the severity of AW at harvest decreased significantly when trees were covered with shading compared to control. The color values of L* and ⁰hue for arils were lower in fruits grown under shading conditions indicating darker red arils. Shading significantly reduced chilling injury in cold storage compared to open field fruits. Shading and Si 0.15% increased superoxide dismutase, and catalase enzymes activity while decreased Polyphenol oxidase and peroxidase. Covering trees with shading and Si 0.15% spray resulted in the highest total anthocyanin, antioxidant activity, and total phenolics content in the arils. Shading as well as Si 0.15% increased macronutrients content of the arils. The study concluded that covering pomegranate trees and spraying with Si in hot climate reduced AW, increased antioxidant traits, and led to higher fruit quality. [ABSTRACT FROM AUTHOR]

Non-erroneous and well-optimized transcriptome assembly is a crucial prerequisite for authentic downstream analyses. Each de novo assembler has its own algorithm-dependent pros and cons to handle the assembly issues and should be specifically tested for each dataset. Here, we examined efficiency of seven state-of-art assemblers on ~ 30 Gb data obtained from mRNA-sequencing of Thymus daenensis. In an ensemble workflow, combining the outputs of different assemblers associated with an additional redundancy-reducing step could generate an optimized outcome in terms of completeness, annotatability, and ORF richness. Based on the normalized scores of 16 benchmarking metrics, EvidentialGene, BinPacker, Trinity, rnaSPAdes, CAP3, IDBA-trans, and Velvet-Oases performed better, respectively. EvidentialGene, as the best assembler, totally produced 316,786 transcripts, of which 235,730 (74%) were predicted to have a unique protein hit (on uniref100), and also half of its transcripts contained an ORF. The total number of unique BLAST hits for EvidentialGene was approximately three times greater than that of the worst assembler (Velvet-Oases). EvidentialGene could even capture 17% and 7% more average BLAST hits than BinPacker and Trinity. Although BinPacker and CAP3 produced longer transcripts, the EvidentialGene showed a higher collinearity between transcript size and ORF length. Compared with the other programs, EvidentialGene yielded a higher number of optimal transcript sets, further full-length transcripts, and lower possible misassemblies. Our finding corroborates that in non-model species, relying on a single assembler may not give an entirely satisfactory result. Therefore, this study proposes an ensemble approach of accompanying EvidentialGene pipelines to acquire a superior assembly for T. daenensis. [ABSTRACT FROM AUTHOR]

Fruit growth patterns are often exploited in predictions of final fruit size and to inform planting and harvesting decisions. Ten local apricot (Prunus armeniaca) varieties with superior genotypes (two early-ripening, five mid-ripening and three late-ripening varieties) were assessed using 20 nonlinear regression models (NRMs) and a radial basis function (RBF) neural network model. Fruit diameter and weight measurements for each genotype were collected at four-day intervals from fruit set to commercial harvest. Patterns based on diameter and weights were attributed to each genotype. Among the NRM tested, only four were able to flawlessly predict apricot diameter and weight during the growing season. In addition, comparison of nonlinear regression methods with the neural network indicated than the RBF model displayed fewer prediction errors than the NRMs. The RBF model predicted fruit size with a coefficient of determination (R2 value) greater than 0.95. Therefore, predictions of growth patterns in fruit trees can be accomplished with neural network modeling. [ABSTRACT FROM AUTHOR]

Lilium ledebourii (Baker) Boiss is a rare species, which exhibits valuable traits. However, before its genetic diversity and evolutionary were uncovered, its wild resources were jeopardized. Moreover, some ambiguities in phylogenetic relationships of this genus remain unresolved. Therefore, obtaining the whole chloroplast sequences of L. ledebourii and its comparative analysis along with other Lilium species is crucial and pivotal to understanding the evolution of this genus as well as the genetic populations. A multi-scale genome-level analysis, especially selection pressure, was conducted. Detailed third‑generation sequencing and analysis revealed a whole chloroplast genome of 151,884 bp, with an ordinary quadripartite and protected structure comprising 37.0% GC. Overall, 113 different genes were recognized in the chloroplast genome, consisting of 30 distinct tRNA genes, four distinct ribosomal RNAs genes, and 79 unique protein-encoding genes. Here, 3234 SSRs and 2053 complex repeats were identified, and a comprehensive analysis was performed for IR expansion and contraction, and codon usage bias. Moreover, genome-wide sliding window analysis revealed the variability of rpl32-trnL-ccsA, petD-rpoA, ycf1, psbI-trnS-trnG, rps15-ycf1, trnR, trnT-trnL, and trnP-psaJ-rpl33 were higher among the 48 Lilium cp genomes, displaying higher variability of nucleotide in SC regions. Following 1128 pairwise comparisons, ndhB, psbJ, psbZ, and ycf2 exhibit zero synonymous substitution, revealing divergence or genetic restriction. Furthermore, out of 78 protein-coding genes, we found that accD and rpl36 under positive selection: however, at the entire-chloroplast protein scale, the Lilium species have gone through a purifying selection. Also, a new phylogenetic tree for Lilium was rebuilt, and we believe that the Lilium classification is clearer than before. The genetic resources provided here will aid future studies in species identification, population genetics, and Lilium conservation. [ABSTRACT FROM AUTHOR]

Climate change and population increase are two challenges for crop production in the world. Hazelnut (Corylus avellana L.) is considered an important nut regarding its nutritional and economic values. As a fact, the application of supporting materials as foliage sprays on plants will decrease biotic and abiotic stresses. In this study, the effects of salicylic acid (0, 1 mM and 2.5 mM) and kaolin (0, 3% and 6%) sprays were investigated on morphological, physiological, pomological, and biochemical characteristics of hazelnut. The results showed that 1 mM salicylic acid and 6% kaolin had the best effects on nut and kernel weight compared to control. Biochemical parameters such as chlorophyll a, b, a + b, and carotenoid contents showed that salicylic acid and kaolin improved pigment concentration. Proline and antioxidant contents such as phenolic acids, SOD, APX, and CAT enzyme activities increased by these applications. On the other hand, lipid peroxidation, protein content, and H2O2 content were decreased. Based on the tolerance index result, Merveille de Bollwiller cultivar showed the highest tolerance while 'Fertile de Coutard' had the lowest value. Therefore, hazelnut performance may be improved through exogenous application of the signaling (salicylic acid) and particle film (Kaolin) compounds in warmer climates. [ABSTRACT FROM AUTHOR]

The morphological variation and essential oil content of 150 individuals of motherwort ( Leonurus cardiaca) from six natural regions of Iran were examined biometrically based on multivariate analysis. The highest variation was observed in plant height, length of main stems, main inflorescence length, floral cycles of main stem, lateral branches length, basal leaf length, floral leaf length width, flower length, and calyx color. Results of simple correlation analysis showed the existence of significant positive and negative correlations among some important parameters. The highest correlation was observed between plant height and length of main stems and between lateral branch length and lower surface color of leaf. Populations were clustered in two groups representing subspecies cardiaca and persicus. The subspecies cardiaca populations were closely related with each other and differentiated from the subspecies persicus by pubescence stems and leaves, more number of floral cycles, higher compaction of floral cycles, lower number of lateral branches, shorter length of petioles and leaves and smaller floral leaves. Essential oil yields varied from 0.02 (for Taleghan population) to 0.053 mg/100 g dry mater (for Kerman population). The conservation of the highly diverse native populations of Iranian motherwort germplasm is recommended. [ABSTRACT FROM AUTHOR]

Subgenus Cerasus species are useful genetic resources for cherry breeding programs. A total of 17 morphological traits together with 19 random amplified polymorphic DNA (RAPD) primers were used to study 39 accessions including 34 wild Cerasus subgenus genotypes belonging to Prunus avium L., P. cerasus L., P. mahaleb L., P. microcarpa Boiss., P. incana Pall., and P. brachypetala Boiss. species, along with an unknown wild Cerasus sample, two advanced cherry cultivars ('Lambert' and 'Bulgar'), and two rootstocks ('Colt' and 'Gisela 6'). Genotypes were separated into different groups according to their species and collection sites using cluster analysis performed by Ward's clustering method based on morphological data. Nineteen RAPD primers from 60 screened produced 304 polymorphic reproducible bands (98.15% polymorphism). According to the similarity matrix, the lowest similarity was obtained between P. avium and P. microcarpa samples. A dendrogram was prepared by the unweighted pair-group method with arithmetic average (UPGMA), and the accessions were separated according to their species and geographic origin. In both morphological and molecular results, the advanced cultivars and rootstocks were separated from wild genotypes, and the unknown genotype was grouped with P. mahaleb accessions. Grouping by morphological characteristics was compared with the results of RAPD analysis, with no significant correlations between morphological and molecular data being found. This is the first report of molecular (RAPD) genetic diversity study in wild Cerasus subgenus genotypes from Iran, and the results demonstrate the high potential of RAPD analysis for discrimination of Cerasus subgenus genotypes. [ABSTRACT FROM AUTHOR]

Almond and its related wild species, which are widely distributed in Central and West Asia, have high genetic variation. This is an important source of genetic diversity for crop improvement. In this study a set of 32 SSR and 12 EST-SSR primer pairs were used to determine genetic diversity in 89 accessions of almond and other Prunus species. Most of the accessions (68) were collected from natural habitats of Iran. SSR primers amplified higher numbers of alleles than EST-SSR markers and discriminated genotypes more effectively. Results indicated high diversity among accessions. Observed heterozygosity (Ho) was 0.581. Nei's index of diversity (He) and average number of alleles per locus (na) were 0.885 and 34, respectively. The mean value of polymorphism information content (PIC) was 0.874. The average Fst (F-statistics index) was 0.271 and the fixation index (Fis) was 0.151. Estimated variance among putative populations (AP) and individuals (AI) and within individuals (WI) were 5, 35, and 60%, respectively, which revealed that most of the variation was distributed among individuals rather than groups. Cultivated almonds were highly similar to P. fenzeliana, which is native to West Asia, supporting the importance of these regions in almond domestication. In the dendrogram of groups, minimum genetic distance was observed between Amygdalus and Orientalis groups from the Euamygdalus section. The Leptopus and Chameamygdalus sections were more distant from almonds than plums. The results also showed Dodecandra ( Lycioides) series should be taxonomically classified closer to the section Euamygdalus. [ABSTRACT FROM AUTHOR]

The amplified fragment length polymorphism (AFLP) technique was used to examine the genetic relationships among 21 Iranian soft-seeded pomegranate ( Punica granatum L.) genotypes. Out of 72 fluorescent-AFLP primer combinations screened, 31 were selected to produce the 503 polymorphic markers used in this study. Genetic similarity estimates between genotypes, calculated by the Jaccard's similarity coefficient, ranged from 0.17 to 1.00, while the cophenetic correlation coefficient between the genetic similarities and the unweighted pair group method of arithmetic averages (UPGMA) dendrogram was 0.98. The AFLP-based UPGMA dendrogram revealed two groups within the genotypes at 0.33 similarity coefficient, which reflect fruit traits such as peel and aril color, and seed firmness, as well as region of origin. Our study shows that the use of molecular markers is essential during all steps of germplasm management to avoid genotype redundancy and mislabeling. The present study will be used as a reliable reference to discriminate among these genotypes, to aid management of germplasm collections used to breed new varieties for the Iranian pomegranate industry. [ABSTRACT FROM AUTHOR]

The article discusses a study on the use of morphological traits and random amplification of polymorphic DNA (RAPD) markers in describing Iranian and foreign walnut genotypes. It was found that RAPD markers are efficient methods of studying genetic diversity of walnut genotypes. The study concluded that the genotypes can be directly used as material or parents in walnut improvement programs.

Bunch wilting, a disorder of date palm (Phoenix dactylifera L.) and caused by climatic factors (low relative humidity along with high temperatures), critically damages its production in Iran. In this study, the effects of 5-aminolevulinic acid (5-ALA) as precursor of chlorophyll and elicitor of antioxidants applied to be involve directly or indirectly in stress tolerance mechanisms, bunch wilting severity, and other physiological aspects on 10-12 years old date palm in two locations. 5-ALA concentrations included 0 (control), 200, 240 and 280 ppm, applied as aqueous solution at biweekly intervals from fruit set until the beginning of fruit Kimri stage on leaves around the fruit bunches (for three times). Results showed that the yield of trees and bunch weight increased; hydrolytic enzymes activities in stalk and fruit decreased and activities of peroxidase, superoxide dismutase, and catalase, important enzymes of the antioxidative system were increased. The plants’ redox state changed as identified by decrease in H2O2 and proline of fruits. Microelement concentrations of leaves were changed at damage stage. Perhaps, due to mild environmental conditions in location A, lower bunch wilting and better physiological conditions of fruits recorded compared to location B. Foliar application of 5-ALA resulted to a coordinated action of the antioxidative system, affecting the defense-related enzymes. The treatment caused biosynthesis of chlorophyll and adjustments in H2O2 and proline compositions in leaf, stalk, and fruit. Bunch wilting was alleviated by 240 ppm 5-ALA, moderating the response of tree load to environmental stress conditions. [ABSTRACT FROM AUTHOR]