bluuebunny/crossref_metadata_2025 huggingface dataset:
Genome-wide association mapping for agronomic and quality traits in foxtail millet
Authors: Lou Yanhong , Chen Yun , Liu Zhihao , Sun Mingjie , Han Fei , Wang Tingting , Wang Hui , Zhuge Yuping , Chen Liang
Published: June 2019

Background: Foxtail millet [Setaria italica (L.) P. Beauv.] is a particularly important cereal and fodder crop in arid and semi-arid regions. The genomic variation and alleles underpinning agronomic and quality traits are important for foxtail millet improvement. To better understand the diversity of foxtail millet and facilitate the genetic dissection of its agronomic and quality traits, we used high-quality single nucleotide polymorphisms (SNPs) to perform a genome-wide association study (GWAS). Results: Using genotyping-by-sequencing, 107 foxtail millet accessions were sequenced, and further analysis revealed 72,181 high-quality SNPs, of which 53 were significantly associated with 15 agronomic and quality traits. These SNPs were distributed across the nine chromosomes of foxtail millet; 44 were located in intergenic regions, whereas one and eight SNPs were located in exon and intron regions, respectively. The GWAS revealed that 28 SNPs were associated with a single trait. Conclusions: For some of the significant SNPs, favourable genotypes showed pyramiding effects for several traits. The 53 loci identified in this study will therefore be useful for breeding programs aimed at foxtail millet improvement.
The Relationship between Teaching Quality and Academic Engagement in Medical Students: a descriptive-correlational study
Authors: Bayat Amir-Hossein , Haghgoo Amin , Asady Hadi , Gholamhosseini Elahe , Armoon Bahram
Published: June 2019

Background: One of the essential activities in improving the quality and effectiveness of teaching is to pay attention to the quality of teaching and engagement of students in their academic process. Thus, the aim of this study was to determine the relationship between teaching quality and academic engagement among Iranian nursing students. Methods: This is a descriptive-correlational study. The present study was carried out on 124 anesthesia and operating room nursing students who were selected using simple random sampling in the year 2017. The research tools included standard demographic, course experience, and academic engagement questionnaires. Data analysis was carried out using descriptive tests, independent t-test, and Pearson correlation in SPSS ver. 24. Results: The results of Pearson correlation analysis on the relationship between the subscales of teaching quality, including good teaching, clear goals, appropriate assessment, appropriate workload, independence, and generic skills with academic engagement showed a statistically significant relationship between all remaining subscales, except for the proper workload sub-scale (P=0.234). Conclusion: The results of this study showed a significant positive correlation between the course experience and academic engagement. Therefore, steps can be taken to improve the quality of the educational system using active and student-centered teaching methods.
Young Adult Stroke in Taiwan: etiologies and outcomes
Authors: Chen Chun-Yu , Lin Po-Tso , Syu Ruei-Wun , Hsu Shao-lun , Chang Li-Hsin , Tsai Jui-Yao , Huang Hui-Chi , Liu Tzu-Ching , Wang Yun-Huei , Lin Chun-Jen , Tang Chih-Wei , Hsu Li-Chi , Chung Chih-Ping , Liu Hung-Yu , Chi Nai-Fang , Lee I-Hui
Published: June 2019

Background

Early-onset adult stroke has not been fully characterized in Asians.

Objectives

We investigated the etiologic subtypes, risk factors and 1-year outcomes of early-onset stroke (16 – 55 years of age) in a Taiwanese cohort.

Methods

We retrospectively reviewed consecutive patients with acute stroke admitted to the Taipei Veterans General Hospital in Taiwan between 2009 and 2017. Patients were classified by age of onset (≤ or > 55) and etiologic subtypes and regularly followed for 1 year.

Results

Among all stroke patients (n=8155), 17.6% (n=1310) were early-onset, who had slightly more spontaneous hemorrhagic stroke (50.8%) than ischemic stroke (49.2%). The most common etiologic subtypes of hemorrhagic stroke were hypertensive intracerebral hemorrhage (ICH), subarachnoid hemorrhage and undetermined ICH. The most common subtypes of infarction were large artery atherosclerosis, other determined diseases (52.5% arterial dissection) and embolic stroke of undetermined source. Smoking, alcohol overdrink, obesity, ischemic heart disease and family history of stroke were more in the early-onset than the elderly patients. The early-onset patients with familial stroke (n=87, 6.6%) were more males and more commonly had infarction than those without familial stroke. Monogenic diseases accounted for 5.7% of young familial stroke. At 1-year follow-up, the early-onset patients with infarction displayed greater functional improvements but more stroke recurrence than those with ICH.

Conclusions

Hypertensive hemorrhagic stroke and large artery atherosclerosis or dissection occlusion are characteristically common etiologies of young stroke in Taiwan. Early-onset infarction had higher recurrence yet better 1-year outcomes than early-onset ICH. Patients with familial versus non-familial aggregation had more ischemic infarction and monogenic diseases.
Assessing utility of clinical exome sequencing in diagnosis of rare idiopathic neurodevelopmental disorders in Indian population
Authors: Sheth Harsh , Pancholi Dhairya , Bhavsar Riddhi , Mannan Ashraf U. , Ganapathy Aparna , Chaudhari Mayank , Shah Sudhir , Solanki Dhaval , Sheth Frenny , Sheth Jayesh
Published: June 2019

Background: Neurological diseases are phenotypically and genotypically heterogeneous. Clinical exome sequencing (CES) has been shown to provide a high diagnostic yield for these disorders in the European population but remains to be demonstrated for the Indian population.

Methods: A cohort of 19 idiopathic patients with neurological phenotypes, primarily intellectual disability and developmental delay, were recruited. CES covering 4620 genes was performed on all patients. Candidate variants were validated by Sanger sequencing.

Results: CES in 19 patients provided identified 21 variants across 16 genes which have been associated with different neurological disorders. Fifteen variants were reported previously and 6 variants were novel to our study. Eleven patients were diagnosed with autosomal dominant de novo variants, 7 with autosomal recessive and 1 with X-linked recessive variants. CES provided definitive diagnosis to 10 patients, hence the diagnostic yield was 53%.

Conclusion: Our study suggests that the diagnostic yield of CES in the Indian population is comparable to that reported in the European population. CES together with deep phenotyping could be a cost-effective way of diagnosing rare neurological disorders in the Indian population.
Virulence analysis of 81 of Pseudomonas aeruginosa genomes available in public sequence databases
Authors: Brzozowski Marcin , Jursa-Kulesza Joanna Barbara , Kosik-Bogacka Danuta
Published: June 2019

Background

Pseudomonas aeruginosa is a pathogen capable of causing a wide range of severe opportunistic infections. Its genome contains numerous virulence genes encoding secretion systems of different types, structures responsible for adhesion and motility, toxins, proteases, siderophores, and others. The aim of this study is to analyse virulence, population structure, and distribution of highly divergent genes among 81 P. aeruginosa strains available in whole genome sequence databases.

Results

For this purpose, 260 virulence genes were searched in 81 different P. aeruginosa whole genomes that were available in databases. We identified most of the virulence genes as core and softcore genes. The most of the highly divergent sequences encoding pyoverdines, flagella and pilA were acknowledged as accessory, because of the differences in sequence among different alleles of those genes. Phylogenetic tree revealed the existence of three genetic groups of P. aeruginosa. Strains of the first clade were characterised as ExoS positive, whiles genomes of the second clade were ExoU positive. The member of third clade, PA7 strain was the only strain deprived of all T3SS genes. The analysis of pyoverdine locus facilitated finding a new pyoverdine type similar to pyoverdine type III. This newly described variant was present in 7 different strains. It contained a gene that was probably created by the fusion of pilD and pilI genes. In order to determine the coexistence of genes encoding exoenzymes, flagella and pyoverdines, Pearson correlation coefficients were calculated. There were significant correlations between genes encoding ExoS/ExoU-type strains and genes encoding type-A/type-B flagella. The correlation also occurred between

Conclusion

This study facilitates describing genetic differences of various P. aeruginosa strains based on Pseudomonas aeruginosa whole genome information from online databases. We conclude that most P. aeruginosa virulence genes are present in more than 95% of available genomes of the species. There are correlations of occurrence of different P. aeruginosa accessory virulence genes.
Recurrent Risk of Ischemic Stroke due to Vertebrobasilar Dolichoectasia
Authors: Chen Zhaoyao , Zhang Shuai , Dai Zhengze , Cheng Xi , Wu Minghua , Dai Qiliang , Liu Xinfeng , Xu Gelin
Published: June 2019

Background: Patients with vertebrobasilar dolichoectasia usually have persistent hemodynamic abnormalities, and therefore, may bear an increased risk of stroke. This study aimed to identify risk factors for stroke recurrence in patients with vertebrobasilar dolichoectasia.

Methods: Patients with acute ischemic stroke were screened and evaluated for eligibility. Enrolled patients were followed via scheduled clinical visits or telephone interviews. Ischemic stroke recurrence was proposed with clinical symptoms and confirmed with cranial Magnetic Resonance Imaging or Computerized Tomography scans. Baseline characteristics and vascular geometry were compared between patients with and without stroke recurrence. Significant parameters were introduced into COX proportional hazard model to detect possible predictors of stroke recurrence.

Results: A total of 115 stroke patients with vertebrobasilar dolichoectasia were enrolled, of which 22 (19.1%) had recurrence during 22 ± 6 months follow-up. Basilar artery diameter ≥ 5.3mm (HR = 4.744; 95% CI, 1.718-13.097; P = 0.003), diffuse intracranial dolichoectasia (HR = 3.603; 95% CI, 1.367-9.496; P = 0.010) and ischemic heart disease history (HR = 4.095; 95% CI, 1.221-13.740; P = 0.022) had increased risk of recurrence.

Conclusions: Stroke patients with vertebrobasilar dolichoectasia may have a high risk of recurrence. Larger basilar artery diameter or diffuse intracranial dolichoectasia may increase the risk of recurrence.
Premedication with dexmedetomidine to reduce emergence agitation: a randomized controlled trial
Authors: Kim Jong Chan , Kim Jihee , Kwak Hayeon , Ahn So Woon
Published: June 2019

Background: Nasal bone fracture is the most common type of facial fracture, and the high incidence of severe emergence agitation occurring after closed reduction of the nasal bone fracture can be challenging to manage. The purpose of this trial was to evaluate whether pre-operative administration of dexmedetomidine is effective in reducing the incidence and severity of emergence agitation in adults undergoing closed reduction of nasal bone fractures.
Methods: In this randomized controlled trial, 90 patients who were scheduled to undergo closed reduction of a nasal bone fracture were prospectively included and were randomly assigned to either the control group (n = 45; 0.9% saline infusion) or the dexmedetomidine group (n = 45; 1 mcg/kg over 10 minutes, pre-operatively). The primary endpoint was Aono's four-point scale after anesthesia. The recovery time and numeric rating scale score were assessed as secondary endpoints.
Results: Aono's four-point scale scores were lower in the dexmedetomidine group than in the control group (median: 1 [1-1] vs. 1 [1-2], 95% comfidence interval of difference: 0.01 to 0.02, P = 0.02). The number, severity, and duration of agitation episodes were significantly lower in the dexmedetomidine group than in the control group. Furthermore, the number of patients exhibiting intraoperative movement was lower in the dexmedetomidine group.
Conclusions: Pre-operative administration of dexmedetomidine demonstrated several significant benefits, such as a lower incidence of emergence agitation, reduced agitation severity, and a shorter duration of agitation. Additionally, we observed more stable maintenance of intraoperative anesthesia with less movement during the surgery.
Prednisolone versus placebo addition in the treatment of patients with recent-onset psychotic disorder: A trial design
Authors: Nasib Lyliana G. , Sommer Iris E. , Rossum Inge Winter-van , de Vries Jacqueline , Gangadin Shiral S. , Oomen Priscilla P. , Judge Gurmeet , Blom Renske E. , Luykx Jurjen J. , Beveren Nico J.M. van , Veen Natalie D. , Kroken Rune A. , Kahn René S. , Johnsen Erik
Published: June 2019

Background: The symptom severity of a substantial group of schizophrenia patients (30-40%) does not improve through pharmacotherapy with antipsychotic medication, indicating a clear need for new treatment options to improve schizophrenia outcome. Meta-analyses, genetic studies, randomized controlled trials and post-mortem studies suggest that immune dysregulation plays a role in the pathophysiology of schizophrenia. Some anti-inflammatory drugs have shown beneficial effects on the symptom severity of schizophrenia patients.. Corticosteroids are effective in various chronic inflammatory and auto-immune disorders. From the group of glucocorticosteroids, prednisolone has minor mineral-corticosteroid potencies, can adequately pass the blood-brain barrier (BBB) and its side-effects and safety profile are well known. Therefore, a study into treatment with prednisolone can provide as a proof of concept for immune modulation as a treatment for schizophrenia.
Method: In total 90 subjects, aged 18-70 years, diagnosed with schizophrenia, schizoaffective or schizophreniform disorder (Diagnostic and Statistical Manual of Mental Disorders-IV (DSM-IV) 295.*) or psychosis NOS (not otherwise specified) (298.9) will be included. The time interval between the onset of psychosis and study entry should not exceed seven years. Patients will be randomized 1:1 to either prednisolone or placebo daily for a period of 6 weeks. Study medication will be initiated at 40 mg for three days, after which it will be tapered down within 6 weeks after initiation, following current treatment guidelines. Primary outcome is change in symptom severity, expressed as change in total score on the Positive and Negative Symptom Scale (PANSS) from baseline to end of treatment. Cognitive functioning (measured through the Brief Assessment of Cognition in Schizophrenia; BACS) and change in Global Assessment Functioning (GAF) will be assessed, in addition to various immunological biomarkers. Secondary outcomes are a 4- and 6-month follow-up assessment of PANSS, BACS, GAF scores and immunological biomarkers. Additionally, a subgroup of patients can participate in the magnetic resonance imaging (MRI) part of the study where MR spectroscopy, structural, functional and diffusion MRI will be conducted.
Discussion: It is expected that prednisolone addition to current antipsychotic medication use will reduce symptom severity and will improve cognition when compared to placebo.
Trial registration: ClinicalTrails.gov NCT02949232 registered at 31 October 2016, retrospectively registered https://clinicaltrials.gov/ct2/show/NCT02949232?term=corticosteroid&cond=schizophrenia&rank=3 ; EudraCT-number 2014-000520-14 and 2017-000163-32.
Landfill Gas to Energy: A Demonstration Controlled Environment Agriculture System
Authors: Janes Harry , Cavazzoni James , Alagappan Guna , Specca David , Willis Joseph
Published: June 2019

A qualitative systems approach to controlled environment agriculture (CEA) is presented by means of several multi-institutional projects integrated into a demonstration greenhouse at the Burlington County Resource Recovery Complex (BCRRC), N.J. The greenhouse has about 0.4 ha of production space, and is located about 800 m from the about 40-ha BCRRC landfill site. A portion of the landfill gas produced from the BCRRC site is used for microturbine electricity generation and for heating the greenhouse. The waste heat from the turbines, which are roughly 15 m from the greenhouse, is used as the main heat source for the greenhouse in the winter months, and to desalinate water when heating is not required. Recovery of this waste heat increases the energy efficiency of the four 30-kW turbines from about 25% to 75%. Within the greenhouse, aquaculture and hydroponic crop production are coupled by recycling the aquaculture effluent as a nutrient source for the plants. Both the sludge resulting from the filtered effluent and the inedible biomass from harvested plants are vermicomposted (i.e., rather than being sent to the landfill), resulting in marketable products such as soil amendments and liquid plant fertilizer. If suitably cleaned of contaminants, the CO2 from the landfill gas may be used to enrich the plant growing area within the greenhouse to increase the yield of the edible products. Landfill gas from the BCRRC site has successfully been processed to recover liquid commercial grade CO2 and contaminant-free methane-CO2, with the potential for this gas mixture to be applied as a feedstock for fuel cells or for methanol production. Carbon dioxide from the turbine exhaust may also be recovered for greenhouse enrichment. Alternatively, algal culture may be used to assimilate CO2 from the turbine exhaust into biomass, which may then be used as a biofuel, or possibly as fish feed, thus making the system more self-contained. By recycling energy and materials, the system described would displace fossil fuel use, mitigating negative environmental impacts such as greenhouse gas emissions, and generate less waste in need of disposal. Successful implementation of the coupled landfill (gas-to-energy · aquaponic · desalination) system would particularly benefit developing regions, such as those of the Greater Caribbean Basin.
The Sino-American Botanical Expedition of 1980: A Retrospective Analysis of Success
Authors: Dosmann Michael S. , Del Tredici Peter
Published: June 2019

The 1980 Sino-American Botanical Expedition (SABE) to the Shennongjia Forest District, Hubei Province, China was the first botanical collecting trip by American scientists to that country since 1949. This collaborative venture with Chinese botanists yielded 2085 herbarium and 621 germplasm collections from the species-rich region. Our analysis tracked the fate of the SABE germplasm after its introduction to North America and represents one of the few case studies of its kind. Two hundred and fifty-eight of the original germplasm collections still survive and are in cultivation in at least one of 18 botanical institutions. Yet 115 of these (45%) are represented by a single accession growing in a single location, which suggests that the plant introduction process is more tenuous than is generally assumed. The scientific value of documented wild germplasm warrants that careful measures are in place to ensure that significant collections do not vanish. This case study outlines steps that can be taken throughout the introduction process (from propagation to distribution and follow-up) to prevent any such loss. In particular, the role of data sharing among institutions is highlighted as a means of identifying collection uniqueness, and assessing environmental adaptability and invasiveness.
Parent Identification of Eight Apple Cultivars by S-RNase Analysis and Simple Sequence Repeat Markers
Authors: Kitahara Kentaro , Matsumoto Shogo , Yamamoto Toshiya , Soejima Junichi , Kimura Tetsuya , Komatsu Hiromitsu , Abe Kazuyuki
Published: June 2019

As the parents of the some of the apple cultivars were unknown and others were uncertain, we investigated the parent-offspring relationships of eight apple cultivars by S-RNase analysis and SSR markers. The paternal parent of `Hida' was identified as `Golden Delicious', not the previously mentioned `Orin'. It was indicated that `Ryoka No Kisetsu' and `Korin' showing identical SSR genotype are likely sports of `Fuji'. `Fuji', rather than `Toko', seemed to be a maternal parent of `Kotoku', but was not a paternal parent of `Orei', `Starking Delicious', `Nero 26', `Empire', or `Aori 3'. Previously mentioned `Mutsu', `Indo', and `Shin Indo' were excluded as paternal parents of `Hokuto'. `Tsugaru' and `Jonathan' and were identified as the respective paternal parents of three cultivars described as having unknown paternal parents, i.e., `Aika No Kaori', `Yoko', and `Tsugaru'.
Screening Malus Seedlings for Cold Hardiness
Authors: Mathers H.M. , Stushnoff C.
Published: June 2019

Twelve-week-old Malus seedlings were induced to cold harden by exposure to low temperature and freezing environments. The effectiveness of induced acclimation by exposure to stimuli such as low temperature (3 to 5 °C), frequency of exposure to freezing temperatures (-3 °C), storage time before and after induction and the effects of different screening temperatures (-20, -30, and -40 °C) were investigated with seedlings grown in a greenhouse from open-pollinated `Golden Delicious' apple (Malus pumila (Mill.), `Antonovka' apple (M. baccata (L.) Borkh. × (M. pumila) and `Rescue' apple (M. baccata) × (M. pumila). Differentiation of the seedling populations with respect to cold hardiness was not achieved until after acclimation at cool temperatures (3 to 5 °C) for 6 weeks. Further population differentiation was achieved by exposure to one or more frosts (-3 °C). Once the acclimation response had been initiated the seedlings could be held for up to 11 days, under the same conditions, with no significant decrease in hardiness. Hardiness levels of acclimated and nonacclimated open pollinated seedlings coincided with known inherent hardiness responses for all three maternal cultivars evaluated. A binomial form of regrowth data collection, percent seedling survival, was determined to be the most efficient and most precise measure of evaluation. Induction of cold hardiness in very young seedlings and the use of a controlled freeze testing protocol should facilitate rapid screening of large progenies and improve the rate of progress in breeding for cold hardiness.
Sequences of Probes Revealing Mapped Restriction Fragment-length Polymorphisms in Cucumber
Authors: Havey Michael J.
Published: June 2019

PstI-genomic and cDNA clones revealing mapped restriction fragment-length polymorphisms (RFLP) in cucumber (Cucumis sativus L.) were sequenced in order to ensure that these clones remain available and to determine if any clones showing genetic linkage in cucumber are physically linked in Arabidopsis thaliana. Sequence comparisons using translated searches revealed that 80% of the cucumber cDNA clones showed significant (≤e-20) similarities to Arabidopsis expressed sequence tags (ESTs) or genomic sequences, as opposed to relatively few (32%) of the cucumber genomic clones. Two clones revealing RFLPs linked at 2 cM in cucumber showed significant (≤e-20) similarities to sequences separated by 347,616 basepairs on chromosome 4 of Arabidopsis.
Genotyping Fruiting Mei (Prunus mume Sieb. et Zucc.) Cultivars Using Amplified Fragment-length Polymorphism Markers
Authors: Fang J. , Qiao Y. , Zhang Z. , Chao C.T.
Published: June 2019

We used amplified fragment length polymorphism (AFLP) markers to analyze 14 fruiting mei cultivars from China and Japan. The levels of polymorphism and genetic relationship among cultivars were studied using two types of AFLP primer combinations [EcoR I + Mse I (E+M) and EcoR I + Taq I (E+T)] and the combined data from both types of primer combinations (E+M+T). The polymorphism among the cultivars was 57.92% based on E+M primers and 63.04% based on E+T primers. All three dendrograms generated by the three sets of data showed similar relationships among the fruiting mei cultivars. The corresponding main clusters contained the same cultivars and the subgroups correlated closely with the known geographic origins of the cultivars.
Pollination Biology of Hydrangea macrophylla
Authors: Reed Sandra M.
Published: June 2019

Little information is available on the reproductive behavior of Hydrangea macrophylla (Thunb. Ex J.A. Murr.) Ser. The objectives of this study were to investigate time of stigma receptivity, viability of pollen from sterile flowers, and self-incompatibility in this popular ornamental shrub. Pollen germination and pollen tube growth in styles were examined using fluorescence microscopy. Stigma receptivity was examined in cross-pollinations made from 1 day before anthesis to 8 days after anthesis. Maximum stigma receptivity for the two cultivars examined occurred from anthesis to 4 days after anthesis. Viability of pollen from sterile flowers was evaluated through pollen staining and observations of pollen tube growth. No significant difference in percent stainable pollen between fertile and sterile flowers was observed in any of the six taxa examined. Pollen germination and pollen tube growth were studied in cross-pollinations made using pollen from fertile and sterile flowers of two cultivars. For both cultivars, pollen tubes from fertile and sterile flowers grew to the same length and had entered ovules by 72 hours after pollination. Self-incompatibility was evaluated by comparing pollen germination and pollen tube growth in cross- and self-pollinations. In the five taxa examined, self pollen tubes were significantly shorter than cross pollen tubes in flowers that were examined 72 hours after pollination. This finding indicates the presence of a gametophytic self-incompatibility system in H. macrophylla.
Removal of the Most Developed Flowers Influences Fruit Set, Quality, and Yield of Apple Clusters
Authors: Miranda Carlos , Santesteban Luis G. , Royo José B.
Published: June 2019

The apical or king (K) flower in the apple (Malus ×domestica L. Borkh.) cluster usually develops and blooms first and also has a greater sink potential. For this reason, resources are primarily used by the K fruit, and this is also one of the reasons why most thinning practices tend to favor K fruit set. However, it is not always possible to retain the K flower and remove the lateral ones. This study was undertaken to determine if the removal of the most developed flowers in the cluster influences yield or quality compared to that obtained in a whole cluster. The treatments were made in `Golden Delicious' and `Royal Gala' apple cultivars, within a wide range of flower densities for each cultivar. The factor tested was the intensity of flower removal (FRI); the treatments consisted in removing one, two, or three flowers in each cluster. Flower density was used as a covariate in an analysis of covariance to account for differences in flower densities in response to FRI treatments. In all experiments the covariate was not significant; therefore FRI effect was not affected by flower density. `Golden Delicious' and `Royal Gala' had similar responses to flower removal, so that when at least three flowers in a cluster remained, fruit set and cluster yield were similar to whole clusters. Only when two or fewer poorly developed flowers remained after FRI treatments, yield was reduced by as much as 25%. Fruit from FRI clusters were even heavier than those from whole clusters, due to reduced competition among the fruit, so that the growth potential of fruit from the first and second lateral flowers was similar to clusters with K fruit, in clusters where the K flower had been removed.
Growth and Yield of Watermelon on Polyethylene Mulch with Different Spacings and Nitrogen Rates
Authors: Goreta Smiljana , Perica Slavko , Dumicic Gvozden , Bucan Lovre , Zanic Katja
Published: June 2019

Suggested watermelon planting densities and N rates vary on a large scale, indicating that there is insufficient knowledge about their effects. Therefore, the objective of this study was to evaluate the effects of N rate and planting density on growth, yield and quality of watermelon [Citrullus lanatus (Thunb.) Matsum & Nakai] grown on black polyethylene mulch. The field experiments with `Crimson Sweet' watermelon were conducted in two climatologically different growing regions. The treatments were factorial combinations of three in-row plant spacings (0.5, 1.0, and 1.5 m) and three N rates (115, 195, and 275 kg·ha-1). Part of the N (35 kg·ha-1) was applied preplant and the remainder was fertigated. Vine length increased linearly up to 7 weeks after planting (WAP) as N rate increased from 115 to 275 kg·ha-1, and up to 9 WAP as plant spacing increased from 0.5 to 1.5 m. Total and marketable yields per ha or per plant did not increase with N rates above 115 kg·ha-1. Average fruit weight and fruit size distribution were generally unaffected by N rate. Leaf N concentration increased as N rate increased, although leaf N concentrations at the lowest N rate (115 kg·ha-1) even at 9 WAP were relatively high (43.3 to 47.3 g·kg-1). Total and marketable yields per ha were linearly decreased with an increase in plant spacing from 0.5 to 1.5 m, and the same was noticed with the total and marketable number of fruit per ha. With increased plant spacing average fruit weight increased and fruit size distribution shifted to larger categories.
Potential Use of a 24-Hour Photoperiod (Continuous Light) with Alternating Air Temperature for Production of Tomato Plug Transplants in a Closed System
Authors: Ohyama Katsumi , Manabe Koji , Omura Yoshitaka , Kozai Toyoki , Kubota Chieri
Published: June 2019

To evaluate the potential use of a 24-hour photoperiod for transplant production in a closed system, tomato (Lycopersicon esculentum Mill.) plug transplants were grown for 17 days either under a 24-hour photoperiod with a photosynthetic photon flux (PPF) of 200 μmol·m-2·s-1 or under a 16-hour photoperiod with a PPF of 300 μmol·m-2·s-1, resulting in the same daily integrated PPF (17.3 mol·m-2). Air temperatures were alternated between 28 °C during the first 16 hours and 16 °C for the subsequent 8 hours of each day. Fresh weight, dry weight and leaf area were 41%, 25%, and 64% greater, respectively, under the 24-hour photoperiod than under the 16-hour photoperiod. Physiological disorders (e.g., chlorosis and/or necrosis) were not observed under the 24-hour photoperiod, probably due to the alternating air temperature. Floral development of plants originating from both treatments did not differ significantly. Electric energy use efficiency of the closed system was 9% greater under the 24-hour photoperiod than under the 16-hour photoperiod. These results suggest that using a 24-hour photoperiod with relatively low PPF can reduce both initial and operational costs for transplant production in a closed system due to the reduction in the number of lamps.
Effects of Repeated Yearly Application of Chemical Thinners on `McIntosh' Apples
Authors: Greene Duane W.
Published: June 2019

An experiment was initiated on mature `Morespur McIntosh'on M.7 rootstock to document the effects of repeated yearly applications of benzyladenine (BA) and naphthaleneacetic acid (NAA) on fruit quality at harvest, the development of storage disorders following regular air storage, and on return bloom. When analyzed over the 4-year period, thinning did not significantly reduce crop load. This result was due in large part to no thinning response one year and very poor set on all trees in another year. Thinners were effective at increasing return bloom over the course of the experiment. BA increased fruit weight but reduced red color compared with NAA treated and control trees. Fruit quality differences at harvests were attributed primarily to crop load effects. There were no fruit quality, return bloom, or storage disorders that could not be explained by treatment effects on crop load or due to previously known effects of individual thinners. The results of this experiment clearly suggest that there are no direct adverse effects following repeated use of either NAA or BA.
Multivariate Repeated Measures Analysis of Plant Growth Regulators on Tradescantia virginiana
Authors: White Sarah A. , Scoggins Holly L. , Marini Richard P. , Latimer Joyce G.
Published: June 2019

Little information is available on cultural requirements for greenhouse production of Tradescantia virginiana L. We tested three plant growth regulators (PGRs) at ascending rates on T. virginiana `Angel Eyes,' `Blue Stone,' and `Red Cloud' in an effort to find appropriate application levels for height suppression. Treatments applied two weeks after transplant. Each PGR was applied once at the following rates: paclobutrazol at 0, 40, 80, 120, or 160 mg·L-1, uniconazole at 0, 15, 30, 45, or 60 mg·L-1, or flurprimidol at 0, 15, 30, 45, 60, or 75 mg·L-1. Repeated measures experimental design and multivariate analysis was used to examine plant responses to PGRs over time. The most effective paclobutrazol rate for adequate height suppression was 120 mg·L-1. Uniconazole at 30 to 45 mg·L-1 and flurprimidol at 45 to 60 mg·L-1 resulted in adequate height control. `Blue Stone' and `Red Cloud' appeared more responsive (greater suppression of height at rates applied) to both uniconazole and flurprimidol than `Angel Eyes.' These results suggest that cultivars respond in a different manner to PGRs applied to them; more compact growth can be obtained for cultivars tested using these suggested rates. Chemical names used: trifuloromethoxy phenyl-5-pyrimidinemethanol (flurprimidol); [(±)-(R*,R*)-ß-((4-chlorophenyl) methyl)-?-(1,1,-dimethylethyl)-1H-1,2,4,-triazole-1-ethanol)] (paclobutrazol); uniconazole.
Powdery Mildew Resistance in the U.S. National Plant Germplasm System Cucumber Collection
Authors: Block Charles C. , Reitsma Kathleen R.
Published: June 2019

Nine hundred and seventy-seven (977) cucumber (Cucumis sativus L.) accessions from the U.S. National Plant Germplasm System (NPGS) collection were tested for resistance to powdery mildew, caused by the fungus Podosphaera xanthii (Castagne) Braun and Shishkoff, formerly known as Sphaerotheca fuliginea (Schlecht.) Poll. Plants from each accession were evaluated in the greenhouse following inoculation with field isolates of P. xanthii. Each plant was placed into one of three susceptibility classes based on the amount of fungal growth and sporulation on the hypocotyl, stem, petioles and leaves - susceptible (S), intermediate (I) or resistant (R). Of the 977 accessions (9.6%), 94 contained at least one I or R-type plant. Seventeen of the 20 most-resistant accessions came from Asian sources, including China (PIs 418962, 418964, 432860, and 432870), India (PIs 197085, 197088, and 605930), Japan (PIs 279465, 288238, 390258, and 390266), Pakistan (PI 330628), the Philippines (PIs 426169 and 426170), and Taiwan (PIs 321006, 321009, and 321011). A quantitative study was conducted to compare mildew reproduction on S, I, and R-type cucumbers in the greenhouse and under field conditions in Ames, Iowa. Leaf disks were removed weekly and microscopic counts made of spore populations. The leaf disk method was superior to visual rating for ranking and differentiating intermediate from resistant accessions. Both the intermediate (moderately resistant) and highly resistant accessions provided excellent protection against powdery mildew in the field.
Effect of Cold Acclimation and Freezing on Spring Dead Spot Severity in Bermudagrass
Authors: Iriarte F.B. , Fry J.D. , Martin D.L , Todd T.C. , Tisserat N.A.
Published: June 2019

Spring dead spot (SDS), caused by three root-infecting species of Ophiosphaerella, is a destructive disease of bermudagrass (Cynodon spp.L.C. Rich). We tested the effects of incubation temperature and duration, and exposure to decreasing freezing temperatures on bermudagrass shoot survival following inoculation with SDS pathogens. Inoculated plants exposed to freezing temperatures as high as -2 °C following a two month incubation exhibited extensive shoot mortality and had SDS symptoms consistent with those observed in the field. Lowering the freezing temperature from -2 to -8 °C increased disease severity and shoot mortality on noninoculated bermudagrass. Inoculated bermudagrass incubated for 1 month in the greenhouse, then for an additional month at 4 °C had greater shoot mortality following freezing than plants incubated at 25 °C. Although cold acclimation and freezing intensified SDS symptoms, the technique did not reliably distinguish between resistant and susceptible cultivars.
Basal Medium with Modified Nitrogen Source and other Factors Influence the Rooting of Banana
Authors: Wu Yuanli , Yi Ganjun , Yang Hu , Zhou Birong , Zeng Jiwu
Published: June 2019

MS is the most commonly used basal medium for the micropropagation of banana (Musa spp.), in which inorganic N source consists of NH4+-N and NO3--N, and NH4+:NO3- = 1:2. In the present study, basal medium for rooting culture was modified by supplying NO3--N as the sole N source at the concentration of 17.80 to 19.78 mmol·L-1. Not only was the percentage of qualified plantlets higher than that of MS or ½ MS, but the cost for medium preparation (per liter) was about $0.6 lower than that of MS based on local retail price, for the concentration of N decreased from about 60 mmol·L-1 to nearly 20 mmol·L-1. The effects of four factors: sucrose (25 to 35 g·L-1), NAA (0.2 to 1.0 mg·L-1), IBA (0.2 to 1.0 mg·L-1), and basal medium with modified N source on the percentage of qualified plantlets were studied by using orthogonal design. The variance analysis of data showed that all the four factors significantly affected the process of rooting culture. Among them, sucrose was the most important factor, followed by revised basal medium, IBA, and NAA. The optimal medium for rooting culture was BM II supplemented with 30 g·L-1 sucrose, 0.5 mg·L-1 NAA, and 0.5 mg·L-1 IBA. During the following acclimation phase, >90% of plantlets survived. Chemical name used: 6-benzylaminopurine (BA); indole-3-butyric acid (IBA); α-naphthaleneacetic acid (NAA).
Fertilization Program and Resin Foam Soil Amendment Effects on Sod Establishment
Authors: Nektarios Panayiotis A. , Tsoggarakis Georgios , Nikolopoulou Aimilia-Eleni , Gourlias Dimitrios
Published: June 2019

Two field studies (winter and summer) were performed to evaluate the effect of three different fertilizer programs and a urea formaldehyde resin foam (UFRF) soil amendment on sod establishment and anchorage. Fertilizer treatments involved were 1) a quick release (QR) granular fertilizer (12-12-17); 2) a slow release (SR) fertilizer (27-5-7); and 3) a foliar (FL) fertilizer (20-20-20). The application rate was 50, 30, 0.35 g·m-2 for QR, SR, and FL, respectively. The substrate consisted of sandy loam soil, and in half of the plots UFRF flakes were incorporated in the upper 100 mm at a rate of 20% v/v. The effects of the fertilizer and soil amendment on sod establishment were evaluated through measurements of the dry weight of clippings and roots and the visual quality of the turf. Sod anchorage was measured by determination of the vertical force required to detach a piece of sod. For each treatment the initial and final pH, EC, available P, exchangeable K, Ca, Mg, and Fe were also determined. It was found that FL reduced clipping yield but retained turf visual quality similar to the other fertilizer treatments except in winter, when it resulted in the worst quality ratings. However, FL fertilizer promoted root growth and provided high vertical detachment force values and therefore enhanced sod establishment. Slow release fertilizer resulted in moderate top growth and visual quality of the turf during winter, but delayed sod establishment. Quick release fertilizer increased top growth and improved turfgrass visual quality during the winter, but root growth and vertical detachment force were reduced, indicating poorer sod establishment. UFRF did not enhance sod establishment since there was a negative effect on root growth when temperatures were below 10 °C, without however affecting vertical detachment force. Differences in soil P, K, Ca, Mg and Fe between treatments were inconsistent between the two studies, except for final K concentration, which was higher for QR fertilization than SR and FL. Foliar fertilization can enhance sod establishment compared to QR and SR, by accelerating sod anchorage and root growth. QR can be used in late autumn to improve winter green up of the sod. UFRF does not improve or accelerate sod establishment and possesses a minimal capacity to improve soil properties of sandy loam soils.
Comparison of `Marion' to Thornless Blackberry Genotypes as Individually Quick-frozen and Puree Products
Authors: Yorgey B.M. , Finn C.E.
Published: June 2019

The trailing blackberries (Rubus sp. L.), particularly `Marion', are the primary blackberries grown for the processing market and they are largely machine harvested. While `Marion' is well known for its processed fruit quality, particularly flavor, aroma, and perception of low seediness, it has spines (thorns) that can be dislodged when machine harvested and end up in the product. A primary goal of the USDA–ARS blackberry breeding program in Corvallis is the development of cultivars that are comparable to `Marion' in fruit quality but are spineless (thornless). Nine thornless selections were compared with four standard cultivars as individually quick-frozen (IQF) and puree products in a blind evaluation. Each sample was scored panelists from the blackberry industry and research program. IQF samples were scored for appearance, color, seediness, flavor, and overall quality by 21 panelists and purees were scored for color, flavor, aroma, and overall quality by 25 panelists. Both panels used a 9 point hedonic scale (1 = dislike extremely, 5 = neither like nor dislike, 9 = like extremely). With the exception of color, there were significant differences among all genotypes for all traits evaluated in the IQF and pureed products. ORUS 1380-1 was ranked similar to `Marion' and significantly better than `Waldo', in overall quality of the IQF product. In puree form, ORUS 1843-1 and ORUS 1843-3 had the highest ranking in overall quality, but were only both statistically different from ORUS 1489-2. For pureed product flavor, ORUS 1843-1 was the highest rated selection but was not statistically different from `Marion'. While ORUS 1843-1 and ORUS 1843-3 hold great promise, they are from a cross between wild collected Rubus ursinus Cham. & Schlt. and `Waldo' and as a result have some negative characteristics of the native species, particularly small fruit size. The puree quality of NZ 9128R-1, NZ 9351-4 and ORUS 1380-1 was similar to `Marion' and these genotypes offer promise as thornless replacements for `Marion'.
Fine-tuned Head Weight Estimation in Globe Artichoke (Cynara scolymus L.)
Authors: Düzyaman Eftal , Düzyaman Basak Ünver
Published: June 2019

A novel and nondestructive method for head weight estimation in globe artichoke was described. Linear measurements on head height (h) and head diameter (2r) were performed on head samples of five cultivars and one developed clone having cylindrical, conical or spherical head forms. The measurements on 2r were performed at the base in conical- and cylindrical-headed cultivars, while they were taken equatorially in spherically headed cultivars. Correlation and regression analyses were performed between single true head weights and eight different models [h, r, 2r, r3, r2h, πr2h (cylinder volume), ⅓πr2h (cone volume) and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\frac{4}{3}{\pi}r^{3}\) \end{document} (sphere volume)]. Since πr2h and ⅓πr2h are folds of r2h, and \batchmode \documentclass[fleqn,10pt,legalpaper]{article} \usepackage{amssymb} \usepackage{amsfonts} \usepackage{amsmath} \pagestyle{empty} \begin{document} \(\frac{4}{3}{\pi}r^{3}\) \end{document} of r3; r2h or r3 had completely the same correlation coefficients as their folds, and hence were equally effective in the statistical analyses. Head weights were more precisely estimated when the r2h model (or their folds) was used for cylindrical and conical heads and the r3 model (or their folds) for spherical heads then any other model. Coefficients of determination (R2) explained the highest variability observed for true head weights when the r2h model was used as the independent variable in the regression analysis for cylindrical and conical cultivars (96.6% to 97.5%) and the r3 model for the spherical cultivars (96.6% to 98.4%). Even though all correlation coefficients and regression F values were very highly significant (p < 0.001), 81% of estimated cases had <10% deviations when one of the appropriate models were used in comparison to 66% of the estimated cases having <10% deviations when, for example, the 2r model was used, the second most effective model for all types of heads. The agreement between true and estimated head weights was also tested, where the bias was lower for a cultivar-specific model vs. the 2r model. Discussions on applying the results to the selection procedures were made.
Nuclear Genome Diversity and Relationships among Naturally Occurring Buffalograss Genotypes Determined by Sequence-related Amplified Polymorphism Markers
Authors: Gulsen O. , Shearman R.C. , Vogel K.P. , Lee D.J. , Baenziger P.S. , Heng-Moss T.M. , Budak H.
Published: June 2019

Buffalograss [Buchloe dactyloides (Nutt.) Engelm.] has the potential for increased use as a turfgrass species due to its low maintenance and water conservation characteristics. This study was conducted to estimate diversity and relationships among naturally occurring buffalograss genotypes based on the nuclear genome, using sequence-related amplified polymorphism (SRAP) markers. The 56 genotypes studied represented five ploidy levels collected from diverse geographic locations in the North American Great Plains. In addition, blue grama [Bouteloua gracilis (H.B.K.) Lag. Ex Steud.] and perennial ryegrass (Lolium perenne L.) were included as outgroups. Twenty-five combinations of forward and reverse primers were used. Ninety-five intensively amplified markers were scored and used to infer diversity and relationships among the genotypes. All buffalograss genotypes were discriminated from each other with similarity values ranging from 0.70 to 0.95. Principal component analysis (PCA) suggested that the 56 genotypes could be reduced to 50 due to high similarity levels among some of the genotypes. The distance between buffalograsses, blue grama, and perennial ryegrass were consistent with current taxonomical distances. This research indicates that SRAP markers can be used to estimate genetic diversity and relationships among naturally occurring buffalograss genotypes.