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The plant-growth-promoting rhizobacteria (PGPR) in the rhizosphere affect plant growth, health, and productivity, as well as soil-nutrient contents. They are considered a green and eco-friendly technology that will reduce chemical-fertilizer usage, thereby reducing production costs and protecting the environment. Out of 58 bacterial strains isolated in Qassim, Saudi Arabia, four strains were identified by the 16S rRNA as the Streptomyces cinereoruber strain P6-4, Priestia megaterium strain P12, Rossellomorea aquimaris strain P22-2, and Pseudomonas plecoglossicida strain P24. The plant-growth-promoting (PGP) features of the identified bacteria involving inorganic phosphate (P) solubilization, the production of indole acetic acid (IAA), and siderophore secretion were assessed in vitro. Regarding the P solubilization, the previous strains' efficacy reached 37.71%, 52.84%, 94.31%, and 64.20%, respectively. The strains produced considerable amounts of IAA (69.82, 251.70, 236.57, and 101.94 µg/mL) after 4 days of incubation at 30 °C. Furthermore, the rates of siderophore production reached 35.51, 26.37, 26.37, and 23.84 psu, respectively, in the same strains. The application of the selected strains in the presence of rock phosphate (RP) with tomato plants under greenhouse conditions was evaluated. The plant growth and P-uptake traits positively and significantly increased in response to all the bacterial treatments, except for some traits, such as plant height, number of leaves, and leaf DM at 21 DAT, compared to the negative control (rock phosphate, T2). Notably, the P. megaterium strain P12 (T4), followed by R. aquimaris strain P22-2 (T5), revealed the best values related to plant height (at 45 DAT), number of leaves per plant (at 45 DAT), root length, leaf area, leaf-P uptake, stem P uptake, and total plant P uptake compared to the rock phosphate. The first two components of the PCA (principal component analysis) represented 71.99% (PCA1 = 50.81% and PCA2 = 21.18%) of the variation at 45 DAT. Finally, the PGPR improved the vegetative-growth traits of the tomato plants through P solubilization, IAA, and siderophore production, and ameliorated the availability of nutrients. Thus, applying in PGPR in sustainable agriculture will potentially reduce production costs and protect the environment from contamination by chemical fertilizers and pesticides. [ABSTRACT FROM AUTHOR]

Purpose: BRCA gene mutations (BRCAm) have an impact on patients' characteristics and clinical outcomes of ovarian cancer (OC). The frequency and patterns of BRCAm vary among countries and ethnicities. There are limited data from Saudi Arabia (SA); thus, this study aims to determine the frequency, pattern, and impact on patient characteristics and outcomes of BRCAm OC compared to wild-type BRCA (BRCAw) in Saudi women.Methods: This retrospective study evaluated women diagnosed with non-mucinous OC, fallopian tube, or peritoneal carcinoma who had BRCA status tested in an accredited lab between January 2016 and December 2017. The associations between various parameters and BRCAm were estimated using logistic regression. Statistical analysis performed with SPSS (Version 27).Result: Sixty-one women with a median age of 52 at diagnosis were analyzed. Germline BRCA mutations were found in 41% of cases (25/61). The most common deleterious germline BRCA1 mutation was c.1140dupG (39%). Most women (72%) had no family history of cancers and 82% had advanced stage. Regardless of BRCA mutations, an optimal overall response rate (ORR) to first-line treatment has been achieved although most cases relapsed (84%) and the majority were platinum-sensitive relapse (85%). Higher ORR to subsequent lines and better survival were obtained in women with BRCA-mutation.Conclusion: The prevalence of BRCAm of OC was higher in Saudi women compared to regional and most of the international figures. The better clinical outcomes of BRCAm women agreed with the reported evidence. Further studies on BRCA mutations of OC and genetic counseling are highly recommended.Trial Registration: Trial approved by the Institutional Review Board of King Faisal Specialist Hospital and Research Center (RAC # 2171137) and conducted at King Faisal Specialist Hospital and Research Center, PO Box 3354, Riyadh 11,211, Saudi Arabia. [ABSTRACT FROM AUTHOR]

Introduction: Human epidermal growth factor receptor 2 (HER-2) targeted therapy regimens can improve tumor response in HER-2-positive metastatic breast cancer (MBC), with overall survival benefits. Objective: We evaluated the efficacy of dual HER-2 blockade combined with chemotherapy for HER-2-positive MBC patients as a first-line therapy in our patient population. Patients and Methods: We identified 75 patients at King Faisal Specialist Hospital and Research Center that received trastuzumab, pertuzumab, and docetaxel as a first-line therapy in HER-2 positive MBC in 2013–2016. Results: Median age at diagnosis was 45 years; 54.7% were estrogen receptor (ER)-positive. 10% of patients presented with only bone metastasis. The median follow-up time was 36 months with an objective response rate of 74.7% (complete response [CR] 18.7%; partial response [PR] 56%). The 5-year progression-free survival (PFS) and overall survival (OS) were 21% and 71.9% respectively, with a median PFS of 36 months (95% confidence interval [CI] 23.6–48.4). The 5-year OS for ER-negative and ER-positive patients was 93.9% and 59.4% respectively (p = 0.189); 23 patients experienced grade 1/2 toxicity and 2 patients had grade 3/4 toxicity. In terms of OS and PFS, the site of metastasis did not make any significant difference. Conclusions: First line pertuzumab, trastuzumab, and docetaxel for HER-2-positive MBC patients was found to be an effective and safe therapy in the Saudi population. This finding was consistent with the results seen in the CLEOPATRA trials. [ABSTRACT FROM AUTHOR]

From 2015 to 2017 symptoms associated with phytoplasmas were observed in vegetable crop farms located in Uyun AlJiwa and Al-Dawadmi, cities located in the Al-Qassim Region and the Riyadh Province, respectively. Affected eggplants exhibited symptoms of phyllody, little leaves and witches broom, symptomatic cabbage showed multiple heads, beetroot showed reddening, stunting and leaves proliferation symptoms, while celery plants showed stunting and yellowing symptoms. To determine if the symptomatic samples were affected by phytoplasmas, PCR was performed with phytoplasma universal primers P1/P7 followed by a nested PCR with primer pair R16mF2/R16mR2, which target the 16S rRNA-encoding gene locus. PCR revealed that 20/20 symptomatic eggplants, 15/20 symptomatic cabbage, 26/30 symptomatic beetroot, and 9/11 symptomatic celery plants were infected with phytoplasma, and sequencing of the amplified genes revealed that the phytoplasmas belonged to the peanut witches'-broom group (16SrII). Sequence analysis using in silico restriction fragment length polymorphism (RFLP) and phylogenetic analysis revealed the presence of two closely related but distinct sequences from the 16SrII-D and the recently described 16SrII-X subgroups. The two sequences differed by a single base pair and both subgroups were detected in cabbage, beetroot, and celery, while eggplant was only affected by subgroup 16SrII-X. Sequence analysis of the chaperonin-60 universal target confirmed the classification of these phytoplasma strains in the 16SrII group and their close phylogenetic relationship. This is the first report of eggplant, cabbage, beetroot, and celery affected by phytoplasma in Saudi Arabia, and the first report of these plant hosts affected by the 16SrII-X subgroup. • This is the first report of eggplant, cabbage, beetroot, and celery affected by phytoplasma in Saudi Arabia. • Molecular identification of 'Ca. Phytoplasma australasia'-related strains based on 16Sr RNA operon and cpn60 UT sequence analysis. • Expansion of plant hosts affected by the 16SrII-X subgroup in Saudi Arabia. [ABSTRACT FROM AUTHOR]

Severe terminal bud rot disease symptoms of Washingtonia, Washingtonia robusta, palms were observed in the 5-year-old trees in a farm located at the north of Al Shehia governorate, Qassim region, Saudi Arabia. The fungus found associated with the diseased palm buds was isolated in the laboratory, and pathogenicity tests were conducted on healthy 1-year-old Washingtonia palms, at an experimental station, Agriculture and Veterinary Medicine. Pathogenicity tests showed that a single fungus caused typical symptoms of bud rot on the inoculated trees. Petiole bases and terminal buds were rotted after 5-6 weeks of inoculation. The pathogen was identified through microscopy and characterized molecularly, using internal transcribed spacer (ITS) regions of ribosomal DNA, as a fungal-like organism Phytophthora nicotianae (synonym = P. parasitica). Experiments were conducted on the biological control of the pathogen in the laboratory, and a promising RN13 isolate of Lysobacter enzymogenes was selected for further study. This study seems to be the first report of bud rot disease of Washingtonian palms caused by P. nicotianae in Saudi Arabia. Great attention should be given to this disease because it is soil borne and may be transmitted to the date palm crop. [ABSTRACT FROM AUTHOR]

Triazole fungicides may potentially harm human health. The 'quick, easy, cheap, effective, rugged, and safe' approach has become popular for extraction and cleanup during pesticide residue analysis. We aimed to (a) validate a method for the simultaneous determination of myclobutanil, penconazole, tebuconazole, and triadimenol in squash using LC-MS/MS and (b) determine the pre-harvest intervals (PHIs) and assess the related risk of consuming squash cultivated under open-field conditions in Saudi Arabia. Using acetonitrile as the extraction solvent and fourfold dilution in deionized water led to weak signal suppression (<-6.1%). The limits of quantitation ranged from 10 to 40 μg/kg. Mean recovery and relative standard deviation ranged from 81.7 to 96.3% and from 3.6 to 11.4%. The half-lives ranged from 2.22 to 3.83 days, and the dissipation followed first-order kinetics. The terminal residues of myclobutanil, penconazole, tebuconazole, and triadimenol were <0.771, <0.307, <0.459, and <0.954 mg/kg, respectively, 7 days after two or three applications of recommended dosages. The PHIs of 7.1-11.4, 8.7-13.1, 3.8-5.3, and 11.3-14.3 days are suggested after the application of the recommended dose and double the recommended dose. A consumer risk assessment based on estimated dietary intake indicated that the consumption of squash treated with the recommended doses does not pose a significant health risk., (© 2021 John Wiley & Sons, Ltd.)