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Fruit cracking and sunburn are two major disorders that can negatively impact pomegranate (Punica granatum L.) production. To address these problems, an experiment was conducted to evaluate the combined effects of silica (0, 100, 300, and 500 ppm) and calcium nitrate (0, 0.75%, and 1.5%) spraying on the fruit of 'Malase-Saveh' pomegranate. The treatments were applied three times during the growing season and a factorial experiment was conducted based on the completely randomized block design. The results indicate that most of the qualitative and quantitative traits were influenced by foliar spraying of these substances. Furthermore, the results demonstrated that foliar application of silica, calcium nitrate, and their interaction significantly affected fruit cracking. The lowest fruit cracking (1.06%) was obtained by spraying 500 ppm silica and 1.5% calcium nitrate, while the highest fruit cracking (21.6%) was recorded from untreated plants. The highest fruit weight (215.4 g) was observed in the treatment 1.5% calcium nitrate. Most of the treatments had a positive effect on fruit weight and increased it compared to the control. Moreover, the treatments improved some qualitative characteristics, such as an increase in fruit acidity and decrease in sunburn disorder. Ultimately, this study concluded that combined spraying of silica with calcium is more effective than individual use and results in the highest fruit yield and quality, as well as the lowest cracking and sunburn disorders. These findings suggest there are synergistic effects between these compounds. [ABSTRACT FROM AUTHOR]

This experiment was conducted to investigate the impact of foliar spraying salicylic acid (SA) and methyl Jasmonate (MJ) on the physiology responses of strawberry (Fragaria × ananassa cv. 'Camarosa') grown under salinity stress. According to results, SA and MJ significantly reduced the injuries caused by salt stress, possibly through promoting K+ accumulation as well as decreasing the electrolyte leakage and Na+ contents in the leaves. The best protective effects resulted from 0.75 mM SA and 0.25 mM MJ treatments. These results indicate that SA and MJ can effectively improve the defense system and antioxidant capacity of strawberry in the salt affected environments. [ABSTRACT FROM AUTHOR]

Simple sequence repeat (SSRs) markers derived from Malus were used to assess their transferability in the analysis of the genetic diversity and relationship of some Pyrus species. All studied microsatellite loci produced fragments and were polymorphic among the studied samples. Fifty-one allelic variants were detected at eight SSR loci, ranging from five (MS14h03, CH02b10 and CH03g06) to nine (CH02h11a), with a mean of 6.37 alleles per locus. A relatively high level of diversity was recorded among the studied accessions. The average of Shannon's index (I) was 1.04. The Dice genetic similarity coefficient ranged greatly and ‘Khoj 1’ (a member of P. communis) and ‘Shinko’ (a cultivar belonging to P. pyrifolia) had the lowest (0.21) values, while ‘Chojuro’ and ‘Nijisseiki’, two cultivars belonging to P. pyrifolia, had the highest genetic similarity (0.97) among the studied samples. Bayesian cluster analysis and principal coordinates analysis plot separated the P. pyrifolia samples from other species, and formed three distinct groups, indicating high genetic differences between P. pyrifolia and other studied pear species. Several private alleles were observed in some of the studied species that would be of great importance for species identification. Furthermore, in 23 samples, more than two alleles were observed in the CH04e03 locus, indicating presence of locus duplication in these samples. Our observations suggest that, for this locus, at least two homologous chromosomes or genomic regions may be presented in the genome of some pear samples. [ABSTRACT FROM AUTHOR]

Pomegranate is a long-cultivated fruit tree believed to have originated in Iran. In the present study, 16 preselected nuclear microsatellite markers, or simple sequence repeats (SSRs), were analyzed in 50 pomegranate (Punica granatum L.) accessions from five regions in Fars province of Iran. Each SSR loci was polymorphic and produced 48 fragments in the studied samples. The mean expected and observed heterozygosity of the 16 SSR loci was 0.33 and 0.48, respectively. The polymorphic information content ranged from 0.18 to 0.58 with an average of 0.41. There were some differences regarding diversity indices among populations, and several private alleles were detected in different populations, indicating the importance of these accessions for genetic conservation. Cluster analysis using SSR data grouped genotypes largely based on their geographical origins. Analysis of molecular variance showed that most of the genetic variation was among populations. Genetic synonymy was observed in some pomegranate accessions located across geographical regions. A relatively high level of genetic admixture was found among accessions from different regions, suggesting that there is a high level of genetic exchange between individual genotypes. This work assesses the genetic diversity and population structure of pomegranates in Fars province, which assists in future conservation and breeding programs. [ABSTRACT FROM AUTHOR]

To find out more about the biochemical aspects of seed-softness trait in pomegranate (Punica granatumL.), some of the phenylpropanoid pathway enzymes as well as their products were evaluated in the various soft- and hard-seeded genotypes during fruit development. Results showed that peroxidase (POD) activity decreased in all studied genotypes during fruit growth, while increasing at the last stages only in the hard-seeded genotypes. Although laccase (LAC) activity did not show high differences during fruit ripening and in different genotypes, but its general trend was increasing. Phenylalanine ammonia-lyase (PAL) activity decreased during the fruit development and approximately diminished for the hard-seeded genotypes. All genotypes had lignin components in their seeds and amount of lignin increased during the growth season. Total phenolic decreased drastically and antioxidant capacity increased gradually showing an opposite trend and probable competitive effect for the same substrate during fruit development. Considerable differences that were observed in the POD activity at the last sampling stage, and higher activity that was observed in POD than LAC, may indicate that POD is more important for polymerization of lignin in the pomegranate seed and this enzyme might have some role in the development of seed softness trait in pomegranate. Also, this is the first report about lignin detection in the seeds of soft-seeded pomegranate genotypes, and represents a different mechanism (such as monolignol conformation in the final polymer) from lignin content for development of the soft-seeded pomegranate genotype. [ABSTRACT FROM PUBLISHER]

The article describes a study which examined genetic relationships among some cultivated and a wild pomegranate accessions in Iran. The genetic relationships were determined using randomly amplified polymorphic DNAs (RAPDs) and simple sequence repeats (SSRs) molecular markers. The study found that the wild accession of pomegranate was genetically different from domesticated pomegranates.

The effects of three levels of drought stress [100%, 75% and 50% field capacity (FC)] and different concentrations of TiO2 nanoparticles (0, 5, 10, 20, 30, 50, 100, and 150 ppm) were assessed on the different metabolites of Moldavian dragonhead plant, an important ornamental, medicinal and aromatic herb. Results of high-performance liquid chromatography analysis of Moldavian dragonhead extract showed that among 14 detected compounds in the chromatogram, rosmarinic acid was the most frequent and followed by chlorogenic acid, acacetin-7-O-glucoside and apigenin-7-O-glucoside. Drought stress affected some of the metabolites and the highest values of rosmarinic, chlorogenic and p-cumaric acids were recorded in the moderate drought stress (75% FC), while in the higher drought stress (50% FC) some compounds such as caffeic acid and apigenin were increased and some other including ellagitannin and gentisic were decreased. Plant dry weight was also decreased under drought stress while essential oil content was increased. Production of studied metabolites was also influenced by application of TiO2 nanoparticles. Among different concentrations of TiO2 nanoparticles, 30, 50 and 100 ppm showed to be the most effective concentrations. Although TiO2 treatment did not significantly affect plant dry weight, the essential oil content was increased by this treatment and the highest value was obtained after treatment with 30 ppm of TiO2. According to our results, both drought stress and TiO2 nanoparticle treatments are able to increase some valuable phenolic substances including rosmarinic acid and chlorogenic acid in Moldavian dragonhead plant. Altogether, drought stress at 75% FC and TiO2 nanoparticles at concentrations of 30-50 ppm can increase phenolic bioactive compounds of Moldavian balm. New findings possibly would suggest a practical application of controlled drought stress and TiO2 nanoparticles in the culture of Moldavian balm with the purpose of increasing phenolic compounds. [ABSTRACT FROM AUTHOR]

Carob moth, Ectomyelois ceratoniae Zell (Lep.: Pyralidae), is the most important pest in Iranian pomegranate orchards and imposes tremendous annual economic loss to the pomegranate producers. A two-year study was conducted to investigate the effects of the utilization of different fertilizers on the carob moth infestation of pomegranate cv. ‘Bajestani’. Fertilizer programs significantly affected fruit infestation. The highest infestation rate was recorded in unfertilized plants (38.07%, 31.44% in the first and the second years, respectively). Among different treatments, chemical and humic fulvic-containing fertilizers proved to be the most efficient treatments for controlling carob moth. A Significant correlation was observed between carob moth infestation and various fruit and tree-related attributes. The peel hardness and its hardness-associated nutrients (Ca, K and Si), as well as total phenolic content of fruit juice, were among the factors that showed a high negative correlation with carob moth infestation. According to our results, a combination of organic and Si, Ca, and K-containing fertilizers has great practical potential in the management of pomegranate orchards to reduce the carob moth damages. [ABSTRACT FROM AUTHOR]

Limiting the juvenile phase and reducing tree size are the two main challenges for breeders to improve most fruit crops. Early maturation and dwarf cultivars have been reported for many fruit species. "Early mature" and low vigor walnut genotypes were found among seedlings of Persian walnut. Nine microsatellite markers were used to evaluate genetic diversity among "Early Mature" Persian walnut accessions and provide a comparison with "normal growth" accessions. Six maturation related characteristics were also measured in "Early Mature" samples. Phenotypic traits and diversity indices showed relatively high levels of genetic diversity in "Early Mature" seedlings and indicated high differentiation between individuals. Seedling height, the most diverse phenotypic trait, has an important role in the clustering of "Early Mature" accessions. The "Early Mature" type had higher number of alleles, number of effective allele, and Shannon index compared to the "Normal Growth" group. The two types of studied walnuts had different alleles, with more than half of produced alleles specific to a specific group. "Early Mature" and "Normal Growth" walnuts had 27 and 17 private alleles, respectively. Grouping with different methods separated "Early Mature" and "Normal Growth" samples entirely. The presence of moderate to high genetic diversity in "Early Mature" walnuts and high genetic differentiation with "Normal Growth" walnuts, indicated that "Early Mature" walnuts were more diverse and distinct from "Normal Growth" samples. Moreover, our results showed SSR markers were useful for differentiating between "Early Mature" and "Normal Growth" walnuts. A number of identified loci have potential in breeding programs for identification of "Early Mature" walnuts at the germination phase., Competing Interests: The authors declare there are no competing interests.