Transcriptome-based analysis of candidate gene markers associated with resistance mechanism to Phytophthora melonis that causes root and crown rot in pumpkin

Root and crown rot incited by an oomycete, Phytophthora melonis , causes significant yield losses in commercial pumpkin (Cucurbita pepo ) production worldwide. Currently, resistant cultivars and knowledge of molecular mechanism of C. pepo against P. melonis are scarce. Here, we analysed the quantitative gene expression changes of 10 candidate gene markers (bHLH87, ERF014, HSF, MYB, PR-1, WRKY21, CPI, POD, PSK, SGT ) in pumpkin roots and leaves at three time points (h post-inoculation, hpi) following inoculation with P. melonis in two resistant (Ghelyani and Tanbal), and two susceptible (Marmari and Khoreshti) varieties of pumpkin. Gene expression using quantitative real time PCR along a time course revealed the strongest transcriptomic response at 48 and 72hpi in resistant genotypes, 1.1-2.7-fold in roots and leaves, respectively, with a high significant correlation (r =0.857**-0.974**). We also found that CPI , PSK, SGT1 and POD act as a dual regulator that similarly modulate immunity not only against P. melonis , but also against other diseases such as early blight (Alternaria cucumerina) , powdery mildew (Podosphaera xanthii ), downy mildews (Pseudoperonospora cubensis ), and pathogenic plant nematodes (Meloidogyne javanica ). Furthermore, significantly higher activities of the ROS scavenging defence enzymes, catalase (1.6-fold increase) and peroxidase (6-fold increase) were observed in the roots of resistant cultivars at different hpi compared with non-inoculated controls. In addition, the biomass growth parameters including leaf and root length, stem and root diameter, root fresh weight and volume were significantly different among studied genotypes. Cumulatively, the transcriptome data provide novel insights into the response of pumpkins for improving pumpkin breeding to P. melonis .

Corrigendum to: Assessing genetic diversity and population structure of Iranian melons (Cucumis melo) collection using primer pair markers in association with resistance to Fusarium wilt

We evaluated genetic diversity and population structure of Iranian melons (Cucumis melo L.) using combinations of 35 primer pairs: 15 Simple-Sequence-Repeats (SSR); 10 Inter-Simple-Sequence-Repeats (ISSR); and 10 Sequence-related amplified polymorphism (SRAP) markers in association with resistance to melon Fusarium wilt, caused by Fusarium oxysporum f. sp. melonis (FOM ). Genetic similarity was determined by simple matching coefficient (SSM) and dendrogram by clustering-analysis with unweighted pair groups using arithmetic averages (UPGMA). By combining ISSR-SSR-SRAP markers, a high degree of variation among the melons was detected. The mean polymorphism information content (PIC), marker index (MI), effective-number of alleles (I), expected heterozygosity (H), and Nei's gene diversity parameters were 0.392, 0.979, 1.350, 0.551 and 0.225, respectively. According to MI, PIC, I, H, and Nei indices evaluation, ISSR6, ISSR9, SRAP3, SRAP5, SSR3 and SSR6 had the best performance in genetic diversity of the related melons population. The 35 primers yielded a total of 264 bands, of which 142 showed polymorphism. Clustering of genotypes based on resistance to Fusarium wilt, and comparison with grouping on SSR, SRAP and ISSR marker revealed a significant compliance between disease severity and molecular marker dendrograms. Thus, increasing the number of molecular markers for genetic diversity provides a powerful tool for future agricultural and conservation tasks.

Assessing genetic diversity and population structure of Iranian melons (Cucumis melo) collection using primer pair markers in association with resistance to Fusarium wilt

We evaluated genetic diversity and population structure of Iranian melons (Cucumis melo L.) using combinations of 35 primer pairs: 15 Simple-Sequence-Repeats (SSR); 10 Inter-Simple-Sequence-Repeats (ISSR); and 10 Sequence-related amplified polymorphism (SRAP) markers in association with resistance to melon Fusarium wilt, caused by Fusarium oxysporum f. sp. melonis (FOM ). Genetic similarity was determined by simple matching coefficient (SSM) and dendrogram by clustering-analysis with unweighted pair groups using arithmetic averages (UPGMA). By combining ISSR-SSR-SRAP markers, a high degree of variation among the melons was detected. The mean polymorphism information content (PIC), marker index (MI), effective-number of alleles (I), expected heterozygosity (H), and Nei's gene diversity parameters were 0.392, 0.979, 1.350, 0.551 and 0.225, respectively. According to MI, PIC, I, H, and Nei indices evaluation, ISSR6, ISSR9, SRAP3, SRAP5, SSR3 and SSR6 had the best performance in genetic diversity of the related melons population. The 35 primers yielded a total of 264 bands, of which 142 showed polymorphism. Clustering of genotypes based on resistance to Fusarium wilt, and comparison with grouping on SSR, SRAP and ISSR marker revealed a significant compliance between disease severity and molecular marker dendrograms. Thus, increasing the number of molecular markers for genetic diversity provides a powerful tool for future agricultural and conservation tasks.

Transcriptome-based analysis of resistance mechanisms to Bipolaris sorokiniana, a common wheat root-rot disease

In common root and crown rot (CRR), Bipolaris sorokiniana (Sace.) is one of the important in wheat, causing considerable yield losses globally. Sources of resistance can provide a feasible and effective method of control for plant disease management. However, knowledge on mechanisms of resistance is scarce. We screened 33 wheat genotypes against B. sorokiniana under greenhouse and field conditions. In addition, real-time quantitative PCR (qPCR) analysis using ten novel candidate gene markers, Cre3, EDS1, LTP5, PGIP, PR-1, PIEP1, TLP, UGT, Stb6 and PFT, was conducted on leaves and roots, along with changes in activity of antioxidant enzymes, peroxidase, catalase, β-1,3-glucanase, and phenolic content for their involvement in disease impact mechanisms. Lowest disease severity was in 'Alvand', followed by 'Baharan' and 'Bam' as resistant genotypes. Quantitative gene expression showed that, although the candidate defence genes were upregulated 1.24- to 3.5-fold in wheat roots and leaves inoculated with B. sorokiniana, they were highly regulated in resistant varieties 'Alvand', 'Mehregan' and 'Bam'. Cre3, a resistance gene to cereal cyst nematode Heterodera filipjevi, was regulated in cultivars resistant to B. sorokiniana. Similar results were obtained for Stb6, a gene resistant to Septoria tritici blotch, EDS1 resistant to powdery mildew, Blumeria graminis, and the genes PR-1 and UGT resistant to leaf rust, Puccinia triticina. Antioxidant enzyme activity also showed the highest increases in resistant genotypes. In conclusion, the T. aestivum-B. sorokiniana interaction in resistant wheat cultivars uses defence-related genes and enzymes that protect wheat towards sustainable development. Further such studies will shed light on simultaneous resistance to other diseases in wheat cultivars.

Biochemical defense mechanism associated with host-specific disease resistance pathways against Rhizoctonia solani AG3-PT potatoes canker disease

Screening for resistance in 40 potato genotypes to Rhizoctonia solani AG-3PT-stem-canker, antioxidant enzymes activity as well as total phenol compounds were documented. Rhizoctonia solani AG-3PT-stem-canker is one of the most devastating diseases that leads to severe economic losses in potatoes, Solanum tuberosum globally. Crop management and eugenic practices, especially the use of resistance can be effective in reducing the disease incidence. However, the information about potato-R. Solani interaction is still limited. This study explored screening for resistance in forty potato genotypes to R. solani, analyzing biomass growth parameters (BGPs), as well as antioxidant enzymes activity of which peroxidase/peroxide-reductases (POXs), superoxide dismutase (SOD), polyphenol oxidase (PPO), catalase (CAT), phenylalanine ammonia-lyase (PAL), β-1,3-glucanase (GLU) and total phenol compounds (TPCs) were taken into account. In addition, we analyzed up-regulation of two gene markers (PR-1 and Osmotin), using reverse transcription quantitative PCR (RT-qPCR). For which, the resistant 'Savalan', partially resistant 'Agria', partially susceptible 'Sagita' and susceptible 'Pashandi' were selected to explore the trails in their roots and leaves over the time courses of 1, 2 and 3-weeks post inoculation (wpi) following inoculation. Cluster analysis divided potatoes into four distinct groups, based on disease severity scales (0-100%) significance. The BGPs, shoot and root length, fresh and dry weight, and root volume were also significantly higher in infected potatoes compared to non-inoculated controls. Antioxidant enzymes activity also indicated the highest increased levels for POX (fourfold at 3wpi), CAT (1.5-fold at 3wpi), SOD (6.8-fold at 1wpi), and PAL (2.7-fold at 3wpi) in the resistant genotype, 'Savalan', whereas the highest activity was recorded in TPC (twofold at 1 wpi), PPO (threefold at 3wpi), and GLU (2.3-fold at 1wpi) in partially resistant genotypes. Although the defense-related enzymatic activities were sharply elevated in the resistant and partially resistant genotypes following inoculation, no significant correlations were between the activity trends of the related enzymes. The two related gene markers also showed comprehensive transcriptional responses up to 3.4-fold, predominantly in resistant genotypes. Surprisingly, the PR-1 gene marker, basically resistant to Wilting agent Verticillium dahlia was overexpressed in resistant 'Savalan' and 'Agria' against R. solani AG3-PT. Similar results were obtained on Osmotin gene marker resistant to late-blight P. infestans, and early-blight Alternaria solani that similarly modulates immunity against R. solani. Furthermore, there was a significant correlation between resistance, enzyme activity, and gene expression in the aforesaid cultivars. Studying the physiological metabolic pathways of antioxidant enzymes activity appears to be an important direction in research to elucidate resistance to R. solani in potatoes.

Genomic markers analysis associated with resistance to Alternaria alternata (fr.) keissler-tomato pathotype, Solanum lycopersicum L

Alternaria alternata, the causal pathogen of early blight (EB) disease, is one of the most important diseases in tomato, and other solanaceae family. We analyzed 35 tomato genotypes for quantitative/qualitative traits and biomass growth parameters, as well as the extent and structure of genetic variation associated with EB resistance. Phenotypic comparisons displayed significant differences in leaf blade width (24.95%), stem thickness (30.28%), foliage density (18.88%), and plant size (18.89%), with significant positive correlations with EB resistance (0.18-0.75). Correlation analysis showed that mature fruit size, thickness of fruit pericarp, and leaf type were significantly and negatively correlated with EB resistance (up to -0.41). The susceptible tomato seedlings represented significant reductions in biomass parameters. According to ISSR analysis, the highest resolving power (≥0.79) and heterozygosity (≥0.24) values revealed the presence of high genetic variability among the tomato genotypes. Bayesian model-based STRUCTURE analysis assembled the genotypes into 4 (best ΔK = 4) genetic groups. Combined phenotypic and molecular markers proved to be significantly useful for genetic diversity assessment associated with EB disease resistance.

Identification of novel associations of candidate genes with resistance to Rhizoctonia solani AG-3PT in Solanum tuberosum stem canker

To develop an understanding mechanism to define responding of potatoes to R. solani, we analyzed the expression of ten novel candidate gene-markers using reverse-transcription-quantitative PCR (RT-qPCR) in resistant 'Savalan' and partially resistant 'Agria' in contrast to susceptible 'Sagita', and partially susceptible 'Pashandi'. In addition, oxidant-enzymatic-activity of catalase and superoxide-dismutase, as well as biomass-growth-parameters; shoot and root length, fresh and dry weight, and root volume were considered as complementary factors to the involving mechanism accordingly. Gene-markers up-regulated maximum up to 3.5-fold with the highest correlation, r = 0.939** following R. solani-inoculation, predominantly in resistant genotypes. Surprisingly, WRKY8-gene, basically resistant to late-blight-Phytophtora infestans was also up-regulated to 2.3-fold in resistant 'Savalan' followed by 'Agria'. Similar results with 3.1-fold were obtained on Osmotin-gene resistant to early-blight-Alternaria alternata. Enzymatic-activity of catalase with 1.6-fold and superoxide-dismutase, 6.8-fold also showed the highest level of activity in resistant genotypes, and had a high significant correlation, r = 773** and r = 0.881** with expression levels of related gene-markers respectively. Similarly, there were significant differences in biomass-growth-parameters, but with reductions in partially susceptible 'Sagita' and susceptible 'Pashandi'. Conclusively, S. tuberosum-R. solani interaction revealed that certain gene-markers can cover resistance to more than one disease simultaneously.

Genetic diversity and biochemical analysis of Capsicum annuum (Bell pepper) in response to root and basal rot disease, Phytophthora capsici

This study analyzed the genetic variability and biochemical characteristics of edible and ornamental accessions of pepper, Capsicum annuum, in response to root and basal rot disease (RCR), caused by Phytophthora capsici, using resistance screening and genetic variability via Inter Simple Sequence Repeat marker (ISSR), bio-mass parameters, and enzymatic activity of Peroxidase or peroxide reductases (POX), Superoxide dismutase (SOD), Polyphenol oxidase (PPOs), Catalase (CAT), Phenylalanine ammonia-lyase (PAL), β-1,3-glucanase and phenolic content. The resistance in C. annuum '37ChilPPaleo', '19OrnP-PBI' and '23CherryPOrsh' and susceptibility in '2BP-PBI', '24BP-301' and '26BPRStarlet' accessions were confirmed. Nineteen out of 21 ISSR primers generated 185 polymorphic bands with a mean percentage band of 98.5 %, and an average number of bands of 9.9 per primer. Biomass parameters were significantly higher in resistant genotypes than the susceptible ones and non-inoculated controls. All the seven candidate enzymes were highly up-regulated in the resistant C. annuum accessions '19OrnP-PBI', '37ChillP-Paleo' and '23CherryP-Orsh' inoculated with P. capsici The mean level of enzyme activity varied from 1.5 to 5.6-fold higher in the resistant C. annuum, of which SOD was increased by 5.6 fold, followed by PAL 4.40 and PPO 3.75 fold in comparison to susceptible and non-inoculated controls. Overall, there was no significant correlation between resistance and genetic variability, and also between genetic variability and enzyme activity levels. However, there was a highly significant correlation between the resistance, bio-mass parameters and enzyme activity levels.

Periodic mesoporous organosilica with ionic-liquid framework supported manganese: an efficient and recyclable nanocatalyst for the unsymmetric Hantzsch reaction

We have described the catalytic application of a manganese containing ionic liquid-based ordered mesoporous organosilica in the synthesis of polyhydroquinolines.

Quality of life, religious attitude and cancer coping in a sample of Iranian patients with cancer

BACKGROUND

Cancer is one of the leading causes of mortality and morbidity worldwide. The incidence of cancer has increased markedly in recent decades in most countries. Studies have shown that diseases such as cancer affect the individuals' quality of life.

METHODS

The sample of study consisted of 384 patients selected through non-random convenient sampling procedure from three general hospitals and outpatient clinics in Isfahan and Tehran. The measures used in the study included a demographic questionnaire, the Iranian version of the European Organization for Research and Treatment of Cancer Quality of Life Questionnaire (EORTC QLQ-C30), the Cancer Coping Questionnaire, and the Religious Attitude Questionnaire.

RESULTS

The results revealed significant correlation between patients' scores on the total scale of the Cancer Coping Questionnaire and their scores on the Global health status/Quality of Life. Significant correlations were also found between patients' scores on the Religious Attitude Questionnaire and various scales of the Quality of Life Questionnaire. However, no significant correlations were found between Cancer Coping and Religious Attitude measures in any type of cancer except for the prostate cancer.

CONCLUSIONS

Religious attitude was a significant and important factor in coping with cancer. In addition, patients' quality of life correlated significantly with religious attitude as well as cancer coping measures. However, the results did not show any significant relationship between religious attitude and cancer coping measures except in patients with prostate cancer. The findings of this study are consistent with other studies that have shown significant correlations between religiosity and spirituality and quality of life in patients with life threatening diseases.

The effect of iron and iron chelators on the in-vitro block to development of the mouse preimplantation embryo: BAT6 a new medium for improved culture of mouse embryos in vitro

The effect of iron and iron chelators on the development of the mouse embryo in vitro from the 1-cell stage to the blastocyst has been investigated. An adverse effect of iron was found. The high affinity iron chelator, desferal, also blocked development, whilst transferrin (whether as apoprotein or saturated with iron), DETAPAC and EDTA promoted development. The addition of transferrin permitted development to the blastocyst stage of embryos from stains normally exhibiting the 2-cell block. Under such circumstances both the rate of embryonic development and the proportion of embryos reaching the blastocyst stage approached levels found in vivo. Based on these results, a new medium, BAT6, is described for the optimal in-vitro culture of mouse embryos.