Single sequence repeat markers associated with partial resistance in sunflower to Phoma macdonaldii

Phoma black stem of sunflower, caused by Phoma macdonaldii, occurs in many countries. The objective of the present study was to estimate the number of markers and genomic regions in sunflower associating with Phoma black stem resistance. Genetic variability among 32 sunflower genotypes, including recombinant inbred lines and their parents, M7 mutant lines developed by gamma irradiation, and some genotypes from different countries of origin, was evaluated using simple sequence repeat (SSR) markers. Eighty-eight markers were generated at 38 SSR loci, with a mean number of alleles per locus of 2.32. Using susceptibility data of 32 sunflower genotypes against seven P. macdonaldii isolates (Darvishzadeh et al., 2007), one to four markers were associated with each of seven different P. macdonaldii isolates. To reduce the probability of false positives, a sequential Bonferroni-experiment-wise P-value was used for each marker trait association tested. The identified markers showed a promising trend, although they did not pass the more stringent bar of statistical significance, and should be studied further

Foliar Applications of ZnO and Its Nanoparticles Increase Safflower (<i>Carthamus tinctorius</i> L.) Growth and Yield under Water Stress

Foliar application or minerals is a methodology to promote growth and/or yield and to protect plants against different kinds of stresses. Currently there is a great interest in evaluating the effect of nanoparticles for enhancing the effect of these treatments. This study was performed to evaluate and compare the effect of foliar application of zinc oxide (ZnO) and zinc oxide nanoparticles (ZnO-NPs) on the growth and yield of safflower under different irrigation regimes. Foliar applications of ZnO in all concentrations (4, 6, 8, 10, 12, and 14 g L−1) led to an increase in biomass yield, number of capitula per plant, number of seeds per capitulum, and grain yield of plants compared with control plants. The maximum increase in the studied traits was obtained with a ZnO concentration of 6, 8, and 10 g L−1. In a second round of experiments, we observed the effect of nanoparticles and found that spraying with ZnO and ZnO-NPs at a concentration of 10 g L−1 may ameliorate the deleterious effects of water deficit. The results of the present study support the idea that foliar application of ZnO improves safflower yield, especially under drought stress, and showed that using of nanoparticles increases the efficiency of the application

Genetic Diversity of Trichoderma harzianum Isolates in Sunflower Rhizosphere: The Application of the URP Molecular Marker

The genetic diversity of 77 Trichoderma harzianum isolates collected from sunflower rhizosphere soils in Urmia, Khoy, and Salmas in West Azerbaijan province, Iran, was evaluated by using the Universal Rice Primer (URP) molecular marker. The DNA band pattern of the isolates was developed using seven primers of this marker. These primers produced 186 gene loci, out of which 182 loci were polymorphic. Accordingly, the genetic diversity of the isolates was calculated, and their kinship relations were determined by cluster analysis using the NTSYS software package. URP-6R had the highest marker index among the studied primers, followed by URP-1F, URP-4R, and URP-25F, implying their higher efficiency in discriminating between the isolates. The results showed that the URP marker could discriminate between isolates using macroscopic morphological characteristics, such as color and colony type, potential of pigment production in the culture medium, and colony growth rate. Furthermore, there was no significant relationship between the geographical distribution of the isolates and the band patterns generated by the primers except for a few cases. The results generally revealed that the URP marker was an efficient tool for determining the genetic diversity of T. harzianum

Genetic Diversity of <i>Trichoderma harzianum</i> Isolates in Sunflower Rhizosphere: The Application of the URP Molecular Marker

The genetic diversity of 77 Trichoderma harzianum isolates collected from sunflower rhizosphere soils in Urmia, Khoy, and Salmas in West Azerbaijan province, Iran, was evaluated by using the Universal Rice Primer (URP) molecular marker. The DNA band pattern of the isolates was developed using seven primers of this marker. These primers produced 186 gene loci, out of which 182 loci were polymorphic. Accordingly, the genetic diversity of the isolates was calculated, and their kinship relations were determined by cluster analysis using the NTSYS software package. URP-6R had the highest marker index among the studied primers, followed by URP-1F, URP-4R, and URP-25F, implying their higher efficiency in discriminating between the isolates. The results showed that the URP marker could discriminate between isolates using macroscopic morphological characteristics, such as color and colony type, potential of pigment production in the culture medium, and colony growth rate. Furthermore, there was no significant relationship between the geographical distribution of the isolates and the band patterns generated by the primers except for a few cases. The results generally revealed that the URP marker was an efficient tool for determining the genetic diversity of T. harzianum

Using Chromosomal Abnormalities and Germination Traits for the Assessment of Tritipyrum Amphiploid Lines under Seed-Aging and Germination Priming Treatments

Primary Trans Chromosomal Tritipyrum (PTCT) amphiploid is a new cereal grown in saline soil and brackish water for grain and forage production. We evaluated the tolerance to seed deterioration in 13 promising PTCT lines, assessing accelerated aging (AA) tests by using AA boxes with 100% relative humidity at 40 °C for 72 h. The (Ma/b)(Cr/b)F4 and (St/b)(Cr/b)F4) PTCT lines, more sensitive to seed aging, were primed with NaCl, Salicylic Acid (SA), and Polyethylene Glycol (PEG) to increase the seed vigor of artificially aged seeds. Germination and emergence traits, biochemical parameters, and chromosomal abnormalities induced by artificial aging were measured in deteriorated and not-deteriorated seeds. The highest reduction percentages related to seed vigor were observed in (Ka/b)(Cr/b)F2 (34.52) and La(4B,4D)/b (28.15) lines, while the lowest was found in (Ma/b)(Cr/b)F4 (7.65) and (St/b)(Cr/b)F4 (7.46) lines. Seed aging also increases electrolytes, potassium, and protein leakages. Chromosomal abnormalities are caused by seed aging that interferes with chromosome behaviors during cell division. Seed priming on aged seeds revealed an increase in the germination percentage (GP) with PEG treatment, while the priming by SA showed an increase in seedling traits, such as the seedling length (SL2). In conclusion, we highlighted the potential use of different PTCT lines and the effective use of seed priming on deteriorated seed to enhance seed viability and seedling vigor as a useful tool for sustainable agriculture

Is the Arbuscular Mycorrhizal Fungus <i>Funneliformis mosseae</i> a Suitable Agent to Control Criconematid Populations?

Several studies have shown the potential of using mycorrhizal fungi in increasing the plant yield by simultaneously reducing damages caused by pathogens. Plant parasitic nematodes (PPNs) are among the most feared pathogens for crops. This study aimed to evaluate the effects of Funneliformis mosseae as a mycorrhizal fungus on the population abundance of three world widespread species of nematodes from the family Criconematidae: Mesocriconema xenoplax, Mesocriconema antipolitanum, and Criconemides informis. Pure and highly abundant populations of each species were collected from Urmia city in Northwestern Iran, after the identification morphological and morphometric characteristics. The experiments were carried out in greenhouse conditions on three different rhizospheres of alfalfa, sugar beet, and wheat. After five months, the final population of nematodes and fungus, and the root surface on host plants inoculated and non-inoculated with the fungus F. mosseae, were evaluated. The results showed that the population of nematodes was increased in the presence of the fungus. It could be assumed that the extension of the host surface level of roots by the fungus resulted in more feeding sites for nematode activity and, consequently, higher population densities. In this study, the fungus did not seem to play a suitable role in controlling ectoparasitic nematode growth. However, since there are still many open questions about mycorrhizal fungi’s role in agriculture, more research should be conducted

Population Genetic Structure of Meloidogyne javanica Recovered from Different Regions of Iran

In a survey of root-knot nematodes in Iran, twenty-nine populations were collected from eleven provinces. All populations were identified as Meloidogyne javanica based on morphological and morphometric characteristics of females, males, J2s, and perineal patterns. Sequence Characterized Amplified Region (SCAR) primers confirmed the morphological studies, and all these populations produced a specific band in 670 bp using Fjav and Rjav primers. Genetic structure analyses using the combination of RAPD and ISSR markers revealed four different groups, which was in agreement with UPGMA cluster analyses. These four groups were related to four different geographic regions with a high geographic distance. The total estimated genetic diversity was 8%, which was a low value. Values of FST and Nm were 0.628 and 0.148, indicating that populations of these four regions were separated from each other; however, some gene flow between them could be attributed to human activities. Mantel test also revealed a negative correlation between genetic diversity and geographic distance

The Effect of Some Wild Grown Plant Extracts and Essential Oils on Pectobacterium betavasculorum: The Causative Agent of Bacterial Soft Rot and Vascular Wilt of Sugar Beet

The bacterial soft rot and vascular wilt of sugar beet are the major diseases of sugar crops globally induced by Pectobacterium&nbsp;betavasculorum and P. carotovorum subsp. carotovorum (Pcc). The control of this bacterial disease is a severe problem, and only a few copper-based chemical bactericides are available for this disease. Because of the limitations of chemicals to control plant bacterial pathogens, the essential oils and extracts have been considered one of the best alternative strategies for their control. In this study, twenty-seven essential oils and twenty-nine plant extracts were extracted and evaluated for their antibacterial activities against Pectobacterium betavasculorum isolate C3, using the agar diffusion method at 0.01%, 0.1%, and 100% (v/v). Pure Pimpinella anisum L. oil exhibited the most anti-bacterial activity among three different concentrations of essential oils and extracts, followed by Thymus vulgaris L. oil and Rosa multiflora Thunb. extract. The efficacy of effective essential oils and extracts on Ic1 cultivar of sugar beet seeds germination and seedling growth in vivo also were tested. The seed germination of the Ic1 cultivar was inhibited at all the concentrations of essential oils used. Only extracts of Rosa multiflora Thunb., Brassica oleracea L., Lactuca serriola L., Salvia rosmarinus Spenn., Syzygium aromaticum (L.) Merr. and L.M.Perry, Eucalyptus globulus Labill., and essential oils of Ocmium basilicum L., Pimpinella anisum L., and Mentha&times; piperita L.L. in 0.1% concentration had no inhibition on seed germination and could improve seedling growth. This is the first report of the antibacterial activity of essential oils and extracts on Pectobacterium betavasculorum

Safflower (<i>Carthamus tinctorius</i> L.) Response to Cadmium Stress: Morpho-Physiological Traits and Mineral Concentrations

Cadmium is a widely distributed heavy metal in agricultural soils that affects plant growth and productivity. In this context, the current study investigated the effects of different cadmium (Cd) doses (0, 25, 50, 75, and 100 mg L−1 of CdSO4) on the growth and physiological attributes of safflower (Carthamus tinctorius L.) including plant height (cm), root length (cm), fresh weight (g) of root, stem, and leaves, leaf number, macro and micro-nutrients, Se, and heavy metal (Cd, Cr, and Pb) content. The experiment was carried out in a completely randomized design (CRD) with four replicates. The results showed that Cd stress significantly negatively affected all growth indices, macro- and micro-nutrients, and heavy metal content. In addition, it increased the MDA and APX activities. The highest amounts of Fe, Mn, Ni, Pb, Zn, K, Na, Cd, Cr, and Cu were determined in plant roots, while the highest values of Ca and Mg were detected in plant stem tissues. High Cd doses decreased the content of Ca, K, Mg, Cr, Cu, Fe, Mn, Ni, Pb, Se, and Zn in safflower plant tissues by 45.47%, 39.33%, 79.28%, 68.21%, 37.06%, 66.67%, 45.62%, 50.38%, 54.37%, 33.33% and 65.87%, respectively, as compared to the control treatments